1p21 deletions are strongly associated with 1q21 gains and are an independent adverse prognostic factor for the outcome of high-dose chemotherapy in patients with multiple myeloma

Pathogenesis, clinical characteristics and personalized managements of multiple myeloma with chromosome 1 abnormalities

Multiple myeloma (MM) is a biologically heterogeneous malignancy defined by the proliferation of monoclonal plasma cells. Despite the tremendous advancement in MM treatment over the past decades, relapse remains a major problem which is inevitable for most patients. In particular, a partial of patients with early relapse and poor outcomes are classified as a high-risk group. Apart from the clinical stage, genetic aberrations are now recognized as important prognostic factors for identifying high-risk patients. Chromosome 1 abnormalities (C1As), particularly 1q21 gain or amplification, have been identified as common genetic aberrations in patients with MM and are often considered unfavorable prognostic markers for progression-free survival and overall survival. However, more effective therapeutic approaches are still needed to overcome the negative impact of C1As. Therefore, we summarize the prevalence, pathogenesis, clinical significance and present therapeutic condition of C1As in MM, and attempt to conclude the precise and personalized management for patients with C1As.

Genomics of Plasma Cell Leukemia

Simple Summary

Plasma cell leukemia (PCL) is a very aggressive plasma cell disorder with a dismal prognosis, despite the therapeutic progress made in the last few years. The implementation of genomic high-throughput technologies in the clinical setting has revealed new insights into the genomic landscape of PCL, some of which may have an impact on the development of novel therapeutic approaches. The purpose of this review is to provide a comprehensive overview and update of the genomic studies carried out in PCL.

Abstract

Plasma cell leukemia (PCL) is a rare and highly aggressive plasma cell dyscrasia characterized by the presence of clonal circulating plasma cells in peripheral blood. PCL accounts for approximately 2–4% of all multiple myeloma (MM) cases. PCL can be classified in primary PCL (pPCL) when it appears de novo and in secondary PCL (sPCL) when it arises from a pre-existing relapsed/refractory MM. Despite the improvement in treatment modalities, the prognosis remains very poor. There is growing evidence that pPCL is a different clinicopathological entity as compared to MM, although the mechanisms underlying its pathogenesis are not fully elucidated. The development of new high-throughput technologies, such as microarrays and new generation sequencing (NGS), has contributed to a better understanding of the peculiar biological and clinical features of this disease. Relevant information is now available on cytogenetic alterations, genetic variants, transcriptome, methylation patterns, and non-coding RNA profiles. Additionally, attempts have been made to integrate genomic alterations with gene expression data. However, given the low frequency of PCL, most of the genetic information comes from retrospective studies with a small number of patients, sometimes leading to inconsistent results.

Gene Expression Profiling in Multiple Myeloma: Redefining the Paradigm of Risk-Adapted Treatment

Multiple myeloma is a blood cancer characterized by clonal proliferation of plasma cells in the bone marrow. In recent years, several new drugs have been added to the therapeutic landscape of multiple myeloma, which have contributed to increased survival rates. However, while the use of therapeutics has evolved, there is still a group of high-risk patients who do not benefit from current treatment strategies. Risk stratification and risk-adapted treatment are crucial to identify the group of patients with urgent need for novel therapies. Gene expression profiling has been introduced as a tool for risk stratification in multiple myeloma based on the genetic make-up of myeloma cells. In this review we discuss the challenge of defining the high-risk multiple myeloma patient. We focus on the standardized analysis of myeloma cancer cells by gene expression profiling and describe how gene expression profiling provides additional insights for optimal risk-adapted treatment of patients suffering from multiple myeloma.

Current approaches to management of high-risk multiple myeloma

The median overall survival in multiple myeloma is rapidly approaching 10 years; however, in nearly a fifth of patients the prognosis remains poor. Therefore, the modern-day management of myeloma patients should be individualized, with a more intense and continuous approach in these high-risk patients. This includes first-line treatment based on multi-drug combinations employing the most effective drug combinations, upfront autologous stem cell transplantation (in eligible patients with tandem transplantation being a consideration), and maintenance based on proteasome inhibitor-based combinations. This paper reviews the results of recent retrospective analyses and clinical trials, but also gives a glance into the future by presenting the ongoing trials.

Bortezomib-based regimens improve the prognosis of newly diagnosed MM patients with chromosomal aberrations except for del(17q13): A retrospective study from a single center

Chromosomal aberrations are generally considered to have a remarkable impact on the outcome of multiple myeloma. Bortezomib helps to achieve complete responses and leads to longer life expectancy in many multiple myeloma patients. This study was designed to clarify whether bortezomib can improve the poor prognosis resulting from del(17q13), del(13q14), amp(1q21), t(4,14), t(14,16) in patients with multiple myeloma. A total of 255 MM patients treated with bortezomib-based regimens were included in this study. All chromosomal aberrations were detected by interphase fluorescence in situ hybridization. Kaplan-Meier survival and Multivariable Cox regression analysis were employed to assess the prognostic situation in progression-free survival and overall survival. The result showed that the progression-free survival and overall survival of patients with del(17q13) were shorter than those without del(17q13) in multivariate analysis and patients with del(13q14), amp(1q21), t(4,14), t(14,16) were similar to patients without these chromosomal aberrations in progression-free survival and overall survival after receiving bortezomib-based regimens.In conclusion Bortezomib-based regimens can overcome the poor prognosis derived from del(13q14), amp(1q21), t(4,14), t(14,16) but not del(17q13).

Chromosome 1q21 abnormalities in multiple myeloma

Gain of chromosome 1q (+1q) is one of the most common recurrent cytogenetic abnormalities in multiple myeloma (MM), occurring in approximately 40% of newly diagnosed cases. Although it is often considered a poor prognostic marker in MM, +1q has not been uniformly adopted as a high-risk cytogenetic abnormality in guidelines. Controversy exists regarding the importance of copy number, as well as whether +1q is itself a driver of poor outcomes or merely a common passenger genetic abnormality in biologically unstable disease. Although the identification of a clear pathogenic mechanism from +1q remains elusive, many genes at the 1q21 locus have been proposed to cause early progression and resistance to anti-myeloma therapy. The plethora of potential drivers suggests that +1q is not only a causative factor or poor outcomes in MM but may be targetable and/or predictive of response to novel therapies. This review will summarize our current understanding of the pathogenesis of +1q in plasma cell neoplasms, the impact of 1q copy number, identify potential genetic drivers of poor outcomes within this subset, and attempt to clarify its clinical significance and implications for the management of patients with multiple myeloma.

Multiple Myeloma: Heterogeneous in Every Way

Simple Summary

With the development of modern therapies in multiple myeloma, prognosis stratification is becoming an indispensable tool for the choice of treatment between patients. Many factors influence the prognosis in multiple myeloma; scores, mainly based on biochemical parameters and cytogenetics, have been proposed to discriminate patients. However, these scores are not perfect and fail to predict some patients’ outcomes. In this review, we describe current evaluated factors and their limitations. In the second part, we address factors with an impact on treatment escape and prognosis, but which are not available routinely yet.

Abstract

Multiple myeloma (MM) is a hematological malignancy characterized by the accumulation of tumor plasma cells (PCs) in the bone marrow (BM). Despite considerable advances in terms of treatment, patients’ prognosis is still very heterogeneous. Cytogenetics and minimal residual disease both have a major impact on prognosis. However, they do not explain all the heterogeneity seen in the outcomes. Their limitations are the result of the emergence of minor subclones missed at diagnosis, detected by sensible methods such as single-cell analysis, but also the non-exploration in the routine practice of the spatial heterogeneity between different clones according to the focal lesions. Moreover, biochemical parameters and cytogenetics do not reflect the whole complexity of MM. Gene expression is influenced by a tight collaboration between cytogenetic events and epigenetic regulation. The microenvironment also has an important impact on the development and the progression of the disease. Some of these determinants have been described as independent prognostic factors and could be used to more accurately predict patient prognosis and response to treatment.

The survival impact of CKS1B gains or amplification is dependent on the background karyotype and TP53 deletion status in patients with myeloma

Gains or amplification (amp) of chromosome 1q21/CKS1B are reported to be a high-risk factor in myeloma. In this retrospective study, we analyzed the impact of CKS1B gain/amp on overall survival in the context of other genetic aberrations, such as TP53 deletion, FGFR3-IGH, IGH-MAF, MYEOV/CCND1-IGH, and RB1, as well as karyotype. The cohort included 132 myeloma patients with CKS1B gain/amp detected by fluorescence in-situ hybridization. There were 72 men and 60 women with a median age of 65 years (range 39-88 years). A normal, simple, or complex karyotype was observed in 39.5%, 5.4%, and 55% of patients, respectively. "Double hit," defined as CKS1B gain/amp coexisting with TP53 deletion, or "triple hit," defined as double hit plus t(4;14)FGFR3-IGH or t(14;16)IGH-MAF, were identified in 25 patients (18.9%) and five patients (3.8%), respectively. Double and triple hit were highly associated with a complex karyotype (p = 0.02). Ninety-nine patients (99/128, 77.3%) received stem cell transplantation. The median follow-up time was 48.2 months (range 2-104 months); 68 patients (51.5%) died, with a median overall survival of 58.8 months. Multivariate analysis (Cox model) showed that double hit with TP53 deletion (p = 0.0031), triple hit (p = 0.01), and complex karyotype (p = 0.0009) were each independently associated with poorer overall survival. Stem cell transplantation was associated with better overall survival, mainly in patients with a double or triple hit and complex karyotype (p = 0.003). These findings indicate that the inferior outcome of myeloma patients with CKS1B gain/amp is attributable to the high number of high-risk patients in this group. The prognostic impact of CKS1B gain/amp depends on the background karyotype and TP53 status.

Protein tyrosine phosphatases in multiple myeloma

Many cell signaling pathways are activated or deactivated by protein tyrosine phosphorylation and dephosphorylation, catalyzed by protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs), respectively. Even though PTPs are as important as PTKs in this process, their role has been neglected for a long time. Multiple myeloma (MM) is a cancer of plasma cells, which is characterized by production of monoclonal immunoglobulin, anemia and destruction of bone. MM is still incurable with high relapse frequency after treatment. In this review, we highlight the PTPs that were previously described in MM or have a role that can be relevant in a myeloma context. Our purpose is to show that despite the importance of PTPs in MM pathogenesis, many unanswered questions in this field need to be addressed. This might help to detect novel treatment strategies for MM patients.

Expert Panel Consensus Statement for Proper Evaluation of First Relapse in Multiple Myeloma

PURPOSE OF REVIEW

A working group of six expert physicians convened to assess the spectrum of multiple myeloma relapse presentations, discussed the features that can define the disease as aggressive and not aggressive, and established whether this information could help in selecting treatment together with the characteristics of disease and of patients and type of prior therapy.

RECENT FINDINGS

The working group agreed that relapse should be distinguished between biochemical and clinical according to IMWG. Moreover, the expert panel defined "aggressive disease" as a clinical condition that requires therapy able to induce a rapid and as deep as possible response to release symptoms and to avoid impending danger of new events. According to this definition, relapse was considered aggressive if it presents with at least one of the following features: doubling of M protein rate over 2 months, renal insufficiency, hypercalcemia, extramedullary disease, elevated LDH, high plasma cell proliferative index, presence of plasma cells in peripheral blood, or skeletal-related complications. Moreover, the panel agreed that this classification can be useful to choose therapy in first relapse together with other patient, disease, and prior therapy characteristics. So, this item was included in a new therapeutic algorithm. The treatment choice in MM at relapse is wider than in the past with the availability of many new therapeutic regimens leading to increased diversity of approaches and relevant risk of inappropriate treatment decisions. A practical classification of relapses into aggressive or non-aggressive, included in a decisional algorithm on MM management at first relapse, could help to make the appropriate treatment decisions.

Gain of Chromosome 1q is associated with early progression in multiple myeloma patients treated with lenalidomide, bortezomib, and dexamethasone

Gain of chromosome 1q (+1q) is commonly identified in multiple myeloma and has been associated with inferior outcomes. However, the prognostic implication of +1q has not been evaluated in the setting of standard triplet regimens. We retrospectively analyzed 201 consecutive patients with newly diagnosed myeloma who received induction with lenalidomide, bortezomib, and dexamethasone (RVD) and were tested for +1q at diagnosis by fluorescent in-situ hybridization. Patients with +1q (n = 94), compared to those without +1q (n = 107), had shorter median progression-free survival (PFS) (41.9 months vs 65.1 months, p = 0.002, HR = 1.90) and overall survival (median not reached (NR) for either arm, p = 0.003, HR 2.69). In subgroup analyses, patients with co-occurring +1q and t(4;14), t(14;16) or del(17p) or with 4 or more copies of 1q had significantly worse PFS (25.1 months and 34.6 months, p < 0.001 and p = 0.0063, respectively), whereas patients with three copies and no other high-risk cytogenetic abnormalities had no significant difference in PFS. These data suggest that when treated with RVD induction, patients with +1q should be considered at very high risk for early progression in multiple myeloma when ≥4 copies are detected or in the context of other high-risk cytogenetic abnormalities.

IL6R-STAT3-ADAR1 (P150) interplay promotes oncogenicity in multiple myeloma with 1q21 amplification

1q21 amplification is an important prognostic marker in multiple myeloma. In this study we identified that IL6R (the interleukin-6 membrane receptor) and ADAR1 (an RNA editing enzyme) are critical genes located within the minimally amplified 1q21 region. Loss of individual genes caused suppression to the oncogenic phenotypes, the magnitude of which was enhanced when both genes were concomitantly lost. Mechanistically, IL6R and ADAR1 collaborated to induce a hyper-activation of the oncogenic STAT3 pathway. High IL6R confers hypersensitivity to interleukin-6 binding, whereas, ADAR1 forms a constitutive feed-forward loop with STAT3 in a P150-isoform-predominant manner. In this respect, ADAR1-P150 acts as a direct transcriptional target for STAT3 and this STAT3-induced-P150 in turn directly interacts with and stabilizes the former protein, leading to a larger pool of proteins acting as oncogenic transcription factors for pro-survival genes. The importance of both IL6R and ADAR1-P150 in STAT3 signaling was further validated when concomitant knockdown of both genes impeded IL6-induced-STAT3 pathway activation. Clinical evaluation of various datasets of myeloma patients showed that low expression of either one or both genes was closely associated with a compromised STAT3 signature, confirming the involvement of IL6R and ADAR1 in the STAT3 pathway and underscoring their essential role in disease pathogenesis. In summary, our findings highlight the complexity of the STAT3 pathway in myeloma, in association with 1q21 amplification. This study therefore reveals a novel perspective on 1q21 abnormalities in myeloma and a potential therapeutic target for this cohort of high-risk patients.

[Effect of 1q21 amplification on bortezomib therapeutic response and prognosis of newly diagnosed multiple myeloma patients]

Objective: To investigate the effect of 1q21 amplification (1q) on the therapeutic response and prognosis of bortezomib(Btz) in the treatment of newly diagnosed multiple myeloma (MM) patients. Methods: A total of 180 newly diagnosed MM were included for analyses of clinical characteristics, cytogenetics, objective response rate (ORR), progression-free survival (PFS) and overall survival (OS), retrospectively. Gene expression profiling (GEP) was analyzed using publicly available R2 platform. Results: ① In 180 patients, 1q was found in 51.1% cases. Of them, 174 patients had complete follow-up data, including 88 cases with 1q and 86 without 1q (non-1q). ②Incidence of 1q was positively associated with percentage of IGH rearrangement (72.2%, P=0.017) and 1p deletion (1p) (27.8%, P=0.040). ③ The median PFS was 15.0 and 20.3 months for the 1q group and non-1q group, and the median OS was 29.4 and 44.0 months, respectively. Both PFS and OS of 1q group was significantly shorter than those of the non-1q group (P=0.029 and 0.038, respectively). Multivariate analysis further revealed that 1q was an independent prognostic factor for both PFS (HR=1.910, 95% CI 1.105-3.303, P=0.020) and OS (HR=2.353, 95% CI 1.090-5.078, P=0.029). ④ In 91 evaluable cases with 1q, very good partial remission (VGPR) rate was higher after treatment with Btz than those without Btz (62.1% vs 40.0%, P=0.032). Of note, the patients with 1q who received auto-HSCT after induction with Btz had significantly longer PFS than those without auto-HSCT (19 months vs 13 months, P=0.048). ⑤GEP analysis revealed that 1q21 amplification predominantly up-regulated expression of >50% genes within 1q21 region, and also altered expression of 28% genes in chromosome 1 and 10% genes in whole genome, particularly related to DNA repair and cell cycle. Conclusions: 1q is an independent adverse prognostic factor in patients with newly diagnosed MM. It is often associated with 1p deletion and IGH rearrangement. Patients with 1q respond well to Btz-based regimen, but they fail to gain long-term benefit from this treatment itself. However, auto-HSCT following Btz induction might improve survival of patients with 1q, suggesting a potential strategy to treat this high-risk subset of MM. GEP analysis warrants further attention in understanding the mechanisms underlying the high-risk of 1q.

High serum lactate dehydrogenase predicts an unfavorable outcome in Chinese elderly patients with multiple myeloma

There is significant heterogeneity among multiple myeloma (MM) patients with the survival duration varying greatly from a few months to several years. This study retrospectively analyzed serum lactate dehydrogenase (LDH) in 105 cases of newly diagnosed elderly MM patients to investigate its value for outcome prediction. Serum LDH concentrations were evaluated prior to induction therapy. Prognostic analyses were carried out based on LDH levels and patients' other clinical data. We also applied the recently proposed Revised International Staging System (R-ISS) to 70 patients with the available data. Of all the patients, elevated serum LDH levels (≥271U/L) were observed in 13.3% (14 out of 105) patients at diagnosis. Compared with normal LDH group, high LDH group had significantly shorter overall survival (OS) (15.5 vs. 52.5 months, p = 0.002) and median progression free survival (PFS) (12.0 vs. 24 months, p = 0.030), as well as 2-year OS rate (20% vs. 81%, p < 0.001) and PFS rate (22% vs. 44%, p = 0.005). A multivariate analysis identified high LDH as a unique independent adverse prognostic parameter for both OS and PFS. In addition, there were significant differences between R-ISS II and R-ISS III patients in both median OS (52.5 vs. 15.5 months, p < 0.001) and PFS (23 vs. 7.5 months, p = 0.004). Furthermore, high LDH was a unique independent adverse indicator for overall response rate (ORR) and early death in elderly MM patients. These results identified LDH as an unfavorable prediction for the outcome of Chinese elderly patients with MM. R-ISS based on LDH is superior to ISS in prognostic assessment.

Aberrant lncRNA Expression in Multiple Myeloma

Multiple myeloma (MM), a type of malignant tumor, is characterized by dysplasia of clonal plasma cells in the bone marrow. People with MM will have damaged organs or tissues due to secretion of large amounts of monoclonal immunoglobulin or fragments (M protein). Despite improved survivability by novel treatment strategies over the last decade, MM is still incurable by current therapies. Long noncoding RNAs (lncRNAs), with length of more than 200 nucleotides, have been reported to act as important regulators in many diseases, including MM. Recent studies have reported aberrant lncRNA expression in MM; these dysregulated lncRNAs can play oncogenic and/or tumor-suppressive roles in the development and progression of MM. In this article, we present a general overview on the role of lncRNAs in MM pathogenesis and discuss their potential as prognostic biomarkers and targets for treatment.

Therapy for Relapsed Multiple Myeloma: Guidelines From the Mayo Stratification for Myeloma and Risk-Adapted Therapy

Life expectancy in patients with multiple myeloma is increasing because of the availability of an increasing number of novel agents with various mechanisms of action against the disease. However, the disease remains incurable in most patients because of the emergence of resistant clones, leading to repeated relapses of the disease. In 2015, 5 novel agents were approved for therapy for relapsed multiple myeloma. This surfeit of novel agents renders management of relapsed multiple myeloma more complex because of the occurrence of multiple relapses, the risk of cumulative and emergent toxicity from previous therapies, as well as evolution of the disease during therapy. A group of physicians at Mayo Clinic with expertise in the care of patients with multiple myeloma regularly evaluates the evolving literature on the biology and therapy for multiple myeloma and issues guidelines on the optimal care of patients with this disease. In this article, the latest recommendations on the diagnostic evaluation of relapsed multiple myeloma and decision trees on how to treat patients at various stages of their relapse (off study) are provided together with the evidence to support them.

Epigenetic silencing of miR-137 induces drug resistance and chromosomal instability by targeting AURKA in multiple myeloma

Multiple myeloma (MM) is the second most prevalent hematologic malignancy. Aberrant microRNAs (miRNAs) expression has been shown to be involved in the pathogenesis of MM. In this study, we further demonstrated that miR-137 was significantly downregulated in MM and negatively correlated with clinical prognosis. Moreover, we described the epigenetic regulation of miR-137 and its association with progression-free survival in MM patients. Furthermore, overexpression of miR-137 in MM cell line (miR-137 OE) increased its sensitivity to bortezomib and eprirubicin in vitro. Also, some high-risk genetic abnormalities in MM, including deletion of chromosome 1p22.2, 14q or 17p13, and gain of chromosome 1p22.2 were detected in NCI-H929 empty vector (NCI-H929 EV) treated cells but not in the NCI-H929 miR-137 overexpression (NCI-H929 miR-137 OE) cells. Luciferase reporter assays demonstrated that miR-137 targeted AURKA. Ectopic expression of miR-137 strongly reduced the expression of AURKA and p-ATM/Chk2 in MM cells, and increased the expression of p53, and p21. Importantly, miR-137 overexpression together with bortezomib treatment significantly inhibited tumor growth in MM xenograft model. Taken together, this study demonstrates that miR-137 is epigenetically silenced in MM, and overexpression of miR-137 could reduce drug resistance and overcome chromosomal instability of the MM cells via affecting the apoptosis and DNA damage pathways.

Treatment of multiple myeloma with high-risk cytogenetics: a consensus of the International Myeloma Working Group

The International Myeloma Working Group consensus updates the definition for high-risk (HR) multiple myeloma based on cytogenetics Several cytogenetic abnormalities such as t(4;14), del(17/17p), t(14;16), t(14;20), nonhyperdiploidy, and gain(1q) were identified that confer poor prognosis. The prognosis of patients showing these abnormalities may vary with the choice of therapy. Treatment strategies have shown promise for HR cytogenetic diseases, such as proteasome inhibition in combination with lenalidomide/pomalidomide, double autologous stem cell transplant plus bortezomib, or combination of immunotherapy with lenalidomide or pomalidomide. Careful analysis of cytogenetic subgroups in trials comparing different treatments remains an important goal. Cross-trial comparisons may provide insight into the effect of new drugs in patients with cytogenetic abnormalities. However, to achieve this, consensus on definitions of analytical techniques, proportion of abnormal cells, and treatment regimens is needed. Based on data available today, bortezomib and carfilzomib treatment appear to improve complete response, progression-free survival, and overall survival in t(4;14) and del(17/17p), whereas lenalidomide may be associated with improved progression-free survival in t(4;14) and del(17/17p). Patients with multiple adverse cytogenetic abnormalities do not benefit from these agents. FISH data are implemented in the revised International Staging System for risk stratification.

Genomic Aberrations in Multiple Myeloma

Multiple myeloma (MM) is a genetically complex disease. The past few years have seen an evolution in cancer research with the emergence of next-generation sequencing (NGS), enabling high throughput sequencing of tumors-including whole exome, whole genome, RNA, and single-cell sequencing as well as genome-wide association study (GWAS). A few inherited variants have been described, counting for some cases of familial disease. Hierarchically, primary events in MM can be divided into hyperdiploid (HDR) and nonhyperdiploid subtypes. HRD tumors are characterized by trisomy of chromosomes 3, 5, 7, 9, 11, 15, 19, and/or 21. Non-HRD tumors harbor IGH translocations, mainly t(4;14), t(6;14), t(11;14), t(14;16), and t(14;20). Secondary events participate to the tumor progression and consist in secondary translocation involving MYC, copy number variations (CNV) and somatic mutations (such as mutations in KRAS, NRAS, BRAF, P53). Moreover, the dissection of clonal heterogeneity helps to understand the evolution of the disease. The following review provides a comprehensive review of the genomic landscape in MM.

Hematopoietic Stem Cell Transplantation for Multiple Myeloma: Guidelines from the American Society for Blood and Marrow Transplantation

Therapeutic strategies for multiple myeloma (MM) have changed dramatically over the past decade. Thus, the role of hematopoietic stem cell transplantation (HCT) must be considered in the context of this evolution. In this evidence-based review, we have critically analyzed the data from the most recent clinical trials to better understand how to incorporate HCT and when HCT is indicated. We have provided our recommendations based on strength of evidence with the knowledge that ongoing clinical trials make this a dynamic field. Within this document, we discuss the decision to proceed with autologous HCT, factors to consider before proceeding to HCT, the role of tandem autologous HCT, post-HCT maintenance therapy, and the role of allogeneic HCT for patients with MM.

miR-137 and miR-197 Induce Apoptosis and Suppress Tumorigenicity by Targeting MCL-1 in Multiple Myeloma

PURPOSE

Deregulation of miRNA has been implicated in the pathogenesis of multiple myeloma. We identified miR-137 and miR-197, mapped to the chromosome 1p (12)-(21) deletion region, and examined their antimyeloma activity as tumor suppressors.

EXPERIMENTAL DESIGN

The expression of miR-137/197 was examined in multiple myeloma and normal plasma cells by qRT-PCR. Functional effect of miR-137/197 was analyzed by cell viability, apoptosis, clonogenic, and migration assays. Antimyeloma activity of miR-137/197 was further evaluated in vivo by lentiviral-based or lipid-based delivery in a mouse xenograft model of multiple myeloma.

RESULTS

miR-137/197 expression was significantly lower in multiple myeloma cell lines and multiple myeloma patient samples compared with normal plasma cells. Transfection of miR-137/197 resulted in reduction of MCL-1 protein expression, as well as alteration of apoptosis-related genes, and induction of apoptosis, inhibition of viability, colony formation, and migration in multiple myeloma cells. MCL-1 was further validated as a direct target of miR-137/197. Conversely, overexpression of MCL-1 partially reverted the effect of miR-137/197. Importantly, in vivo lentiviral-mediated or intratumor delivery of miR-137/197 induced regression of tumors in murine xenograft models of multiple myeloma.

CONCLUSIONS

Our study reveals a novel role of miR-137/197 as tumor suppressors in mediating apoptosis in multiple myeloma cells by targeting MCL-1. Our findings provide a proof-of-principle that lentivirus-based or formulated synthetic miR-137/197 exerts therapeutic activity in preclinical models, and support a framework for development of miR-137/197-based treatment strategies in patients with multiple myeloma.

The impact of clone size on the prognostic value of chromosome aberrations by fluorescence in situ hybridization in multiple myeloma

PURPOSE

Accumulating evidence indicates that intratumor heterogeneity is prevalent in multiple myeloma and that a collection of multiple, genetically distinct subclones are present within the myeloma cell population. It is not clear whether the size of clonal myeloma populations harboring unique cytogenetic abnormalities carry any additional prognostic value.

EXPERIMENTAL DESIGN

We analyzed the prognostic impact of cytogenetic aberrations by fluorescence in situ hybridization at different cutoff values in a cohort of 333 patients with newly diagnosed myeloma and 92 patients with relapsed myeloma.

RESULTS

We found that nearly all IgH-related arrangements were observed in a large majority of the purified plasma cells; however, 13q deletion, 17p deletion, and 1q21 amplification appeared in different percentages within the malignant plasma cell population. Based on the size of subclones carrying these cytogenetic aberrations, the patients were divided into four groups: 0%-10%, 10.5%-20%, 20.5%-50%, and >50%. Receiver-operating characteristics analysis was applied to determine the optimal cutoff value with the greatest differential survival and showed that the most powerful clone sizes were 10% for 13q deletion, 50% for 17p deletion, and 20% for 1q21 gains, which provided the best possible cutoffs for predicting poor outcomes.

CONCLUSIONS

Our study indicated that the impact of clone size on prognostic value varies between specific genetic abnormalities. Prognostic value was observed for even a subgroup of plasma cells harboring the cytogenetic aberration of 13q deletion and 1q21 gains; however, 17p deletion displayed the most powerful cutoff for predicting survival only if the predominant clones harbored the abnormality.

Amplification of 1q21 and other abnormalities in multiple myeloma patients from a tertiary hospital in singapore

Much effort has been made to stratify multiple myeloma patients for targeted therapy. However, responses have been varied and improved patient stratifications are needed. Forty-five diagnostic samples from multiple myeloma patients (median age 65 years) were stratified cytogenetically as 15 having non-hyperdiploidy, 20 having hyperdiploidy and 10 having a normal karyotype. Fluorescence in situ hybridization (FISH) assays with FGFR3/IGH, CCND1/IGH, IGH/MAF, RB1 and TP53 probes on bone marrow samples showed that IGH rearrangements were the most common abnormality in the non-hyperdiploid group but these were also found among hyperdiploid patients and patients with normal cytogenetics. Of these, FGFR3/IGH rearrangements were most frequent. Deletion of RB1/monosomy 13 was the most common genetic abnormality across the three groups and was significantly higher among non-hyperdiploid compared to hyperdiploid patients. On the other hand, the study recorded a low incidence of TP53 deletion/monosomy 17. The FGFR3/IGH fusion was frequently seen with RB1 deletion/monosomy 13. FISH with 1p36/1q21 and 6q21/15q22 probes showed that amplification of 15q22 was seen in all of the hyperdiploid patients while amplification of 1q21, Amp(1q21), characterized non-hyperdiploid patients. In contrast, deletions of 1p36 and 6q21 were very rare events. Amp(1q21), FGFR3/IGH fusion, RB1 deletion/monosomy 13, and even TP53 deletion/monosomy 17 were seen in some hyperdiploid patients, suggesting that they have a less than favorable prognosis and require closer monitoring.

The RAG Model: A New Paradigm for Genetic Risk Stratification in Multiple Myeloma

Molecular studies have shown that multiple myeloma is a highly genetically heterogonous disease which may manifest itself as any number of diverse subtypes each with variable clinicopathological features and outcomes. Given this genetic heterogeneity, a universal approach to treatment of myeloma is unlikely to be successful for all patients and instead we should strive for the goal of personalised therapy using rationally informed targeted strategies. Current DNA sequencing technologies allow for whole genome and exome analysis of patient myeloma samples that yield vast amounts of genetic data and provide a mutational overview of the disease. However, the clinical utility of this information currently lags far behind the sequencing technology which is increasingly being incorporated into clinical practice. This paper attempts to address this shortcoming by proposing a novel genetically based “traffic-light” risk stratification system for myeloma, termed the RAG (Red, Amber, Green) model, which represents a simplified concept of how complex genetic data may be compressed into an aggregate risk score. The model aims to incorporate all known clinically important trisomies, translocations, and mutations in myeloma and utilise these to produce a score between 1.0 and 3.0 that can be incorporated into diagnostic, prognostic, and treatment algorithms for the patient.

Controversies in multiple myeloma: to transplant or not?

The treatment of multiple myeloma (MM) has dramatically changed in the last decade due to the introduction of the immunomodulatory drugs (IMIDs) and proteasome inhibitors, otherwise known as the novel agents. Prior to the advent of the novel agents, the gold standard of treatment had been high-dose chemotherapy with autologous stem cell transplantation (HDT/ASCT) for eligible candidates. Given the remarkable activity of the novel agents, and the significant morbidity of HDT/ASCT, the role of stem cell transplantation has now come into question. In this review, we explore the benefits and drawbacks to HDT/ASCT in the era of the novel therapies.

A gene expression based predictor for high risk myeloma treated with intensive therapy and autologous stem cell rescue

Myeloma is characterized by a highly variable clinical outcome. Despite the effectiveness of high-dose therapy, 15% of patients relapse within 1 year. We show that these cases also have a significantly shorter post-relapse survival compared to the others (median 14.9 months vs. 40 months, p = 8.03 × 10^{− 14}). There are no effective approaches to define this potentially distinct biological group such that treatment could be altered. In this work a series of uniformly treated patients with myeloma were used to develop a gene expression profiling (GEP)-based signature to identify this high risk clinical behavior. Gene enrichment analyses applied to the top differentially expressed genes showed a significant enrichment of epigenetic regulators as well as “stem cell” myeloma genes. A derived 17-gene signature effectively identifies patients at high risk of early relapse as well as impaired overall survival. Integrative genomic analyses showed that epigenetic mechanisms may play an important role on transcription of these genes.

Diagnosis and risk stratification in multiple myeloma

Multiple myeloma (MM) is a tumor of monoclonal plasma cells, which produce a monoclonal antibody and expand predominantly in the bone marrow. Patients present with hypercalcemia, renal impairment, anemia, and/or bone disease. Only patients with symptomatic MM require therapy, whereas asymptomatic patients receive regular follow-up. Survival of patients with MM is very heterogeneous. The variety in outcome is explained by host factors as well as tumor-related characteristics reflecting biology of the MM clone and tumor burden. The identification of cytogenetic abnormalities by fluorescence in situ hybridization is currently the most important and widely available prognostic factor in MM.

Chromosome 1 abnormalities in elderly patients with newly diagnosed multiple myeloma treated with novel therapies

Multiple myeloma is a plasma cell disorder characterized by malignant plasma cell infiltration in the bone marrow, serum and/or urine monoclonal protein and organ damage. The aim of this study was to investigate the impact of chromosome 1 abnormalities in a group of elderly patients (>65 years) with newly diagnosed multiple myeloma enrolled in the GIMEMA-MM-03-05 trial and treated with bortezomib, melphalan and prednisone or bortezomib, melphalan, prednisone and thalidomide followed by bortezomib and thalidomide maintenance. We also evaluated the link between chromosome 1 abnormalities and other clinical, genetic and immunophenotypic features by a multivariate logistic regression model. Interphase fluorescence in situ hybridization on immunomagnetically purified plasma cells and bone marrow multiparameter flow cytometry were employed. A multivariate Cox model showed that chromosome 1 abnormalities, age >75 years and a CD19(+)/CD117(-) immunophenotype of bone marrow plasma cells were independent risk factors for overall survival in elderly patients with newly diagnosed multiple myeloma. Moreover, a detrimental effect of thalidomide, even when administered in association with bortezomib, was observed in patients with abnormal chromosome 1 as well as in those with 17p deletion, while the benefit of adding thalidomide to the bortezomib-melphalan-prednisone regimen was noted in patients carrying an aggressive CD19(+)/CD117(-) bone marrow plasma cell immunophenotype. This trial was registered at www.clinicaltri-als.gov as #NCT01063179.

Quantitative analysis of CKS1B mRNA expression and copy number gain in patients with plasma cell disorders

In this study, we have examined CKS1B gene expression and copy number in a total of 114- patients at diagnosis: 83 with multiple myeloma (MM) and 31 with monoclonal gammopathy of undetermined significance (MGUS). Results were correlated with cytogenetics, FISH and clinical characteristic. Significant CKS1B mRNA levels in MM compared to MGUS cases (p<0.048) were detected. In MM, the frequency of 1q21 (CKS1B) copy gain was significantly higher in cases with abnormal karyotype compared to patients with normal karyotype (p=0.021). Global analysis showed a positive correlation between CKS1B expression and 1q21 copy number (p<0.0001). No association between CKS1B mRNA expression and clinical parameters was found. However, a significantly higher level of β2 microglobulin in cases with 1q21 gains than those without (p=0.0094) was observed. Overall survival was shorter in cases with 1q21 gain compared to those with normal 1q21 region (p=0.0082). Our results suggest a role for CKS1B in the multiple step process of progression of MGUS to MM and show that CKS1B copy gain has a more significant prognostic value than its overexpression. This adverse impact on survival probably reflects the genetic instability associated to chromosome 1q alterations resulting in a more aggressive behavior of the disease.

Neoplastic plasma cell aberrant antigen expression patterns and their association with genetic abnormalities

Little is known about aberrant antigen expression patterns and their association with cytogenetic aberrations in multiple myeloma (MM). We examined the correlation between flow cytometry and florescence in situ hybridization (FISH) in 167 marrow specimens with MM. Gene expression profiling of CD56, CD117, CD52 and CD20 mRNA in plasma cells (PCs) from patients treated on Total Therapy 2 and Total Therapy 3 trials were also evaluated. Higher expression of CD56 and CD117 was associated with hyperdiploidy. High CD52 mRNA expression was associated with c-MAF and FGFR3 subgroups. Higher expression of CD56 mRNA, but lower Kit expression, were noted in association with FGFR3. In contrast, the c-MAF subgroup showed high Kit expression but lacked NCAM mRNA expression. CKS1B amplification showed positive correlation with CD52 (p=0.0065) but negative correlation with CD20 (p=0.0207). These findings indicate that phenotypic differences in MM are associated with distinct genetic subgroups, which potentially has important diagnostic and prognostic value.

Genome-wide screening of cytogenetic abnormalities in multiple myeloma patients using array-CGH technique: a Czech multicenter experience

Characteristic recurrent copy number aberrations (CNAs) play a key role in multiple myeloma (MM) pathogenesis and have important prognostic significance for MM patients. Array-based comparative genomic hybridization (aCGH) provides a powerful tool for genome-wide classification of CNAs and thus should be implemented into MM routine diagnostics. We demonstrate the possibility of effective utilization of oligonucleotide-based aCGH in 91 MM patients. Chromosomal aberrations associated with effect on the prognosis of MM were initially evaluated by I-FISH and were found in 93.4% (85/91). Incidence of hyperdiploidy was 49.5% (45/91); del(13)(q14) was detected in 57.1% (52/91); gain(1)(q21) occurred in 58.2% (53/91); del(17)(p13) was observed in 15.4% (14/91); and t(4;14)(p16;q32) was found in 18.6% (16/86). Genome-wide screening using Agilent 44K aCGH microarrays revealed copy number alterations in 100% (91/91). Most common deletions were found at 13q (58.9%), 1p (39.6%), and 8p (31.1%), whereas gain of whole 1q was the most often duplicated region (50.6%). Furthermore, frequent homozygous deletions of genes playing important role in myeloma biology such as TRAF3, BIRC1/BIRC2, RB1, or CDKN2C were observed. Taken together, we demonstrated the utilization of aCGH technique in clinical diagnostics as powerful tool for identification of unbalanced genomic abnormalities with prognostic significance for MM patients.

The genetic architecture of multiple myeloma

Multiple myeloma is a malignant proliferation of monoclonal plasma cells leading to clinical features that include hypercalcaemia, renal dysfunction, anaemia, and bone disease (frequently referred to by the acronym CRAB) which represent evidence of end organ failure. Recent evidence has revealed myeloma to be a highly heterogeneous disease composed of multiple molecularly-defined subtypes each with varying clinicopathological features and disease outcomes. The major division within myeloma is between hyperdiploid and nonhyperdiploid subtypes. In this division, hyperdiploid myeloma is characterised by trisomies of certain odd numbered chromosomes, namely, 3, 5, 7, 9, 11, 15, 19, and 21 whereas nonhyperdiploid myeloma is characterised by translocations of the immunoglobulin heavy chain alleles at chromosome 14q32 with various partner chromosomes, the most important of which being 4, 6, 11, 16, and 20. Hyperdiploid and nonhyperdiploid changes appear to represent early or even initiating mutagenic events that are subsequently followed by secondary aberrations including copy number abnormalities, additional translocations, mutations, and epigenetic modifications which lead to plasma cell immortalisation and disease progression. The following review provides a comprehensive coverage of the genetic and epigenetic events contributing to the initiation and progression of multiple myeloma and where possible these abnormalities have been linked to disease prognosis.

Prognostic value of 1p deletion for multiple myeloma: a meta-analysis

INTRODUCTION

Previous studies have indicated that a deletion on the short arm of chromosome 1 negatively predicts survival in patients with multiple myeloma (MM). Due to the small sample size in each study, we performed this meta-analysis to comprehensively investigate the association between the 1p deletion and survival in patients with MM.

METHODS

A literature search was conducted in both foreign and Chinese databases, including SinoMed, CNKI, Wanfang, PubMed, EMBASE, and Scopus. Hazard ratios (HR) with 95% confidence intervals (CI) for overall survival (OS) and progression-free survival (PFS) in 11 eligible articles were extracted or calculated to analyze the pooled HR, which was estimated by fixed-effect or random-effect models based on the heterogeneity between included articles. A subgroup analysis and a meta-regression were conducted, and Galbraith plots were generated to examine any possible heterogeneity.

RESULTS

The HRs for OS were available in nine articles, whereas five articles discussed HRs for PFS. The HR with 95%CI was 1.989 (95%CI 1.522-2.600, P = 0.017, I(2)  = 57.1%) when comparing the OS of patients with 1p deletion with the OS of those without this deletion. For PFS, 1p deletion still predicted a poor prognosis (HR 2.11, 95%CI 1.54-2.88, P = 0.292, I(2)  = 19.3%). Moreover, the subgroup analysis suggested that either the deleted gene on 1p or techniques for detecting chromosome abnormalities contributed to the heterogeneity, which was partially consistent with the results derived from a meta-regression analysis and the Galbraith plot method.

CONCLUSION

Our meta-analysis provides globally quantifiable confirmation of the adverse prognostic role of 1p deletion in OS and PFS for patients with MM.

Plasma cell enrichment enhances detection of high-risk cytogenomic abnormalities by fluorescence in situ hybridization and improves risk stratification of patients with plasma cell neoplasms

CONTEXT

Methods for plasma cell enrichment of bone marrow (BM) specimens can increase the sensitivity of fluorescence in situ hybridization (FISH) for detecting cytogenomic abnormalities. There are no published reports using these methods to evaluate high-risk cytogenomic abnormalities in patients with plasma cell neoplasms (PCNs) after therapy.

OBJECTIVE

To evaluate the utility of plasma cell enrichment combined with FISH for detection of high-risk cytogenomic abnormalities in patients with PCNs after therapy.

DESIGN

Twenty-eight patients with PCNs, of whom 22 received treatment, were included in this study. Plasma cells were enriched in BM aspirates by using a magnetic cell-sorting procedure to select CD138(+) cells. Probes were chosen to assess for del(17p13/TP53), del(13q14/RB1), 1q21/CKS1B gain, IgH/FGFR3, and IgH/MAF. Clinicopathologic data were collected during clinical follow-up after plasma cell enrichment.

RESULTS

Plasma cells in nonenriched BM specimens ranged from 1% to 28% (median, 8%) compared with 28% to 96% (median, 73%) in enriched BM specimens (P < .001). In a subset of treated patients in clinical remission, FISH detected high-risk cytogenomic abnormalities only in plasma cell-enriched samples. This approach also detected abnormalities in cases of solitary plasmacytoma and monoclonal gammopathy of undetermined significance.

CONCLUSIONS

Plasma cell enrichment of BM specimens increases FISH sensitivity for detecting high-risk cytogenomic abnormalities, particularly in treated patients, and these results, in combination with clinical follow-up data, can be of value to improve risk stratification and patient management.

Understanding the molecular biology of myeloma and its therapeutic implications

Myeloma develops due to the accumulation of multiple pathological genetic events, many of which have been defined. Hyperdiploidy and reciprocal translocations centered on the immunoglobulin heavy chain variable region constitute primary genetic lesions. These primary lesions co-operate with secondary genetic events including chromosomal deletions and gains, gene mutations and epigenetic modifiers such as DNA methylation to produce the malignant phenotype of myeloma. Some of these events have been linked with distinct clinical outcome and can be used to define patient groups. This review explores the molecular biology of myeloma and identifies how genetic lesions can be used to define high- and low-risk patient groups, and also defines potential targets for therapy. The authors also explore how this information can be used to guide therapeutic decision-making and the design and interpretation of clinical trials, both now and in the future.

How I treat plasma cell leukemia

Primary plasma cell leukemia (pPCL) is a rare and aggressive plasma cell proliferative disorder with a very poor prognosis and with distinct biologic, clinical, and laboratory features. Compared with multiple myeloma, pPCL presents more often with extramedullary involvement, anemia, thrombocytopenia, hypercalcemia, elevated serum β(2)-microglobulin and lactate dehydrogenase levels, as well as impaired renal function. Many of the genetic aberrations observed in newly diagnosed pPCL are typically found in advanced multiple myeloma. These cytogenetic abnormalities and mutations lead to increased proliferation, enhanced inhibition of apoptosis, escape from immune surveillance, and independence from the BM microenvironment, with changes in expression of adhesion molecules or chemokine receptors. The outcome of pPCL has improved with the introduction of autologous stem cell transplantation and combination approaches with novel agents, including bortezomib and immunomodulatory drugs, such as lenalidomide. In this review, we provide an overview of currently available therapeutic options with recommendations of how these treatment modalities can best be used to improve outcome for plasma cell leukemia patients.

Additional genetic abnormalities significantly worsen poor prognosis associated with 1q21 amplification in multiple myeloma patients

We investigated the prognostic value of amp(1q21) alone and in combination with other abnormalities in newly diagnosed myeloma patients. The study group consisted of 104 patients treated with various induction regimens, mostly thalidomide based (87 patients). Amp(1q21) was detected in 49 (47.1%) of patients; in 26 (25.0%) cases, it was combined with del(13q14), in 7 (6.7%) with del(17p13) and in 15 (14.4%) with t(4;14)(p16;q32). The response rate was significantly better in amp(1q21)-negative than in amp(1q21)-positive patients (74.5% vs 55.1%, p = 0.025; complete response 18.2% vs 4.1%, p = 0.024). The median progression-free survival (PFS) was 33.9 months in patients without amp(1q21) and 10.3 months with this aberration (p = 0.002). The presence of additional abnormalities resulted in significantly shortened PFS when compared with patients with isolated amp(1q21): coexisting del(13q14) resulted in 7.8 vs 29.0 months of PFS (p = 0.024) and del(17p13) resulted in 4.0 vs 24.9 months of PFS (p = 0.034). The presence of amp(1q21) significantly influenced overall survival (OS) as well as PFS resulting in the median OS of 26.6 vs 62.4 months (p = 0.018) in patients without amp(1q21). The presence of additional genetic abnormalities significantly affected OS when compared with patients carrying isolated amp(1q21): for del(13q14) 18.9 vs 58.4 months (p = 0.004) and for del(17p13) 12.0 vs 46.5 months (p = 0.036). On multivariate analysis amp(1q21), del(13q14) and del(17p13) were found to be an independent adverse predictors of shorter PFS and OS. Our results showed that the presence of amp(1q21) was associated with poor prognosis. Moreover additional genetic abnormalities made PFS and OS further shortened.

Multiple myeloma: current perspectives

Multiple myeloma (MM) is a malignancy of terminally differentiated plasma cells characterized by complex genetic aberrations and heterogeneous outcomes. Over the past 25 years, cytogenetic analysis has played a key role in the diagnosis and management of MM. This article reviews the conventional cytogenetics, molecular cytogenetics, and genomic diagnostics of MM and highlights a few recent clinical trials that demonstrate the impact of genetic risk stratification on the treatment of this plasma cell malignancy.

Nuclear remodeling as a mechanism for genomic instability in cancer

This chapter focuses on the three-dimensional organization of the nucleus in normal, early genomically unstable, and tumor cells. A cause-consequence relationship is discussed between nuclear alterations and the resulting genomic rearrangements. Examples are presented from studies on conditional Myc deregulation, experimental tumorigenesis in mouse plasmacytoma, nuclear remodeling in Hodgkin's lymphoma, and in adult glioblastoma. A model of nuclear remodeling is proposed for cancer progression in multiple myeloma. Current models of nuclear remodeling are described, including our model of altered nuclear architecture and the onset of genomic instability.

Genomic stratification of multiple myeloma treated with novel agents

Cytogenetic testing is now routinely performed for the prognostic work-up of multiple myeloma (MM). The abnormalities del(17p), t(4;14) and del(13q) have been established as predictors of poor outcome in patients with MM treated with conventional chemotherapy or stem cell transplant; chromosome 1q gains and 1p losses have also been identified as novel prognostic factors. In recent years, bortezomib and lenalidomide have emerged as effective treatments for both relapsed/refractory and newly diagnosed MM. However, the effect of cytogenetic abnormalities is unclear among patients with MM treated with these novel agents. Here we review recent studies that analyze the impact of specific genomic aberrations on the outcome of MM treated with bortezomib and/or lenalidomide.