MULTIPLE MYELOMA

A SUMMARY OF SOME KEY INFORMATION AND ISSUES

Ronald E. Merrill

Draft 6.4, June 1997

CHARACTERISTICS OF MULTIPLE MYELOMA

Multiple myeloma, sometimes called myelomatosis, is a relatively uncommon cancer of plasma cells. (This disease should not be confused with myelodysplastic syndrome or myelo- proliferative disorders, which are different.) It is called "multiple" because the malignancy spreads throughout the bone marrow into all the major bones; when confined to a single site, the disease is known as "solitary plasmacytoma," which has a much better prognosis. (However, a recent study found that, by MRI, about 50% of solitary plasmactyoma cases are actually MM.) The disease seems to develop very slowly, and in the early stages may be characterized as MGUS ("monoclonal gammopathy of unknown significance") or "indolent" or "smoldering" myeloma. MGUS is actually rather common in older people: 1% (> age 65), 3% (> age 70), 10% (> age 80) [Back 1997; Rettig 1997]. Related to multiple myeloma are other "plasma cell dyscrasias," such as Waldenstrom's macroglobulinemia. The disease is the subject of numerous review articles. [Varterasian 1995; Alexanian 1994; Oken 1994; Mandelli 1992] A recent book has appeared. [Malpas 1995]

Multiple myeloma is estimated to strike about 2-3 out of every 100,000 persons, and about 10,000 Americans die of it each year. Men get the disease somewhat more often than women. Blacks are more likely to get the disease than whites, who in turn are more susceptible than orientals. Typically it has been a disease of the elderly; anecdotal evidence suggests that it is now striking people in middle age more frequently. However, this impression may be due simply to more effective diagnosis. The causes of the disease are not well understood. It is known from studies of the Hiroshima survivors that exposure to radiation can cause multiple myeloma. There is speculation that chemical exposure may be implicated, but no firm evidence; specifically, farmers, who are exposed to pesticides, are more likely to get the disease. Exposure to benzene has also been suggested as a causative factor. Orientals who live in the US have a higher rate than those in their native countries, which suggests a possible dietary component to causation. Recently it has been found [Rettig 1997] that a herpes virus is associated with the disease. It is also proposed [B. Durie, private communication] that a retrovirus infection may be a source of the disease.

Multiple myeloma causes anemia, as the normal blood-producing functions of the bone marrow are "crowded out" by the abnormal plasma cells. Commonly there is damage to the bone, which begins to dissolve. This can be extremely painful, and broken bones and spinal damage can immobilize the patient. The abnormal plasma cells produce huge amounts of unnecessary immunoglobulin (known as "paraprotein" or "M-protein"); this can poison or clog up the kidneys, causing kidney failure [Alexanian 1990; Winearls 1995]. Finally, the immune system fails to function properly in multiple myeloma patients; as a result infection, especially pneumonia, is the most common cause of death in this disease. About 40-67% of myeloma patients die of infection. Eventually the disease tends to progress to plasma cell leukemia, with at that stage a very short prognosis.

Background: Some General Characteristics of Tumor Cells

A tumor becomes detectable (at least by classical methods) when it contains around 10**9 cells, and lethal at around 10**12 cells.

Contrary to common belief, tumor cells in general do not divide more rapidly than normal cells. (Note that this more or less explodes the original theoretical justification, still widely cited, for cytotoxic chemotherapy!) There is wide variation in doubling times in both classes of human cell:

Tumor Examples: Normal Cell Examples:

Burkitt's lymphoma 24 hrs WBC precursors 12 hrs

acute leukemia 2 wks rectal mucosal 24 hrs

breast cancer 3 mos

multiple myeloma 6-12 mos

The "growth fraction" (cells dividing or committed to division, divided by total cells) ranges from 0.2 to 0.7 for typical tumors. However, growth of the tumor must not be confused with the proliferation of the cancer cells.

Tumor growth is approximately exponential over short time periods, and follows usually a Gompertz function (exponential with exponentially increasing doubling time) in the long run. Presumably tumor growth slows down as cube-square effects become significant, and the interior of the tumor suffers a shortage of blood flow and oxygen. The doubling times for tumor volume typically are surprisingly long, much longer than would be predicted from the growth fraction of the cells.

Cancer cells in vitro generally proliferate much faster. There are several factors which could be involved:

1. Tumors can be heterogeneous, with most of the cancer cells having reverted to a resting state. When cells are grown in vitro, sample bias occurs; typically only a tiny fraction of cells spotted on the plate will grow, and one would expect these to be the cancerous "stem" cells that are dividing rapidly.

2. Sample bias might affect results even if all the cells in the tumor are dividing; those that divide the fastest might be most likely to "take" on the plate.

3. The cell culture environment is different from the in vivo environment, and may be more favorable to cancer cell growth.

One viewpoint says that cancer cells evolve. Free from the normal homeostatic constraints, malignant cells become a Darwinian population and compete with one another. Those that drop normal cell activities and devote the resources thus freed to growth and proliferation tend to win the competition. The original functions of the cell line are gradually discarded except to the extent that they are necessary for metabolism or for protection from the immune system or therapy. Ontogeny, or rather oncogeny, recapitulates phylogeny--backwards. The cancer speciates, so to speak, into an increasingly heterogeneous population of more primitive unicellular organisms. A process of evolution drives the development of the most rapidly reproducing and metastasizing variants. On this hypothesis one would predict that cells in a particular tumor would become less differentiated and faster-growing as time passes; and this does seem to be the case.

The evolutionary paradigm suggests the difficulty of treating cancer, and offers theoretical justification for the empirically derived ruthlessness so characteristic of oncologists. There is, in this perspective, little prospect of a "magic bullet" that will kill cancer cells and not normal body cells. Once the disease has progressed beyond a certain point, "kill 'em all--let God sort 'em out" may be the only effective policy.

There are a number of metabolic differences between cancer cells (more or less in general) and normal cells. For instance, many cancer cells are unable to synthesize L-asparagine; this at one time led to excitement over the potential of L-asparaginase as a treatment. As another example, lipid mobilization in tumors is directed toward membrane synthesis and not energy production. Cancer cells also run glycolysis faster than the citric acid cycle can keep up, so that lactate builds up, perhaps lowering pH in the cell. This also affects the redox potential of cancer cells, which is suggestive in view of the anti-cancer effects of anti-oxidant nutrients.

More recently, it has been discovered that cancer cells express an enzyme called "telomerase." This rebuilds the telomeres which protect the ends of the chromosomes; normally they are shortened with every cell division, resulting in cell death when they run out. This explains why cancer cells (and certain specialized cells, such as male germ cells) are immortal.

Characteristics of Multiple Myeloma: An Unusual Cancer

Multiple myeloma appears to be a very unusual cancer in many ways:

* Unlike most cancers, myeloma is not routinely immortal in vitro; indeed, it is exceptionally hard to culture at all.

* Multiple myeloma rarely shows metastasis into other organs, even those where normal plasma cells reside; it grows almost exclusively in the bone marrow.

* The tumor grows slowly, though normal plasmacytes divide rapidly. (However, when myeloma cells are successfully cultured, they do seem to proliferate with a doubling time of days. It should be noted, though, that whether the cell lines commonly used really represent true myeloma lines is often questionable [Pellat-Deceunynk 1995].)

* Early treatment of multiple myeloma does not prolong survival. This is in strong contrast to most cancers, where early treatment of the disease strongly improves prognosis.

* Unlike most slow-growing tumors, multiple myeloma is usually quite responsive to chemotherapy or radiation. Interestingly, when a myeloma bone lesion is eliminated by radiation, the myeloma typically does not recur in that location during the life of the patient.

* Chemotherapy generally cannot eliminate myeloma; tumor burden is reduced to a certain point ("plateau") and then further therapy is ineffectual.

* And, unlike most cancers responsive to therapy, multiple myeloma is incurable.

* In humans at least (mice are different), myeloma cells continue to express paraprotein, in spite of the metabolic load this places on the malignant cell. However, the production is much lower on a per-cell basis than that of normal plasma cells [Klein 1995 and cited refs].

In the last few years, it has become clear that regarding multiple myeloma as a cancer of plasma cells is inadequate. Currently a new paradigm is taking shape, in which the true malignancy is seen as residing in a small population of abnormal B-cells in the circulating blood. The tumor mass of plasmacytes is merely a by-product. However, this hypothesis of a "malignant compartment" remains very controversial.

Linda Pilarski [personal communication, 1995] suggests that MGUS is a more or less normal immune response to a chronic antigen stimulation. Multiple myeloma represents a malignant branch from this clone. However, the original MGUS does not go away. This is why complete remission is rare (except after BMT, when the entire immune system is burned out); there is always paraprotein due to the MGUS. In plateau phase, the patient essentially has returned to MGUS, though a few malignant cells remain. Pilarski freely admits that this is speculative.

Multiple Myeloma: The Modern Synthesis

The normal course of response by B-cells to an infection is as follows: (1) A memory B-cell finds its antigen is present. (2) It starts proliferating, producing a few more memory B-cells and many plasma cells, which migrate to the bone marrow. (3) The plasma cells proliferate strongly and pump out antibodies to the specific antigen that stimulated the response. (4) The B-cells get a message that the job is being done (probably a cytokine messenger) and go back to sleep. (5) The plasma cells complete their programmed proliferation, produce the needed antibodies, and die. The whole process is quite rapid; most normal plasmacytes live from a few days to a month.

Multiple myeloma results from a disorder in this process. A reasonable hypothesis as to what happens might be: (1) A defective memory B-cell turns on, possibly in response to an infection. (2) However, the cell differentiation process goes haywire; the plasma cells express antibody, but do not proliferate with their normal rapidity and instead retain the long lifespan of the memory B-cell.

This conjecture has the potential to explain most of the strange characteristics of multiple myeloma. The actual cancer, in this view, lies in the small population of circulating B-cells; the plasma cell tumor is a by-product. This explains the slow growth of the disease. [Drewinko 1981] The dividing B-cells are responsive to chemotherapy, but the disease always comes back because the slow-growing plasma cells are not hit so hard by the chemo, and they provide a reservoir from which new malignant B-cells can be recruited. Note that the plasma cells, not being cancerous, have no reason to drop their antibody production.

There are conflicting views as to the quality of the antibodies produced by myeloma cells. A 1985 book says that the paraprotein is abnormal and may be an antibody to something normally present in the body. (This, if true, would provide a temptingly elegant theory as to the genesis of the disease.) However, Kuby's text on immunology (1992) is quite explicit that multiple myeloma cells express normal immunoglobulin, and states that in some patients the paraprotein has been characterized as antibody to known pathogens. On the third hand, Dr. James Berenson (UCLA) told me that myeloma paraprotein is abnormal.

Several groups have proposed--though this remains controversial--that the proliferative population of cells in myeloma consists of some form of B-cell in the peripheral circulation. [Pilarski 1992; Klein 1992; Epstein 1992] The clonal plasma cells themselves are viewed as playing a more or less passive role, though it is suggested that they may under certain circumstances spread the disease to other bone marrow locations. [Potter 1992] Possibly relevant here is the observation that progressive myeloma may become non-secretory. [Hicks 1989; Dimopoulos 1992]

Linda Pilarski believes that the malignant compartment consists of CD19+ B-cells in the peripheral blood. In fact, she suggests that essentially all of the CD19+ cells in the blood are malignant, a radical notion that is accepted by few other researchers. [Pilarski 1995; Pilarski 1997] Epstein, for instance, asserts that less than 1% of CD19+ cells in the blood are clonotypic. [Epstein 1995] (See also an exchange of notes [Kay/Pilarski 1995].) Epstein points out these CD19+ cells do not increase with disease progression, and in fact there is no evidence that they are "malignant" in any ordinary sense. Epstein tried using anti-CD19+ antibodies conjugated to ricin, and found that the CD19+ cells came back [Epstein 1997].

Along these lines, it is interesting to note that Kawano finds that myeloma plasmacytes are CD19-; normal plasmacytes, like their B-cell precursors, are CD19+. [Kawano 1995] This suggests that loss of CD19 expression plays an important role in development of myeloma, but does not actually contradict Pilarski's hypothesis. Interestingly, about 30% of myeloma patients have low CD19+ counts, and this is a risk factor for infection, which reduces survival.

The clonogenic CD19+ cells cannot be made to produce a continuous cell culture [Van Camp 1997]. This suggests that they are not really cancerous in the normal sense. A comparative study of peripheral blood (PB) and bone marrow (BM) clonal MM cells in six patients presents very interesting results [Van Ness 1997]. In none of the six patients did transplant reduce the PB MM cells. (And there is evidence that these cells are resistant at least via the MDR PGP route.) And, though the sample size is very small, it is notable that in the two cases where PB MM cell count was high, the patient quickly relapsed after transplant. But PB MM cell counts did not increase during relapse; they stayed roughly constant. Recent evidence indicates that peripheral blood cells with clonal myeloma characteristics are very stable and are essentially untouched by chemotherapy, even at BMT levels [Billadeau 1997].

Perhaps the CD19+ compartment is really memory-cell like and has a low proliferative capacity. It is the source of the malignancy, acts as a reservoir, but the actual growth occurs at the plasmablastic stage.

It has been suggested [Maitland 1990] that multiple myeloma exhibits a "homeostatic" behavior. These authors found evidence that the disease actually becomes more aggressive after chemotherapy with cyclophosphamide. Their interpretation was that reduction in tumor mass stimulates the remaining myeloma cells to proliferate. (This might be congruent with the above theory, if we accept the idea that the B-cells proliferate because of failure to get a feed-back signal that plasma cell formation is complete.) They cite evidence that myeloma cells have more primitive morphology in patients who become refractory to treatment and that more primitive cells may thus be more drug resistant. Maitland's own work indicates that MM cells may be either large/plasmacytoid or small/lymphoplasmacytoid, and that the latter are more drug resistant. As the disease progresses, the cells tend to shift to the small type.

*---> The pathologist's report on my bone marrow asserted that the plasmacytes are unusual and look more like Waldenstrom's macroglobulinemia--which are bigger than MM cells. It has been found (Greipp, ASCO meeting report) that patients with over 2% of plasmablasts (very immature plasma cells) in the bone marrow have poor prognosis.

The therapeutic implications of the emerging model of myeloma might be profound. First, if the true malignancy is in a peripheral B-cell population, chemotherapy and other treatments ought to be aimed primarily at this rather than at the plasma cells. [Pilarski 1992] Tests of paraprotein levels and bone marrow examinations as standard methods of tracking disease progress for clinical purposes are, in this view, looking at the wrong target. Indeed, it is not impossible that useful treatments for multiple myeloma have already been tried and discarded because they did not produce a prompt effect on the plasmacytes! [Bergsagel 1995]

Second, the theory in question describes multiple myeloma as a two-stage disease, in which malignant B-cells in the blood "seed" the bone marrow with clonal plasmacytes. If we cannot stop the B-cells, can we make the bone-marrow environment less favorable to development of the plasmacyte population? [Caligaris-Cappio 1992] Empirical approaches to therapy for the disease seem to converging along this line.

Cytokines and Their Effect on Multiple Myeloma

Cytokines are protein hormones used by the body for intercellular communication. A subset of these called lymphokines plays a key role in control and coordination of the immune system.

The crucial cytokine for multiple myeloma is interleukin-6 (IL-6). In the normal action of the human body, IL-6 stimulates differentiation of B-cells into plasmacytes. IL-6 is released in response to inflammation or infection, and in turn stimulates formation of C-reactive protein (CRP) by the liver.

Evidence indicates [Klein 1990] that IL-6 is important, if not essential, for proliferation of MM cells. High serum levels of IL-6 correlate with disease activity. IL-6, which is expressed by cells such as monocytes, and especially by the stromal (support) cells of the bone marrow, is known to be overproduced in myeloma patients. In addition to promoting plasmacyte growth directly, IL-6 may also promote bone resorbtion, a major complication of multiple myeloma. [Klein 1992]

A controversy exists as to whether multiple myeloma cells are capable of making their own IL-6. Myeloma cell lines have been established which have this autocrine production capability; however, it is not clear that these in vitro cultures are representative of in vivo cell populations. It appears that there may be patient-to-patient variation, in which some tumors show autocrine IL-6 generation, some don't. [Kawano 1988; Hitzler 1991] It is also possible that autocrine IL-6 production develops only late in the course of the disease.

It appears that in most cases myeloma cells are dependent on IL-6 produced by the stromal (support) cells in the bone marrow. The myeloma cells have been shown to induce IL-6 secretion from the stromal cells by adhesion; actual physical contact is necessary. [Anderson KC 1995] There is evidence, though, that IL-6 induces differentiation, not proliferation. [Epstein 1995] Epstein also suggests the hypothesis that circulating IL-6/IL-6R complexes support myeloma cells that cannot express IL-6R themselves.

A recent report [Ballester 1994] challenges the conventional wisdom on IL-6. This study found higher IL-6 concentrations in MM patients' bone marrows, as compared to controls. IL-6 was positively correlated with IgG production, but negatively correlated with MM cells in culture. IL-6 was also negatively correlated with beta2M. Patient survival did not correlate to IL-6 levels. This work may contrast to previous studies because the authors examined IL-6 levels in bone marrow, rather than serum IL-6.

Another recent report [Hansen 1994] notes that serum IL-6 assays are complicated by the fact that much of the cytokine is bound in high-molecular-weight complexes; it appears that these may involve IgG autoantibodies, which apparently can be present in both healthy and diseased persons. It is also reported [Klein 1995] that much serum IL-6 is bound to soluble IL-6 receptor.

A recent review [Klein 1992] covers cytokine effects on multiple myeloma. It appears that GM-CSF, IL-3, IL-5, and G-CSF synergize with IL-6 to promote myeloma growth (for recent support, see [Abken 1992]).

*---> The use of G-CSF and GM-CSF after chemotherapy to reduce neutropenia may have the drawback of stimulating the disease. Klein is particularly concerned about the use of G-CSF [Klein 1992]. In fact it is asserted that use of G-CSF can dramatically stimulate tumor growth [Klein 1995 and cited refs].

Furthermore, alpha interferon induces autocrine production of IL-6 by myeloma cells in vitro! This raises questions about the use of interferon in maintenance therapy; see below.

On the other side, gamma interferon (IFN-gamma) inhibits the effect of IL-6. Also inhibiting IL-6, at least in vitro, is IL-4. [Herrmann 1991]

In multiple myeloma, all roads seem to lead to IL-6. Theory and basic research point out the crucial importance of this cytokine; empirical results from therapy and studies of diagnostic methods converge to the same point, as IL-6 levels turn out to account for phenomena previously unexplained. In particular, it is now known that corticosteroids suppress the disease by inhibiting formation of IL-6. It is therefore helpful to summarize the key factors which seem to affect this control parameter for the disease.

Favorable Unfavorable Unclear

IFN-gamma G-CSF, GM-CSF IFN-alpha

IL-4 TNF IL-1-beta

IL-2? IL-3

IL-5

infection

inflammation

However: It should be kept in mind that IL-6 probably influences the disease only at the level of the abnormal plasmacytes. It is not clear that this cytokine has any effect on the actual malignant B-cells. Thus methods which influence IL-6 ultimately can have only a palliative effect on the disease.

The Virus Connection in Multiple Myeloma

A recent study [Rettig 1997] found that Kaposi's Sarcoma-associated Herpes Virus (KSHV) infects, not the myeloma cells, but the stromal dendritic cells in myeloma patients. Normal controls, and patients with other leukemias, did not have KSHV infection. However, 2 of 8 MGUS patients did. KSHV was also found in Waldestrom's Macroglobulinemia patients. It should be noted, however, that there are conflicting reports whether KSHV is actually present; studies find that antibodies to KSHV are not more common in myeloma patients; and epidemiological connections between KSHV and MM are not what would be expected from a causal agent [Rettig 1997a].

Since only about 1-2% of the general population are seropositive for KSHV, Rettig et al argue that a causal connection of some sort between KSHV and MM is probable. It is noteworthy that the KSHV virus produces a protein which is homologous to IL-6, and that this vIL-6 has activity in humans. Moreover, the virus produces a bcl-2 analog.

The implications of this discovery could be profound but are not yet known. Other virus connections may also be found. An anecdotal report suggests that hepatitis C virus may be capable of inducing myeloma [Berte 1997].

STAGING METHODS, TRACKING THE DISEASE, AND PROGNOSIS

Multiple myeloma is "progressive," in the current medical euphemism; ie, incurable and fatal. Long-term survival is quite rare, though some patients have lived over twenty years. A survey by Polish authors [Kraj 1991] gives 15% survival at five years and 4% at ten years. A Japanese study [Togawa 1993] finds 3.3% survival at ten years. More recently, a Slovakian group [Sakalova 1994] claims 15% survival at ten years by use of aggressive chemotherapy. Survival statistics must be viewed with some caution, as inclusion of patients with MGUS or "smoldering myeloma" may bias the results.

Typically a patient population can be reasonably approximated by an exponential decay function. Median survival (the halflife of the exponential) with modern treatment is around 2.5 years; this has not changed for decades. (There are claims that this is markedly extended by BMT, or by use of interferon in maintenance therapy, but see below.) Graphing survival curves from different cohorts, improvement is evident [Alexanian 1997]. However, the curves are becoming convex, not concave. This is suggestive of the age-related death curve, with a maximum at about 12 years instead of the 85 for old age, and implies that treatment is not dealing with some cause of the disease.

In general, oncological staging methods overemphasize prognosis and expected survival times, reflecting the traditional obsession with "how long has he got to live?" They tend to neglect characterization of specific disease parameters that would be useful in planning treatment. Particularly in the case of cancers such a multiple myeloma which cannot be treated by surgery, there is a sort of balancing effect: Those cases with the fastest-growing tumors are also most responsive to chemotherapy. Thus it has even been asserted [Marmont 1991] that survival times in multiple myeloma are essentially independent of the aggressiveness of the disease.

An extensive study [Durie 1990] indicates that serum beta-2 microglobulin can be used to establish prognosis at the time of initial diagnosis. The most effective method, it was asserted, is combination of beta2M with age.

It should be noted that kidney failure causes beta2 microglobulin to rise. As kidney failure has a strong negative effect on prognosis (or does it? this has been challenged [Alexanian 1990; but see Blade 1995]), this may account for all or part of the effects found. Beta2 microglobulin is expected to rise linearly with serum creatinine, reaching 20 mg/L when creatinine is about 10. Any point above this line represents the myeloma, it is said [Alexanian 1997].

It should also be noted, when using beta2M as a prognostic indicator, that treatment with interferon raises beta2M levels.

Results were as follows:

At Diagnosis: Median Survival:

beta2M < 6 mg/L and age < 60 > 48 months

beta2M < 6 mg/L and age > 60 33 months

beta2M > 6 mg/L and age < 60 25 months

beta2M > 6 mg/L and age > 60 20 months

It appears that no longitudinal study has been done looking at beta2M during treatment. However, Barlogie tests for beta2M after induction but before ABMT, and then again before a second ABMT; he told me that there is little change between the two measurements. He sees a poorer prognosis with beta2M > 2.5.

Because IL-6 is apparently crucial to the progress of the disease, one might logically use concentration of this lymphokine as a staging variable. Direct measurement of IL-6 is somewhat difficult. A Japanese group [Yamagishi 1992] showed that in normal individuals serum IL-6 is below 3 pg/ml. In MM patients higher values, averaging around 10 pg/ml, are seen, but there is wide variation. (Note, however, that in a more recent study, much higher levels, around 250 pg/ml, of serum IL-6 were found in multiple myeloma patients [DuVillard 1995]). IL-6 levels, however, correlate (r around 0.5) with C-reactive protein (CRP), an easy and routine test. Confirming this, CRP levels have been found to reflect activity of the disease [Dubost 1991].

This is a particularly valuable result, as nobody else seems to be looking for a more effective way of tracking the disease. In general, the electrophoresis spike is used on the assumption that serum paraprotein correlates with disease progress. However, this is subject to some systematic error when corticosteroids (which have a catabolic effect) are used in treatment. Furthermore, it is not clear that paraprotein production is precisely proportional to tumor burden; indeed, as mentioned elsewhere, there is reason to believe that the disease can become nonsecretory in its advanced stages. Direct measurement of tumor burden can be attempted by sampling the bone marrow. However, the percentage of plasmacytes can vary from one site to another.

A staging system based on a combination of beta2M and CRP has recently been suggested [Bataille 1992]. These two variables are claimed to be independent, leading to the following classification scheme and prognosis:

At Diagnosis: Median Survival:

beta2M and CRP < 6 mg/L 54 months

beta2M or CRP > 6 mg/L 27 months

beta2M and CRP > 6 mg/L 6 months

Besides CRP, another acute-phase protein, neopterin, has been correlated with prognosis. Levels were about 5 nmol/L in controls, and around 11 nmol/L in MM patients. Values over 11 were associated with median survival of 20 months; below 11, median survival was 64 months. [Boccadeoro 1991]

Serum IL-2 is another possible prognostic indicator. [Cimino 1990] Specifically, serum IL-2 > 10 U/ml was associated with much longer survival. These authors found an inverse correlation between IL-2 and beta2M.

Serum lactate dehydrogenase has also been advocated as a prognostic indicator [Dimopoulos 1991]. High (> 300 U/L) levels were associated with short survival. Note that treatment with GM-CSF can raise LDH levels.

A longitudinal study of CD4+ and CD8+ T-cell counts in myeloma patients [Hicks 1989] found correlations of these measurements with patient prognosis. Specifically, the percentage of CD4+ cells was a crucial factor; the lower this number, the higher the likelihood of relapse. A review [Kyle 1994] points out a similar result, in which an absolute count of less than 700 E6/L of CD4+ T-cells was associated with shorter survival.

Other cell-classification criteria have been proposed. High proportions of circulating plasma cells are a negative prognostic factor. Counts of plasmablasts (immature plasma cells) are another strong negative factor; this test is easy to do. Counts of CD38+ (> 450 E6 /L associated with poor survival) and PCA1+ lymphocytes have been used [Omede 1990]. The presence of CALLA-positive cells in the bone marrow is said to correlate with aggressive disease [Durie 1985].

ONCOGENES IN MULTIPLE MYELOMA

Recent work from Barlogie's group at Arkansas [Tricot 1995] investigates genetic abnormalities. Abnormal cytogenetics were found in 39% of their patient sample; however, unfavorable prognosis was associated only with karyotypes with changes on chromosomes 11 or 13 (or, worst, both). It increasingly appears, however, that oncogenesis occurs as the variable regions of the B-cell undergo hypermutation, and a translocation jams an oncogene onto chromosome 14 into the mutation region. 14q+ mutations were found in 65% of MM patients [Dalla Favara 1997].

As noted below, there is reason to believe that the oncogene bcl-2 plays a role, perhaps a dominant role, in myeloma. However, a recent paper points out that another oncogene, retinoblastoma (rb) is involved. Mutations or abnormalities in rb have been found in up to 70% of MM patient. [Urashima 1996] It has also been found that about 50% of myeloma patients have mutations in the gene ras at diagnosis. Mutant p53 seems to appear mainly in late myeloma, and it is associated with resistance to dexamethasone [Van Ness 1997]. A new oncogene [isolated from my bone marrow!] was recently discovered in MM, belonging to the FGF family, called FGF-X [Berenson 1997] Two systematic studies [Brown 1994; Joshua 1997] of oncoproteins in myeloma patients found the following percentages of patients with abnormally high expression. Note the higher numbers from the more recent study, which reflects improvements in technology for detecting oncogenes.

Oncoprotein %: Brown 1994 Joshua 1997

c-myc 53 39

Rb 28

bcl-2 28 41

c-fos 27 44

p53 wild 24

p53 mutant 23 20

c-neu 13 35

pan-ras 13 24

The assertion by Michaeli (see below in discussion of HMBA) that bcl-2 is the crucial oncogene in myeloma receives mixed support in the literature. A study in Sweden found bcl-2 expression in 55 (87%) of a sample of 63 patients. Failure to respond to alpha-interferon treatment was associated with bcl-2 expression; however, failure to respond to MP was not. [Sangfelt 1995] Another study found that "in all patients the large majority of plasma cells expressed bcl-2." However, surprisingly, patients with long survival had higher percentages of bcl-2+ plasma cells than did short-survival patients. [Ong 1995] Compare this, though, to a study of drug resistance factors [Sonneveld 1997]:

Disease bcl-2 PGP LRP

MGUS +/- - -

MM + + +

PCL +++ - +

A further complication is introduced by the role bcl-2 plays in modulating T-cell activity. [Massaia 1995] In MM patients activated T-cells appear which attempt to attack the disease. However, these T-cells undergo early apoptosis due to underexpression of bcl-2. This suggests that anti-bcl-2 therapeutic strategies may hinder the body's ability to mount an immune response to the disease.

Summing up, the evidence to date suggests that no single oncogene is responsible for myeloma. It may be that the original oncogenic event is a failure of the normal mutation process in B-cells resulting in a chromosome 14 defect. It seems that other oncogenes may accumulate as the cancer evolves. It is interesting to note that time to relapse from plateau phase is an exponential with half-life 18 months, which suggests a random oncogenic event, probably genetic [MacLennon 1997]. Note that the half-life for MGUS--->MM is certainly far longer, though, with about 1% progression per year [Back 1997].

TREATMENT OF MULTIPLE MYELOMA

The objective of treatment is to obtain a remission, one hopes a "complete remission" (CR). (But see Pilarski's speculation about plateau phase, above.) It should be kept in mind that workers in the field are not in agreement on what constitutes a CR and conflicting definitions are used. [Gore 1989] Commonly a 50% or 75% reduction in paraprotein is considered a "response" or a "partial remission" (PR). A complete remission may be claimed if the paraprotein completely disappears and plasma cells are in normal proportion (1-2%) in the bone marrow; but some authors are less strict. It is not clear that debates over the proper definition of remission are relevant. Thus it is asserted [Joshua 1994] that the extent of reduction in paraprotein does not have prognostic significance; rather "entry into plateau phase and the duration of plateau phase . . . determines survival." Another study [Shimizu 1997] indicates that percentage reductions in paraprotein correlate poorly with survival; the real indicator is absolute paraprotein at the nadir from initial treatment. They found:

Paraprotein after Therapy Median Survival

< 2.0 g/dL 40.4 months

2.0-4.0 g/dL 30.2 months

> 4.0 g/dL 13.9 months

As discussed above, based on current knowledge it appears that treatment of multiple myeloma has been handicapped by an inadequate theoretical basis. As a result, therapy may have been misdirected. The plasmacytes, which appear to be mainly only symptomatic, were attacked vigorously; while the actual malignant B-cells, the cause of the disease, were not even perceived as a problem and no doubt were killed only as an accidental by-product of therapy. Nonetheless, as shown by the most recent review of therapies for multiple myeloma, clinical tests have not begun to catch up with theory [Child 1994].

The empirically effective methods of chemotherapy turn out, frequently, to have targeted IL-6. While there is some potential for improved therapies based on intentionally applying new knowledge about this cytokine (eg, use of antibodies to IL-6, as discussed below), the point of diminishing returns has probably been reached with this approach. Suppression of IL-6 production can suspend but not cure the disease; and because IL-6 plays an important part in normal immune function, long-term interference with its secretion is likely to cause serious side-effects.

A significant problem with chemotherapy for multiple myeloma is immunosuppression. All the standard chemotherapeutic agents are immunosuppressive. This is a serious drawback because the disease itself results in immune system disfunction. The B-cell system is crippled, for reasons which are not clear, with a resulting increased susceptibility especially to bacterial infection.

One conjecture is that the T-cell system, seeing excessive activity in the humoral system, down-regulates B-cells. This might correlate with Maitland's hypothesis (see above) that the disease is somehow self-regulating. It is also interesting to note that NK cell counts are elevated in newly diagnosed myeloma patients [Jackie Kornbluth, personal communication 1995], suggesting an attempt by the T-cell system to mount an immune response against the malignancy. This later disappears, probably due to the neutropenic effects of chemotherapy.

At the same time, T-cells are reduced in myeloma patients, accompanied by an imbalance in CD4+ T-cells (too low) and CD8+ (too high). That is, helper T-cell function is reduced, while suppressor T-cell function is excessive. Gamma interferon and IL-2 tend to rise in myeloma patients; high levels of the latter tend to correlate with survival, suggesting that T-cell activation is important in controlling the disease. [Hoover 1992] It should be noted that there is evidence that chemotherapy, at least at high doses, can damage the thymus. [Beschorner 1978]

In addition to the direct hazard of infection--as previously noted, infection is the leading cause of death in myeloma patients--there is evidence that infection may pose an indirect threat by stimulating the disease. [Klein 1992] In the normal course, infection causes IL-6 levels to rise, and this of course stimulates progression of the myeloma.

Conventional Chemotherapy

Standard chemotherapy regimes for multiple myeloma rely on three types of agents, alone or in combination:

* Corticosteroids: prednisone (P), methylprednisone (MP), or dexamethasone (D; "decadron"). These compounds have effects like cortisone, but much more powerful.

* Alkylating Agents: melphalan (M; "alkeran") or cyclophosphamide (C; "cytoxan"). Highly reactive compounds, related to the "mustard gas" used in World War I, these agents attack the DNA in rapidly growing cells and kill them.

* Alkaloids: vincristine (V) and adriamycin (A; "doxorubicin"). These are natural plant products. Like the alkylating agents, they are cell-killing ("cytotoxic") but with a somewhat different mechanism of action.

The corticosteroids function, it is now believed, by inhibiting expression of IL-6 mRNA. Presumably the other agents function due to their general effect on dividing cells. However, cases initially resistant to dexamethasone are generally also resistant to other therapies, which is hard to explain. Moreover, patients who relapsed after dexamethasone treatment were if anything more responsive to other therapies for second-line treatment.

Speculation: Though cytotoxic agents do reduce the myeloma plasmacytes, perhaps they do not attack them directly, but kill the bone-marrow stromal cells on which the plasmacytes depend. It is notable that the most effective cytotoxic agent against myeloma, melphalan, is notorious for its destructive effect on bone marrow. I'm told, though, that stromal cells are not particularly fast-growing [Brian Durie, personal communication, 1995].

Responses to standard therapies in previously untreated patients have been compared [Alexanian 1992]:

Method Overall Response Rate

MP about 45%

VAD about 60%

D only 43%

More recently an extensive study [Anderson 1995] found a response rate of 80% with VAD for previously untreated patients; this dropped to 50% for relapsed or refractory patients. Assorted other multidrug combinations (VBMCP, VMCP/VBAP, etc) have been tested, but a review of the available evidence indicates that they offer little if any advantage. [Mandelli 1992] One study [Paccagnella 1991] indicates that intermittent therapy works as well as continuous treatment. The idea is to get a remission, stop till relapse occurs, then use the same drugs again. Survival is said to be as good and quality of life improved.

Bergsagel [1995] points out that there is little or no evidence that vincristine is active against multiple myeloma. Use of this extremely toxic drug in such regimes as VAD is, he says, "surprising." This argument is apparently making an impression, and trials are being conducted of regimes that could replace VAD, such as etoposide-dexamethasone and idarubacin-dexamethasone.

All chemotherapeutic regimes against multiple myeloma eventually fail due to development of resistance. Recently it has been shown that multidrug resistance ("MDR") tends to develop in response to chemotherapy. [Grogan 1993]. Vincristine and adriamycin are particularly potent in inducing drug resistance. (This has been associated with an increase in the anti-toxin pump P-glycoprotein, but a recent paper finds that adriamycin and etoposide upregulate bcl-2. [Tu 1996]) This may account for the fact that VAD, though the most effective regimen as salvage therapy, shows no advantage in survival when used as front-line therapy. [Alexanian 1990]

Various methods are under investigation for reversing multidrug resistance. [Dalton 1992] The use of verapamil and quinine in combination with VAD, with modest success, has been described. [Lehnert 1991; Salmon 1991] Verapamil, a calcium blocker, has serious cardiotoxicity. However, it is the (R) enantiomer of the drug which has the anti-MDR effect, and the (S) enantiomer which is a calcium blocker; so use of (R)-verapamil, instead of the racemic mixture, may be safer. However, preliminary results indicate that (R)-verapamil is not particularly effective. [Salmon 1995] Cyclosporin has also been used to prevent MDR. [Sonneveldt 1992] The Sandoz drug PSC-833, related to cyclosporin but said to be less toxic (it is not immunosuppressive and not nephrotoxic), is now under development. [Sonneveld 1995] A phase II trial of VAD + PCS-833 is in progress. Another approach involves use of chimeric antibodies against P-glycoprotein [Hamada 1990]. A difficulty here is that P-glycoprotein probably plays an important role in protecting certain normal cells from toxic compounds. It is now proposed that anti-resistance drugs should be used early in the disease, to prevent development of resistance, rather than overcome it [Dalton 1997].

On the other side of this question, Bergsagel points out that multidrug resistance is not a major problem with alkylating agents. He believes the real problem is "kinetic resistance," which is simply a matter of the growth rate of the disease increasing after each relapse. [Bergsagel 1995] However, evidence indicates that alkylating agents may be resisted by glutathione [Sonneveld 1997].

Various new agents are being tested for multiple myeloma. The compound fludarabine was found to be ineffectual in this disease. [Kraut 1990] 2-Chlorodeoxyadenosine (2-CDA) has recently shown great promise for treatment of Waldenstrom's macroglobulinemia; however, Sloan-Kettering says it is not useful for multiple myeloma. Nucleoside transporter levels in myeloma cells are quite low; this probably accounts for the ineffectiveness of these drugs [Joshua 1994].

*---> If nucleoside transport through the cell wall into myeloma cells is inefficient, must they not be synthesizing nucleosides more actively than normal cells? They need a lot of DNA and RNA, after all. Could this be an exploitable metabolic difference?

Taxol has shown promise against multiple myeloma in vitro [Nguyen 1994]; however, it is said to be disappointing in clinical practice [Anon 1994], and a study at Mayo found it too toxic at the needed dosages [Miller 1995]. (But see below for combination with differentiation agents.) Imexon (2-oxo-4-imino-1,3-diazabicyclo[3.1.0]hexane) is said to have potential based on in vitro studies [Hersh 1992]. This compound is not effluxed by PGP, is not myelosuppressive, and does not bind to DNA. Apparently it operates agains myeloma by depletion of cysteine and glutathione [Salmon 1997] Etoposide (VP-16) seems to work well, at least in some patients. Topotecan, used as a third-line therapy in patients who had failed other drugs, got a 25% response rate with median survival 21 months. [Salmon 1995] There is also strong interest in idarubacin (Zavedos). This is an anthracycline related to adriamycin. However, unlike adriamycin, it can be taken orally, and it is said to be less toxic. [Franklin 1994] Another cytotoxic compound, vinorelbine, seems to have at least slight activity against myeloma [Salmon 1997]. PEG-L-asparaginase, in a phase II clinical trial, showed some activity against refractory myeloma [Hussein 1996]. A vitamin D derivative has indicated some activity in in vitro studies [Puthier 1996]. A clinical study is starting at May Clinic to use the steroid DHEA to inhibit progression of MGUS to MM [Lust 1997].

Side Effects of Chemotherapeutic Agents

A review [Gurtler 1980] lists side-effect frequencies of drugs, including busulfan, cyclophosphamide, and vincristine, and offers specific suggestions for countering them. Nausea and vomiting are of course common, along with diarrhea, hair loss and mouth sores. Among major long-term effects are the following:

Immunosuppression: All of the standard chemotherapeutic agents--alkylators, alkaloids, and even steroids--are immunosuppressive. Melphalan is notoriously damaging to the bone marrow. Suppression of platelet formation (thrombocytopenia) which can lead to uncontrolled bleeding, as well as of white blood cells (neutropenia) is common. Immune function normally returns after treatment is stopped, but, particularly with heavy doses, the bone marrow and/or stem cells may never completely recover.

Carcinogenicity: All alkylators and many other chemotherapeutic agents are carcinogenic. Incidence of pharmagenic cancer is a few percent. Usually it is leukemia, but some other types of cancer also occur. Cyclophosphamide, for instance, is associated with bladder cancer.

Lung Damage: A review of respiratory complications in chemotherapy [Muggia 1981] states: "Pulmonary fibrosis is rare with alkylation agents, except for busulfan." The incidence of lung fibrosis due to busulfan is a subject of disagreement among authorities. AMA Drug Evaluations says "rare"; Remington's, "uncommon." USPDI, however, puts this fatal complication in their intermediate category, "less frequent." It should be noted that it is sufficiently common to have acquired a nickname, "busulfan lung." The only attempt at a quantitative estimate [Collis 1980] indicated that busulfan killed about 2.5% of the patients who used it.

Gonad Damage: Sterility, in both men and women, is routinely expected as a side-effect of cytotoxic chemotherapy. Additional effects of damage to the gonads should not be assumed to be absent. An informal survery of BMT long-term survivors found 50% of them admitting to permanent reduction of sexual capacity due to the treatment [Anon 1993]. It should be noted that this non-random sample consisted of persons highly positive to the therapy whose bias, if any, was toward minimizing its drawbacks.

A review [Waxman 1983] asserts that, in men, testosterone and luteinizing hormone levels return to normal after cytotoxic chemotherapy, though FSH and prolactin may be elevated. However, another review [Hien 1980] indicates that several drugs (notably busulfan, cyclophosphamide, vincristine, and prednisone) have gonadal toxicity over and above the expected aspermia. A third review focuses only on fertility effects [Shalet 1980].

For busulfan, Remington's lists impotence even ahead of sterility as a side-effect. AMA Drug Evaluation and USPDI say testicular atrophy may occur.

Brain Damage: Damage to the brain or CNS is apparently rare as a chemotherapy side-effect. Nonetheless, loss of memory or concentration is commonly reported by BMT survivors [Anon 1993], and a more systematic study from the Seattle group [Partii 1989] confirms that a problem exists.

Vincristine is associated with peripheral neuropathy, which is generally reversible, though slowly.

Heart Damage: Cardiotoxicity is well known as a side effect of adriamycin, though incidence is said to be rare. Some cardiotoxicity may occur with cytoxan.

Bone Damage: The steroids, particularly dexamethasone, tend to cause bone loss.

Kidney Damage: Chemotherapeutic agents normally do not directly damage the kidneys. However, in patients with kidney damage the dose of melphalan must normally be decreased because clearance of the drug is slowed.

Protective Measures against Chemotherapy Side Effects

Beta-carotene at very high levels (400,000 U/day) dramatically reduces oral mucinosis due to chemotherapy. [Mills 1988] It should be noted that the therapy group stopped use of carotene after a few weeks, and that oral mucinosis then started to rise. It therefore seems desirable to continue use longer. Whether the protective effect of beta-carotene extends to the rest of the GI tract was apparently not investigated. A related point is suggested by the fact that standard parenteral solutions are especially low in this nutrient. [Clemens 1990]

One report indicates that hair loss caused by adriamycin can be reduced or prevented by taking vitamin E [Wood 1985]. The dosage is 1600 IU per day, and should start one week before treatment. Vitamin E may also be effective against the cardiotoxicity associated with this agent.

Another nutrient is said to be useful for preventing hair loss: vitamin D. Topical application of 1,25(OH)2D3 has been claimed to prevent alopecia due to cytoxan. [Jiminez 1995] This vitamin is known to inhibit myeloma cell growth, so it's worth taking.

The importance of glutathione metabolism in chemotherapy has been reviewed [Arrick 1984]. Particularly notable is the observation that elevating glutathione levels by addition of cysteine or its derivatives to the diet improves the therapeutic index of certain cytotoxic agents. Specifically, the toxic side effects of cyclophosphamide and adriamycin are diminished while antitumor activity is unaffected. Along somewhat the same lines, use of MESNA in combination with cyclophosphamide is a common protective measure to prevent bleeding from the bladder.

A brief report from a Belarus research group [Trebukhina 1996] suggests that vitamin B-1 (thiamine) may be of significant value as an adjunct to chemotherapy. In work with rats, B-1 was found to increase the therapeutic effect of cyclophosphamide or vinblastine, while reducing leukopenia. Extrapolation to human beings suggests a dosage of around 300 mg/day would be effective.

It is asserted that low-density lipoprotein (LDL) is decreased in at least some cancers, including MM, because cancer cells have more LDL receptors due to their increased need for lipids for building cell walls. Preliminary clinical studies indicate that giving carmustine in combination with microemulsions resembling LDL reduces toxicity and may also increase effectiveness [Hungria 1997].

Treatment of Myeloma Symptoms

Symptomatic relief is also an objective of therapy. A major interest is use of bisphosphonate drugs to minimize bone loss. The early versions, such as etidronate and clodronate had limited effectiveness. The second-generation bisphosphonate pamidronate ("Aredia") seems to be highly effective, though it must be given in monthly IV infusions. It can halt, but probably not reverse, bone loss. Clinical studies indicate that clodronate does not prolong survival, but there is some reason to believe that pamidronate might. For instance, an in vitro study found that pamidronate reduces IL-6 production by bone marrow stromal cells from myeloma patients [Savage 1996]. Moreover, in a mouse model, tumor growth was inhibited by pamidronate [Mueller 1996]. Fosamax is also being used for myeloma; it can be taken orally but side effects have given it a bad reputation among patients. A third-generation bisphosphonate, zoledronate, looks promising from its phase I clinical trial [Berenson 1996].

Another hazard for myeloma patients is myeloma kidney. Kidney damage may be precipitated by hypercalcemia, which is common in myeloma; or by formation of "casts" from the paraprotein. Kidney failure may or may not be reversible; if it is not, long-term dialysis is required. Currently about 2,000 myeloma patients in the U.S. are on dialysis; median survival for this patient subgroup is about one year. So far two patients have been treated with kidney transplants; both died.

Bone Marrow Transplant/Stem-Cell Rescue

As chemotherapy has reached the limits of its effectiveness, oncologists have turned to the simple expedient of increasing the dosages used. The limiting toxicy for most chemotherapeutic agents is destruction of the bone marrow, with its blood-creation (haemopoiesis) and immune-system functions. The logical approach is to take some bone marrow; treat the patient with a lethal dose of chemotherapy, which completely ablates the bone marrow; and return the marrow, which can then "re-graft" and restore haemopoiesis and immune function. This is the misnamed "bone marrow transplant" of the autologous sort. It is also possible to use bone-marrow from a donor (allogeneic transplant). In this case, there needs to be a good HLA match, or graft-vs.-host-disease (GVHD) will result as the new immune cells recognize the host body as foreign and attack it. It is also possible to use the haemopoietic "stem cells" from the peripheral blood. However, the basic issue is the same in all of these methods: Killing the cancer by use of an extremely high dose of chemotherapy, followed by "rescue" of the patient by re-grafting the bone marrow. ("Kill him, then bring him back to life.") This subject has been reviewed repeatedly. [Jagannath 1992; Tura 1992; Fermand 1992] The risk associated with the procedure is substantial, and the cost is frightful--the minimum is generally about $150,000, and it is not impossible to spend $500,000 on a BMT.

In general, BMT or stem cell transplant seems to give a high ratio of complete remissions. It is even possible that some patients are "cured," though most relapse within a few years. Barlogie's group has been the strongest advocate of BMT, and he does double and even triple BMTs. Response is better with allogeneic BMTs, probably because some anti-cancer effect is obtained by GVHD effects in which the new immune cells can perceive the cancer cells as "foreign" and attack them. (This is the basis of the Jones pseudo-GVHD method, discussed below.) Unfortunately, mortality from allogeneic transplants typically runs around 50%. Autologous transplants are much safer, but the patient's bone marrow, which is returned, may contain tumor cells that can contaminate the bone marrow and re-seed the blood with the cancer. Various methods have been advocated for "purging" the bone marrow, including of course use of purified stem cells. Again, though, there is controversy; the Barlogie group is inclined to think that BMTs fail due to inadequate myeloablation, not recontamination (Jagannath 1990).

There is considerable controversy over whether BMT actually cures patients. That BMT gives much higher complete remission (CR) rates, and longer median survival, than conventional therapy is unquestionable. However, BMT protocols insist on relatively healthy and young patients, particularly for allogeneic BMTs; this non-random selection may account for the better results achieved. A recent prospective study seems to indicate that this is in fact the case; when patients suitable for BMT were treated with conventional chemotherapy, they achieved a median survival of 5 years [Blade/Miguel 1995]. On the other hand, an even more recent study finds just the opposite [Attal 1996]. Two hundred patients (under age 65) were randomized to either BMT or VMCP/VBAP. The BMT group had distinctly better results. Event-free survival was 28% for the BMT arm, 10% for the chemo arm, at five years.

Recently a new twist has been added, in which the donor for an allogeneic BMT was first immunized against the patient's cancer cells. The concept is interesting, but as yet the method can claim only one anecdotal report--and there is no evidence that any therapeutic advantage resulted. [Kwak 1995]

Cytokines in Myeloma Therapy

Use of alpha interferon (IFN-alpha) as "maintenance therapy" for MM is now becoming standard practice. The primary therapeutic rationalization is that IFN-alpha prolongs the "resting" phase of cell division. However, IFN-alpha also increases NK activity; and, in vitro, reduces paraprotein expression. This subject has been reviewed [Avvisati 1992].

The available evidence suggests that IFN-alpha prolongs remissions ("plateau phase") but does not improve overall survival. This suggests that Klein's argument [Klein 1992] is well-taken. He takes the position that IFN-alpha does no harm in maintenance therapy, because during the plateau phase there are few dividing myeloma cells to be encouraged. However, he warns that if the disease relapses, the IFN-alpha could then stimulate it. Summarizing recent work in the field, Klein points out that in one study IFN-alpha stimulated tumor growth in up to 30% of patients at diagnosis, and 50% of treated patients; in other patients, it had an inhibitory effect or no effect. [Klein 1995 and cited refs] It has also been observed (in vitro) for interferon to inhibit production of paraprotein without affecting myeloma cell proliferation. It should be noted, however, that a recent study finds that interferon, though prolonging the plateau phase, does not prolong survival even though not given after relapse. [Westin 1995] The emerging consensus seems to be that IFN-alpha either "covers up" the indications of relapse, or actually accelerates the disease during relapse.

It might seem logical (see above) to use gamma-interferon to treat myeloma. However, this agent has proved too toxic [Bergsagel, private communication, 1995].

Other approaches rely on exploiting the disease's dependence on IL-6. As previously noted, the effectiveness of corticosteroids in treating multiple myeloma is believed to derive from their ability to inhibit IL-6 expression. A related approach is use of retinoic acid, which appears to down-regulate IL-6 receptors [Sidell 1991]. Retinoic acid has been found to exert a synergistic effect with interferon [Kumar 1992]. The use of retinoids in cancer therapy has been reviewed several times. [Tallman 1992; Bollag 1992; Smith 1992] In general, however, results with clinical trials of retinoic acid for multiple myeloma have not been encouraging. A recent report [Niesvizky 1995] found severe hypercalcemia caused by treatment with all-trans retinoic acid, and serum IL-6 levels were increased, apparently in response to the reduction in IL-6 receptors. The most recent approach uses higher doses of retinoic acid on an intermittent schedule; results are not yet in. Reducing IL-6 production with inhibitors of prostaglandin E2 has been suggested [Klein 1992].

An obvious point of attack is monoclonal antibodies to IL-6. A study [Klein 1990] showed that moabs to IL-6 do indeed inhibit MM proliferation in vitro and also in vivo. Clinical results were more or less anecdotal but remission appears to occur. See also: [Klein 1991; Suzuki 1992; Brouet 1991; Hitzler 1991]. This approach is limited by the fact that in many if not most patients, IL-6 levels are higher, by an order of magnitude, than can be neutralized. [Klein 1995]

One could also attack the IL-6 receptor. This cannot function by itself; it is dependent on attachment to another protein called gp130. It has been suggested [Dunbar 1993] that flooding the body with a soluble gp130 analog might disable the IL-6 receptor.

A recent trial tested low-dose IL-2 in relapsed patients. [Peest 1995] (This might actually be considered a form of immunotherapy.) Of 17 patients, 6 had a positive response. In several other patients, on the other hand, the treatment appeared to accelerate the disease. Low-dose IL-2 has also been suggested as a "maintenance therapy."

IL-4, another cytokine, has also been investigated at Arkansas. The concept here is that IL-4 can increase the susceptibility of myeloma cells to attack by NK cells by upregulating CD-9 expression. Myeloma cells normally do not express CD-9, which is believed to be necessary for vulnerability to NK cells. NK cell activity is normal or even elevated in untreated myeloma patients. [Kornbluth 1995] Jackie Kornbluth told me that results in a Phase II trial of IL-4 were disappointing. There was no activity at low doses, and "bizarre toxicity" at high doses. [Kornbluth, personal communication, 1995] However, based on the theoretical model, use of this agent in relapsed or refractory patients whose immune systems have been damaged by chemotherapy would be expected to fail. It might yet prove effective as a first-line therapy.

Immunotherapy for Multiple Myeloma

With multiple myeloma, as with other cancers, immunotherapy seems most likely to have value as a supportive rather than primary measure. Once the tumor mass is highly reduced by other means, the immune system may be able to deal with it. Because multiple myeloma is itself a disease of the immune system, and is known to be accompanied by immunodeficiency, it is one of the less promising candidates for immunotherapy.

It has been suggested that the use of LAK cells or stimulation of NK cells might be effective [Hoover 1992]. However, a brief comment by Barlogie [3/93 UCSD stem cell conference] indicated that increased NK cell activity correlates with poorer results in multiple myeloma, and that Rosenburg's LAK technique fails.

Along other lines, however, work by Jones at NIH [Hess 1992; Yeager 1992] offers some very interesting results. He operates on the hypothesis that allogeneic BMTs produce better results (for those patients who survive) due to graft-vs-host disease (GVHD). The idea is that the residual tumor after high-dose chemotherapy consists of the most chemo-resistant cells; if one can get even a log 2 or so kill by immunological effects of GVHD, that may do the job. Jones followed up on the observation that even in autologous BMTs, about 5-10% of patients develop a sort of mild pseudo-GVHD, which is self-limiting and involves only the skin. T-cells against class II MHC are responsible (the effect doesn't happen with solid tumors, which don't express class II MHC much). This phenomenon develops from pre-thymic precursors; T-cell depletion helps, and an intact thymus is essential--but the thymus must be damaged. Loss of suppressor T-cells may be a factor.

After encouraging results in animal models, the Jones group turned to clinical trials. They give low-dose cyclosporin immediately after autologous BMT for a couple of weeks. Supplementing with alpha-interferon and low-dose IL-2 helps. About 70% of the patients get pseudo-GVHD, which lasts 1-5 weeks, and these patients tend to survive better. They are now going into phase III trials, and there is definite evidence for reduction in relapse rates. This method, combining the relative safety of autologous BMT with the higher CR rate of allogeneic BMT, looks extremely interesting. On the other hand, the procedure is highly empirical, classical "black magic," based on damaging the immune system just enough to turn out defective T-cells with just the right loss of selectivity and in just the right numbers.

Jones has been working with Hodgkin's disease, NHL, and AML. Whether his method could be generalized to multiple myeloma is now being tested in a clinical trial [Weber 1997]. GVHD was successfully induced but results do not look promising.

*---> Would it be possible to utilize the Jones pseudo-GVHD technique during the neutropenic period from conventional chemotherapy, without having to undergo a BMT?

A different approach to immunotherapy uses antibodies to CD3. This agent boosts T-cell activity, and the effect appears to be especially strong in multiple myeloma patients. A study indicates that the stimulated T-cells do attack the disease in vitro. T-cell stimulation was also demonstrated in vivo, but it is not clear whether any therapeutic effect was obtained. [Massaia 1993]

Another speculative approach might use antibodies to CD40 [Umlauf 1996]. Recently it has been found that the ligand (CD40L) is necessary for survival of B-cells during antigenic stimulation. It is notable that this antibody, an unusual case, may not have to be humanized for therapeutic use.

There is some speculation that myeloma may normally be "regulated" by the T-cells, and that progression of the disease occurs only because the malignancy eventually escapes from this regulation. Phil Greipp told me an interesting anecdote about one of his patients who developed a second spike; her first spike spontaneously disappeared, and the second was benign. [Greipp, personal communication, 1995] More recently it has been established that some myeloma patients have T-cells that are reactive to the myeloma clone, and that these patients have improved survival [Brown 1996].

A clinical trial of 12 patients with a vaccine approach is running. So far results are not encouraging [Massaia 1997].

Generalized stimulation of the immune system by vitamins and other nutrients is discussed below.

Differentiation Agents

Most normal plasmacytes live only a few days before undergoing apoptosis (programmed cell death). (However, the small fraction of plasmacytes that normally resides in the bone marrow consists of long-lived cells.) Obviously if this natural behavior could be restored to myeloma cells one would have a valuable treatment for the disease.

Most chemotherapeutic agents may be considered as apoptosis-inducing in some sense. [Hannun 1997] Steroids such as dexamethasone, as well as retinoic acid, induce apoptosis directly by modulating a pathway involving IL-6. Other agents, by damaging DNA, set off the cell's natural machinery for self-destruction, part of the body's defense against genetic damage. However, more subtle approaches are needed.

Hexamethylene bisacetamide (HMBA) has shown promise in vitro as an agent to cause apoptosis of myeloma cells. [Zhang 1994] A phase II clinical study is planned at Sloan-Kettering. However, I'm told [Durie, personal communication, 1995; Salmon, personal communication, 1995] that the compound has rather low activity. Nonetheless, in vitro results indicate that the anti-apoptosis protein bcl-2 is rapidly and effectively downregulated in myeloma cells treated with HMBA. Moreover, treatment with HMBA then results in classic apoptosis--even in cell lines that are resistant to dexamethasone-induced apoptosis. [Michaili 1995] HMBA, which has been used in Phase II trials for AML [Andreef 1992], is relatively non-toxic (it causes thrombocytopenia), but extremely heavy doses are required. It should be given by IV, as oral activity is poor. Far more potent analogs, such as suberic acid bishydroxyamide, have been developed, but they are still at the in vitro stage, though one is rumored to have reached animal studies. [Michaeli 1992; Breslow 1991]

A natural product called beta-alethine (beta-alanylcysteamine disulfide) has been found effective against a myeloma model in mice. [Knight 1994a] The authors argue that a structural similarity between beta-alethine and HMBA is relevant. This may be of interest, as beta-alethine is more potent and less toxic than HMBA. Still more potent is the N-CBZ derivative of alethine, which proved effective against syngeneic murine myeloma at 100 pg/kg. [Knight 1994b] The N-carboxy compound, vitalethine, is believed to be a key regulating factor for cell growth.

Along the same lines, following up an old report that arginine butyrate has anti-cancer activity, workers at Mayo Clinic are looking into phenylacetate and phenylbutyrate as apoptosis or differentiation agents. [Phil Greipp, personal communication, 1995] In vitro studies suggest that combination of phenylacetate or phenylbutyrate with taxol may be worth looking at [Hsu 1996].

Other Possible Medical Approaches to Therapy

Multiple myeloma is strongly susceptible to radiation. However, because of the extension of the disease throughout the body, whole-body irradiation is needed. This has been used for BMT but is too hazardous for therapy without rescue. Local irradiation can be used to deal with serious bone lesions, however. It would be interesting to investigate whether irradiation of the blood outside the body would be practical.

An interesting possibility which has received apparently no attention at all is thermotherapy. It is known that cancer cells are more susceptible to high temperature than normal cells, and heat has been used for therapeutic purposes. Multiple myeloma would seem to be an especially promising candidate for this approach, for if the malignancy is actually in the blood, it can be heated while out of the body.

Another approach to treating the blood is offered by the recent development of cell-separation machinery based on resins with bound antibodies. It appears that the malignant B-cells are CD19+; processing the blood through a column with attached CD19 antibodies could in principle remove the cancer cells. It is unlikely the removal would be 100% effective, of course. It is estimated that about 50% removal could be achieved [Berenson, personal communication, 1995] Of course, since normal B-cells are also CD19+, general immunodeficiency might result; but in myeloma patients the B-cells seem to be ineffective anyway.

Currently there is considerable interest in cancer therapy based on binding a radioisotope or other cytotoxic agent to tumor-specific antibodies. Recently it has been shown that a hyaluronate receptor, RHAMM, is expressed on the surface of multiple myeloma cells; this might provide a handle that could be used for an antibody approach. [Turley 1993]

Prospects for gene therapy for cancer in general, and myeloma specifically, are limited. However, a recent paper suggests that B-cells could be genetically modified to express a toxic compound, then re-infused. Proliferating into plasmacytes in the bone marrow, they would locally poison the MM cells. A primitive form of this concept was tested in mice. [Dilber 1996]

Palliative measures should not be neglected. One factor of no small importance is prevention or minimization of kidney damage. The use of plasmapheresis when paraprotein levels are high may be helpful here. A recent report [Siemasko 1996] finds that an immunosuppressive drug, leflunomide, inhibits the proliferation of B-cells, as well as secretion of IgG. This might be useful as a palliative measure. Moreover, the drug is found to inhibit pyrimidine synthesis. Since myeloma cells seem to be inefficient at uptake of nucleosides (as implied by the failure of 2-CDA treatment; see above), yet must have heavy needs for RNA in view of their intensive protein synthesis, this suggests another reason to try the drug against myeloma.

Nutritional Approaches to Therapy

There is widespread popular interest in nutritional methods for cancer prevention and treatment. In general the track record for various diets is only mildly promising. It is possible that some of these diets (most of which are vegetarian) can have a beneficial effect by starving cancer cells of the fats they need to build cell walls, or of other nutrients, especially B-12. Other approaches attempt to exploit the pH difference between cancer and normal cells or the presence of excess lactic acid in cancer cells.

It should be understood that nutritional approaches to cancer treatment may be radically different from nutritional approaches to cancer prevention. Once a cancer has developed, the problem becomes one of differential nutrition of cancer and normal cells. Because cancer cells are defective, they may be more dependent on certain nutrients than are normal cells. Thus high dosages of vitamins may actually encourage growth of the malignancy.

An instructive example is provided by the case of vitamin C, which may be contraindicated in multiple myeloma and leukemia. It was found that in one cell line of myeloma, proliferation was promoted by ascorbate [Park 1991]. The authors switched to leukemia, which can be cultured more easily, and found that the effect of ascorbate was case-dependent. In about 35% of the subjects, ascorbate promoted the cancer in vitro; in about 15%, it inhibited it. It is likely that some other nutrients may show a similar phenomenon. It should also be noted that high doses of vitamin C, by causing acidification of the urine, may increase the risk of kidney failure in myeloma patients. Incidentally, even Pauling and Cameron do not recommend their vitamin C treatment for multiple myeloma.

In general the attempt to "starve" the cancer by depriving the body of essential nutrients seems to be a difficult procedure, though the occasional anecdotes of impressive remissions for people on macrobiotic diets and similar regimens indicate that success is possible.

*--->This general approach might be made much more effective if preliminary tests were used to profile the nutritional vulnerabilities of the cancer. It would be expensive and difficult, as the cancer cells from each patient would have to be cultured in vitro and tested.

Most patients are more attracted to the idea of boosting nutrition. Physicians also prefer this, as cachexia (or "wasting disease") is commonly associated with cancer and can be a leading cause of death. Furthermore, nausea due to chemotherapy also interferes with nutrition.

Nutritional approaches can be divided into general nutrition, and specific nutrient effects. The objectives of a general nutrition program are as follows:

* General improvement of the physical reserves of the patient. The stronger the patient, the better the chance of survival--and the more chemotherapy that can be administered.

* Protection and stimulation of the immune system. Even if the immune system is inadequate to produce an antitumor effect, any increased protection against infection remains a valuable contribution, especially in multiple myeloma.

* Protection against the side-effects of chemotherapy (as discussed above).

Certain nutrient compounds may play specific roles in cancer treatment. In addition to the nutritional therapy applications mentioned elsewhere in this document, the following possibilities are of interest.

Coenzyme Q-10 seems to act as a non-specific stimulant of the immune system. A non-linear dose-response curve is obtained, which suggests that there are two effects, one activated with low doses, a second turning on at higher doses. [Bliznakov 1978]

Omega-3 polyunsaturated fatty acids suppress IL-1 (both alpha and beta) and tumor-necrosis factor (TNF). However, very high doses are required, about 18 grams/day. [Endres 1989; see also Dinarello 1993] Note that IL-1 promotes growth of myelogenous leukemia cells; on the other hand, it protects stem cells from radiation. [Epstein 1993] In vitro, omega-3 PFAs suppress the growth of leukemic T-cells. [Chow 1989] In vivo, fish oil is effective against pancreatic cancer in rats. It has been suggested [Stillwell 1993] that the anti-cancer effect of omega-3 fatty acids is due to an increase in cell membrane permeability.

Methionine in combination with choline prolonged survival of leukemic mice. [Anon 1991] On the other hand, it has been claimed that cancer cells in general are more dependent on methionine than are normal cells.

Vitamin E supplementation is said to inhibit production of IL-6. [Cannon 1991]

Vitamin D is said to inhibit growth of myeloma.

The use of carotenoids, particularly beta-carotene, in cancer treatment has been reviewed. [Bollag 1992; Tallman 1992] A single case study claims reversal of "pre-leukemia" using a cocktail of antioxidants (especially beta-carotene, 50 mg/day) and other vitamins [Braverman 1991]. Another case study found beta-carotene (300 mg/day) effective against CLL accompanied by cutaneous T-cell lymphoma [Baranowitz 1994]. General immunostimulant effects have been found for beta-carotene [Watson 1991].

It should be noted that beta-carotene is very non-toxic [Bendich 1988]. Another important point is that beta-carotene is absorbed very poorly from foods; thus consumption of 600 grams (!) of broccoli resulted in no measurable rise in serum beta-carotene. [Mathews-Roth 1991 and cited refs]

Herbal medicine so far has contributed little to myeloma treatment. One patent describes the use of extracts from Stephania tetranda to inhibit IL-6 production [Pyun 1995]. The antioxidant spice component curcumin promotes apoptosis in leukemia cell lines by downregulating bcl-2 [Kuo 1996]. Curcumin is a major component of turmeric and makes up 26% by weight of curry powder.

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VIth Internat. Myeloma Workshop 1997

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VIth Internat. Myeloma Workshop 1997.

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VIth Internat. Myeloma Workshop 1997

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Novel Oncogenes in Myeloma

VIth Internat. Myeloma Workshop 1997

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VIth Internat. Myeloma Workshop 1997

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Eight acute phase proteins were assayed in patients with MM (n = 51), MGUS (n = 17), and Waldenstrom's macroglobulinemia (n = 5). The CRP level was above 10 mg/l in 27% of all myeloma patients, in 39% of patients with active myeloma, in 4 of 5 patients with Waldenstrom's, and in none of the MGUS patients. Fibrinogen, alpha-1-antitrypsin, and orosomucoid levels were significantly higher in the myeloma group than in the MGUS group. Differences were not significant for haptoglobin, ceruleoplasmin, transferrin, and alpha-2-macroglobulin. Serial assays in 22 myeloma patients showed that CRP levels were correlated with disease activity. A biologic inflammatory syndrome, defined as a significant variation in two or more acute phase reactants, was demonstrated in 41% of myeloma patients, 18% of MGUS patients, and 60% of Waldenstrom's patients. Active disease was significantly more common among myeloma patients with biologic evidence of inflammation. These data suggest that acute phase reactants are markers for disease activity in MM.

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Interleukin-6 in Myeloma: Fact and Fiction.

Vth International Workshop on Multiple Myeloma, 1995.

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Phenotypic Characterization and Quantitation of Circulating Myeloma Cells.

VIth Internat. Myeloma Workshop 1997

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VIth Internat. Myeloma Workshop 1997

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Blood 83 (Nov), Abstract 3607 (1996).

Iwato-K. Kawano-M-M.

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[Myeloma precursor cells].

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LG Japanese (JA).

Heterogenous biological character of myeloma cells was associated with different expression of adhesion molecules. Myeloma cells could be phenotypically divided into two subpopulations: CD38++/VLA5+/MPC-1+(VLA-5+) cells and CD38++/VLA5-/MPC-1-(VLA-5-) cells. VLA-5- myeloma cells were morphologically immature and proliferated markedly with response to IL-6 in vitro, while VLA-5+ cells showed very low uptakes of 3H-TdR but secreted higher amounts of M-protein in vitro. These results suggest VLA-5- cells are proliferative precursor in myeloma. With respect to VLA-5 and MPC-1 expression, myeloma precursor cells (CD38++/VLA-5-/MPC-1-/CD10-/CD24-) showed similar phenotype to germinal center B cells (CD38+/VLA-5-/MPC-1-/CD10+/CD24-), rather than that of pre-B cells in the bone marrow (CD38+/VLA-5+/MPC-1-/CD10+/CD24+). Identification of precursor cells and characterization of their growth is important for the understanding of pathophysiology of myeloma and the therapeutic strategy. Author-abstract.

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Autologous Bone Marrow Transplantation in Multiple Myeloma: Identification of Prognostic Factors.

Blood 76, 1860 (1990).

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Autologous Bone Marrow Transplantation for Multiple Myeloma.

Hematol. Oncol. Clin. North Am. April 1992, 6, 437.

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Pretreatment with 1,25(OH)2D3 Protects from Cytoxan-Induced Alopecia without Protecting the Leukemic Cells from Cytoxan

Am. J. Med. Sci. 310, 43 (1995)

Joshua D. E., Snowdon L., Gibson J., et al

Multiple Myeloma: Plateau Phase Revisited.

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Multiple Myeloma: Why Does the Disease Escape from Plateau Phase?

Brit. J. Haem. 88, 667 (1994).

*Joshua DE. Brown RD. Gibson J. Iland H. Pope B. Springall F. (Royal Prince Alfred Hosp., Sydney)

Oncoproteins in Myeloma

VIth Internat. Workshop Multiple Myeloma 1997.

*Kawano M. et al.

Autocrine Generation and Requirement of BSF-2/IL-6 for Human Multiple Myelomas.

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Altered Expression of CD19 Gene May Be Related to Malignant Transformation of Plasma Cells.

Vth International Workshop on Multiple Myeloma, 1995.

*Kay NE. et al

Circulating CD19+ Blood Cell Levels in Myeloma.

Pilarski LM.

Response

Blood 84, 4000 (1995)

Kettle-P. Ranaghan-L. Markey-G-M. Robertson-J-H. Desai-Z-R. Bharucha-C. Morris-T-C.

Haematology Department, Belfast City Hospital.

Myeloma--results of treatment 1986-1990.

Ulster-Med-J. 1993 62(1). P 11-20.

Sixty-nine patients with multiple myeloma diagnosed during a five year period at the Belfast City Hospital were followed until death or for a minimum of one year in a retrospective study of survival. Although the patients were unselected, survival data was found to be similar to results from trials in which patient selection had occurred. Overall median survival was thirty-two months. Median survival fell with advancing disease and was 47, 27 and 18 months for Durie-Salmon stages I, II and III respectively. Those patients presenting with a platelet count of < 100 x 10(9)/1 had a median survival of eight months in contrast to those with a platelet count > 100 x 10(9)/1 whose median survival was 36 months. Patients presenting in renal failure had a shorter median survival of 28 months compared to 46 months for those with normal renal function.

Klein B. Zhang XG. Jourdan M. Boiron JM. Portier M. Lu ZY. Wijdenes J. Brochier J. Bataille R. (INSERM U291, Montpellier, France.)

Interleukin-6 Is the Central Tumor Growth Factor in vitro and in vivo in Multiple Myeloma.

Eur. Cytokine Netw. 1 (4), 1990 Oct.-Nov.

When bone-marrow cells from patients with multiple myeloma were seeded in short-term cultures, a spontaneous proliferation of the MM cells occurred for most of the patients with active disease and proliferating cells in vivo. In all cases, this spontaneous proliferation was inhibited by anti-IL-6 monoclonal antibodies. Moreover, myeloma cell lines, completely dependent upon exogenous IL-6 for their growth, could be reproducibly established by initiially stimulating the myeloma cells with both IL-6 and GM-CSF. These results demonstrate that IL-6 is a major paracrine myeloma-cell growth factor in vitro. High serum IL-6 levels were found in bone-marrow cells of MM patients, mainly in myeloid and monocytic cells, in vivo. The myeloma cells did not express IL-6 mRNA. Injection of anti-IL-6 moabs to MM patients with terminal disease and extramedullary proliferation completely blocked the myeloma cell proliferation in vivo and completely inhibited the serum IL-6 bioactivity and the serum CRP levels. One patient with plasma cell leukemia and hypercalcemia was treated for two months with anti-IL-6 moabs and maintained in remission for 2 months without major side effects. Interestingly, the serum calcium levels also decreased in these patients. All these results show that IL-6 is the main cytokine responsible not only for the myeloma-cell proliferation in vivo, but presumably also for the bone resorbtion processes observed in human MM.

*Klein B. Bataille R. (Lab. of Immuno-hematologic Oncology, Hotel-Dieu, Nantes, France.)

Cytokine Network in Human Multiple Myeloma.

Hematol. Oncol. Clin. North Am. April 1992, 6, 273.

*Klein B. et al.

Murine Anti-IL-6 Monoclonal Antibody Therapy for a Patient with Plasma Cell Leukemia.

Blood 78(5), 1198 (1991).

*Klein B. Zhang XG. Lu ZY. Bataille R.

Interleuking-6 in Human Multiple Myeloma.

Blood 85(4), 863 (1995).

*Knight GD. Laubscher KH. Fore ML. Clark DA. Scallen TJ. (Univ. New Mexico.)

Vitalethine Modulates Erythropoiesis and Neoplasia.

Cancer Res. 54, 5623 (1994).

*Knight GD. Mann PL. Laubscher KH. Scallen TJ. (Univ. New Mexico.)

Seemingly Diverse Activities of Beta-Alethine.

Cancer Res. 54, 5636 (1994).

*Kornbluth J. (Univ. Arkansas)

Modulation of Myeloma Susceptibility to Cell-Mediated Cytolysis by Cytokines.

Vth International Workshop on Multiple Myeloma, 1995.

Kraj M. Rostkowska J. Sokolowska U. Maj S. (Kliniki Hematologiczne Instytutu Hematologii, Warsaw.)

Clinical and Laboratory Analytis of the case of multiple myeloma with over 5-year survival time.

Acta Haematol. Pol. 22, 42 (1991)

Out of 436 studied patients with plasmocytic myeloma 67 (15.0%) survived over 5 years from the beginning of antineoplastic treatment, and 18 survived over 10 years from the first symptoms. The patients with long survival were younger at the time of diagnosis and had normal creatinine and calcium levels.

Kraut-E-H. Crowley-J-J. Grever-M-R. Keppen-M-D. Bonnet-J-D. Hynes-H-E. Salmon-S-E. (Ohio State University.)

PHASE II STUDY OF FLUDARABINE PHOSPHATE IN MULTIPLE MYELOMA. A SOUTHWEST ONCOLOGY GROUP STUDY.

Invest-New-Drugs. 1990 8(2). P 599-200.

Thirty-one patients with multiple myeloma refractory to therapy or relapsing after response to initial therapy were treated with Fludarabine Phosphate utilizing a daily intravenous schedule for five consecutive days. There were no objective responses seen and only one patient showed clinical improvement. Myelosuppression manifest as leucopenia and granulocytopenia was the primary toxicity seen. Fludarabine Phosphate is inactive in previously treated myeloma patients when given by the daily intravenous route.

Kumar R. Pelletier D. (Memorial Sloan-Kettering Cancer Center, New York, NY 10021.)

Augmentation of Interferon-Mediated Growth-Inhibitory and Gene-Inducing Responses of Human Hematopoietic Tumor Cell Lines by Retinoic Acid. (Meeting Abstract.)

Proc. Annu. Meet. Am. Assoc. Cancer Res. 33, A441 (1992).

Kuo ML. Huang TS. Lin JK. (Nati. Taiwan Univ.)

Curcumin, an Antioxidant and Antitumor Promoter, Induces Apoptosis in Human Leukemia Cells.

Biochim. Biophys. Acta 1317, 95 (1996).

*Kwak LW. Taub DD. Duffey PL. Bensinger WI. Bryant EM. Reynolds CW. Longo DI. (NCI; DynCorp; Hutchinson.)

Transfer of Myeloma Idiotype-Specific Immunity from an Actively Immunised Marrow Donor.

Lancet 345, 1016 (1995).

*Kyle RA. (Mayo Clinic.)

Why Better Prognostic Factors for Multiple Myeloma Are Needed.

Blood 83(7), 1713 (1994).

*Lehnert M, Dalton WS, Roe D, Emerson S, Salmon SE (Arizona Cancer Center)

Synergistic Inhibition by Verapamil and Quinine of P-Glycoprotein-Mediated Multidrug Resistance in a Human Myeloma Cell Line Model.

Blood 77, 348 (1991).

*Lust JA. Donovan KA. (Mayo Clinic)

Novel Therapeutic Strategies [for Myeloma]

VIth Internat. Myeloma Workshop 1997

MacLennan-I-C. Drayson-M. Dunn-J. (Department of Immunology, University of Birmingham Medical School.)

Multiple myeloma.

BMJ. 1994 Apr 16. 308(6935). P 1033-6.

Multiple myeloma occurs in over 2000 new patients in England and Wales each year. It presents most frequently as bone pain and patients tend to become dehydrated and may develop renal failure. No available treatment is curative, but about two thirds of patients achieve a stable response with low dose combination chemotherapy. Combination chemotherapy including doxorubicin and carmustine with the alkylating agents cyclophosphamide and melphalan achieve a higher stable response rate than conventional treatment with melphalan and prednisone without additional haematological toxicity. These responses are associated with loss of bone pain and patients remain symptom free for months without further treatment. Relapse occurs on average in a little under two years and, though second responses are frequently obtained, the disease eventually becomes refractory. This paper looks at who should be treated and the benefits that may be expected from the treatments available. Author-abstract. 47 Refs.

*Maclennan IC.

Origin of the Malignant Clone [in Myeloma]

VIth Internat. Myeloma Workshop 1997

*Maitland JA. Millar BC. Bell JBG. Montes A. Treleaven J. Gore ME. McElwain TJ. (Inst. Cancer Res. Royal Marsden Hospital, Sutton, Surrey, UK.)

Evidence that Multiple Myeloma May Be Regulated by Homeostatic Control Mechanisms: Correlation of Changes in the Number of Clonogenic Myeloma Cells in vitro with Clinical Response.

Br. J. Cancer 61, 429 (1990).

*Malpas JS. Bergsagel DE. Kyle RA.

Myeloma: Biology and Management.

Oxford University Press, 1995.

*Mandelli F. Avvisati G. Tribalto M. (Univ. La Sapienza, Rome.)

Biology and Treatment of Multiple Myeloma.

Curr. Opin. Oncol. 4(1), 73 (1992).

*Mansi J. da Costa F. VIner C. Judson I. Gore M. Conningham D. (Cancer Res. Campaign Section of Med., Royal Marsden Hospital, Sutton, Surrey, England.)

High-Dose Busulfan in Patients with Myeloma.

J. Clin. Oncol. 10(10), 1569 (1992).

Marmont F. Levis A. Falda M. Resegotti L. (Div. Hematol., Ospedale Milinette, Torino, Italy)

Lack of Correlation between Objective Response and Death Rate in Multiple Myeloma Patients Treated with Oral Melphalan and Prednisone.

Ann. Oncol. 2(3), 191 (1991).

*Massaia M., Attisano C., Paola S., Montacchini L., Omede P., Corradini P., Ferrero D., Boccadoro M., Bianchi A., Pileri A.

Rapid Generation of Antiplasma Cell Activity in the Bone Marrow of Myeloma Patients by CD3-Activated T-Cells.

Blood 82, 17871 (1993)

Treatment of MM cell lines with anti-CD3 monoclonal antibodies results in strong T-cell proliferation and rise in IL-2. A decrease in malignant plasma cells results.

*Massaia M. Borrione P. Attisano C. Barral P. Beggiato E. Montacchini L. Bianchi A. Boccadero M. Pileri A. (Univ. Turin.)

Dysregulated Fas and Bcl-2 Expression Leading to Enhanced Apoptosis in T-Cells of Multiple Myeloma Patients.

Blood 85, 3679 (1995).

*Massaia M.

Idiotypic Reactive T-Cells.

VIth Internat. Myeloma Workshop 1997

*Mathews-Roth MM. (Harvard Med. School.)

Recent Progress in the Medical Applications of Carotenoids.

Pure Appl. Chem. 63(1), 147 (1991).

Merlini-G. Perfetti-V. Gobbi-P-G. Quaglini-S. Franciotta-D-M. Marinone-G. Ascari-E. (Istituto di Clinica Medica II, University of Pavia, Italy.)

Acute phase proteins and prognosis in multiple myeloma.

Br-J-Haematol. 1993 83(4). P 595-601.

Serum IL-6 levels have been shown to correlate with disease severity and prognosis in patients with plasma cell dyscrasias. Among its pleiotropic actions, IL-6 is also the major regulator of the acute phase response in humans. The possible impact on survival of the major serum acute phase proteins (s.APP) [C-reactive protein (s.CRP), alpha-1-antitrypsin (s.AAT), haptoglobin, acid alpha-1-glycoprotein and alpha-2-macroglobulin (used as control)] was assessed on a population of 103 consecutive, previously untreated myeloma patients. Univariate analysis showed that among the acute phase proteins only s.AAT (P = 0.015) and s.CRP (P = 0.027) were significantly correlated with survival. The multivariate Cox proportional hazard model applied to s.APP and other common parameters showed that s.beta-2-microglobulin (s.b2M), s.calcium, s.creatinine, BM plasma cell percentage, age and s.AAT correlated significantly with survival. Combining s.b2M and s.AAT allowed stratification of myeloma patients: those with low levels of s.b2M (< or = 3 mg/l) and of s.AAT (< or = 3 g/l) presented an excellent prognosis (median survival exceeding 10 years) while those presenting higher values of the two parameters presented a median survival of 2.5 years (P = 0.002). Author-abstract.

*Michaeli J. Rifkind RA. Marks PA. (Sloan-Kettering)

Differentiating Agents in Cancer Therapy

Cancer Chemotherapy and Biol. Response Modifiers Annual 13, 286 (1992)

*Michaeli J. Zhang X. Siegel D. (Sloan-Kettering)

The Differentiation-Inducing Agent Hexamethylene Bisacetamide (HMBA) Induces Programmed Cell Death (Apoptosis) and Down-Regulates BCL-2 Expression in Human Myeloma Cells.

Vth International Workshop on Multiple Myeloma, 1995.

*Miller H. Leong T. Khandskar J. Greipp P. Kyle R. Kram J.

Paclitaxel [Taxol] s the Initial Treatment of Multiple Myeloma.

Blood 84(November), Abstract 738.

*Mills E.

The Modifying Effect of Beta-Carotene on Radiation and Chemotherapy Induced Oral Mucosis.

Brit. J. Cancer 57, 416 (1988).

*Mueller M. Green JR. Fabbro D. (Ciba-Geigy)

THe Bisphosphonate Pamidronate Inhibits the Growth of a Murine Myeloma Cell Line in Syngeneic Mice.

Blood 83 (Nov), Abstract 2333 (1996)

Muggia FM. WIllson JK. Weiss RB. (Div. Onc., NY Univ. Med. Center, New York, NY 10016.)

Respiratory Complications during Cancer Therapy: Diagnosis and Management.

Monogr. Ser. Eur. Organ Res. Treat. Cancer 7, 171 (1981).

Pulmonary fibrosis is rare with alkylating agents, except for busulfan. Treatment of pulmonary damage includes withdrawal of the causative agent, glucocorticoid therapy. Tetracycline and quinacrine may be used to treat pleural effusions.

*Munshi NC. Ding LM. Kornbluth J. Natubler S. Saylors R. Iver R. Srivastava A. Hoover R. Barlogie B. (Univ. Arkansas and Indiana Univ.)

Gene Therapy Strategies for the Treatment of Multiple Myeloma.

Abstract: Am. Soc. Hematology, 36th Annual Meeting, Dec. 1994, #672.

In IgG MM, an autoregulatory circuit is operative: CD8+ T-cells expressing a low-affinity Fcy receptor III (CD16) are expanded, and soluble CD16 (sCD16) shed by these cells inhibits IgG production by myeloma cells with ensuing myeloma cell death. An inverse relationship between serum sCD16 and tumor stage is also noted. . .

*Nguyen MH. Treon SP. Broitman SA. (Boston Univ. School of Med. 02118.)

In Vitro Studies of Taxol for the Treatment of Multiple Myeloma.

Abstract: Am. Soc. Hematology, 36th Annual Meeting, Dec. 1994, #702.

Based on in vitro tests, taxol is indicated to be more active than MP or VAD.

*Niesvizky R. Siegel DS. Busquets X. Nichols G. Muindi J. Warrell RP. Michaeli J. (Sloan-Kettering.)

Hypercalcaemia and Increased Serum IL-6 Levels Induced by All-trans Retinoic Acid in Patients with Multiple Myeloma.

Brit. J. Haem. 89, 217 (1995).

*Oken MM. (Virginia Piper Cancer Inst., Abbot Northwestern Hospital, Minneapolis.)

Standard Treatment of Multiple Myeloma.

Mayo Clin. Proc. 69, 781 (1994)

*Omede P. Boccadero M. Gallone G. Frieri R. Battaglio S. Redoglia V. Pileri A. (Univ. Torino.)

Multiple Myeloma: Increased Circulating Lymphocytes Carrying Plasma Cell-Associated Antigens as an Indicator of Poor Survival.

Blood 76(7), 1375 (1990).

Ong F. van Nieuwkoop JA. de Groot-Swings GM. Hermans J. Harvey MS. Kluin PM. Kluin-Nelemans JC. (Comprehensive Cancer Centre West, Leiden, Netherlands.)

BCL-2 Protein Expression Is Not Related to Short Survival in Multiple Myeloma.

Leukemia 9, 1282 (1995).

Paccagnella A. Chiarion-Sileni V. Soesan M. Baggio G. Bolzonella S. De Besi P. Casara D. Frizzarin M. Salvagno L. Favaretto A. et al. (Med. Onc. Dept., Padova Gen. Hospital, Italy.)

Second and Third Responses to the Same Induction Regimen in Relapsing Patients with Multiple Myeloma.

Cancer 68(5), 975 (1991).

*Park CH. Kimler BF.

Growth Modulation of Human Leukemic, Preleukemic, and Myeloma Progenitor Cells by L-Ascorbic Acid.

Am. J. Clin. Nutr. 54(6 suppl), 1241S (1991).

*Pellat-Deceunynk C.

Human Myeloma Cell Lines as a Tool for Studying the Biology of Multiple Myeloma: A Reappraisal 18 Years After.

Blood 84, 4002 (1995)

*Park CH. Kimler BF. (Texas Tech Univ.)

Growth Modulation of Human Leukemic, Preleukemic, and Myeloma Progenitor Cells by L-Ascorbic Acid.

Am. J. Clin. Nutr. 54, 1241S (1991).

Partii P. Dunlap WP. Kennedy RS. Ordy JM. Lane NE. (Fred Hutchinson Cancer Res. Center, Seattle.)

Motor and Cognitive Testing of Bone Marrow Transplant Patients after Chemoradiotherapy.

Percept. Mot. Skills 68, 1227 (1989).

*Peest D. et al. (Med. Hochschule Hannover.)

Low-Dose Recombinant IL-2 Therapy in Advanced Multiple Myeloma.

Brit. J. Haem. 89, 328 (1995).

*Pilarski LM. Jensen GS. (Univ. Alberta.)

Monoclonal Circulating B Cells in Multiple Myeloma.

Hematol. Oncol. Clin. North Am. April 1992, 6, 297.

*Pilarski LM. Smith AM. Mant MJ. Belch AR. (Univ. Alberta)

The Malignant Lineage in Myeloma: Dissemination of Disease.

Vth International Workshop on Multiple Myeloma, 1995.

*Pilarski LM.

Phenotypic Characterization and Quantitation of Circulating Myeloma Cells.

VIth Internat. Myeloma Workshop 1997

*Potter M. (NCI, Bethesda, MD.)

Perspectives on the Origins of Multiple Myeloma and Plasmacytomas in Mice.

Hematol. Oncol. Clin. North Am. April 1992, 6, 211.

*Puthier D. Bataille R. Barrille S. Mellerin MP. Harousseau JL. Ponzio A. Robillard N. Amiot M. (Inst. Biol. Nantes)

A New Vitamin D3 Derivative Induces Growth Arrest, Apoptosis and IL-6 Receptor Modulation on Myeloma Cells.

Blood 83 (Nov), Abstract 2337 (1996).

*Pyun KH. Choi I. Kang HS. Lee JJ. Kim YH. (Korea Inst. Science and Technology.)

Extracts of Stephania tetranda for Inhibition of Interleukin-6 Production.

PCT Int. Appl. 95 33,473 (12/14/95).

*Rettig MB. (UCLA)

The Role of Kaposi's Sarcoma-Associated Herpes Virus (KSHV) in Multiple Myeloma

VIth Internat. Workshop Multiple Myeloma 1997.

*Rettig MB. Ma HL. Vescio RA. Poeld M. Schiller G.; Belson D. Savage A. Nishikubo C. Wu C. Fraser J. Said JW. Berenson JR. (UCLA).

Kaposi's Sarcome-Associated Herpesvirus Infection of Bone Marrow Dendritic Cells from Multiple Myeloma Patients.

Science 276, 1851 (1997).

*Rettig MB. Said JW. Sun R. Vescio RA. Berenson J. (and other groups).

KSHV Infection and Multiple Myeloma. (Technical Comments)

Science 278, 1969 (1997a)

Sakalova-A. Mikulecky-M. Dedik-L. Prummerova-M. Gazova-S. Chabronova-I. Mistrik-M. Lipsic-T. (Subkatedra hematologie a transfuziologie FN LFUK, Bratislava.)

[Long-term survival in multiple myeloma].

Dlhodobe prezitie pri mnohopocetnom myelome.

Vnitr-Lek. 1994 Feb. 40(2). P 98-103.

JT VNITRNI LEKARSTVI.

Slovak (SL).

The authors present the results of 23-year protocol studies of survival with multiple myeloma, focused on problems of prospective long-term survival. Of 535 diagnosed patients between 1970 and 1990 the authors checked regularly and treated 475. In addition to 60 latent forms where treatment was administered only when clinical symptoms developed or after progression of laboratory signs, to all patients treatment was administered according to protocols (monotherapy-cyclophosphamide prednisone in 1970-1975 only to 30 patients, the remainder had combined treatment--COPP, VMCP, MOCCA); in the third stage of the disease MOCCA treatment is better. The median of survival of patients after VMCP treatment (in stage II) MOCCA (in stage III) is more than 90 months, 15% survive for more than 10 years. The authors emphasize the importance of combined intensive treatment of patients for the prognosis of survival. Long-term experience revealed that patients achieve an objective response in 85%, while the risk of leukaemic and cancerogenic complications is low (1.1%). The therapeutic effect and survival period are favourably affected by immunomodulation treatment (Interferon, proteolytic enzymes, thymus factor).

*Salmon SE. Dalton WS. Grogan TM. Plezia P. Lehnert M. Roe DJ. Miller TP. (Arizona Cancer Center)

Multidrug-Resistant Myeloma: Laboratory and Clinical Effects of Verapamil as a Chemosensitizer.

Blood 78, 44 (1991)

22 patients with refractory disease were treated with VAD + verapamil. 5 showed some response.

*Salmon SE. (Arizona Cancer Center)

New Therapeutic Approaches: Chemotherapy [of Myeloma]

Vth International Workshop on Multiple Myeloma, 1995

*Salmon SE. (Arizona Cancer Center)

New Therapeutic Approaches: Chemotherapy [of Myeloma]

VIth International Workshop on Multiple Myeloma 1997

*Sangfelt O. Oesterborg A. Grander D. Anderbring E. Oest A. Mellstedt H. Einhorn S. (Karolinska Hosp. & Inst.)

Response to Interferon Therapy in Patients with Multiple Myeloma Correlates with Expression of the BCL-2 Oncoprotein.

Int. J. Cancer 63, 190 (1995).

*Savage AD. Belson DJ. Vescio RA. Lichtenstein AK. Berenson JR. (UCLA)

Pamidronate Reduces IL-6 Production by Bone Marrow Stroma from Multiple Myeloma Patients.

Blood 83 (Nov), Abstract 409 (1996).

Shalet SM. (Dept. Endocrinology, Christie Hosp. and Holt Radium Inst., Manchester, England.)

Effects of Cancer Chemotherapy on Gonadal Function of Patients.

Cancer Treat. Rev. 7(3), 141 (1980).

*Shimizu K. Kamiya O. Takeyama H. Mizuno H. Kawashima K. (Nagoya Myeloma Cooperative Study Group).

Importance of Posttreatment Nadir M-Protein Level in the Evaluation of Treatment for Multiple Myeloma.

Blood supplement November 1997, abstract 4112.

*Sidell N. Taga T. Hirano T. Kishimoto T. Saxon A. (Dept. of Pathology, UCLA School of Medicine 90024.)

Retinoic Acid-Induced Growth Inhibition of a Human Myeloma Cell Line via Down-Regulation of IL-6 Receptors.

J. Immunol. 146(11), 3809 (1991).

*Siemasko K. Jack HM. Bremer E. Chong A. Williams J. Finnegan A. (Depts. Immunol. & Surgery, Rush Univ., Loyola Univ.)

The Immunosuppressive Agent, Leflunomide, Inhibits Immunoglobulin Production by Two Independent Mechanisms.

FASEB Abstracts 1996 (New Orleans, June 2-6), A1199.

Smith MA. Parkinson DR. Cheson BD. Friedman MA. (Pediatric Section, NCI, Bethesda, MD 20892.)

Retinoids in Cancer Therapy.

J. Clin. Oncol. 10(5), 839 (1992).

Sonneveld P. Durie BG. Lokhorst HM. Marie JP. Solbu G. Suciu S. Zittoun R. Lowenberg B. Nooter K. (Dept. Haematology, Erasmus Univ., Univ. Hosp. Dijkzigt, Rotterdam, Netherlands.)

Modulation of Multidrug-Resistant Multiple Myeloma by Cyclosporin.

Lancet 340, 255 (1992).

*Sonneveld P. (Dept. Haematology, Erasmus Univ., Univ. Hosp. Dijkzigt, Rotterdam, Netherlands.)

Modulation of Refractory Multiple Myeloma by MDR-Modulating Agents: Therapeutic Consequences.

Vth International Workshop on Multiple Myeloma, 1995

*Sonneveld P. (Dept. Haematology, Erasmus Univ., Univ. Hosp. Dijkzigt, Rotterdam, Netherlands.)

Reversing Drug Resistance in Myeloma.

VIth International Workshop on Multiple Myeloma 1997

*Stillwell W. Ehringer W. Jenski LJ. (Indiana Univ.)

Docosahexaenoic Acid Increases Permeability of Lipid Vesicles and Tumor Cells.

Lipids 28, 103 (1993).

*Suzuki H. Yasukawa K. Saito T. Goitsuka R. Hasegawa A. Ohsugi Y. Taga T. Kishimoto T.

Anti-Human IL-6 Receptor Antibody Inhibits Human Myeloma Growth in vivo.

Eur. J. Immunol. 22, 1989 (1992).

*Tallman MS. Wiernik PH. (Div. Hematology-Oncology, Northwestern Univ. Med. School, Chicago, IL 60611.)

Retinoids in Cancer Treatment.

J. Clin. Pharmacol. 32(10), 868 (1992).

Togawa-A. (Division of Internal Medicine, National Medical Center.)

[Recent therapy for refractory myeloma].

Rinsho-Ketsueki. 1993 34(4). P 450-4.

LG Japanese (JA).

There are only 3.3% of patients with multiple myeloma in Japan Myeloma Study Group who have lived longer than ten years. Features associated with long survival include responded well to simple treatment such as melphalan or cyclophosphamide and prednisone, short duration of treated time with long activity and prolonged unmaintained remissions. High-dose melphalan therapy, VAD chemotherapy and MCNU-VP16-melphalan combination were tried for patients relapsed with alkylating agents and the result were reported. Bone marrow transplantation and cytokine therapy for myeloma will be discussed. Author-abstract.

*Trebukhina R. Lashak L. Petushok V. Ledneva I. (Inst. Biochem. Acad. Sci., 230017, Grodno, Lenin Komsomol Blv. 50, Belarus.)

Antitoxic Effect of Thiamine in Experimental Oncology.

Meeting Abstract, in unidentified journal; 1996 (?), p. 74.

*Tricot G. Barlogie B. Jagannath S. Bracy D. Mattox S. Vesole DH. Naucke S. Sawyer JR. (Univ. Arkansas)

Poor Prognosis in Multiple Myeloma Is Associated Only with Partial or Complete Deletions of Chromosome 13 or Abnormalities Involving 11q and Not With Other Karyotype Abnormalities.

Blood 86, 4250 (1995)

Tu Y. Liu J. Vescio R. Berenson J. Fady C. Lichtenstein A.

Upregulated Expresssion of BCL-2 in Multiple Myeloma Cells Induced by Exposure to Doxorubicin, Etoposide, and Hydrogen Peroxide.

Blood 88, 1805 (1996).

*Tura S. Cavo M. (Univ. Bolagna.)

Allogeneic Bone Marrow Transplantation in Multiple Myeloma.

Hematol. Oncol. Clin. North Am. April 1992, 6, 425.

*Turley EA. Belch AJ. Poppema S. Pilarski LM. (Univ. Manitoba and Univ. Alberta.)

Expression and Function of a Receptor for Hyaluronan-Mediated Motility on Normal and Malignant B-Lymphoctyes.

Blood 81(2), 446 (1993).

*Umlauf S. W. Ryan U. S. (T Cell Sciences, 115 Fourth Ave., Needham, MA 02194-2725; 73400.1566@compuserve.com)

Immune System Under Assault in Massachusetts.

Nature Biotechnology 14, 830 (1996).

*Urashima, M. Ogata, A. Chauhan, D. Virales M. B. Teoh, G. Hoshi, Y. Schlossman, R. L. DeCaprio, J. A. Anderson, K. C. (Dana-Farber & Jikei Univ. School of Med. Tokyo).

Interleukin-6 Promotes Multiple Myeloma Cell Growth via Phosphorylation of Retinoblastoma Protein.

Blood 88(6), 2219 (1996).

*Van Camp B. Bakkus M. Vanderkerken K.; De Greet C.; Van Riet I. (Free Univ. Brussels)

Characterization of the Myeloma Clone

VIth Internat. Workshop Multiple Myeloma 1997.

*Van Ness B. (Inst. Human Genetics, Univ. Minnesota)

Clonally Related Cells in the Peripheral Blood of Myeloma Patients after Stem Cell Transplant.

VIth Internat. Workshop Multiple Myeloma 1997.

*Varterasian ML. (Wayne State Univ.)

Biologic and Clinical Advances in Multiple Myeloma.

Oncology 1995, 417.

*Watson RR. Prabhala RH. Plezia PM. Alberts DS. (Univ. Arizona.)

Effect of Beta-Carotene on Lymphocyte Subpopulations in Elderly Humans: Evidence for a Dose-Response Relationship.

Am. J. Clin. Nutr. 53, 90 (1991).

*Waxman J. (Dept. Med. Oncology, St. Bartholomew's Hosp., London EC1A 7BE.)

Chemotherapy and the Adult Gonad: A Review.

J. R. Soc. Med. 76(2), 144 (1983).

After cytotoxic chemotherapy, testosterone and luteinizing hormone levels are normal in men, although destruction of germ cells causes follicle-stimulating hormone (FSH) levels to increase and prolactin may also be elevated. Generally, alkylating agents are more toxic to the gonads than antimetabolites. Mustine is probably most toxic to the gonad. Clinical trials are under way to investigate use of superactive analogs of GRH for gonadal protection during therapy.

*Weber, M. ..... Alexanian R. (M. D. Anderson).

Induction of Autologous GVHD in Patients with Multiple Myeloma Undergoing High-Dose Chemothorapy with ASCR.

VIth Internat. Myeloma Workshop 1997

*Westin J. Rodjer S. Turesson I. Cortelezzi A. Hiorth M. Zador G. (Univ. Hospital, Lund, Sweden.)

Interferon alfa-2b versus No Maintenance Therapy During the Plateau Phase in Multiple Myeloma: A Randomized Study.

Brit. J. Haematol. 89, 561 (1995).

*Winearls CG. (Churchill Hospital, Oxford, England).

Acute Myeloma Kidney.

Kidney International 48, 1347 (1995).

Wood L.

Possible Prevention of Adriamicin-Induced Alopecia by Tocopherol.

New Eng. J. Med. 312, 1060 (1985).

Yamagishi Y. Hidaka Y. Sasaki K. Hihei K. Itoh Y. Kawai T.

Determination of Serum IL-6 Concentration by an Enzyme-Linked Immunosorbent Assay in Patients with Paraproteinemia.

Rinsho Byori 40(3), 303 (1992).

An enzyme-linked immunosorbent assay of human IL-6 was developed by Fujirebio Inc. Its sensitivity was 3 pg/ml and its analytical range was from 3 to 200 pg/ml. The serum IL-6 levels in 200 normal individuals were less than 3 pg/ml. Serum IL-6 concentration in patients with malignant and benign monoclonal gammopathy (BMG) was determined by an ELISA. Serum IL-6 concentration in patients with Bence Jones protein (BJP) type MM (n = 12) was 12.3 +/- 12.7 [mean +/- sd]. The correlation between serum IL-6 and C-reactive protein (CRP) was r = 0.563 in MM patients (n = 61) and r = 0.498 in patients with BMG (n = 43).

Yeager AM. Vogelsang GB. Jones RJ. Farmer ER. Altomonte V. Hess AD. Santos GW.

Induction of Cutaneous Graft-vs-Host Disease by Administration of Cyclosporine to Patients Undergoing Autologous Bone Marrow Transplantation for Acute Myeloid Leukemia.

Blood 79(11), 3031 (1992).

*Zhang X. Siegel D. Niesvizky R. Zelenetz A. Michaeli J. (Memorial Sloan-Kettering Cancer Center, Div. Haem.-Onc.)

Hexamethylene Bisacetamide (HMBA) Induces Programmed Cell Death (Apoptosis) and Down Regulates bcl-2 Expression in Human Myeloma Cells.

Abstract: Am. Soc. Hematology, 36th Annual Meeting, Dec. 1994, #687.