Abstract 4762: Deficient double strand breaks repair of bone marrow plasma cells correlates with better clinical outcome of multiple myeloma patients

Author(s):  
Maria Gkotzamanidou ◽  
Masood Shammas ◽  
Evangelos Terpos ◽  
Sathees C. Raghavan ◽  
Kenneth C. Anderson ◽  
...  
Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3723-3723
Author(s):  
Maria Gkotzamanidou ◽  
Masood A. Shammas ◽  
Evangelos Terpos ◽  
Enrique M. Ocio ◽  
Jesús F. San Miguel ◽  
...  

Abstract Melphalan is an interstrand cross-link (ICL)-inducing agent and one of the most active chemotherapeutic drugs in the treatment of patients with multiple myeloma (MM). There is clear evidence that the formation and subsequent persistence of ICL correlates with its cytotoxicity. Previous studies have established that during ICL repair, replication forks stall at the ICL inducing the formation of a lethal form of DNA damage (DNA double-strand breaks, DSBs), which is repaired mainly by homologous recombination (HR) and non-homologous end joining (NHEJ). In this report, we investigated the molecular mechanisms of therapeutic efficiency and drug resistance to ICL-inducing agents using melphalan as a model. We studied two MM cell lines (melphalan-sensitive RPMI-8226 and melphalan-resistant RPMI-LR5) and 70 MM patients (38 males/32 females; median age 59 years) who underwent high-dose melphalan (HDM) therapy with autologous stem cells transplantation (ASCT) as first line therapy. Patient response status was assessed 100 days after ASCT according to the International Myeloma Working Group Criteria; patients were grouped into responders (≥PR, n=48) and non-responders (<PR, n=22). Peripheral blood mononuclear cells (PBMCs) were isolated from blood samples obtained from MM patients, at diagnosis or at least 1 week prior to the treatment with any anti-myeloma drug. In addition, bone marrow plasma cells (BMPCs) were isolated from bone marrow trephine aspiration samples during diagnostic clinical assessment. Primary cells (PBMCs and BMPCs) and MM cell lines were ex vivo treated with melphalan either alone or in combination with RI-1 (selective inhibitor of HR) or NU7026 (selective inhibitor of NHEJ) and the extent of the N-ras-specific ICLs and DSBs (intermediates of ICL repair) were evaluated using a quantitative PCR assay and quantification of γH2AX foci, respectively. The γH2AX foci were viewed under a laser-scanning confocal immunofluorescence microscope and quantitated using Image J software. The induction of the apoptotic pathway by melphalan, using a photometric enzyme-immunoassay, was also studied. Following ex vivo treatment of BMPCs with melphalan, ICLs reached maximal levels within 8h of the melphalan treatment. Thereafter, ICLs levels were reduced with the repair efficiency being significantly higher in non- responders (half-time of damage removal, t1/2 23h) than in responders (t1/2 48h) (P<0.01). Moreover, γ-H2AX foci formation followed the timing of ICL formation and reached maximal levels within 8h. Thereafter, γ-H2AX foci levels declined rapidly, suggesting the resolution of the intermediate DSBs by downstream pathways (HR, NHEJ). Interestingly, the repair efficiency of DSBs in BMPCs was significantly higher in non-responders (t1/2 9h) than in responders (t1/2 12h) (P<0.02). Similar results were obtained using PBMCs. Also, in both BMPCs and PBMCs, the melphalan-induced apoptosis inversely correlated with the repair efficiencies of ICLs and DSBs, with the toxicity being higher in responders than in non-responders (P<0.01). Moreover, RPMI-LR5 cells showed higher repair efficiencies of both ICLs and DSBs and lower toxicity than RPMI-8226 cells. Interestingly, in all cell types analyzed, significant correlation between ICL and DSBs levels was observed (linear regression analysis, R2=0.67, P<0.01). To further elucidate the mechanism of drug-induced DSBs repair, MM cell lines and primary cells (BMPCs and PBMCs) were treated with melphalan in combination with nontoxic doses of RI-1 or NU7026. We found that the combined treatment of melphalan with RI-1 or NU7026 significantly increased the melphalan only-induced phosphorylation of H2AX (suggesting that both HR and NHEJ contribute to the repair of melphalan-induced DSBs), delayed the repair of ICLs and strongly enhanced the cytotoxic activity of melphalan (all P<0.01). Collectively, these results highlight that in BMPCs significant changes in the repair efficiency of DSBs occur in MM patients. These changes affect the removal of the cytotoxic ICLs, modify drug sensitivity of the malignant plasma cells ex vivo, and correlate with the clinical outcome of anti-myeloma therapy. Interestingly, these changes are also reflected in PBMCs. Specific inhibition of HR and/or NHEJ may be useful as an adjunct to melphalan therapy in MM patients. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
1984 ◽  
Vol 64 (2) ◽  
pp. 352-356
Author(s):  
GJ Ruiz-Arguelles ◽  
JA Katzmann ◽  
PR Greipp ◽  
NJ Gonchoroff ◽  
JP Garton ◽  
...  

The bone marrow and peripheral blood of 14 patients with multiple myeloma were studied with murine monoclonal antibodies that identify antigens on plasma cells (R1–3 and OKT10). Peripheral blood lymphocytes expressing plasma cell antigens were found in six cases. Five of these cases expressed the same antigens that were present on the plasma cells in the bone marrow. Patients that showed such peripheral blood involvement were found to have a larger tumor burden and higher bone marrow plasma cell proliferative activity. In some patients, antigens normally found at earlier stages of B cell differentiation (B1, B2, and J5) were expressed by peripheral blood lymphocytes and/or bone marrow plasma cells.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Byung-Hyun Lee ◽  
Yong Park ◽  
Ji Hye Kim ◽  
Ka-Won Kang ◽  
Seung Jin Lee ◽  
...  

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3948-3948
Author(s):  
Jeremy T Larsen ◽  
Shaji Kumar ◽  
S. Vincent Rajkumar

Abstract Abstract 3948 Background: Smoldering multiple myeloma (SMM) is an asymptomatic precursor disease of multiple myeloma, and is defined by excess bone marrow plasma cells and monoclonal protein without evidence of end-organ damage (hypercalcemia, renal insufficiency, anemia, or bone lesions [CRAB]). The identification of SMM patients with more aggressive underlying disease remains a challenge. We hypothesize that SMM is a clinical entity comprised of both premalignant, high-risk MGUS and early multiple myeloma in transition to malignant disease, which may be differentiated with the use of the serum FLC (FLC) ratio. Methods: This was a retrospective analysis of 586 patients with newly diagnosed SMM from 1970–2010 with available stored serum samples around the time of diagnosis to be utilized for quantification of FLC ratios. SMM was defined by the International Myeloma Working Group 2003 definition; serum M-protein ≥ 3 g/dL and/or ≥ 10% bone marrow plasma cells with no evidence of CRAB features. The immunoglobulin FLC assay (Binding Site, U.K.) was used for testing. The FLC ratio was calculated as κ/λ (reference range 0.26–1.65). The involved/uninvolved FLC ratio was recorded to simplify the reporting of data. Receiver Operating Characteristics (ROC) curves were created to assess the ability of the FLC ratio to discriminate patients who progressed to symptomatic multiple myeloma (MM) in the first 2 years or at any point during follow-up versus patients without evidence of progression. Patients with less than 24 months follow-up without progression were censored. The optimal diagnostic cut-point for FLC involved/uninvolved ratio to identify patients with progressive disease from the ROC curve was >88.6 (equivalent to <0.011 or >88.6). For ease of clinical application, the optimal value for involved/uninvolved FLC ratio was rounded to >100. Time to progression (TTP) from date of the initial FLC to active MM was calculated using Kaplan-Meier analysis and compared to patients with a high (>100) and low (<100) involved/uninvolved FLC ratio at time of SMM diagnosis. TTP within 24 months of the initial FLC was also calculated. Results: During the study period, 54% of patients progressed to active MM. On ROC analysis, a cut-point of >100 corresponded to a sensitivity of 25% (95% CI, 20.5–30.4) and specificity of 99.3% (97.3–99.9), with positive likelihood (+LR) ratio of 33.9 (38.1–41.0), negative likelihood ratio (−LR) of 0.75 (0.2–3.0), positive predictive value (PPV) of 97.6 (91.5–99.7) and negative predictive value of 53.0 (48.5–57.4). Using the ROC to assess progression to MM within 24 months (Figure 1), sensitivity was 29.6% (23.5–36.4), specificity 94.5% (91.7–96.5), +LR 5.36 (4.3–6.6), -LR 0.75 (0.5–1.1), PPV 85.8 (77.7–91.8), and NPV 54.3 (49.8–58.9). Median TTP to active MM in the FLC >100 group was 15 months (9–17) versus 52 months (44–60) in the FLC <100 group (p <.0001) [Figure 2]. In the FLC ratio >100 group, progression at 1 year was 47%, 76% at 2 years, and 90% at 3 years. Only 25% of the FLC <100 patients had progressed at 2 years. The most common progression event was bone disease (42%), followed by anemia (26%), renal impairment (23%), and hypercalcemia (5%). Conclusion: Elevation of the FLC ratio >100 (or <0.01) is highly specific for the future development of active MM, with 76% of these patients developing end-organ damage requiring therapy within 2 years. Risk of transformation to MM in the FLC <100 group was similar to previously reported rates of 10% per year for the first 5 years. Development of an FLC ratio >100 is associated with increasing disease burden and in this study behaved in a malignant fashion rather than a precursor state. The FLC is a simple and useful predictor of progression to MM in SMM, and patients with FLC ratios of <0.01 or >100 within the first 2 years of SMM diagnosis should be monitored especially closely. Future studies are needed to determine optimum cutoffs for FLC ratio to where a change in definition of MM could be considered. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 3985-3985
Author(s):  
Francesca Fontana ◽  
Josè Manuel garcia Manteiga ◽  
Magda Marcatti ◽  
Francesca Lorentino ◽  
Giovanni Tonon ◽  
...  

Abstract Abstract 3985 Multiple myeloma is a malignancy of plasma cells, which grows at multiple foci in the bone marrow, secretes monoclonal immunoglobulins, and typically induces skeletal destruction, hypercalcemia, anemia, and renal failure. Although it remains an incurable cancer, novel therapeutic regimens have improved overall survival in the last decade. Multiple myeloma originates from post germinal center, terminally differentiated B lymphocytes through a multi-step process involving early and late genetic changes. Multiple myeloma is preceded by monoclonal gammopathy of undetermined significance (MGUS), a frequent age-progressive premalignant expansion of bone marrow plasma cells that behave benignly despite the presence of most myeloma-specific genetic abnormalities. Indeed, development and progression of multiple myeloma are believed to rely on vicious interactions with the bone marrow environment, offering a paradigm to investigate the bone-cancer relationship. In particular, bone and stromal cells are known to be diverted by cancer cells through altered cytokine circuitry. The resulting enhanced osteoclastogenesis and neoangiogenesis, and reduced osteoblast differentiation and activity sustain cancer cell survival, proliferation, migration and chemoresistance. Such crucial interactions, however, have only partially been elucidated in their complexity, dynamics and exact role in disease evolution. A better knowledge of this interplay, still elusive, could help identify prognostic markers, pathomechanisms, and therapeutic targets for future validation. Aiming to achieve an unbiased, comprehensive assessment of the extracellular milieu during multiple myeloma genesis and progression, we performed a metabolomic analysis of patient-derived peripheral and bone marrow plasma by ultra high performance liquid and gas chromatography followed by mass spectrometry. By feature transformation-based multivariate analyses, metabolic profiling of both peripheral and bone marrow plasma successfully discriminated active disease from control conditions (health, MGUS or remission). Moreover, both central and peripheral metabolic scores significantly correlated with bone marrow plasma cell counts. Significant changes in the peripheral metabolome were found to be associated with abnormal renal function in the subset of myeloma patients. Noteworthy, however, renal dysfunction-associated features failed to independently predict disease load, while non-overlapping disease vs. control analyses consistently identified a number of metabolites associated with disease. Among these, increased levels of the C3f-derived peptide, HWESASLL, and loss of circulating lysophosphocholines emerged as hallmarks of active disease. In vitro tests on myeloma cell lines and primary patient-derived cells revealed a previously unsuspected direct trophic role exerted by lysophosphocholines on malignant plasma cells. Altogether, our data demonstrate that metabolomics is a powerful approach suitable for studying the complex interactions of multiple myeloma with the bone marrow environment and general metabolism. This novel strategy holds potential to identify unanticipated markers and pathways involved in development and progression of multiple myeloma. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 311-311 ◽  
Author(s):  
Laurie Herviou ◽  
Alboukadel Kassambara ◽  
Stephanie Boireau ◽  
Nicolas Robert ◽  
Guilhem Requirand ◽  
...  

Abstract Multiple Myeloma is a B cell neoplasia characterized by the accumulation of clonal plasma cells within the bone marrow.Epigenetics is characterized by a wide range of changes that are reversible and orchestrate gene expression. Recent studies have shown that epigenetic modifications play a role in multiple myeloma (MM) by silencing various cancer-related genes. We investigated the epigenetic genes differentially expressed between normal bone marrow plasma cells (BMPC ; N=5) and MM plasma cells from patients (N=206). Using SAM (Significance Analysis of Microarrays) analysis, only 12 genes significantly differentially expressed between BMPC and MM cells (ratio > 2 and FDR (false discovery rate) < 5%) were identified, including the EZH2 histone methyltransferase. EZH2, the enzymatic subunit of Polycomb Repressive Complex 2, is a histone methyltransferases able to repress gene expression by catalyzing H3K27me3 histone mark. EZH2 overexpression has been associated with numerous hematological malignancies, including MM. We thus studied EZH2 role in MM physiopathology and drug resistance. EZH2 expression was analyzed in normal bone marrow plasma cells (BMPCs; N=5), primary myeloma cells from newly diagnosed patients (MMCs; N=206) and human myeloma cell lines (HMCLs; N=40) using Affymetrix microarrays. EZH2 gene is significantly overexpressed in MMCs of patients (median 574, range 105 - 4562) compared to normal BMPCs (median = 432; range: 314 - 563) (P < 0.01). The expression is even higher in HMCLs (median 4481, range 581 - 8455) compared to primary MMCs or BMPCs (P < 0.001). High EZH2 expression is associated with a poor prognosis in 3 independent cohorts of newly diagnosed patients (Heidelberg-Montpellier cohort - N=206, UAMS-TT2 cohort - N=345 and UAMS-TT3 cohort - N =158). Furthermore, GSEA analysis of patients with high EZH2 expression highlighted a significant enrichment of genes involved in cell cycle, downregulated in mature plasma cells vs plasmablasts, and EZH2 targets. Specific EZH2 inhibition by EPZ-6438 EZH2 inhibitor induced a significant decrease of global H3K27me3 in all the HMCLs tested (P < 0.01) and inhibited MM cell growth in 5 out of the 6 HMCLs tested. The inhibitory effect of EZH2 inhibitor on MM cell growth appeared at day 6 suggesting that it is mediated by epigenetic reprogramming. To confirm that EZH2 is also required for the survival of primary MMCs from patients, primary MM cells (n = 17 patients) co-cultured with their bone marrow microenvironment and recombinant IL-6 were treated with EPZ-6438. As identified in HMCLs, EZH2 inhibition significantly reduced the median number of viable myeloma cells by 35% (P = 0.004) from a subset of patients (n=9) while the other group (n=8) was resistant. Of interest, EPZ-6438 induced a significant global H3K27me3 decrease in both groups of patient. RNA sequencing of 6 HMCLs treated with EPZ-6438 combined with H3K27me3 ChIP analyses allowed us to create an EZ GEP-based score able to predict HMCLs and primary MM cells sensitivity to EZH2 inhibitors. We also observed a synergy between EPZ-6438 and Lenalidomide, a conventional drug used for MM treatment. More interestingly, pretreatment of myeloma cells with EPZ-6438 significantly re-sensitize drug-resistant MM cells to Lenalidomide. Investigating the effect of EPZ-6438/Lenalidomide combination in MMC, we identified that IKZF1, IRF4 and MYC protein levels were significantly more inhibited by the combination treatment (65.5%, 63.9% and 14.8% respectively) compared with Lenalidomide (51.5%, 43% and 2.2%) or EPZ-6438 (45.2%, 38.7% and 6.2%) alone. Clinical trials are ongoing with EZH2 inhibitors in lymphoma and could be promising for a subgroup of MM patients in combination with IMiDs. Furthermore, the EZ score enables identification of MM patients with an adverse prognosis and who could benefit from treatment with EZH2 inhibitors. Disclosures Goldschmidt: Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Onyx: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Membership on an entity's Board of Directors or advisory committees, Research Funding; Millennium: Membership on an entity's Board of Directors or advisory committees, Research Funding; Chugai: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees. Hose:EngMab: Research Funding; Takeda: Other: Travel grant; Sanofi: Research Funding.


Leukemia ◽  
2005 ◽  
Vol 19 (8) ◽  
pp. 1466-1470 ◽  
Author(s):  
S Kumar ◽  
S V Rajkumar ◽  
T Kimlinger ◽  
P R Greipp ◽  
T E Witzig

2017 ◽  
Vol 92 (9) ◽  
pp. E507-E512 ◽  
Author(s):  
Toshi Ghosh ◽  
Wilson I. Gonsalves ◽  
Dragan Jevremovic ◽  
Angela Dispenzieri ◽  
David Dingli ◽  
...  

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