Treatment of multiple myeloma

Aptamer TY04 inhibits the growth of multiple myeloma cells via cell cycle arrest

The aptamer TY04 is a single-stranded DNA. However, its biological function has not been elucidated. Here, we found that TY04 specifically bound to multiple myeloma cells MM.1S, and some membrane proteins on the surface of MM.1S cells constituted the target molecules of TY04. TY04 inhibited the growth of multiple myeloma cell lines, induced cell cycle arrest in mitosis, and resulted in a significant accumulation of binucleated cells. Following TY04 treatment, a concomitant increase in CDK1 and cyclin B1 expression occurred. In addition, TY04 treatment also resulted in a significant downregulation of γ-tubulin. Considering the unique advantages of aptamers, TY04 shows great potential as a drug candidate to treat multiple myeloma.

Successful treatment of bortezomib-refractory multiple myeloma derived from monoclonal gammopathy of undetermined significance with dose-adjusted lenalidomide therapy in a patient with concomitant end-stage renal disease due to diabetic nephropathy requiring haemodialysis

Malignancy is a fatal complication of end-stage renal disease (ESRD) requiring haemodialysis. However, the successful treatment of haematological malignancies has been rarely reported. We describe the case of a 63-year-old man who presented with IgA-type multiple myeloma (MM; Durie-Salmon stage IIIB) derived from monoclonal gammopathy of undetermined significance concomitant with ESRD due to diabetic nephropathy. First, haemodialysis was initiated before chemotherapy, and bortezomib and dexamethasone were found to be ineffective. Subsequently, 8 courses of dose-adjusted lenalidomide therapy were administered according to the degree of haematological and renal functions. The patient remained in partial remission without disease progression for 21 months. Thus, lenalidomide therapy is effective for bortezomib-refractory MM concomitant with ESRD.

The work of living with a rare cancer: multiple myeloma

AIM

To report findings from a qualitative study of the experiences of long-term survivors of multiple myeloma.

BACKGROUND

Multiple Myeloma is a malignant disease of the bone marrow. Until recently, it was rapidly fatal. Although it remains incurable, people diagnosed with it are living longer on average, largely due to new treatments, some of which have onerous side effects.

DESIGN

Prospective descriptive study.

METHOD

A series of 47 in-depth interviews were conducted at 6-12 month intervals over 18 months in 2008-2010 with 10 long-term survivors of myeloma and their primary support person. Interviews were analysed using the constant comparative method (Grounded Theory).

FINDINGS

To adapt to the effects of both the disease and ongoing medical treatments, participants undertook extensive 'illness work'. Most of this work fell into two broad categories. Risk work aimed to mitigate risks to the well-being of both the person with myeloma and his/her carer. Emotion work aimed to manage the feelings of self and others in a protracted cycle of remission and relapse.

CONCLUSION

The experience of myeloma is increasingly characterized by issues associated with chronic disease and 'survivorship'. It is important for nurses working with people with myeloma to understand the overwhelming nature of illness work in this context. Nurses can put in place supportive measures to address the two main 'drivers' of this work: constant risk to well-being of survivors (including carers) and the recurrent need to manage emotions in social interactions.

Effectiveness of targeted therapy as monotherapy or combined therapy in patients with relapsed or refractory multiple myeloma: a systematic review and meta-analysis

OBJECTIVES

The aim of this systematic review was to evaluate the efficacy and safety of targeted agents used as monotherapy or combined therapy in patients with relapsed/refractory multiple myeloma (MM).

METHODS

The systematic literature search was conducted in PubMed, Embase, Cochrane Library till 27 May 2013.

RESULTS

Four randomized controlled trials were included. The meta-analysis showed that combined therapy significantly improved progression-free survival compared with monotherapy (P < 0.05). However, there was not a significant difference between monotherapy and combined therapy in overall survival (P > 0.05). The combined therapy also significantly increased the risk of serious adverse events and grade 3/4 AEs compared to monotherapy (P < 0.05). Overall, the results of comparisons between monotherapy and combined therapy in individual trials were differentiated, and some combinations were not more effective than monotherapy (bortezomib plub bevacizumab vs. bortezomib and thalidomide plus INFα vs. thalidomide) which emphasizes the role of individualized therapy in relapsed/refractory MM especially in the elderly or patients with significant comorbidities.

CONCLUSIONS

The results of this meta-analysis showed that combined therapy is superior to monotherapy only in some end points and it is less tolerated in patients with relapsed/refractory MM. Thus, the overall superiority of complex therapy to monotherapy depends on the combination of the targeted agents.

Plasmablastic myeloma presenting as rapidly progressive renal failure in a young adult

Multiple myeloma (MM) is a condition where there is malignant proliferation of plasma cells. There is a strong correlation with age, peaking at 60-70 years. The clinical course in adolescents and young individuals is generally indolent and the survival is longer. We report a case of a 28-year-old male, who was diagnosed to have plasmablastic myeloma, an atypical variant of MM with a poor prognosis, presenting as rapidly progressive renal failure. He was given induction chemotherapy and then underwent autologous peripheral blood stem cell transplantation.

Relationship between initial clinical presentation and the molecular cytogenetic classification of myeloma

Multiple myeloma (MM) consists of several distinct cytogenetic subtypes, and we hypothesized that each subtype may have a unique mode of initial presentation and end-organ damage. We studied 484 patients with newly diagnosed MM to determine the relationship between specific myeloma-defining event (MDE) and the cytogenetic subtype. Patients were divided into four non-overlapping groups based on the MDE at diagnosis: isolated renal failure, isolated anemia, isolated lytic bone disease or a combination (mixed). MM with translocations without trisomies accounted for 30% of all patients, but accounted for 50% of patients with renal failure. Specifically, the t(14;16) translocation accounted for only 5% of all MM patients, but was present in 13.5% of patients with renal failure as MDE. Among patients with t(14;16), 25% presented with renal failure only as MDE. Patients with isolated renal failure as MDE had significantly poorer survival compared with all other groups, whereas patients with bone disease as MDE had the best outcome (P<0.001). Our findings support the hypothesis that in addition to prognostic differences, there is significant heterogeneity in clinical presentation associated with the cytogenetic subtype, suggesting that MM encompasses a group of cytogenetically and phenotypically distinct disorders rather than a single entity.

In vitro and in vivo anti-tumor activity of miR-221/222 inhibitors in multiple myeloma

A rising body of evidence suggests that silencing microRNAs (miRNAs) with oncogenic potential may represent a successful therapeutic strategy for human cancer. We investigated the therapeutic activity of miR-221/222 inhibitors against human multiple myeloma (MM) cells. Enforced expression of miR-221/222 inhibitors triggered in vitro anti-proliferative effects and up-regulation of canonic miR-221/222 targets, including p27Kip1, PUMA, PTEN and p57Kip2, in MM cells highly expressing miR-221/222. Conversely, transfection of miR-221/222 mimics increased S-phase and down-regulated p27Kip1 protein expression in MM with low basal miR-221/222 levels. The effects of miR-221/222 inhibitors was also evaluated in MM xenografts in SCID/ NOD mice. Significant anti-tumor activity was achieved in xenografted mice by the treatment with miR-221/222 inhibitors, together with up-regulation of canonic protein targets in tumors retrieved from animals. These findings provide proof of principle that silencing the miR-221/222 cluster exerts significant therapeutic activity in MM cells with high miR-221/222 level of expression, which mostly occurs in TC2 and TC4 MM groups. These findings suggest that MM genotyping may predict the therapeutic response. All together our results support a framework for clinical development of miR-221/222 inhibitors-based therapeutic strategy in this still incurable disease.

Anticancer activity in human multiple myeloma U266 cells: synergy between cryptotanshinone and arsenic trioxide

Arsenic trioxide (As2O3) has been recently established as one of the most effective drugs for the treatment of patients with acute promyelocytic leukemia. However, it has exhibited to be less efficient for the non-promyelocytic leukaemia or other types of malignant tumors. The purpose of the present study was to explore new therapeutic strategies based on As2O3 for human multiple myeloma. Here, we first report cryptotanshinone (CPT) and As2O3 synergy for enhanced cytotoxicity in human multiple myeloma U266 cells. In particular, the apoptosis related proteins (e.g., cleaved poly (ADP-ribose) polymerase (PARP), caspase-3 and -9) were significantly increased by the combination treatment (iAs(III) + CPT), whereas, the expression of survival proteins such as Bcl-2 and survivin was suppressed, suggesting that the induction of apoptosis through mitochondrial-mediated apoptotic pathway. In addition, there were no appreciable effects observed in cells after exposure to either As2O3 or CPT alone. In order to better understand the molecular mechanism, we further determined the phosphorylation of STAT3, JNK, ERK and p38. Interestingly, phosphorylation of JNK and p38 were remarkably induced by combination treatment, and no significant inhibition of STAT3 or ERK was observed. In addition, induction of apoptosis in human multiple myeloma cells was partially abrogated only by pretreatment with JNK inhibitor and not by p38 inhibitor, suggesting that JNK pathway may play an important role in induction of apoptosis by the combination of iAs(III) and CPT. Further studies are needed to evaluate this synergistic anticancer effect in vivo. In the near future, this new approach might be used clinically for multiple myeloma (MM) treatment.

Racial disparities in the prevalence of monoclonal gammopathies: a population-based study of 12,482 persons from the National Health and Nutritional Examination Survey

Multiple myeloma (MM) incidence is markedly higher in blacks compared with whites, which may be related to a higher prevalence of monoclonal gammopathy of undetermined significance (MGUS). Our objective was to define the prevalence and risk factors of MGUS in a large cohort representative of the US population. Stored serum samples from the National Health and Nutritional Examination Survey (NHANES) III or NHANES 1999-2004 were available for 12,482 individuals of age ⩾50 years (2331 'blacks', 2475 Hispanics, 7051 'whites' and 625 'others') on which agarose-gel electrophoresis, serum protein immunofixation, serum-free light-chain assay and M-protein typing were performed. MGUS was identified in 365 participants (2.4%). Adjusted prevalence of MGUS was significantly higher (P<0.001) in blacks (3.7%) compared with whites (2.3%) (P=0.001) or Hispanics (1.8%), as were characteristics that posed a greater risk of progression to MM. The adjusted prevalence of MGUS was 3.1% and 2.1% for the North/Midwest versus South/West regions of the United States, respectively (P=0.052). MGUS is significantly more common in blacks, and more often has features associated with higher risk of progression to MM. A strong geographic disparity in the prevalence of MGUS between the North/Midwest versus the South/West regions of the United States was found, which has etiologic implications.

GSK3-mediated MAF phosphorylation in multiple myeloma as a potential therapeutic target

Multiple myeloma (MM) is an incurable haematological malignancy characterised by the proliferation of mature antibody-secreting plasma B cells in the bone marrow. MM can arise from initiating translocations, of which the musculoaponeurotic fibrosarcoma (MAF) family is implicated in ∼5%. MMs bearing Maf translocations are of poor prognosis. These translocations are associated with elevated Maf expression, including c-MAF, MAFB and MAFA, and with t(14;16) and t(14;20) translocations, involving c-MAF and MAFB, respectively. c-MAF is also overexpressed in MM through MEK/ERK activation, bringing the number of MMs driven by the deregulation of a Maf gene close to 50%. Here we demonstrate that MAFB and c-MAF are phosphorylated by the Ser/Thr kinase GSK3 in human MM cell lines. We show that LiCl-induced GSK3 inhibition targets these phosphorylations and specifically decreases proliferation and colony formation of Maf-expressing MM cell lines. Interestingly, bortezomib induced stabilisation of Maf phosphorylation, an observation that could explain, at least partially, the low efficacy of bortezomib for patients carrying Maf translocations. Thus, GSK3 inhibition could represent a new therapeutic approach for these patients.

Steroid-resistant nephrotic syndrome secondary to primary focal segmental glomerulosclerosis and smoldering multiple myeloma

We present a patient with steroid-resistant nephrotic syndrome due to focal segmental glomerulosclerosis along with smoldering multiple myeloma. While investigating the cause of proteinuria, a monoclonal gammopathy with a negative kidney biopsy for myeloma-related pathology was discovered.

Smoldering multiple myeloma requiring treatment: time for a new definition?

Smoldering multiple myeloma (SMM) bridges the gap between monoclonal gammopathy of undetermined significance (a mostly premalignant disorder) and active multiple myeloma (MM). Until recently, no interventional study in patients with SMM showed improved overall survival (OS) with therapy as compared with observation. A report from the PETHEMA-GEM (Programa Español de Tratamientos en Hematologica) group described both fewer myeloma-related events and better OS among patients with high-risk SMM who were treated with lenalidomide and dexamethasone. This unique study prompted us to review current knowledge about SMM and address the following questions: (1) Are there patients currently defined as SMM who should be treated routinely? (2) Should the definitions of SMM and MM be reconsidered? (3) Has the time come when not treating is more dangerous than treating? (4) Could unintended medical harm result from overzealous intervention? Our conclusion is that those patients with the highest-risk SMM (extreme bone marrow plasmacytosis, extremely abnormal serum immunoglobulin free light chain ratio, and multiple bone lesions detected only by modern imaging) should be reclassified as active MM so that they can receive MM-appropriate therapy and the paradigm of careful observation for patients with SMM can be preserved.

Responsiveness of cytogenetically discrete human myeloma cell lines to lenalidomide: lack of correlation with cereblon and interferon regulatory factor 4 expression levels

The introduction of novel immunomodulatory drugs (IMiDs) has dramatically improved the survival of patients with multiple myeloma (MM). While it has been shown that patients with specific cytogenetic subtypes, namely t(4;14), have the best outcomes when treated with bortezomib-based regimens, the relationship between cytogenetic subtypes and response to IMiDs remains unclear. Using DNA synthesis assays, we investigated the relationship between cytogenetic subtype and lenalidomide response in a representative panel of human myeloma cell lines (HMCLs). We examined HMCL protein expression levels of the lenalidomide target cereblon (CRBN) and its downstream target interferon regulatory factor-4 (IRF4), which have previously been shown to be predictive of lenalidomide response in HMCLs. Our results reveal that lenalidomide response did not correlate with specific cytogenetic translocations. There were distinct groups of lenalidomide-responsive and non-responsive HMCLs, as defined by inhibition of cellular proliferation; notably, all of the hyperdiploid HMCLs fell into the latter category. Repeated dosing of lenalidomide significantly lowered the IC50 of the responsive HMCL ALMC-1 (IC50 = 2.6 μm vs. 0.005 μm, P < 0.0001), but did not have an effect on the IC50 of the non-responsive DP-6 HMCL (P > 0.05). Moreover, no association was found between lenalidomide responsiveness and CRBN and IRF4 expression. Our data indicate that lenalidomide sensitivity is independent of cytogenetic subtype in HMCLs. While CRBN and IRF4 have been shown to be associated with response to lenalidomide in patients, these findings do not translate back to HMCLs, which could be attributable to factors present in the bone marrow microenvironment.

Second transplants for multiple myeloma relapsing after a previous autotransplant-reduced-intensity allogeneic vs autologous transplantation

There is no standard therapy for multiple myeloma relapsing after an autotransplant. We compared the outcomes of a second autotransplant (N=137) with those of an allotransplant (N=152) after non-myeloablative or reduced-intensity conditioning (NST/RIC) in 289 subjects reported to the CIBMTR from 1995 to 2008. NST/RIC recipients were younger (median age 53 vs 56 years; P<0.001) and had a shorter time to progression after their first autotransplant. Non-relapse mortality at 1-year post transplant was higher in the NST/RIC cohort, 13% (95% confidence interval (CI), 8-19) vs 2% (95% CI, 1-5, P0.001). Three-year PFS and OS for the NST/RIC cohort were 6% (95% CI, 3-10%) and 20% (95% CI, 14-27%). Similar outcomes for the autotransplant cohort were 12% (95% CI, 7-19%, P=0.038) and 46% (95% CI, 37-55%, P=0.001). In multivariate analyses, risk of death was higher in NST/RIC recipients (hazard ratio (HR) 2.38 (95% CI, 1.79-3.16), P<0.001), those with Karnofsky performance score<90 (HR 1.96 (95% CI, 1.47-2.62), P<0.001) and transplant before 2004 (HR 1.77 (95% CI, 1.34-2.35) P0.001). In conclusion, NST/RIC was associated with higher TRM and lower survival than an autotransplant. As disease status was not available for most allotransplant recipients, it is not possible to determine which type of transplant is superior after autotransplant failure.

High-risk multiple myeloma: different definitions, different outcomes?

Multiple myeloma (MM) is a clonal plasma cell malignancy. Although MM is still not completely curable, it can be maintained at the level of a long-term chronic condition. Irrespective of the treatment strategy, relapse is still a major problem for most patients. Approximately 10% to 15% of all MM patients relapse early and have poor prognosis and outcome. Currently, there are many ways of identifying these high-risk patients using cytogenetics or molecular biology. Despite these various approaches to definition of high risk patients, a clear definition of high-risk MM has not been widely accepted. In this review, we discuss and compare various approaches, and their strengths and weaknesses in early identification of high-risk MM patients.

Towards the integration, annotation and association of historical microarray experiments with RNA-seq

Background

Transcriptome analysis by microarrays has produced important advances in biomedicine. For instance in multiple myeloma (MM), microarray approaches led to the development of an effective disease subtyping via cluster assignment, and a 70 gene risk score. Both enabled an improved molecular understanding of MM, and have provided prognostic information for the purposes of clinical management. Many researchers are now transitioning to Next Generation Sequencing (NGS) approaches and RNA-seq in particular, due to its discovery-based nature, improved sensitivity, and dynamic range. Additionally, RNA-seq allows for the analysis of gene isoforms, splice variants, and novel gene fusions. Given the voluminous amounts of historical microarray data, there is now a need to associate and integrate microarray and RNA-seq data via advanced bioinformatic approaches.

Methods

Custom software was developed following a model-view-controller (MVC) approach to integrate Affymetrix probe set-IDs, and gene annotation information from a variety of sources. The tool/approach employs an assortment of strategies to integrate, cross reference, and associate microarray and RNA-seq datasets.

Results

Output from a variety of transcriptome reconstruction and quantitation tools (e.g., Cufflinks) can be directly integrated, and/or associated with Affymetrix probe set data, as well as necessary gene identifiers and/or symbols from a diversity of sources. Strategies are employed to maximize the annotation and cross referencing process. Custom gene sets (e.g., MM 70 risk score (GEP-70)) can be specified, and the tool can be directly assimilated into an RNA-seq pipeline.

Conclusion

A novel bioinformatic approach to aid in the facilitation of both annotation and association of historic microarray data, in conjunction with richer RNA-seq data, is now assisting with the study of MM cancer biology.

Bortezomib for the treatment of previously untreated multiple myeloma

Management of multiple myeloma (MM) has been drastically changed in the last 10 years thanks to the introduction of novel agents, which, combined with the backbone of classical chemotherapy, have led to a significant improvement in disease control. Bortezomib is the first reversible proteasome inhibitor approved for the treatment of MM, with wide synergism in vitro and in vivo with a plethora of drugs active for MM. In patients eligible for autologous stem cell transplantation (ASCT), the achievement of complete response or very good partial response before ASCT is associated with prolonged progression-free and overall survival. Thus, the goal of induction regimens should include, at least for younger patients, a continued improvement of the quality and depth of the achieved response. This article is focused on reviewing the major efforts in frontline therapy for MM, including bortezomib-containing induction regimens in patients either eligible or ineligible for ASCT.

Poly(ADP-ribose) polymerase family member 14 (PARP14) is a novel effector of the JNK2-dependent pro-survival signal in multiple myeloma

Regulation of cell survival is a key part of the pathogenesis of multiple myeloma (MM). Jun N-terminal kinase (JNK) signaling has been implicated in MM pathogenesis, but its function is unclear. To elucidate the role of JNK in MM, we evaluated the specific functions of the two major JNK proteins, JNK1 and JNK2. We show here that JNK2 is constitutively activated in a panel of MM cell lines and primary tumors. Using loss-of-function studies, we demonstrate that JNK2 is required for the survival of myeloma cells and constitutively suppresses JNK1-mediated apoptosis by affecting expression of poly(ADP-ribose) polymerase (PARP)14, a key regulator of B-cell survival. Strikingly, we found that PARP14 is highly expressed in myeloma plasma cells and associated with disease progression and poor survival. Overexpression of PARP14 completely rescued myeloma cells from apoptosis induced by JNK2 knockdown, indicating that PARP14 is critically involved in JNK2-dependent survival. Mechanistically, PARP14 was found to promote the survival of myeloma cells by binding and inhibiting JNK1. Moreover, inhibition of PARP14 enhances the sensitization of MM cells to anti-myeloma agents. Our findings reveal a novel regulatory pathway in myeloma cells through which JNK2 signals cell survival via PARP14, and identify PARP14 as a potential therapeutic target in myeloma.

The clinical significance of cereblon expression in multiple myeloma

Cereblon (CRBN) mediates immunomodulatory drug (IMiD) action in multiple myeloma (MM). We demonstrate here that no patient with very low CRBN expression responded to IMiD plus dexamethasone therapy. In 53 refractory MM patients treated with pomalidomide and dexamethasone, CRBN levels predict for decreased response rates and significant differences in PFS (3.0 vs. 8.9 months, p<0.001) and OS (9.1 vs. 27.2 months, p=0.01) (lowest quartile vs. highest three quartiles). While higher CRBN levels can serve as a surrogate for low risk disease, our study demonstrates that low CRBN expression can predict resistance to IMiD monotherapy and is a predictive biomarker for survival outcomes.

Differences in the distribution of cytogenetic subtypes between multiple myeloma patients with and without a family history of monoclonal gammopathy and multiple myeloma

We previously reported an increased risk of monoclonal gammopathy of undetermined significance (MGUS) in first-degree relatives of MGUS and multiple myeloma patients. Here, we examine whether primary cytogenetic categories of myeloma differ between patients with and without a family history of MGUS or myeloma. We studied 201 myeloma patients with available data on family history and molecular cytogenetic classification. Myeloma with trisomies was more common in probands who had an affected first-degree relative with MGUS or myeloma compared with those without a family history (46.9% vs. 33.5%, P = 0.125); however, the difference was not statistically significant. Additional studies on the cytogenetic types of myeloma associated with familial tendency are needed.

Residual malignant and normal plasma cells shortly after high dose melphalan and stem cell transplantation. Highlight of a putative therapeutic window in Multiple Myeloma?

Multiple Myeloma (MM) is an incurable malignant plasma cell disorder. We have evaluated the counts of Multiple Myeloma Cells (MMCs) and normal plasma cells (N-PCs), seven days after high-dose melphalan (HDM) and autologous stem transplantation (ASCT). Two third of patients had detectable minimal residual disease (MRD⁺) (71.7 MMCs/μL) after induction treatment with dexamethasone and proteasome inhibitor. MMC counts were reduced by 92% (P ≤ .05) but not eradicated 7 days after HDM+ASCT. Post-HDM+ASCT MMCs were viable and bathed in a burst of MMC growth factors, linked with post-HDM aplasia. In one third of patients (MRD⁻ patients), MMCs were not detectable after induction treatment and remained undetectable after HDM+ASCT. Major difference between MRD⁻ and MRD⁺ patients is that N-PC counts were increased 3 fold (P < .05) by HDM+ASCT in MRD⁻ patients, but were unaffected in MRD⁺ patients. Possible explanation could be that clearance of MMCs in MRD⁻ patients makes more niches available for N-PCs. Thus, MMCs are not fully eradicated shortly after HDM, are bathed in high concentrations of MMC growth factors in an almost desert BM, are viable in short-term culture, which suggests providing additional therapies shortly after HDM to kill resistant MMCs before full repair of lesions.

Ex-vivo dynamic 3-D culture of human tissues in the RCCS™ bioreactor allows the study of Multiple Myeloma biology and response to therapy

Three-dimensional (3-D) culture models are emerging as invaluable tools in tumor biology, since they reproduce tissue-specific structural features and cell-cell interactions more accurately than conventional 2-D cultures. Multiple Myeloma, which depends on myeloma cell-Bone Marrow microenvironment interactions for development and response to drugs, may particularly benefit from such an approach. An innovative 3-D dynamic culture model based on the use of the RCCS™ Bioreactor was developed to allow long-term culture of myeloma tissue explants. This model was first validated with normal and pathological explants, then applied to tissues from myeloma patients. In all cases, histological examination demonstrated maintenance of viable myeloma cells inside their native microenvironment, with an overall well preserved histo-architecture including bone lamellae and vessels. This system was then successfully applied to evaluate the cytotoxic effects exerted by the proteasome inhibitor Bortezomib not only on myeloma cells but also on angiogenic vessels. Moreover, as surrogate markers of specialized functions expressed by myeloma cells and microenvironment, β2 microglobulin, VEGF and Angiopoietin-2 levels, as well as Matrix Metalloproteases activity, were evaluated in supernatants from 3D cultures and their levels reflected the effects of Bortezomib treatment. Notably, determination of β2 microglobulin levels in supernatants from Bortezomib-treated samples and in patients'sera following Bortezomib-based therapies disclosed an overall concordance in the response to the drug ex vivo and in vivo.

Our findings indicate, as a proof of principle, that 3-D, RCCS™ bioreactor-based culture of tissue explants can be exploited for studying myeloma biology and for a pre-clinical approach to patient-targeted therapy.

IMWG consensus on risk stratification in multiple myeloma

Multiple myeloma is characterized by underlying clinical and biological heterogeneity, which translates to variable response to treatment and outcome. With the recent increase in treatment armamentarium and the projected further increase in approved therapeutic agents in the coming years, the issue of having some mechanism to dissect this heterogeneity and rationally apply treatment is coming to the fore. A number of robustly validated prognostic markers have been identified and the use of these markers in stratifying patients into different risk groups has been proposed. In this consensus statement, the International Myeloma Working Group propose well-defined and easily applicable risk categories based on current available information and suggests the use of this set of prognostic factors as gold standards in all clinical trials and form the basis of subsequent development of more complex prognostic system or better prognostic factors. At the same time, these risk categories serve as a framework to rationalize the use of therapies.

DNA repair pathways in human multiple myeloma: role in oncogenesis and potential targets for treatment

Every day, cells are faced with thousands of DNA lesions, which have to be repaired to preserve cell survival and function. DNA repair is more or less accurate and could result in genomic instability and cancer. We review here the current knowledge of the links between molecular features, treatment, and DNA repair in multiple myeloma (MM), a disease characterized by the accumulation of malignant plasma cells producing a monoclonal immunoglobulin. Genetic instability and abnormalities are two hallmarks of MM cells and aberrant DNA repair pathways are involved in disease onset, primary translocations in MM cells, and MM progression. Two major drugs currently used to treat MM, the alkylating agent Melphalan and the proteasome inhibitor Bortezomib act directly on DNA repair pathways, which are involved in response to treatment and resistance. A better knowledge of DNA repair pathways in MM could help to target them, thus improving disease treatment.

A randomized phase II trial of fludarabine/melphalan 100 versus fludarabine/melphalan 140 followed by allogeneic hematopoietic stem cell transplantation for patients with multiple myeloma

Allogeneic hematopoietic stem cell transplantation (allo-HCT) is a potentially curative treatment for multiple myeloma (MM); however, because of high treatment-related mortality (TRM), its role is not well defined. Patients with newly diagnosed, relapsed, or primary refractory myeloma were enrolled in a randomized phase II trial of 2 reduced-intensity conditioning regimens: fludarabine 120 mg/m(2) + melphalan 100 mg/m(2) (FM100) versus fludarabine 120 mg/m(2) + melphalan 140 mg/m(2) (FM140) before allo-HCT from related or unrelated donors. Fifty patients underwent allo-HCT using FM100 (n = 23) or FM140 (n = 27) conditioning between April 2002 and 2011. There were no significant differences between FM100 and FM140 in time to neutrophil engraftment (P = .21), acute grade II to IV graft-versus-host disease (GVHD) (P = 1.0), chronic GVHD (P = .24), response rate (P = 1.0), TRM (13% versus 15%, P = 1.0), median progression-free survival (PFS), 11.7 versus 8.4 months, P = .12, and median overall survival (OS), 35.1 versus 19.7 months, P = .38. Cumulative incidence of disease progression in FM100 and FM140 was 43% and 70%, respectively (P = .08). Recurrent disease was the most common cause of death for both FM100 (26%) and FM140 (44%), P = .24. On multivariate analysis, disease status at allo-HCT, complete response or very good partial response (VGPR) was significantly associated with longer PFS (15.6 versus 9.6 months in patients with <VGPR, P = .05). OS was similar across all variables. We conclude that FM100 and FM140 may result in similar patient outcomes after allo-HCT for MM.

Validation of the Freiburg Comorbidity Index in 466 multiple myeloma patients and combination with the international staging system are highly predictive for outcome

BACKGROUND

The outcomes of MM patients vary considerably and depend on a variety of host- and disease-related risks. As yet, a comorbidity risk index in MM patients has neither been standardized nor validated.

PATIENTS AND METHODS

We conducted an initial analysis in 127 MM patients and developed the FCI, validating it in an independent cohort of 466 MM patients. The FCI includes patients' Karnofsky Performance Status, renal and lung disease status. We compared the prognostic information of this validated FCI with established comorbidity indices (Hematopoietic Cell Transplantation-Specific Comorbidity Index and Kaplan Feinstein), the International Staging System (ISS), MM therapy, and age.

RESULTS

Our validation confirmed that patients with 0, 1, or 2 to 3 FCI risk factors display significantly different overall survival (OS) of not reached, 86, and 39 months, respectively (P < .0001). Via multivariate analysis including the FCI, ISS, therapy, and age, the FCI retained its independent prognostic significance (P < .0015). The combination of the FCI and ISS allowed definition of 3 distinct subgroups with low-risk (FCI 0 and ISS I-II), intermediate-risk (all remaining), and high-risk (FCI 1-3 and ISS III) with OS probabilities at 5-years of 85%, 74%, and 42%, respectively (P < .0001).

CONCLUSION

Our validation analysis demonstrated that the FCI remains a reliable comorbidity index, is simpler to generate than other available comorbidity scores, and contributes valuable information to the ISS. Their combination allows the definition of low-, intermediate-, and high-risk patients. These results advocate use of the FCI in future prospective studies and might guide personalized treatment strategies.

Occurrence of multiple myeloma in the head and neck: a report of two cases

Multiple myeloma (MM) is a disease reported to account for 1% of all cancers and 10% of hematological malignant diseases. Unlike other malignant diseases that are transferred to the osseous tissues, MM does not show new bone formation, is associated with characteristic osteolytic lesions, and shows monoclonal protein (M-protein) on the immunohematological test, which is an important index in its diagnosis. Solitary lesions of MM are rare in the head and neck area, and, in most cases, MM of the head and neck area is related to systemic sympomts.

Emerging pathways as individualized therapeutic target of multiple myeloma

INTRODUCTION

Multiple myeloma (MM) is an incurable plasma cell malignancy, which causes significant morbidity due to organ damage and bone tissue destruction. In recent years, novel drugs have become available for MM therapy thanks to the growing knowledge of disease pathobiology.

AREAS COVERED

Intrinsic genetic lesions, as well as the bone marrow microenvironment, contribute to the activation of proliferation and survival pathways, impairment of cell death mechanisms and drug resistance. The phosphatidylinositol 3-kinase (PI3K) and the Ras/mitogen-activated protein kinase (MAPK) cascades are the signaling pathways mainly involved in the MM development. In the last decade, several molecules interfering with growth and survival promoting signaling have been developed.

EXPERT OPINION

Despite the availability of novel therapeutics, MM still evolves into a drug-resistant phase and most patients die of progressive disease. Therefore, there is an urgent need of novel therapeutic strategies. Among a plethora of new investigational agents, microRNA (miRNA) represents the basis for the design of novel therapeutic strategies which basically rely on miRNA inhibition or miRNA replacement approaches and take benefit respectively from the use of miRNA inhibitors or synthetic miRNAs as well as from lipid-based nanoparticles as carriers for in vivo delivery.

Macrophages in multiple myeloma: emerging concepts and therapeutic implications

Multiple myeloma, a clonal plasma cell malignancy, has long provided a prototypic model to study regulatory interactions between malignant cells and their microenvironment. Myeloma-associated macrophages have historically received limited scrutiny, but recent work points to central and non-redundant roles in myeloma niche homeostasis. The evidence supports a paradigm of complex, dynamic and often mutable interactions between macrophages and other cellular constituents of the niche. We and others have shown that macrophages support myeloma cell growth, viability and drug resistance through both contact-mediated and non-contact-mediated mechanisms. These tumor-beneficial roles have evolved in opposition to, or in parallel with, intrinsic pro-inflammatory and tumoricidal properties. Thus, simple blockade of protective "don't eat me" signals on the surface of myeloma cells leads to macrophage-mediated myeloma cell killing. Macrophages also enhance the tumor-supportive role of mesenchymal stem/stromal cells (MSCs) in the niche: importantly, this interaction is bidirectional, producing a distinct state of macrophage polarization that we termed "MSC-educated macrophages." The intriguing pattern of cross-talk between macrophages, MSCs and tumor cells highlights the myeloma niche as a dynamic multi-cellular structure. Targeted reprogramming of these interactions harbors significant untapped therapeutic potential, particularly in the setting of minimal residual disease, the main obstacle toward a cure.

Screening of multiple myeloma by polyclonal rabbit anti-human plasmacytoma cell immunoglobulin

Antibody-based immunotherapy has been effectively used for tumor treatment. However, to date, only a few tumor-associated antigens (TAAs) or therapeutic targets have been identified. Identification of more immunogenic antigens is essential for improvements in multiple myeloma (MM) diagnosis and therapy. In this study, we synthesized a polyclonal antibody (PAb) by immunizing rabbits with whole human plasmacytoma ARH-77 cells and identified MM-associated antigens, including enlonase, adipophilin, and HSP90s, among others, via proteomic technologies. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that 200 µg/mL PAb inhibits the proliferation of ARH-77 cells by over 50% within 48 h. Flow cytometric assay indicated that PAb treatment significantly increases the number of apoptotic cells compared with other treatments (52.1% vs. NS, 7.3% or control rabbit IgG, 9.9%). In vivo, PAb delayed tumor growth and prolonged the lifespan of mice. Terminal deoxynucleotidyl transferase dUTP nick end labeling assay showed that PAb also induces statistically significant changes in apoptosis compared with other treatments (P<0.05). We therefore conclude that PAb could be used for the effective screening and identification of TAA. PAb may have certain anti-tumor functions in vitro and in vivo. As such, its combination with proteomic technologies could be a promising approach for sieving TAA for the diagnosis and therapy of MM.

Impact of primary molecular cytogenetic abnormalities and risk of progression in smoldering multiple myeloma

We studied 351 patients with smoldering multiple myeloma (SMM) in whom the underlying primary molecular cytogenetic subtype could be determined based on cytoplasmic immunoglobulin fluorescent in situ hybridization studies. Hundred and fifty-four patients (43.9%) had trisomies, 127 (36.2%) had immunoglobulin heavy chain (IgH) translocations, 14 (4%) both trisomies and IgH translocations, 53 (15.1%) no abnormalities detected and 3 (0.9%) had monosomy13/del(13q) in the absence of any other abnormality. Among 127 patients with IgH translocations, 57 were t(11;14), 36 t(4;14), 11 musculoaponeurotic fibrosarcoma (MAF) translocations, and 23 other or unknown IgH translocation partner. Time to progression (TTP) to symptomatic multiple myeloma was significantly shorter in patients with the t(4;14) compared with patients with t(11;14), median 28 versus 55 months, respectively, P=0.025. The median TTP was 28 months with t(4;14) (high-risk), 34 months with trisomies alone (intermediate-risk), 55 months with t(11;14), MAF translocations, other/unknown IgH translocations, monosomy13/del(13q) without other abnormalities, and those with both trisomies and IgH translocations (standard-risk), and not reached in patients with no detectable abnormalities (low-risk), P=0.001. There was a trend to shorter TTP with deletion 17p (median TTP, 24 months). Overall survival from diagnosis of SMM was significantly inferior with t(4;14) compared with t(11;14), median 105 versus 147 months, respectively, P=0.036.

Evidences of early senescence in multiple myeloma bone marrow mesenchymal stromal cells

Background

In multiple myeloma, bone marrow mesenchymal stromal cells support myeloma cell growth. Previous studies have suggested that direct and indirect interactions between malignant cells and bone marrow mesenchymal stromal cells result in constitutive abnormalities in the bone marrow mesenchymal stromal cells.

Design and Methods

The aims of this study were to investigate the constitutive abnormalities in myeloma bone marrow mesenchymal stromal cells and to evaluate the impact of new treatments.

Results

We demonstrated that myeloma bone marrow mesenchymal stromal cells have an increased expression of senescence-associated β-galactosidase, increased cell size, reduced proliferation capacity and characteristic expression of senescence-associated secretory profile members. We also observed a reduction in osteoblastogenic capacity and immunomodulatory activity and an increase in hematopoietic support capacity. Finally, we determined that current treatments were able to partially reduce some abnormalities in secreted factors, proliferation and osteoblastogenesis.

Conclusions

We showed that myeloma bone marrow mesenchymal stromal cells have an early senescent profile with profound alterations in their characteristics. This senescent state most likely participates in disease progression and relapse by altering the tumor microenvironment.

Multiple myeloma: 2013 update on diagnosis, risk-stratification, and management

DISEASE OVERVIEW

Multiple myeloma accounts for approximately 10% of hematologic malignancies.

DIAGNOSIS

The diagnosis requires 10% or more clonal plasma cells on bone marrow examination or a biopsy proven plasmacytoma plus evidence of associated end-organ damage. In addition, the presence of 60% or more clonal plasma cells in the marrow is also considered as myeloma regardless of the presence or absence of end-organ damage.

RISK STRATIFICATION

In the absence of concurrent trisomies, patients with 17p deletion, t(14;16), and t(14;20) are considered to have high-risk myeloma. Patients with t(4;14) translocation are considered intermediate-risk. All others are considered as standard-risk. RISK-ADAPTED INITIAL THERAPY: Standard-risk patients can be treated with lenalidomide plus low-dose dexamethasone (Rd), or a bortezomib-containing triplet such as bortezomib, cyclophosphamide, dexamethasone (VCD). Intermediate-risk and high-risk patients require a bortezomib-based triplet regimen. In eligible patients, initial therapy is given for approximately 4 months followed by autologous stem cell transplantation (ASCT). Standard-risk patients can opt for delayed ASCT if stem cells can be cryopreserved. In patients are not candidates for transplant, initial therapy is given for approximately 12-18 months.

MAINTENANCE THERAPY

After initial therapy, lenalidomide maintenance is considered for standard-risk patients who are not in very good partial response or better, while maintenance with a bortezomib-based regimen should be considered in pateints with intermediate or high-risk myeloma.

MANAGEMENT OF REFRACTORY DISEASE

Patients with indolent relapse can be treated first with two-drug or three-drug combinations. Patients with more aggressive relapse often require therapy with a combination of multiple active agents.

Targeting miR-21 inhibits in vitro and in vivo multiple myeloma cell growth

PURPOSE

Deregulated expression of miRNAs plays a role in the pathogenesis and progression of multiple myeloma. Among upregulated miRNAs, miR-21 has oncogenic potential and therefore represents an attractive target for the treatment of multiple myeloma.

EXPERIMENTAL DESIGN

Here, we investigated the in vitro and in vivo anti-multiple myeloma activity of miR-21 inhibitors.

RESULTS

Either transient-enforced expression or lentivirus-based constitutive expression of miR-21 inhibitors triggered significant growth inhibition of primary patient multiple myeloma cells or interleukin-6-dependent/independent multiple myeloma cell lines and overcame the protective activity of human bone marrow stromal cells. Conversely, transfection of miR-21 mimics significantly increased proliferation of multiple myeloma cells, showing its tumor-promoting potential in multiple myeloma. Importantly, upregulation of miR-21 canonical validated targets (PTEN, Rho-B, and BTG2), together with functional impairment of both AKT and extracellular signal-regulated kinase signaling, were achieved by transfection of miR-21 inhibitors into multiple myeloma cells. In vivo delivery of miR-21 inhibitors in severe combined immunodeficient mice bearing human multiple myeloma xenografts expressing miR-21 induced significant antitumor activity. Upregulation of PTEN and downregulation of p-AKT were observed in retrieved xenografts following treatment with miR-21 inhibitors.

CONCLUSION

Our findings show the first evidence that in vivo antagonism of miR-21 exerts anti-multiple myeloma activity, providing the rationale for clinical development of miR-21 inhibitors in this still incurable disease.

Proton NMR-based metabolite analyses of archived serial paired serum and urine samples from myeloma patients at different stages of disease activity identifies acetylcarnitine as a novel marker of active disease

BACKGROUND

Biomarker identification is becoming increasingly important for the development of personalized or stratified therapies. Metabolomics yields biomarkers indicative of phenotype that can be used to characterize transitions between health and disease, disease progression and therapeutic responses. The desire to reproducibly detect ever greater numbers of metabolites at ever diminishing levels has naturally nurtured advances in best practice for sample procurement, storage and analysis. Reciprocally, since many of the available extensive clinical archives were established prior to the metabolomics era and were not processed in such an 'ideal' fashion, considerable scepticism has arisen as to their value for metabolomic analysis. Here we have challenged that paradigm.

METHODS

We performed proton nuclear magnetic resonance spectroscopy-based metabolomics on blood serum and urine samples from 32 patients representative of a total cohort of 1970 multiple myeloma patients entered into the United Kingdom Medical Research Council Myeloma IX trial.

FINDINGS

Using serial paired blood and urine samples we detected metabolite profiles that associated with diagnosis, post-treatment remission and disease progression. These studies identified carnitine and acetylcarnitine as novel potential biomarkers of active disease both at diagnosis and relapse and as a mediator of disease associated pathologies.

CONCLUSIONS

These findings show that samples conventionally processed and archived can provide useful metabolomic information that has important implications for understanding the biology of myeloma, discovering new therapies and identifying biomarkers potentially useful in deciding the choice and application of therapy.

B-cell maturation antigen is a promising target for adoptive T-cell therapy of multiple myeloma

PURPOSE

Multiple myeloma is a usually incurable malignancy of plasma cells. New therapies are urgently needed for multiple myeloma. Adoptive transfer of chimeric antigen receptor (CAR)-expressing T cells is a promising new therapy for hematologic malignancies, but an ideal target antigen for CAR-expressing T-cell therapies for multiple myeloma has not been identified. B-cell maturation antigen (BCMA) is a protein that has been reported to be selectively expressed by B-lineage cells including multiple myeloma cells. Our goal was to determine if BCMA is a suitable target for CAR-expressing T cells.

EXPERIMENTAL DESIGN

We conducted an assessment of BCMA expression in normal human tissues and multiple myeloma cells by flow cytometry, quantitative PCR, and immunohistochemistry. We designed and tested novel anti-BCMA CARs.

RESULTS

BCMA had a restricted RNA expression pattern. Except for expression in plasma cells, BCMA protein was not detected in normal human tissues. BCMA was not detected on primary human CD34(+) hematopoietic cells. We detected uniform BCMA cell-surface expression on primary multiple myeloma cells from five of five patients. We designed the first anti-BCMA CARs to be reported and we transduced T cells with lentiviral vectors encoding these CARs. The CARs gave T cells the ability to specifically recognize BCMA. The anti-BCMA-CAR-transduced T cells exhibited BCMA-specific functions including cytokine production, proliferation, cytotoxicity, and in vivo tumor eradication. Importantly, anti-BCMA-CAR-transduced T cells recognized and killed primary multiple myeloma cells.

CONCLUSIONS

BCMA is a suitable target for CAR-expressing T cells, and adoptive transfer of anti-BCMA-CAR-expressing T cells is a promising new strategy for treating multiple myeloma.

Doublets, triplets, or quadruplets of novel agents in newly diagnosed myeloma?

The treatment of multiple myeloma is evolving rapidly. A plethora of doublet, triplet, and quadruplet combinations have been studied for the treatment of newly diagnosed myeloma. Although randomized trials have been conducted comparing older regimens such as melphalan-prednisone with newer regimens containing drugs such as thalidomide, lenalidomide, or bortezomib, there are few if any randomized trials that have compared modern combinations with each other. Even in the few trials that have done so, definitive overall survival or patient-reported quality-of-life differences have not been demonstrated. Therefore, there is marked heterogeneity in how newly diagnosed patients with myeloma are treated around the world. The choice of initial therapy is often dictated by availability of drugs, age and comorbidities of the patient, and assessment of prognosis and disease aggressiveness. This chapter reviews the current data on the most commonly used and tested doublet, triplet, and quadruplet combinations for the treatment of newly diagnosed myeloma and provides guidance on choosing the optimal initial treatment regimen.

Anti-myeloma activity of Akt inhibition is linked to the activation status of PI3K/Akt and MEK/ERK pathway

The PI3K/Akt/mTOR signal transduction pathway plays a central role in multiple myeloma (MM) disease progression and development of therapeutic resistance. mTORC1 inhibitors have shown limited efficacy in the clinic, largely attributed to the reactivation of Akt due to rapamycin induced mTORC2 activity. Here, we present promising anti-myeloma activity of MK-2206, a novel allosteric pan-Akt inhibitor, in MM cell lines and patient cells. MK-2206 was able to induce cytotoxicity and inhibit proliferation in all MM cell lines tested, albeit with significant heterogeneity that was highly dependent on basal pAkt levels. MK-2206 was able to inhibit proliferation of MM cells even when cultured with marrow stromal cells or tumor promoting cytokines. The induction of cytotoxicity was due to apoptosis, which at least partially was mediated by caspases. MK-2206 inhibited pAkt and its down-stream targets and up-regulated pErk in MM cells. Using MK-2206 in combination with rapamycin (mTORC1 inhibitor), LY294002 (PI3K inhibitor), or U0126 (MEK1/2 inhibitor), we show that Erk- mediated downstream activation of PI3K/Akt pathway results in resistance to Akt inhibition. These provide the basis for clinical evaluation of MK-2206 alone or in combination in MM and potential use of baseline pAkt and pErk as biomarkers for patient selection.

Monoclonal gammopathy of renal significance: when MGUS is no longer undetermined or insignificant

Multiple myeloma is the most frequent monoclonal gammopathy to involve the kidney; however, a growing number of kidney diseases associated with other monoclonal gammopathies are being recognized. Although many histopathologic patterns exist, they are all distinguished by the monoclonal immunoglobulin (or component) deposits. The hematologic disorder in these patients is more consistent with monoclonal gammopathy of undetermined significance (MGUS) than with multiple myeloma. Unfortunately, due to the limitations of the current diagnostic schema, they are frequently diagnosed as MGUS. Because treatment is not recommended for MGUS, appropriate therapy is commonly withheld. In addition to end-stage renal disease, the persistence of the monoclonal gammopathy is associated with high rates of recurrence after kidney transplantation. Preservation and restoration of kidney function are possible with successful treatment targeting the responsible clone. Achievement of hematologic complete response has been shown to prevent recurrence after kidney transplantation. There is a need for a term that properly conveys the pathologic nature of these diseases. We think the term monoclonal gammopathy of renal significance is most helpful to indicate a causal relationship between the monoclonal gammopathy and the renal damage and because the significance of the monoclonal gammopathy is no longer undetermined.

Synthetic miR-34a mimics as a novel therapeutic agent for multiple myeloma: in vitro and in vivo evidence

PURPOSE

Deregulated expression of miRNAs has been shown in multiple myeloma (MM). A promising strategy to achieve a therapeutic effect by targeting the miRNA regulatory network is to enforce the expression of miRNAs that act as tumor suppressor genes, such as miR-34a.

EXPERIMENTAL DESIGN

Here, we investigated the therapeutic potential of synthetic miR-34a against human MM cells in vitro and in vivo.

RESULTS

Either transient expression of miR-34a synthetic mimics or lentivirus-based miR-34a-stable enforced expression triggered growth inhibition and apoptosis in MM cells in vitro. Synthetic miR-34a downregulated canonic targets BCL2, CDK6, and NOTCH1 at both the mRNA and protein level. Lentiviral vector-transduced MM xenografts with constitutive miR-34a expression showed high growth inhibition in severe combined immunodeficient (SCID) mice. The anti-MM activity of lipidic-formulated miR-34a was further shown in vivo in two different experimental settings: (i) SCID mice bearing nontransduced MM xenografts; and (ii) SCID-synth-hu mice implanted with synthetic 3-dimensional scaffolds reconstituted with human bone marrow stromal cells and then engrafted with human MM cells. Relevant tumor growth inhibition and survival improvement were observed in mice bearing TP53-mutated MM xenografts treated with miR-34a mimics in the absence of systemic toxicity.

CONCLUSIONS

Our findings provide a proof-of-principle that formulated synthetic miR-34a has therapeutic activity in preclinical models and support a framework for development of miR-34a-based treatment strategies in MM patients.

Identification of M protein from filter paper using serum protein and immunofixation electrophoresis

Serum protein electrophoresis (SPE) and immunofixation electrophoresis (IFE) are standard methods for detection and monitoring of monoclonal (M) proteins. However, these tests are rarely available in the remote areas, especially in developing countries. Transportation of fresh serum (FS) samples is also usually inconvenient. This study investigated M-protein identification using serum blot on filter paper (FP). SPE and IFE were performed on FS and FP specimens using the Sebia Hydrasys automated electrophoresis system. Statistical analyses were conducted to assess sample stability and agreement of FS vs FP. The FP method showed good agreement with the FS method. The r values for correlation of albumin levels-α(1), α(2), β, and γ (%)-between FP and FS samples in SPE were all more than 0.95 (P < .01). IFE displayed no significant difference between those 2 methods in the identification of M protein. The FP method demonstrated an accurate and reproducible alternative to FS for identification of M protein using SPE and IFE.

Antigen-specificity of oligoclonal abnormal protein bands in multiple myeloma after allogeneic stem cell transplantation

Myeloma patients may develop oligoclonal immunoglobulins, so-called abnormal protein bands (APB), after stem cell transplantation. APB do not correspond to the patient's paraprotein and confer a good prognosis. We set out to investigate whether such APB represent a humoral anti-myeloma immune response by screening immunoglobulins of 15 myeloma patients after allogeneic stem cell transplantation and a control group of healthy donors for reactivity with myeloma protein extracts. While the immunoglobulins of healthy donors did not react with myeloma protein extracts, patient-derived immunoglobulins showed variable levels of interaction, depending on the presence of APB on immunofixation. Most commonly, we detected interactions with heat-shock proteins, followed by neutral alpha-glucosidase, alpha-enolase and vimentin, as well as proliferating cell nuclear antigen and MAGEA4. More than 80% of targets were upregulated in myeloma. Heat-shock protein 60 (HSP60) was subsequently evaluated as an exemplary antigen. We found that HSP60 was aberrantly displayed on the surface of primary myeloma cells. Indeed, patient-derived APB-containing immunoglobulins recognized surface HSP60 suggesting that this antigen becomes accessible to the immune system after aberrant membrane exposition. We conclude that immunoglobulin fractions with APB recognize recurrent myeloma antigens and that this humoral response may contribute to the more favorable prognosis in patients with APB.

Impediments to curing myeloma in 2012

SUMMARY Our understanding of multiple myeloma biology over the last two decades has led to a marked improvement in progression-free and overall survival for the majority of patients. The introduction of novel agents, improvement in administration of high-dose therapy with autologous stem cell support, along with supportive care measures have enabled the myeloma researchers to once again debate the curability of this disease. The present article is a succinct review of the progress that has been made and the impediments to curability of this disease.

Dissociated responses to newer antimyeloma drugs identify a subset of refractory patients with an extremely poor prognosis

We describe the striking and unexpected evolution of 10 patients with de novo multiple myeloma treated with novel-agent based induction therapy, who displayed a dissociated evolution characterised by an apparent good response contrasting with the concomitant development of aggressive non-secreting plasmocytomas immediately before, or just after, autologous stem cell transplantation. Patients did not respond to salvage therapies. Eight of them died from progression less than 12 months after diagnosis. This unusual evolution in the era of novel agents warrants further scrutiny.

Fifty years of melphalan use in hematopoietic stem cell transplantation

Melphalan remains the most widely used agent in preparative regimens for hematopoietic stem cell transplantation (SCT). From its initial discovery more than 50 years ago, it has been gradually incorporated in the conditioning regimens for both autologous and allogeneic transplantations because of its myeloablative properties and broad antitumor effects as a DNA alkylating agent. Melphalan remains the mainstay conditioning for multiple myeloma and lymphomas, and it has been used successfully in preparative regimens of a variety of other hematological and nonhematological malignancies. The addition of newer agents to conditioning, such as bortezomib or lenalidomide for myeloma or clofarabine for myeloid malignancies, may improve antitumor effects for transplantation, whereas melphalan in combination with alemtuzumab may represent a backbone for future cellular therapy because of reliable engraftment and low toxicity profile. This review summarizes the development and the current use of this remarkable drug in hematopoietic SCT.