Multiple myeloma

Efficacy and safety results with the combination therapy of arsenic trioxide, dexamethasone, and ascorbic acid in multiple myeloma patients: a phase 2 trial

BACKGROUND

Single-agent arsenic trioxide has shown promising results in patients with relapsed or refractory multiple myeloma (MM). Because preclinical data suggested greater activity with dexamethasone and ascorbic acid, a phase 2 trial of the combination of arsenic trioxide, dexamethasone, and ascorbic acid in patients with relapsed or refractory MM was conducted.

METHODS

Twenty patients in whom no more than two previous therapies had failed were enrolled. The mean age was 62 yr, and 55% of the patients had refractory disease. The regimen consisted of 14- or 15-wk cycles, with the first cycle considered induction, followed by one or two consolidation cycles with a reduced steroid schedule and then a maintenance cycle in responding patients.

RESULTS

The overall response rate was 30%, with at least stable disease in 80% of patients. Median progression- free survival was 316 d in all patients and 584 d in those with a response. The regimen was well tolerated, with most adverse events being mild or moderate.

CONCLUSIONS

This study showed the clinical efficacy and tolerability of the combination of arsenic trioxide, dexamethasone, and ascorbic acid. Further study is warranted.

Advances in oral therapy in the treatment of multiple myeloma

Conventional IV chemotherapy regimens used for induction chemotherapy or salvage therapy in the treatment of multiple myeloma (MM) are cumbersome, with a negative impact on patient quality of life. A number of new oral drugs, including immunomodulatory agents such as thalidomide and lenalidomide, have demonstrated potent antimyeloma activity in relapsed and refractory as well as newly diagnosed MM. Clinically, response rates of 56%-72% have been reported with the combination of thalidomide and dexamethasone in patients with newly diagnosed disease; however, the combination is associated with a higher incidence of side effects, including constipation, somnolence, peripheral neuropathy, and thromboembolic complications. In contrast, preliminary safety and efficacy data from clinical studies of lenalidomide show promise. Response rates as high as 83% have been reported in patients with newly diagnosed MM, and the most common adverse event is manageable myelosuppression, which is reversible with dose reduction. Lenalidomide has different toxicities than thalidomide, exhibiting greater myelosuppression but virtually no constipation, somnolence, or peripheral neuropathy. Oncology nurses play a key role in monitoring patients for side effects and pain control and educating them about emerging treatment options. This article reviews the nursing experience with oral agents in the treatment of MM.

Cancer-testis antigens are commonly expressed in multiple myeloma and induce systemic immunity following allogeneic stem cell transplantation

Immunotherapies using cancer-testis (CT) antigens as targets represent a potentially useful treatment in patients with multiple myeloma (MM) who commonly show recurrent disease following chemotherapy. We analyzed the expression of 11 CT antigens in bone marrow samples from patients with MM (n=55) and healthy donors (n=32) using reverse transcriptase-polymerase chain reaction (RT-PCR). CT antigens were frequently expressed in MM with 56% (MAGEC2), 55% (MAGEA3), 35% (SSX1), 20% (SSX4, SSX5), 16% (SSX2), 15% (BAGE), 7% (NY-ESO-1), and 6% (ADAM2, LIPI) expressing the given antigen. Importantly, CT antigens were not expressed in healthy bone marrow. Analyzing patients with MM (n=66) for antibody responses against MAGEA3, SSX2, and NY-ESO-1, we found strong antibody responses against CT antigens preferentially in patients who had received allogeneic stem cell transplantation (alloSCT). Antibody responses against NY-ESO-1 correlated with NY-ESO-1-specific CD4+ and CD8+ T-cell responses against peptide NY-ESO-1(51-62) and CD4+ responses against NY-ESO-1(121-140) in 1 of these patients. These allogeneic immune responses were not detectable in pretransplantation samples and in the patients' stem cell donors, indicating that CT antigens might indeed represent natural targets for graft-versus-myeloma effects. Immune responses induced by alloSCT could be boosted by active CT antigen-specific immunotherapy, which might help to achieve long-lasting remissions in patients with MM.

Targeting PKC in multiple myeloma: in vitro and in vivo effects of the novel, orally available small-molecule inhibitor enzastaurin (LY317615.HCl)

In multiple myeloma (MM) protein kinase C (PKC) signaling pathways have been implicated in cell proliferation, survival, and migration. Here we investigated the novel, orally available PKC-inhibitor enzastaurin for its anti-MM activity. Enzastaurin specifically inhibits phorbol ester-induced activation of PKC isoforms, as well as phosphorylation of downstream signaling molecules MARCKS and PKCmu. Importantly, it also inhibits PKC activation triggered by growth factors and cytokines secreted by bone marrow stromal cells (BMSCs), costimulation with fibronectin, vascular endothelial growth factor (VEGF), or interleukin-6 (IL-6), as well as MM patient serum. Consequently, enzastaurin inhibits proliferation, survival, and migration of MM cell lines and MM cells isolated from multidrug-resistant patients and overcomes MM-cell growth triggered by binding to BMSCs and endothelial cells. Importantly, strong synergistic cytotoxicity is observed when enzastaurin is combined with bortezomib and moderate synergistic or additive effects when combined with melphalan or lenalidomide. Finally, tumor growth, survival, and angiogenesis are abrogated by enzastaurin in an in vivo xenograft model of human MM. Our results therefore demonstrate in vitro and in vivo efficacy of the orally available PKC inhibitor enzastaurin in MM and strongly support its clinical evaluation, alone or in combination therapies, to improve outcome in patients with MM.

Palifermin in a hematopoietic stem cell transplant patient with osteonecrosis of the jaw

This case report describes the use of palifermin in a multiple myeloma patient with a history of osteonecrosis of the jaw (ONJ) for the prevention of high-dose chemotherapy-induced mucositis. Following the day of autologous stem cell infusion, palifermin was discontinued secondary to adverse events. Specifically, palifermin-associated macroglossia seemed to exacerbate the pain localized in the oral cavity area affected by ONJ, necessitating escalated doses of narcotic analgesics. When contemplating palifermin as a mucosal protectant in a hematopoietic stem cell transplant patient with ONJ, a careful benefit-to-risk assessment is in order to ensure optimal effectiveness without undue harm.

Bortezomib increases osteoblast activity in myeloma patients irrespective of response to treatment

OBJECTIVES

Myeloma bone disease is a result of excessive osteoclast activation and impaired osteoblast function. Recent in vitro studies suggested that proteasome inhibitors might increase osteoblast function.

METHODS

We analyzed serum markers of osteoblast activity in 25 patients with multiple myeloma receiving bortezomib alone or in combination with dexamethasone. As control, serum samples from 58 consecutive myeloma patients receiving a therapy different than bortezomib (i.e. adriamycin/dexamethasone, melphalan/prednisone or thalidomide) were evaluated. The serum concentrations of bone-specific alkaline phosphatase (BAP) and osteocalcin were quantified before initiation of treatment and after 3 months.

RESULTS

In patients treated with bortezomib, mean serum levels of osteocalcin significantly increased from 6.3 to 10.8 microg/L (P = 0.024), while mean BAP levels increased from 19.7 to 30.2 U/L (P < 0.0005). Of interest, the increase in BAP was significant both in responders and non-responders. In contrast, the control group did not show a statistically significant change in BAP (24.8 U/L vs. 23.3 U/L) and osteocalcin (6.8 microg/L vs. 6.5 microg/L) before and after the treatment.

CONCLUSION

These data show that treatment with bortezomib leads to enhanced markers of osteoblast activity in patients with myeloma. The comparison with the control group suggests that the effect on osteoblasts is unique to the proteasome inhibitor.

Vincristine, doxorubicin, and dexamethasone or thalidomide plus dexamethasone for newly diagnosed patients with multiple myeloma?

Multiple myeloma (MM) is a malignant plasma cell tumor that is distributed at multiple sites within the bone marrow compartments. High-dose dexamethasone regimens [including vincristine, doxorubicin, and dexamethasone (VAD) chemotherapy] induce rapid responses, and have resulted in improved survival for many patients when followed by intensive therapy with autologous stem cell support early in the disease course. However, VAD have several disadvantages including the need for an intravenous indwelling catheter, which predisposes patients to catheter-related sepsis and thrombosis; most of the activity of VAD was from high-dose dexamethasone component. We enrolled all patients who fulfilled entire criteria for MM during the period between January 1997 and December 2005. The present study is a descriptive, retrospective, longitudinal, and observational one. The frequency of response (CR, VGPR/NCR, and PR) in the group of thalidomide and dexamethasone was 84.3% (CR 18.75% VGPR/NCR 18.75%, and PR 46.8%) being higher than VAD, 55% (CR 16%, VGPR/NCR 5%, and PR 34%). P = 0.0005. In summary, we conclude Thal/dex is an effective therapy in newly diagnosed MM inducing objective responses in over 84.3%.

Pleomorphic presentation of cutaneous lesions associated with the proteasome inhibitor bortezomib in patients with multiple myeloma

The clinical course and histologic findings of cutaneous adverse reactions associated with bortezomib treatment are presented in this study. Bortezomib (Velcade) is a proteasome inhibitor, which is used as a novel anticancer drug in the treatment of multiple myeloma. We have conducted an observational analysis of 47 patients with myeloma who were treated with bortezomib in 3 prospective clinical trials. Cutaneous adverse reactions were observed in 6 patients (13%). Five patients presented with sharply demarcated erythematous plaques or nodules on the trunk and one patient had generalized morbilliform erythema with ulcerations and fever. The time between the first bortezomib dose and occurrence of the cutaneous eruptions was at least 30 days. The cutaneous eruptions usually resolve within a few days. One patient withdrew from further treatment because of severe cutaneous toxicity. The histologic findings ranged from perivascular dermatitis to interstitial and interface dermatitis corresponding with clinically more extensive lesions.

Drug discovery in the ubiquitin-proteasome system

Regulated protein turnover via the ubiquitin-proteasome system (UPS) underlies a wide variety of signalling pathways, from cell-cycle control and transcription to development. Recent evidence that pharmacological inhibition of the proteasome can be efficacious in the treatment of human cancers has set the stage for attempts to selectively inhibit the activities of disease-specific components of the UPS. Here, we review recent advances linking UPS components with specific human diseases, most prominently cancer and neurodegenerative disorders, and emphasize potential sites of therapeutic intervention along the regulated protein-degradation pathway.

Multiple myeloma bone disease: Pathophysiology of osteoblast inhibition

Multiple myeloma (MM) is a plasma cell malignancy characterized by a high capacity to induce osteolytic bone lesions. Bone destruction in MM results from increased osteoclast formation and activity that occur in close proximity to myeloma cells. However, histomorphometric studies have demonstrated that MM patients with osteolytic bone lesions have lower numbers of osteoblasts and decreased bone formation. This impaired bone formation plays a critical role in the bone-destructive process. Recently, the biologic mechanisms involved in the osteoblast inhibition induced by MM cells have begun to be elucidated. In this article, the pathophysiology underlying osteoblast inhibition in MM is reviewed.

Extramedullary relapse of multiple myeloma presenting as hematemesis and melena

BACKGROUND

A 60-year-old woman with multiple myeloma relapsed after a good partial response to high-dose chemotherapy (melphalan 200 mg/m(2)) and autologous stem-cell transplantation, followed by thalidomide and prednisolone maintenance therapy. She presented with hematemesis and melena following salvage chemotherapy with dexamethasone, cyclophosphamide, etoposide, cisplatin, and rescue therapy with single-agent bortezomib.

INVESTIGATIONS

Physical examination, laboratory investigations, gastroscopy, 2-[(18)F]fluoro-2-deoxyglucose-PET (FDG-PET), breast biopsy and histology.

DIAGNOSIS

Multifocal extramedullary relapse of multiple myeloma involving the stomach and duodenum.

MANAGEMENT

High-dose infusion of omeprazole, blood product support, palliative analgesics and anxiolytic agents.

Cyclophosphamide mobilization does not improve outcome in patients receiving stem cell transplantation for multiple myeloma

PURPOSE

Patients with multiple myeloma who undergo autologous stem cell transplantation (ASCT) and exhibit a complete response (CR) have a superior overall survival and time to progression (TTP). High-dose cyclophosphamide is often used before ASCT for mobilization of hematopoietic stem cells. We hypothesized that cyclophosphamide might further improve CR rates in patients undergoing ASCT. We searched the Mayo Clinic myeloma transplantation database for patients who had stem cell mobilization with hematopoietic growth factor alone or cyclophosphamide and growth factor. The impact of cyclophosphamide on CR rates and TTP was evaluated.

PATIENTS AND METHODS

A cohort of 201 patients was identified: 127 mobilized with cyclophosphamide and growth factor and 74 with growth factor alone. There were no statistically significant differences between the 2 cohorts in regard to age, sex, b2-microglobulin level, plasma cell labeling index, cytogenetics, conditioning regimen, or disease status at time of transplantation.

RESULTS

Complete response rates were 37.4% and 41.3% (P = 0.6115) for patients mobilized with cyclophosphamide combined with growth factor and growth factor alone, respectively, and TTPs were 19.9 months and 20.9 months (P = 0.59). In a multivariate analysis for TTP, cytogenetics and CR rates were the only independent variables (P = 0.0012 and P < 0.0001, respectively).

CONCLUSION

We conclude that high-dose cyclophosphamide does not increase overall CR rates or improve TTP for patients with myeloma undergoing ASCT.

Epidemiology and outcomes research for MGUS, myeloma and amyloidosis

The epidemiology of plasma cell dyscrasias clearly links to a complicated multi-factorial pathogenic pathway that at the individual patient level gives no clear indication of why the malignant process has occurred but factors in the environment and within the genome give clues and are discussed. MGUS is a pre-malignant disorder characterised by monoclonal plasma cell proliferation in the bone marrow and no end-organ damage; the patients are asymptomatic. Primary amyloidosis is a rare disorder that is characterised by deposition of amyloid fibrils composed of immunoglobulin light chain fragments; symptoms relate to the affected organ. Multiple myeloma is a malignant disease of plasma cells and with improvements in treatment, patients can now expect a doubling of median survival to 5 years, a 20% chance of surviving >10 years and a 50% chance of complete remission (CR), morphological and biochemical. The challenge is now to determine exactly what this means to the individual myeloma patient in terms of benefit, and to society as a whole and this is the basis of 'outcomes research' which is discussed in this review.

Derivative (1;7)(q10;p10) in multiple myeloma. A sign of therapy-related hidden myelodysplastic syndrome

Therapy-related myelodysplastic syndrome (MDS) is a major problem in long-term cancer survivors, therefore early detection and prevention of therapy-related secondary neoplasia is an important issue. We searched for therapy-related MDS and analyzed cytogenetic changes in 155 patients with multiple myeloma (MM) from a single institution. Of the total 155 MM patients with cytogenetic results, 7 patients showed de novo appearance of myeloid-related cytogenetic changes, and 5/7 had -7/7q-, including 3 with der(1;7)(q10;p10): 3 patients developed MDS (i.e. 2 patients with der(1;7)(q10;p10) and 1 with a complex abnormality including -5 and 7q-). Among five patients receiving more than 2 g of melphalan, three developed MDS, and two of them showed der(1;7)(q10;p10) before or at the time of MDS diagnosis. Although morphologic identification of MDS was difficult in some cases, we concluded that the presence of 7q-, specifically der(1;7)(q10;p10), during chemotherapy involving melphalan for MM patients might indicate hidden MDS status and appropriate therapeutic options should be considered for such patients.

Biology and treatment of multiple myeloma

Multiple myeloma (MM) is a B cell malignancy that accounts for 10% of all hematologic cancers. In recent years much has been learned regarding the biology of the myeloma clone; specifically on the chromosomal alterations that can be more frequently found and on the involved oncogenes. It has been also demonstrated that, in MM, bone marrow microenvironment, both in its cellular (stromal cells, osteoblasts, osteoclasts, endothelia) and protein (extracellular matrix) components, plays an important role in promoting growth and survival of malignant plasma cells. Much of this knowledge will be translated into a better patients treatment; although high-dose therapy programs can be considered the treatment of choice for patients aged 70 or younger, novel drugs, targeting MM clone in its microenvironment can be incorporated into these therapeutic programs improving response rate and patients survival.

CD52 antigen expressed by malignant plasma cells can be targeted by alemtuzumab in vivo in NOD/SCID mice

OBJECTIVE

To explore new treatments specifically targeting malignant plasma cells (PCs), we examined CD52 antigen expression on primary PCs as well as multiple myeloma (MM) cell lines, and investigated in vivo the antimyeloma activity of alemtuzumab.

MATERIALS AND METHODS

PCs were enriched from the marrow of MM patients (n = 39) according to CD138 expression and then analyzed by 3-color flow cytometry and quantitative PCR. The in vivo activity of alemtuzumab was evaluated in a xenotransplant model of MM in nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice.

RESULTS

CD52 expression revealed a substantial heterogeneity in terms of both percentage of positive cells and fluorescence intensity, with 25/39 (64%) MM patients showing >or=30% CD138(+) PCs expressing the CD52 antigen (mean = 79%; range, 33-100%). Similarly to primary cells, cell lines showed heterogeneous CD52 expression. Expression of CD52 mRNA by quantitative PCR analysis strongly correlated with CD52 antigen detection by flow cytometry. In vivo, alemtuzumab treatment significantly increased the median survival of animals with an early- (64 vs 77 days, p <or= 0.0005) or advanced-stage (66 vs 75 days, p <or= 0.02) disease.

CONCLUSION

We conclude that: 1) CD52 is expressed on PCs of a significant proportion of MM patients; 2) alemtuzumab used as a single agent exerts a good antitumor activity in NOD/SCID mice bearing an early-stage disease; and 3) alemtuzumab might have therapeutic potential in a subset of MM patients.

State of the art therapy in multiple myeloma and future perspectives

Treatment for multiple myeloma (MM) has changed beyond recognition in the past decades. While until the early 1980s, MM caused a slow progressive decline in quality of life until death after about two years, today's patients can expect a 50% chance of achieving a complete remission, a median survival time of five years and a 20% chance of surviving longer than ten years. State of the art therapy comprises: evidence-based supportive care; highly effective and well tolerated chemotherapeutic regimens; and for patients qualifying for intensive high-dose conditioning, autologous haematopoietic stem cell transplantation (HSCT) is an option. Maintenance therapy has become increasingly important since a majority of patients is able to achieve a good remission after front-line therapy which is aimed to be preserved as long as possible. In addition, improved understanding of the disease biology has led to the development of novel biological treatment agents, such as thalidomide, bortezomib and others, targeted at cellular mechanisms and interactions, e.g. with the bone marrow microenvironment. These strategies are incrementally integrated into modern MM care. This review considers recent clinical advancements in anti-myeloma strategies and provides an overview of the state of the art management of MM patients.

hMLH1 and MGMT inactivation as a mechanism of tumorigenesis in monoclonal gammopathies

Monoclonal gammopathies are a group of disorders characterized by clonal proliferation and accumulation of immunoglobulin-producing plasma cells. Multiple myeloma and monoclonal gammopathy of undetermined significance are the most common monoclonal gammopathies; the two comprise a spectrum of disorders, ranging from a relatively benign disease, monoclonal gammopathy of undetermined significance, to a malignant disease, multiple myeloma. Aberrant promoter methylation represents a primary mechanism of gene silencing during tumorigenesis. DNA repair systems act to maintain genome integrity in the presence of replication errors, environmental insults, and the cumulative effects of aging. The methylation patterns of two genes implicated in DNA repair, O6 methylguanine DNA methyl-transferase (MGMT) and human mutL homologue1 (hMLH1) have been detected in various solid tumours. With the purpose of studying the gene silencing of MGMT and hMLH1 in plasma cell disorders, we investigated the methylation status and expression of both genes in: 29 cases of multiple myeloma; one case of plasma cell leukaemia; 13 cases of monoclonal gammopathy of undetermined significance; and two cases of polyclonal plasmacytosis, using methylation-specific polymerase-chain reaction and immunohistochemical techniques. Methylation frequencies for MGMT were 23% in multiple myeloma and 8% in monoclonal gammopathy of undetermined significance. It was 10% for hMLH1 in multiple myeloma. None of the patients diagnosed with monoclonal gammopathy of undetermined significance had hMLH1 hypermethylated. In addition, 50% of myeloma cases had a loss of hMLH1 expression, whereas silencing of MGMT was observed in 43% of myeloma and 36% of samples with monoclonal gammopathy of undetermined significance. This study indicates that repair pathway defects play a role in the pathogenesis and evolution of monoclonal gammopathies, and suggests that inactivation of hMLH1 could be implicated in multiple myeloma tumorigenesis.

In vivo and in vitro cytotoxicity of R-etodolac with dexamethasone in glucocorticoid-resistant multiple myeloma cells

Glucocorticoids have been widely used in the treatment of multiple myeloma (MM) both as single agents and in combination with other drugs. However, primary or acquired glucocorticoid resistance occurs in most cases. It was recently reported that R-etodolac induced in vitro cytotoxicity in MM cell lines and in primary MM cells, as well as synergistically enhanced dexamethasone (Dex)-induced apoptosis in Dex-sensitive MM.1S cells. This study examined the in vitro and in vivo effects of combination treatment with R-etodolac and Dex on Dex-resistant OPM1 cells. Treatment with R-etodolac and Dex was found to enhance cytotoxicity, inhibit nuclear factor kappaB activity via upregulation of IkappaBalpha, as well as enhance Dex-induced caspase activation and poly (ADP)-ribose polymerase cleavage in OPM1 cells. R-etodolac also enhanced Dex cytotoxicity in patient MM cells that were resistant to glucocorticoids. The in vivo anti-tumour effect of this combination on MM cells was evaluated by using severe combined immunodeficient mice engrafted with OPM1. Treatment with R-etodolac or Dex alone did not induce a significant reduction of tumour volume; in contrast, combination treatment with R-etodolac and Dex induced significant synergistic inhibition of tumour growth. These data indicate that R-etodolac overcomes resistance to Dex in glucocorticoid-resistant MM cells, providing the framework for clinical trials of R-etodolac combined with Dex, to improve patient outcome in MM.

Signalling and survival pathways in multiple myeloma

The main factors that govern the pathophysiology and malignant growth of multiple myeloma (MM) are genetic defects within the tumour and the interaction between myeloma cells and the bone marrow microenvironment (BMM). This interaction leads to the activation of signalling pathways that promote the expansion of the malignant clone and stimulate neoangiogenesis and osteoclastogenesis. For many years, the cytokine interleukin-6 (IL-6) was considered a central growth factor and was thus believed to play a pivitol role in the pathogenesis of MM. However, increasing numbers of cytokines, chemokines and cell-to-cell contacts provided by the BMM have since been found to support MM cells. It has consistently been demonstrated that oncogenic mutations as well as the BMM stimulate IL-6-independent signalling pathways that protect MM cells from apoptosis. Consequently, multiple targeting of a complex signalling network rather than inhibition of a single pathway or growth factor is required to effectively induce myeloma cell death. Because the tumour suppressor p53 is rarely mutated in MM, non-genotoxic activation of the p53-dependent death pathway could be another attractive therapeutic strategy for this disease. Even though a number of promising new drugs are currently being tested in MM, a comprehensive knowledge of the signalling and survival pathways should pinpoint additional molecular targets and lead to the development of novel and hopefully more effective treatment strategies.

Efficacy of up-front treatment with a double stem cell transplantation in multiple myeloma

BACKGROUND

We report the outcome of 53 patients with multiple myeloma (MM), who received autologous stem cell transplantation (ASCT) from April 1996 to September 2004 at our institution and who survived for more than 3 months after the transplant.

METHODS

Following the first ASCT, 36 patients underwent an up-front second SCT, which consisted of either an ASCT (n = 24) or a reduced-intensity conditioning allogeneic stem cell transplant (RIST) (n = 12). Seventeen patients were given maintenance treatment.

RESULTS

Seventy-seven percent of the patients (n = 41) showed an objective response to the initial therapy prior to the first ASCT. Overall, 60.4% (32 out of 53) and 32.1% (17 out of 53) of the patients had a complete response (CR) and partial response (PR) after the first ASCT, respectively. At the time of analysis, 34 patients (64.2%) were still alive. With a median follow-up of 32 months (range 9-98), the estimated progression-free survival (PFS) and overall survival (OS) at 5 years were 17.0 and 34.9%, respectively. Multivariate analysis revealed that the second SCT, normal hemoglobin and <50% marrow plasma cells were associated with an improved PFS. A second SCT, CR to the first SCT, female gender and an absence of advanced bone lesions were associated with a better OS.

CONCLUSIONS

A second SCT is the most significant factor for an improved PFS and OS after the first ASCT (P < 0.001, respectively). Up-front double SCT is needed to improve the OS and PFS in patients with MM.

Conventional diagnostics in multiple myeloma

This paper reviews the most relevant laboratory techniques currently used for the evaluation of patients with multiple myeloma (MM) and other monoclonal gammopathies. Although the bone marrow morphological examination and electrophoretic analysis of the monoclonal paraprotein still remain the 'gold standard' techniques for fast, accurate and cost-effective diagnosis, other assays such as immunophenotyping, DNA cell content and cell cycle analysis measured by flow cytometry may contribute to a better assessment of myeloma patients. Here, we will discuss not only the contribution of each technique to differential diagnosis of monoclonal gammopathies, but also the value of each parameter as prognostic factor and for monitoring treatment efficacy. In addition, possible technical pitfalls inherent to each technique will be analysed.

Thalidomide and lenalidomide in the treatment of multiple myeloma

Although multiple myeloma (MM) is incurable with currently available treatments, the introduction of thalidomide and the development of safer and more active thalidomide analogues represent a major advance in the therapy of this disease. Thalidomide, initially introduced for treatment of MM because of its anti-angiogenic properties, has shown remarkable activity alone and in combination with other drugs in patients across all stages of the disease. Given the potential for teratogenicity with thalidomide and the non-haematologic toxicities of the drug, several analogues referred to as "immunomodulatory drugs" (IMiDs) were developed with the intent of enhancing the immunomodulatory effect while minimizing the teratogenic risk. Lenalidomide (CC-5013) and Actimid (CC-4047) are the first such analogues to undergo clinical testing. Lenalidomide has shown impressive activity in relapsed refractory myeloma as well as newly diagnosed disease. The precise mechanism of anti-MM activity of thalidomide and the IMiDs is not clear, but studies suggest that several other mechanisms besides anti-angiogenic effects may play a role. In this paper we review the development, pharmacology, mechanism of action, pre-clinical and clinical efficacy, and the current status of thalidomide and the IMiDs in the treatment of MM.

Paraproteinemic neuropathies

Paraproteinemic neuropathies comprise a diverse group of disorders that includes monoclonal gammopathy of undetermined significance, primary amyloidosis, multiple myeloma, cryoglobulinemia, POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein and skin changes) syndrome, and Waldenstrom macroglobulinemia. Various factors including hepatitis C virus, vascular endothelial growth factor, and an array of cytokines are implicated in the pathogenesis of these conditions. More recently, a variety of novel antibody specificities, and vasculitis, have also been described as contributory factors in the development of these neuropathies. Therapeutic approaches for paraproteinemic neuropathies have included administration of cytotoxic agents, steroids, interferon-alpha, intravenous immunoglobulin, radiation, bone marrow transplantation, and more recently, drugs such as rituximab and bevacizumab. In this article, we review some of the well-known features of these diseases, and highlight some of the more recent findings from the vast literature for these diseases.

Efficacy of prophylactic warfarin for prevention of thalidomide-related deep venous thrombosis

BACKGROUND

Deep venous thrombosis (DVT) is a common complication of thalidomide treatment. There is little information to guide clinicians in selecting effective preventive treatments and physician practice varies. We sought to determine whether prophylactic anticoagulation with warfarin prevents DVT related to thalidomide treatment.

METHODS

We reviewed the records of 131 patients receiving thalidomide for a variety of indications. Fifty-five patients were prescribed warfarin with the intent of preventing DVT. Thirty-seven patients received warfarin at a dose of 1-2 mg per day (low dose) and 18 received a dose intended to raise the INR to 2-3 (high dose).

RESULTS

Twenty-one of the 131 patients developed venous thrombosis during thalidomide treatment. Eighteen of the 76 patients (23.7%) who were not prescribed prophylactic anticoagulation developed DVT compared to 3 of the 55 patients (5.5%) who were prescribed any dose of prophylactic warfarin (P = 0.010). Only 1 of the 37 patients who received low-dose warfarin developed DVT (P = 0.011). Bleeding complications occurred in 4 patients, all of whom were receiving high-dose warfarin.

CONCLUSION

Prophylactic anticoagulation with warfarin reduces the risk of thrombosis during thalidomide treatment. Low-dose warfarin may be as effective as higher dose treatment and may result in fewer bleeding complications.

Role of IkappaB kinase in tumorigenesis

IkappaB kinase plays a central role in regulating NF-kappaB, is a key signaling molecule involved in controlling cell proliferation, survival, antiapoptosis, and tumorigenesis. Alternative pathways can also regulate NF-kappaB in an IkappaB kinase-independent manner. Emerging evidence indicates that IKK phosphorylates and inactivates forkhead box, class O (FOXO)-3a and promotes cell growth and tumorigenesis. Moreover, IKK and NF-kappaB play an important role in linking inflammation and tumorigenesis, and facilitate tumor maintenance and invasion. Thus, IKK and NF-kappaB are promising targets for drug discovery, and agents targeting the IKK/NF-kappaB and FOXO pathways may become therapeutic intervention for those patients with IKK/NF-kappaB-overexpressing cancers in the future.

Monoclonal gammopathy of undetermined significance, Waldenström macroglobulinemia, AL amyloidosis, and related plasma cell disorders: diagnosis and treatment

The spectrum of plasma cell disorders is broad. Monoclonal gammopathy of undetermined significance and smoldering multiple myeloma are asymptomatic disorders characterized by monoclonal plasma cell proliferation in the bone marrow in the absence of end-organ damage. Waldenström macroglobulinemia typically involves an ontogenically less mature lymphoplasmacytic bone marrow cell and is characterized by secretion of a monoclonal IgM protein. Solitary plasmacytoma is the only known potentially curable plasma cell disorder. Finally, AL (immunoglobulin light chain) amyloidosis and POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes) syndrome are disorders characterized by low tumor burden but profound multisystemic disease. Updated diagnostic criteria for these disorders, risk stratification models to determine prognosis, and the current management of these diverse entitles are discussed in this review.

Caveolin-1 as a potential new therapeutic target in multiple myeloma

Caveolae are specialized flask-shaped lipid rafts enriched in cholesterol, sphingolipids, and structural marker proteins termed caveolins. Caveolins are highly conserved hairpin loop-shaped, oligomeric proteins of 22-24 kDa. Besides the plasma cell membrane, caveolins are also present in mitochondria, the endoplasmatic reticulum, the Golgi/trans-Golgi network, and secretory vesicles. They play a critical role in normal vesicular transport, cholesterol homeostasis, and signal transduction. Conversely, dysregulation of caveolin-1 has been associated with several human diseases including multiple myeloma, an incurable malignancy characterized by excess monoclonal plasma cells within the bone marrow. In this mini-review, we characterize the functional role of caveolin-1 in multiple myeloma, and present the preclinical rationale for novel potential therapeutic approaches targeting caveolin-1 in multiple myeloma.

Sustained molecular remission by non-myeloablative stem cell transplantation after autologous hematopoietic stem cell transplantation in a patient with multiple myeloma

Multiple myeloma (MM) is refractory to conventional chemotherapy. To achieve a sustained complete remission, we performed planned non-myeloablative allogeneic stem cell transplantation (NST) after autologous hematopoietic stem cell transplantation (HSCT) in a patient with stage III MM. Autologous HSCT was performed using high-dose melphalan after conventional chemotherapy, followed by NST from an HLA-identical sibling using low-dose total body irradiation (200 cGy) for conditioning. Cyclosporine and mycophenolate mofetil were used for graft-vs-host disease (GVHD) prophylaxis. Acute GVHD was transiently seen in the skin and intestine, while, in addition, mild chronic GVHD was seen in the oral mucosa and skin. Complete donor chimerism was achieved and the disappearance of tumor-derived monoclonal B cells was confirmed based on an analysis of immunoglobulin light chain messenger signals on day 156 when chronic GVHD occurred. The clinical course in this case strongly suggested the existence of a graft-vs-myeloma effect.

An interesting cause of esophageal ulcer etiology: Multiple myeloma of IgG kappa subtype

Multiple myeloma is a neoplasm of mature and immature plasma cells. A 50-year-old woman with lumbago, dysphagia, and left arm pain was presented. Upper endoscopical examination was performed. There was an exudate-covered ulcer in the distal esophagus, located at 30-32 cm from the incisors, covering the whole mucosa. Histopathological examination of the specimens obtained from the lesion showed the involvement of plasma cells consistent with multiple myeloma of IgG kappa subtype. Esophageal involvement of multiple myeloma should be kept in mind in patients presenting with dysphagia.

Combined vaccination with idiotype-pulsed allogeneic dendritic cells and soluble protein idiotype for multiple myeloma patients relapsing after reduced-intensity conditioning allogeneic stem cell transplantation

BACKGROUND AND OBJECTIVE

To combine the use of idiotype-pulsed allogeneic dendritic cells (alloDC) and soluble protein Id conjugated with KLH (Id-KLH) in a vaccine strategy for multiple myeloma (MM).

DESIGN AND METHODS

Four MM patients received the combined vaccine after having experienced disease relapse/progression following reduced intensity conditioning (RIC) allogeneic stem cell transplantation (alloSCT) and failure to rescue therapy with donor lymphocyte infusion or chemotherapy (CHT).

RESULTS

Vaccination was well tolerated and induced an anti-KLH antibody response in all 4 patients as well as substantial cell proliferation. In contrast, no case showed similar effects against either tumor-specific Id or irrelevant isotype control immunoglobulins (Ig). In turn, vaccination was associated with modulation of biological responses linked to both inflammatory and T-cell activation, with secretion of effector Th1 cytokines. In particular, an important increase in the spontaneous ex vivo secretion of TNFalpha, IL-6 and IFNgamma as well as IL-2 and IL-10 was frequently observed prior to the fourth vaccination. Moreover, in vitro stimulation with Id-KLH and Id-KLH plus alloDC, but not with alloDC alone was associated with an enhanced number of TNF-alpha+ T-cells and an increased secretion of IFNgamma and IL-2 before the third and fourth vaccination. From a clinical standpoint, 2 patients had a transient response and 1 has stable disease after stopping vaccination, while 3 of them ultimately progressed.

INTERPRETATION AND CONCLUSIONS

The results show for the first time that the use of Id-pulsed alloDC following RIC alloSCT is safe and feasible. However, crucial strategy improvements are warranted to possibly achieve clinical benefit.

Autologous stem cell transplantation followed by consolidation chemotherapy for patients with multiple myeloma

Although high-dose therapy and autologous stem cell transplant (ASCT) is superior to conventional chemotherapy for treatment of myeloma, most patients relapse and the time to relapse depends upon the initial prognostic factors. The administration of non-cross-resistant chemotherapies during the post-transplant period may delay or prevent relapse. We prospectively studied the role of consolidation chemotherapy (CC) after single autologous peripheral blood stem cell transplant (auto-PBSCT) in 103 mostly newly diagnosed myeloma patients (67 patients were < or =6 months from the initial treatment). Patients received conditioning with BCNU, melphalan+/-gemcitabine and auto-PBSCT followed by two cycles of the DCEP+/-G regimen (dexamethasone, cyclophosphamide, etoposide, cisplatin+/-gemcitabine) at 3 and 9 months post-transplant and alternating with two cycles of DPP regimen (dexamethasone, cisplatin, paclitaxel) at 6 and 12 months post-transplant. With a median follow-up of 61.2 months, the median event-free survival (EFS) and overall survival (OS) are 26 and 54.1 months, respectively. The 5-year EFS and OS are 23.1 and 42.5%, respectively. Overall, 51 (49.5%) patients finished all CC, suggesting that a major limitation of this approach is an inability to deliver all planned treatments. In order to improve results following autotransplantation, novel agents or immunologic approaches should be studied in the post-transplant setting.

Advances in oral therapy for multiple myeloma

Conventional intravenous chemotherapy regimens are toxic, cumbersome, and negatively affect patients' quality of life, with oral treatment preferable to most patients with cancer. Multiple myeloma is the second most common haematological malignant disease, but cannot be cured with conventional and high-dose chemotherapy. New oral treatments that target myeloma cells or bone marrow are being developed that are highly effective yet have low toxic effects, such as the immunomodulatory drugs thalidomide and lenalidomide. Several treatments in early development have shown antimyeloma activity, including: CHIR-258, which inhibits fibroblast growth factor receptor 3; NVP-ADW742, which inhibits insulin-like growth factor receptor 1; and PTK787, which inhibits vascular endothelial growth factor. Additional drugs aimed at switching off silenced genes include histone deacetylase inhibitors. The availability of these various oral treatments is hoped to improve regimens that, if used sequentially or in combination, offer the potential of making multiple myeloma a chronic disease, thereby extending patients' lifespans and improving quality of life.

High-resolution genomic profiles define distinct clinico-pathogenetic subgroups of multiple myeloma patients

To identify genetic events underlying the genesis and progression of multiple myeloma (MM), we conducted a high-resolution analysis of recurrent copy number alterations (CNAs) and expression profiles in a collection of MM cell lines and outcome-annotated clinical specimens. Attesting to the molecular heterogeneity of MM, unsupervised classification using nonnegative matrix factorization (NMF) designed for array comparative genomic hybridization (aCGH) analysis uncovered distinct genomic subtypes. Additionally, we defined 87 discrete minimal common regions (MCRs) within recurrent and highly focal CNAs. Further integration with expression data generated a refined list of MM gene candidates residing within these MCRs, thereby providing a genomic framework for dissection of disease pathogenesis, improved clinical management, and initiation of targeted drug discovery for specific MM patients.

Treatment paradigms for the newly diagnosed patient with multiple myeloma

The management of newly diagnosed multiple myeloma is currently being revolutionized by the emergence of novel therapeutic agents. Thalidomide, the thalidomide analogue lenalidomide, and the proteasome inhibitor bortezomib each have potential roles to play in the initial therapy of myeloma that are supported by encouraging clinical trials results. While evaluation for stem cell transplantation (SCT) remains a part of the algorithm for management of the newly diagnosed patient, these drugs offer improved options for induction before, and possibly maintenance after, SCT. For the patient who is not a candidate for SCT the armamentarium for management has been significantly expanded. This review will summarize currently available data regarding these exciting agents and will describe therapeutic strategies currently on the horizon.

Proteasome inhibition: novel therapy for multiple myeloma

Therapeutic options for patients with myeloma are a rapidly advancing area of research due in part to an increase in the understanding of myeloma biology as well as the development of novels agents. Proteasome inhibition is a novel modality for the treatment of patients with myeloma. Bortezomib, a novel proteasome inhibitor, was effective in a broad range of tumor cell lines in preclinical testing. In phase I trials, bortezomib was noted to be active in patients with multiple myeloma and lymphoma. This led to several multicenter trials confirming the safety and efficacy of bortezomib for patients with relapsed and refractory myeloma. Most recently, a large randomized phase III trial comparing bortezomib with high-dose dexamethasone demonstrated that bortezomib had an improved response rate, duration of remission and overall survival advantage in the setting of relapsed disease. These findings have led investigators to study proteasome inhibition with conventional chemotherapy and other novel agents. In addition, several recently completed and ongoing studies are evaluating the role of bortezomib in the initial treatment of myeloma. The success of proteasome inhibition in the treatment of myeloma is a model for effective translation of preclinical research into tangible clinical benefits for patients with cancer.

Vinorelbine plus intermediate dose cyclophosphamide is an effective and safe regimen for the mobilization of peripheral blood stem cells in patients with multiple myeloma

High dose cyclophosphamide (HD-Cy) is commonly used to mobilize stem cells in multiple myeloma (MM). However, timing of collection is variable and incidence of side effects is substantial. We evaluated a combination of vinorelbine (VNB) (25 mg/m(2) day 1) plus Cy (1.5 g/m(2) day 2) and G-CSF as mobilizing regimen in 37 patients with MM. Results were compared to those achieved in 41 previously diagnosed patients mobilized with Cy at 4 g/m(2). Overall, 36/37 patients receiving VNB-Cy (97%) mobilized, as opposed to 40/41 (97%) in the controls (p:0.51). Median CD34+ cells peak was 94/mul for VNB-Cy patients and 96 for controls, p=0.36; median number of CD34+ cells collected was 9.2x10(6)/kg and 8.7x10(6)/kg, respectively (p=0.85). Median number of days to the highest CD34 count was shorter for VNB-Cy patients (nine vs 11, p=0.001). No VNB-Cy patient experienced grade 3-4 neutropenia and thrombocytopenia, as opposed to 63 and 19% in the controls (p=0.001 and 0.01, respectively). Hospitalization from toxicity was never required in VNB-Cy patients as compared to 19% in control group (p=0.01). We conclude that an outpatient combination of VNB plus intermediate dose Cy plus G-CSF is a safe, predictable, and highly effective mobilization regimen for patients with newly-diagnosed MM.

Oral melphalan and prednisone chemotherapy plus thalidomide compared with melphalan and prednisone alone in elderly patients with multiple myeloma: randomised controlled trial

BACKGROUND

Since 1960, oral melphalan and prednisone (MP) has been regarded as the standard of care in elderly multiple myeloma patients. This multicentre randomised trial compared oral MP plus thalidomide (MPT) with MP alone in patients aged 60-85 years.

METHODS

Patients with newly diagnosed multiple myeloma were randomly assigned to receive oral MP for six 4-week cycles plus thalidomide (n=129; 100 mg per day continuously until any sign of relapse or progressive disease) or MP alone (n=126). Analysis was intention-to-treat. This study is registered at , number NCT00232934.

RESULTS

Patients treated with thalidomide had higher response rates and longer event-free survival (primary endpoints) than patients who were not. Combined complete or partial response rates were 76.0% for MPT and 47.6% for MP alone (absolute difference 28.3%, 95% CI 16.5-39.1), and the near-complete or complete response rates were 27.9% and 7.2%, respectively. 2-year event-free survival rates were 54% for MPT and 27% for MP (hazard ratio [HR] for MPT 0.51, 95% CI 0.35-0.75, p=0.0006). 3-year survival rates were 80% for MPT and 64% for MP (HR for MPT 0.68, 95% CI 0.38-1.22, p=0.19). Rates of grade 3 or 4 adverse events were 48% in MPT patients and 25% in MP patients (p=0.0002). Introduction of enoxaparin prophylaxis reduced rate of thromboembolism from 20% to 3% (p=0.005).

CONCLUSION

Oral MPT is an effective first-line treatment for elderly patients with multiple myeloma. Anticoagulant prophylaxis reduces frequency of thrombosis. Longer follow-up is needed to assess effect on overall survival.

Novel therapeutic strategies targeting growth factor signalling cascades in multiple myeloma

Multiple myeloma (MM) remains largely incurable despite conventional and high-dose therapies, and novel biologically based treatment approaches are urgently required. Recent studies demonstrate that various growth factors including interleukin (IL)-6, insulin-like growth factor (IGF)-1, vascular endothelial growth factor (VEGF), the tumour necrosis factor (TNF) family proteins, Wnt, and Notch family members play an important role in MM pathogenesis, and mediate tumour cell proliferation, drug resistance and migration in the bone marrow (BM) milieu. Targeting growth factors, therefore, represents a promising therapeutic strategy in MM. Novel agents inhibiting growth factor signalling cascades can target ligands, receptors, and/or downstream signalling cascade proteins in MM cells and the BM microenvironment. Combinations of these novel agents with conventional therapies may not only enhance cytotoxicity, but also avoid drug resistance and thereby improve patient outcome in MM.

Cutaneous leucoclastic vasculitis (LV) following bortezomib therapy in a myeloma patient; association with pro-inflammatory cytokines

The proteasome inhibitor, bortezomib, has anti-myeloma activity even in myeloma cells refractory to multiple prior treatments. Bortezomib blocks the production of nuclear factor-kappaB (NFkappaB)-mediated pro-inflammatory cytokines. We report a patient with myeloma who developed a cutaneous leucoclastic vasculitis (LV) after bortezomib treatment. The patient with LV exhibited a marked increase in serum levels of IL-6, TNF-alpha, and C-reactive protein (CRP). Bortezomib administration may enhance the release of pro-inflammatory cytokines, which might play a role in bortezomib-induced cutaneous LV.

First-line therapy with thalidomide, dexamethasone and zoledronic acid decreases bone resorption markers in patients with multiple myeloma

BACKGROUND

Bone involvement is frequently observed in multiple myeloma (MM) patients both at diagnosis and during the course of the disease. The evaluation of biochemical markers of bone turnover could allow a dynamic evaluation of the effects of a given therapy on bone metabolism.

METHODS

In the present study, markers of bone resorption [urinary free pyridinoline (PYD), deoxypyridinoline (DPYD), N-terminal telopeptide of collagen I (NTX) and C-terminal telopeptide (serum crosslaps)] and of bone formation [bone alkaline phosphatase (BAP) and osteocalcin] were evaluated at diagnosis and after induction therapy in 40 patients (23M, 17F, median age = 53.5 yr) enrolled in the 'Bologna 2002' clinical trial. By study design, all patients received 4 months of combined thalidomide (100 mg/d for 2 wk then 200 mg/d), dexamethasone (40 mg/d on days 1-4, 9-12, 17-20/28 on odd cycles and on days 1-4 on even cycles) and zoledronic acid (4 mg/28 d).

RESULTS

At diagnosis, although bone resorption markers were increased in more than 40% of the patients, only NTX (P = 0.029) and crosslaps (P = 0.000) were significantly related to the extent of skeletal lesions, as assessed by X-ray. After 4 months of therapy, a significant decrease in mean (+/-SE) urinary NTX (52.7 +/-6.9 nmol/mmol creatinine +/-6.9 vs. 14 +/- 1.42 nmol/mmol creatinine, P = 0.000) and serum crosslaps (6242.4 +/-945 pmol/L vs. 1414.9 +/- 173.8 pmol/L, P = 0.000) was observed in patients obtaining > or =partial response, at variance to what has been detected in patients showing <partial response.

CONCLUSIONS

Among all bone resorption markers, urinary NTX and serum crosslaps seem to be strictly related to the extent of bone involvement in MM. Combined thalidomide + dexamethasone and zoledronic acid seem to be highly effective in reducing bone resorption in sensitive patients, although the relative contribution of each drug cannot yet be determined.

Construction of a conventional non-radioisotope method to quantify HM1.24 antigens: correlation of HM1.24 levels and ADCC activity of the humanized antibody against HM1.24

A humanized monoclonal antibody (mAb) against HM1.24 (AHM) caused antibody-dependent cellular cytotoxicity (ADCC) against multiple myeloma (MM) cells. Here, we constructed a conventional non-radioisotope method that quantifies the amount of HM1.24 using fluorescein-labeled AHM. More than 10(4) molecules/cell of HM1.24 were detected in 12 out of 14 patients' MM cells, and a linear correlation was found between ADCC by AHM and the amounts of HM1.24. Thus, AHM is likely to be more efficacious against MM cells with high levels of HM1.24. This conventional non-RI method to quantify HM1.24 will be useful to select patients most likely to respond to AHM.

Evaluation of a new capillary zone electrophoresis system for the identification and typing of Bence Jones Protein

OBJECTIVES

Capillary electrophoresis has recently emerged as a new sensitive technique for the separation of urinary proteins. We evaluated a new method for Bence Jones Protein (BJP) detection and characterization on native urine samples by the Paragon CZE 2000 system. To avoid interference in electrophoretic separation, urine samples were preliminarily treated for the selective removal of interfering salt particles.

DESIGN AND METHODS

The evaluation was done on a total of 350 fresh 24-h urine samples. The salt particle removal consisted of a manual chromatographic separation, optimized in the course of our evaluation. Capillary zone urinary protein electrophoresis (CZ-UPE) was compared with conventional high-resolution electrophoresis on an agarose gel, while capillary immunosubtraction (CZU-IFE) was compared with agarose gel immunofixation.

RESULTS

After finding a consistent protein loss in eluates, the preanalytical treatment was optimized by changing sample dilution and eluate collection. The within- and between-run imprecision values for monoclonal peaks corresponding to BJP ranged from 0.4-12.2% to 3.3-6.3%, respectively. The detection limit for BJP, defined as the lowest measurable monoclonal peak on CZ-UPE, was 0.0012 g/L for kappa BJP and 0.0007 g/L for lambda BJP. CZ-UPE and CZU-IFE sensitivities were significantly lower in urine samples with a total protein level < or = 100 mg/L (67% and 78%, respectively) compared to those with total protein >100 mg/L (92% and 94%, respectively). Comparison between BJP measurements obtained from densitometric scanning with those from absorbance tracing showed a correlation coefficient of 0.994 and a bias of 29.8 mg/L.

CONCLUSIONS

Paragon CZE 2000 can be introduced in routine for screening and typing of BJP; in urine samples with a total protein level >100 mg/L, the performance is consistent with results from published validation studies on CZE applied to serum samples.