Multiple Myeloma: Available Therapies and Causes of Drug Resistance

Risk of infections in bispecific antibody therapy for multiple myeloma: a comprehensive review of literature

Multiple Myeloma (MM) is a malignancy characterized by abnormal production of monoclonal immunoglobulins in plasma cells. Bispecific antibodies have emerged as a significant advancement in MM treatment, offering high effectiveness and specificity by targeting different antigens such as BCMA, CD38, and FcRH5. However, the risk of infection poses a major challenge in MM patients, which is thought to be influenced by various factors.The overall risk of infections associated with the use of BsAbs is estimated to be approximately 56% for all grades, with Grade 3/4 infections accounting for 24% of cases. Notably, BCMA-targeted BsAbs are associated with a higher incidence of infections compared to other targets. Risk factors contributing to infection occurrence include BsAbs risk of neutropenia and hypogammaglobulinemia as well as the inherent nature of the disease and patient-related factors. Bacterial infections, particularly respiratory tract and gastrointestinal infections are the most commonly reported, while viral infections such as CMV and rhinovirus are also prevalent in patients receiving BsAbs. Additionally, fungal infections have been documented in MM patients. Prophylactic measures for bacterial and fungal infections are tailored based on individual patient risk assessments, while viral infection prophylaxis is recommended for all refractory/relapsed MM patients receiving BsAbs.

Multiple Myeloma in Italy: An Epidemiological Model by Treatment Line and Refractoriness Status

BACKGROUND

Multiple myeloma (MM) clinical management is challenging owing to its relapse and refractoriness to treatment. Understanding the treatment patterns and refractory dynamics is crucial for optimizing patient care. This study aimed to estimate the evolution of MM according to the treatment line and refractoriness status in Italy.

MATERIALS AND METHODS

A new epidemiological model was developed using epidemiological and clinical data from literature. Prevalent MM patients were characterized by calibrating the model inputs. Incident patients were included starting in 2021, when antiCD38-containing regimens were reimbursed as first-line treatments in Italy. The model employed a 1-year cycle Markov structure to simulate patient flow through the treatment lines, accounting for the development of lenalidomide and anti-CD38 monoclonal antibody (mAb) refractoriness.

RESULTS

In 2020, Italy had an estimated 33,734 prevalent MM patients. By 2027, treated patients were projected to increase from 28,499 to 35,074. The introduction of lenalidomide and mAb therapies in earlier lines has resulted in a higher accumulation of patients in the early lines, with a corresponding decrease in the proportion of patients requiring subsequent lines of therapy. Furthermore, the proportion of patients refractory to both lenalidomide and mAbs in the second to fourth lines of treatment is estimated to increase from 1.6% in 2021 to 29.7% by 2027.

CONCLUSION

Our model revealed a rising prevalence of patients receiving first-line treatment owing to more effective treatments. The marked increase in the number of refractory patients in subsequent lines underscores the urgent need for innovative therapies to address treatment resistance.

Bone Marrow-Targeted Liposomes Loaded with Bortezomib Overcome Multiple Myeloma Resistance

Multiple myeloma (MM) poses a significant therapeutic challenge due to its persistent progression and low survival rate. Although the proteasome inhibitor bortezomib has revolutionized MM treatment, MM aggressiveness and drug resistance remain critical concerns. To tackle this problem, we developed AMD3100-targeted Bortezomib Liposomes (ATBL) designed for the targeted delivery of bortezomib to MM cells. Uptake of ATBL into MM cells was dependent on CXCR4 and was enhanced compared to nontargeted liposomes, both in vitro and in vivo. Treating MM-bearing mice with ATBL achieved superior therapeutic efficacy compared to treatment with free bortezomib or nontargeted bortezomib-loaded liposomes. Notably, the therapeutic activity of ATBL was limited in mice inoculated with CXCR4-knockdown MM cells, highlighting CXCR4 as a potential biomarker for ATBL response. Importantly, ATBL was effective against an aggressive and bortezomib-resistant MM clone both in vitro and in vivo. Toxicity and biodistribution profiles demonstrated the safety and bone marrow-targeting ability of ATBL. Collectively, this study highlights ATBL as a promising next-generation proteasome inhibitor-based therapy that incorporates bone marrow-targeting ability and sensitizing elements to overcome drug resistance in MM.

Prognostic and clinicopathological value of the controlling nutritional status score in patients with multiple myeloma: a meta-analysis

Background

The effect of the controlling nutritional status (CONUT) score on forecasting multiple myeloma (MM) prognosis is previously analyzed, whereas the results remained inconsistent. The present meta-analysis focused on identifying the exact function of CONUT in forecasting MM prognosis.

Methods

Web of Science, PubMed, Embase, CNKI, and Cochrane Library were comprehensively searched between inception and 1 February 2025. The effect of CONUT on forecasting MM overall survival (OS) and progression-free survival (PFS) was determined by computing pooled hazard ratios (HRs) together with 95% confidence intervals (CIs).

Results

There were nine studies with 1,176 patients being recruited into the present work. As indicated by our pooled data, elevated CONUT was related to the dismal OS (HR = 1.87, 95% CI = 1.37-2.54, p < 0.001) of patients with MM. Nonetheless, CONUT was not significantly related to PFS (HR = 1.33, 95% CI = 0.81-2.19, p = 0.254) of MM. Furthermore, higher CONUT score showed a significant relationship to bone marrow plasma cells >30% (OR = 2.30, 95% CI = 1.32-3.99, p = 0.003). On the other hand, CONUT was not markedly correlated with gender (OR = 2.68, 95% CI = 0.81-8.82, p = 0.105), ISS stage (OR = 1.28, 95% CI = 0.94-1.75, p = 0.119), or ECOG PS (OR = 1.30, 95% CI = 0.84-2.01, p = 0.234) of MM.

Conclusion

Collectively, according to our results in this meta-analysis, higher CONUT score is markedly related to dismal OS, but not PFS in patients with MM. CONUT score can be used as a candidate marker used to predict MM prognosis in the clinic in the future.

Novel Pan-ALDH Inhibitor KS100 Effectively Targets ALDH+/CD138⁻ Stem-like Cells to Overcome Relapse in Multiple Myeloma

Multiple myeloma (MM), a clonal plasma cell disorder is the second most frequent hematological malignancy in the United States. This malignancy is characterized by a series of symptoms such as bone lesions, hypercalcemia, renal failure, and anemia. The current clinical drugs in the market are successful in treating multiple myeloma patients into remission but does not address relapse where a more aggressive phenotype of the cancer remains untreatable. We hypothesize that a small subset of multiple myeloma stem-like cells (MMSLC's) that overexpress aldehyde dehydrogenases (ALDH + ) is the cause of the relapse. Overexpression of ALDH bolsters drug resistance via detoxification and stemness via the retinoic acid signaling pathway. The phenotype of MMSLC's is not yet known for certainty but there are a few well established markers such CD138 negative (CD138 neg ) cells that are known to overexpress ALDH. In this study, we target regular MM cells and bortezomib resistant ALDH + /CD138 neg MMSLC's with a novel, potent, pan-ALDH inhibitor, KS100. Here we report KS100 effectively lowered ALDH expression in regular and bortezomib resistant ALDH + /CD138 neg cells, MM cell viability as well as proteins associated with MMSLC's. Most importantly we showed that KS100 lowered ALDH + populations in regular, bortezomib resistant and CD138 neg cells via ALDEFLUOR™ assay.

Comprehensive bioinformatics analysis reveals key hub genes linked to prognosis in multiple myeloma with drug resistance

Multiple myeloma (MM) is an incurable hematologic malignancy, with chemotherapy being the primary treatment. However, the development of drug resistance remains a major challenge. This study aimed to identify therapeutic targets associated with drug resistance in MM and assess their prognostic significance. Gene expression data from GSE82307, GSE146649, and GSE136725 were analyzed to identify differentially expressed genes (DEGs) using the "limma" and "RobustRankAggreg" R packages. Functional enrichment analysis and protein-protein interaction (PPI) network analysis were performed, with key network modules identified using Cytoscape. The expression and prognostic relevance of DEGs were validated using MM patient samples from the GSE136725 and MMRF CoMMpass databases. A total of 4623 DEGs were identified, and robust rank aggregation analysis revealed the top 20 upregulated genes. Among them, AURKA, DLGAP5, BUB1B, and KIF20A were highly expressed in drug-resistant patients and were associated with poor prognosis. The findings suggest that AURKA, DLGAP5, BUB1B, and KIF20A are potential biomarkers linked to drug resistance and recurrence in MM. Further studies are required to elucidate the underlying molecular mechanisms and explore their potential as therapeutic targets.

Multiple Myeloma: Improved Outcomes Resulting from a Rapidly Expanding Number of Therapeutic Options

Multiple myeloma (MM) is a bone-marrow-based cancer of plasma cells. Over the last 2 decades, marked treatment advances have led to improvements in the overall survival (OS) of patients with this disease. Key developments include the use of chemotherapy, immunomodulatory drugs, proteasome inhibitors, and monoclonal antibodies. MM remains incurable, with outcomes influenced by many factors, including age, sex, genetics, and treatment response. This review summarizes recent studies regarding monitoring and treatment of MM, emphasizing the efficacy of new therapies, the impact of maintenance treatments, and approaches for managing relapsed or refractory MM. The role of specific drug classes used to treat MM, including immunomodulatory drugs, proteasome inhibitors, monoclonal antibodies, and newer treatments such as chimeric antigen receptor T-cell therapies and bispecific antibodies are discussed. Combination therapies have significantly improved outcomes. Maintenance therapies, particularly with lenalidomide, have been effective in extending OS but lead to an increased risk of secondary cancers. Venetoclax, selinexor, and ruxolitinib have shown potential as new therapeutic options for patients with relapsed or refractory MM. Immune-based treatments, such as chimeric antigen receptor T-cell therapy and bispecific antibodies, mark a major advancement for heavily pretreated patients, although challenges remain related to cost, availability, and side effects. The treatment landscape for patients with MM has seen significant progress, with current therapies providing a longer OS and better quality of life. Future research should focus on optimizing these strategies, personalizing therapies, and exploring new therapeutic targets.

Talquetamab Versus Real-World Physician's Choice Treatment: Comparative Effectiveness in Patients With Triple-Class Exposed Relapsed/Refractory Multiple Myeloma

BACKGROUND

Talquetamab is approved for treatment of triple-class exposed (TCE) patients with relapsed/refractory multiple myeloma (RRMM). We evaluated the comparative effectiveness of talquetamab in the MonumenTAL-1 study versus real-world physician's choice (RW) treatment.

MATERIALS AND METHODS

An external control arm for MonumenTAL-1 was created from patients in the Flatiron Health database who satisfied MonumenTAL-1 eligibility criteria (n = 629 with 1169 eligible lines of therapy). Patient-level data from MonumenTAL-1 were included for patients who received subcutaneous talquetamab 0.4 mg/kg QW (n = 143) and 0.8 mg/kg Q2W (n = 145). After adjusting for baseline covariate imbalances, comparative effectiveness was assessed for progression-free survival (PFS), time to next treatment (TTNT), and overall survival (OS).

RESULTS

Baseline covariates were comparable across cohorts after adjustment. Talquetamab 0.4 mg/kg QW and 0.8 mg/kg Q2W cohorts, respectively, showed significant improvement in PFS (HR, 0.55 [95% CI, 0.44-0.69; P < .0001; median, 7.5 vs. 4.0 months] and 0.40 [95% CI, 0.31-0.53; P < .0001; median, 14.2 vs. 4.0 months]), TTNT (HR, 0.59 [95% CI, 0.47-0.74; P < .0001; median, 9.1 vs. 5.1 months] and 0.45 [95% CI, 0.35-0.59; P < .0001; median, 13.3 vs. 5.1 months]), and OS (HR, 0.56 [95% CI, 0.40-0.78; P = .0007; median, NR vs. 16.5 months] and 0.48 [95% CI, 0.33-0.70; P = 0.0002; median NR vs. 15.9 months]) versus RW treatment.

CONCLUSION

Both talquetamab schedules demonstrated superior effectiveness over RW treatment for all outcomes assessed. These data suggest talquetamab as an effective immunotherapy option in patients with TCE RRMM.

A Phase 1/2 study of teclistamab, a humanized BCMA × CD3 bispecific Ab in Japanese patients with relapsed/refractory MM

We characterized the safety and efficacy of the bispecific antibody teclistamab in Japanese patients with relapsed/refractory multiple myeloma (RRMM). Patients were pretreated with a proteasome inhibitor (PI), immunomodulatory drug (IMiD), and anti-CD38 monoclonal antibody (mAb). The primary endpoint was frequency and type of treatment-emergent adverse events (TEAEs) in phase 1, and overall response rate (ORR; ≥ partial response [PR]) in phase 2. In phase 1, 14 patients received once-weekly (QW) subcutaneous teclistamab (0.72 mg/kg [n = 5]; 1.5 mg/kg [n = 5]; 3 mg/kg [n = 4]). No dose-limiting toxicities were observed. As of April 2024, 26 phase-2 patients received the recommended phase-2 dose (QW) (RP2D: 1.5 mg/kg) of teclistamab. Biweekly (Q2W) dosing was allowed after maintaining response for ≥ 6 months. At a median follow-up of 14.32 months, ORR was 76.9% (≥ very good PR: 76.9%; ≥ complete response: 65.4%). Median duration of response, progression-free survival, and overall survival were not reached. Common TEAEs included CRS (grade ≤ 2), neutropenia, and infections. No patient had immune effector cell-associated neurotoxicity syndrome (ICANS) and dose reductions. Teclistamab demonstrated deep and durable responses in Japanese patients with RRMM, consistent with the global pivotal MajesTEC-1 study, supporting the potential for a new standard of care for Japanese RRMM patients.

Targeting deubiquitinase USP7-mediated stabilization of XPO1 contributes to the anti-myeloma effects of selinexor

BACKGROUND

Targeting exportin1 (XPO1) with Selinexor (SEL) is a promising therapeutic strategy for patients with multiple myeloma (MM). However, intrinsic and acquired drug resistance constitute great challenges. SEL has been reported to promote the degradation of XPO1 protein in tumor cells. Nevertheless, in myeloma, the precise mechanisms underlying SEL-induced XPO1 degradation and its impact on drug responsiveness remain largely undefined.

METHODS

We assessed XPO1 protein and mRNA levels using western blotting and RT-qPCR. Cycloheximide (CHX) chase assays and degradation blockade assays were used to determine the pathway of XPO1 degradation induced by SEL. The sensitivity of MM cell lines to SEL was evaluated using CCK8-based cell viability assays and AV-PI staining-based cell apoptosis assays. The subcellular localization of the cargo protein RanBP1 was assessed via immunofluorescence staining. Immunoprecipitation coupled with mass spectrometry (IP-MS), bioinformatics analysis and ubiquitination assays, were employed to identify the molecular targets responsible for SEL-induced degradation of XPO1. shRNA-mediated knockdown assays and small molecule inhibitors of USP7 were utilized to disrupt the function of USP7. The role of USP7 in modulating SEL sensitivity was analyzed in MM cell lines, primary CD138+ cells, and xenograft mouse models.

RESULTS

SEL promotes the degradation of XPO1 in MM cells through the ubiquitin-proteasome pathway. There is a positive correlation between XPO1 degradation and sensitivity to SEL in these cells. Inhibiting XPO1 degradation reduces the functional inhibitory effects of SEL on XPO1, as evidenced by decreased nuclear localization of the cargo protein RanBP1. USP7 stabilizes XPO1 in MM cells via its deubiquitinating activity. SEL accelerates the ubiquitination and subsequent degradation of XPO1 by disrupting the interaction between XPO1 and USP7. The expression of USP7 is negatively correlated with patient prognosis and the sensitivity of MM cells to SEL. Inactivating or knocking down USP7 significantly enhances the anti-myeloma effects of SEL both in vitro and in vivo.

CONCLUSION

In conclusion, our findings underscore the essential role of XPO1 degradation in the anti-myeloma efficacy of SEL and establish a research foundation for targeting USP7 to improve the effectiveness of SEL-based therapies in MM.

A systematic literature review on clonal evolution events preceding relapse in multiple myeloma

Despite considerable treatment advances, multiple myeloma (MM) remains an incurable hematological cancer due to treatment resistance. A systematic literature search was conducted to identify determinants for clonal evolution driving relapse and drug resistance in MM. A total of 631 non-duplicate publications were screened of which 28 articles were included for data extraction. Genetic alterations, mutational signatures, evolutionary trajectories, and non-genetic determinants were identified as key topics to characterize clonal evolution in relapsed MM. A variety of factors led to clonal diversification and increased tumor mutation burden, such as MAPK-Ras mutations and incremental changes related to chromosomal bands 1 and 17, while mutational signature analyses revealed that APOBEC activity and melphalan treatment leave a distinct impact on the clonal composition in MM genomes. To capture and dissect tumor heterogeneity, our review suggests combining methods or using technical approaches with high resolution to assess the impact of clonal evolution.

Visualizing immunotherapy for multiple myeloma worldwide from 2013 to 2023: A bibliometric analysis

Multiple myeloma (MM) is a malignant, clonal proliferative disease of plasma cells that remains incurable. This paper aims to analyze the current research status and emerging trends in immunotherapy for MM through bibliometric methods, thereby providing valuable references and guidance for future research and clinical practice. This study presents a bibliometric analysis of 1,018 English-language publications related to MM immunotherapy, which were published in the Web of Science (WoS) Core Collection database from 2013 to 2023. VOSviewer and CiteSpace were employed to visualize the research hotspots and trends within the field of MM immunotherapy. The United States had the highest number of publications (n = 432, 42.44%), followed by China (n = 177, 17.39%). Harvard University was the institution with the most publications (n = 85), while Anderson KC (n = 27) was the most prolific researcher in the field. The highly cited literature mainly focuses on the treatment regimen based on daratumumab, the application of BCMA CAR-T therapy and the management of relapsed/refractory MM (RRMM), which represent the current research hotspots in this field. Burst detection highlights that bispecific antibodies and preclinical activity as key areas of interest. The cooperation among countries, institutions, and authors in this field should be strengthened. The treatment regimen utilizing daratumumab, the implementation of BCMA CAR-T therapy, and the management of RRMM represent significant research focal points in this field. Additionally, the development and application of bispecific antibodies have emerged as a frontier in recent years.

Disrupting USP39 deubiquitinase function impairs the survival and migration of multiple myeloma cells through ZEB1 degradation

BACKGROUND

Multiple Myeloma (MM) is the second most common hematological malignancy, characterized by the accumulation of monoclonal plasmocytes in the bone marrow. Despite advancements with proteasome inhibitors, immunomodulatory agents, and CD38-targeting antibodies, MM remains largely incurable due to resistant clones and frequent relapses. The success of the proteasome inhibitor bortezomib (BTZ) in MM treatment highlights the critical role of the ubiquitin-proteasome system (UPS) in this disease. Deubiquitinases (DUBs), which regulate protein stability, interactions, and localization by removing ubiquitin modifications, have emerged as promising therapeutic targets in various cancers, including MM.

METHODS

Through a comprehensive loss-of-function screen, we identified USP39 as a critical survival factor for MM cells. Gene Set Enrichment Analysis (GSEA) was employed to correlate USP39 mRNA levels with clinical outcomes in MM patients. USP39 protein expression was evaluated via immunohistochemistry (IHC) on bone marrow samples from MM patients and healthy controls. The impact of USP39 knockdown via SiRNA was assessed through in vitro assays measuring cellular metabolism, clonogenic capacity, cell cycle progression, apoptosis, and sensitivity to BTZ. Co-immunoprecipitation and deubiquitination assays were conducted to elucidate the interaction and regulation of ZEB1 by USP39. Finally, in vitro and in vivo zebrafish experiments were used to characterize the biological consequences of ZEB1 regulation by USP39.

RESULTS

Our study found that elevated USP39 mRNA levels are directly associated with shorter survival in MM patients. USP39 protein expression is significantly higher in MM patient plasmocytes compared to healthy individuals. USP39 knockdown inhibits clonogenic capacity, induces cell cycle arrest, triggers apoptosis, and overcomes BTZ resistance. Gain-of-function assays revealed that USP39 stabilizes the transcription factor ZEB1, enhancing the proliferation and the trans-migratory potential of MM cells.

CONCLUSIONS

Our findings highlight the critical role of the deubiquitinase USP39, suggesting that the USP39/ZEB1 axis could serve as a potential diagnostic marker and therapeutic target in MM.

The evolving treatment landscape of multiple myeloma in Portugal: A nation-wide retrospective cohort study of real-world clinical practice

Objectives

To characterize variations in real-world treatment patterns in multiple myeloma (MM) in Portugal over a 5-year period.

Methods

A retrospective cohort multicenter study using secondary data of national hospital drug consumption database from 11 Portuguese public hospitals between 2017 and 2022.

Results

Number of MM-treated patients increased 53% over 5 years (from 825 to 1266 patients). Constant slight predominance of male patients (55%), 82% over 60 years old (median age, 70 years), and half of newly diagnosed patients were transplant-eligible. The highest growth rate was in second-line treatments, with a sixfold increase in patients in fourth-line or beyond. First-line treatment pattern remained stable both in transplant-eligible (bortezomib, cyclophosphamide and dexamethasone (VCd_, bortezomib, thalidomide and dexamethasone (VTd), and bortezomib, lenalidomide and dexamethasone (VRd)) and noneligible patients (bortezomib, melphalan and prednisolone (VMP), VCd, and lenalidomide, dexamethasone (Rd)). Maintenance therapy increased from 5% to 16%, shifting from thalidomide to lenalidomide. Second and third lines were dominated by daratumumab-based regimens after 5 years. No standard of care in fourth-line treatment. Treatment duration increased in transplant-eligible due to maintenance therapy and in noneligible due to fourth-line treatments. Patients moved from first- to second-line more rapidly over time.

Conclusions

There was an increase in MM patients reaching advanced treatment lines and significant changes in the treatment patterns, driven by access to more effective frontline treatments and longer duration of treatment.

Multiple myeloma: clinical characteristics, current therapies and emerging innovative treatments targeting ribosome biogenesis dynamics

Multiple myeloma (MM) is a clinical disorder characterized by aberrant plasma cell growth in the bone marrow microenvironment. Globally, the prevalence of MM has been steadily increasing at an alarming rate. In the United States, more than 30,000 cases will be diagnosed in 2024 and it accounts for about 2% of cancer diagnoses and more than 2% of cancer deaths, more than double the worldwide figure. Both symptomatic and active MM are distinguished by uncontrolled plasma cell growth, which results in severe renal impairment, anemia, hypercalcemia, and bone loss. Multiple drugs have been approved by the FDA and are now widely used in clinical practice for MM. Although triplet and quadruplet induction regimens, autologous stem cell transplantation (ASCT), and maintenance treatment are used, MM continues to be an incurable illness characterized by relapses that may occur at various phases of its progression. MM patients with frailty, extramedullary disease, plasma cell leukemia, central nervous system recurrence, functional high risk, and the elderly are among those with the greatest current unmet needs. The high cost of care is an additional challenge. MM cells are highly protein secretary cells and thus are dependent on the activation of certain translation pathways. MM also has a high chance of altering ribosomal protein-encoding genes like MYC mutation. In this article we discuss the importance of ribosome biogenesis in promoting MM and RNA polymerase I inhibition as an upcoming treatment with potential promise for MM patients.

PHF19 before and post induction treatment possess favorable potency of reflecting treatment response to protease inhibitors, event-free survival, and overall survival in multiple myeloma patients

OBJECTIVE

Plant homeodomain finger protein 19 (PHF19) regulates hematopoietic stem cell differentiation and promotes multiple myeloma (MM) progression. This study intended to explore the potency of PHF19 at baseline and post induction treatment in estimating treatment response to protease inhibitors and survival in MM patients.

METHODS

This retrospective study screened 69 MM patients who received protease inhibitors with bone marrow (BM) samples available at both baseline and post induction treatment. Twenty healthy BM donors were included as healthy controls (HCs). PHF19 in plasma cells from BM was quantified by reverse transcription-quantitative polymerase chain reaction.

RESULTS

PHF19 at baseline and post induction treatment in MM patients were increased than in HCs. In MM patients, PHF19 was declined post induction treatment. Elevated PHF19 at baseline and post induction treatment were correlated with renal impairment, beta-2-microglobulin ≥5.5 mg/L, t (4; 14), higher international staging system (ISS) stage, and higher revised ISS (R-ISS) stage. Concerning treatment response, PHF19 at baseline and post induction treatment were negatively associated with complete response and overall response rate. Notably, abnormal PHF19 (above 95% quantile value of PHF19 in HCs) at baseline and post induction treatment were linked with shortened event-free survival (EFS) and overall survival (OS). After adjustment, abnormal PHF19 post induction treatment was independently related to shortened EFS (hazard ratio = 2.474) and OS (hazard ratio = 3.124).

CONCLUSION

PHF19 is aberrantly high and declines post induction therapy, which simultaneously reflects unfavorable treatment response to protease inhibitors as well as shorter EFS and OS in MM patients.

A systematic review on the epidemiology and treatment options of multiple Myeloma in Asia

Multiple myeloma (MM) accounts for almost 15 % of all neoplastic malignancies around the globe. This systematic review intends to analyse data on the treatment and management of MM in selected regions in Asia to identify and prioritize areas that need attention. A comprehensive review of original articles, published in English from 2005 to 2022, derived from the PubMed/MEDLINE database was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. There were 98 studies from select regions of Asia (China, India, Taiwan, Hong Kong, and Singapore) on newly diagnosed MM and relapsed/refractory MM. This review evaluated the trends in disease outcomes with the gradual shift in treatment regimens from doublet to triplet. Additionally, this review also explored autologous stem cell transplant outcome and anti-B-cell maturation antigen (BCMA) chimeric antigen receptor (CAR) T-cell therapy in MM patients. This is the first systematic review attempting to collect data on the utility and comparison of innovative agents and modifications in treatment regimens in the context of the Asian population. This review established that the body of evidence for the management of MM was generally of poor quality and there is a need for more versatile studies in the region. Novel and innovative drug regimens may help in combating the illness but consorted efforts by researchers, industry partners, policymakers, and the government are key factors in the long-term survival of MM patients. In the current systematic review, the authors have tried to give a comprehensive account of the available treatments, trends in MM management and prognosis for MM in Asia.

Characterization of driver mutations identifies gene signatures predictive of prognosis and treatment sensitivity in multiple myeloma

In multiple myeloma (MM), while frequent mutations in driver genes are crucial for disease progression, they traditionally offer limited insights into patient prognosis. This study aims to enhance prognostic understanding in MM by analyzing pathway dysregulations in key cancer driver genes, thereby identifying actionable gene signatures. We conducted a detailed quantification of mutations and pathway dysregulations in 10 frequently mutated cancer driver genes in MM to characterize their comprehensive mutational impacts on the whole transcriptome. This was followed by a systematic survival analysis to identify significant gene signatures with enhanced prognostic value. Our systematic analysis highlighted 2 significant signatures, TP53 and LRP1B, which notably outperformed mere mutation status in prognostic predictions. These gene signatures remained prognostically valuable even when accounting for clinical factors, including cytogenetic abnormalities, the International Staging System (ISS), and its revised version (R-ISS). The LRP1B signature effectively distinguished high-risk patients within low/intermediate-risk categories and correlated with significant changes in the tumor immune microenvironment. Additionally, the LRP1B signature showed a strong association with proteasome inhibitor pathways, notably predicting patient responses to bortezomib and the progression from monoclonal gammopathy of unknown significance to MM. Through a rigorous analysis, this study underscores the potential of specific gene signatures in revolutionizing the prognostic landscape of MM, providing novel clinical insights that could influence future translational oncology research.

Investigation of Non-Coding RNA-Related Autophagy Alterations in Drug-Resistant Multiple Myeloma Plasma Cells

Background & Objective

Multiple myeloma (MM) drug resistance is thought to be caused by the development of protective autophagy. This work aimed to assess the non-coding RNA (ncRNA) autophagy-related alterations in drug-resistant (DR) myeloma cells.

Methods

DR Plasma cells were extracted from the bone marrow of DR patients referred to Baghai 2 Hospital in Ahvaz, Iran. The cells were grown in RPMI-1640 media containing 10% FBS and 1% Pen/Strep and incubated at 37˚C and 5% CO2. After six passages, the plasma cells were precisely isolated and utilized as DR cells. The U266B1 cell line (IBRC C10148) was grown in the RPMI-1640 media containing 10% FBS and 1% Pen/Strep and utilized as drug-sensitive (DS) cells. The relative expression of the genes was determined using the Real-time PCR method. Statistical analysis of the data was performed using GraphPad Prism 8 software.

Results

When the DR cells were compared to the DS cells, there was a notable increase in the expression of ULK1 and LC3B. However, expression of P62 in the DR plasma cells showed a significant decrease compared to the DS plasma cells. The miR-1297 level was considerably higher in the DR cells than in the DS cells. Although, there was no statistically significant difference in the expression of miR-26a-5p between the DS and DR cells. The DR cells exhibited a statistically significant increase in the expression of MALAT1 and SNHG6.

Conclusion

Drug resistance in MM cells may result from overexpression of non-coding RNAs involved in autophagy.

Belantamab mafodotin concentration-QTc relationships in patients with relapsed or refractory multiple myeloma from the DREAMM-1 and -2 studies

AIMS

To evaluate relationships between plasma concentrations of belantamab mafodotin, total monoclonal antibody, and its payload and changes in electrocardiogram (ECG) parameters in patients with relapsed or refractory multiple myeloma from the DREAMM-1 and DREAMM-2 studies.

METHODS

Hysteresis plots and linear regression analyses of pharmacokinetic (PK) analyte (belantamab mafodotin, total monoclonal antibody, and cytotoxic cysteine-maleimidocaproyl monomethyl auristatin F payload) concentrations vs. time-matched ECG parameters (absolute/change from baseline in QT interval corrected for RR interval [QTc/ΔQTc] and QT interval corrected for heart rate by Fridericia's formula [QTcF/ΔQTcF]) were performed. Concentrations of PK analyte required for a 10-ms increase in QTc in DREAMM-2 were calculated via simulation, as was the probability of ΔQTc/ΔQTcF exceeding 10 ms for the expected Cmax of PK analyte concentrations associated with the doses (2.5 and 3.4 mg/kg) administered in DREAMM-2.

RESULTS

Time-matched PK and ECG data from 290 patients (DREAMM-1, n = 73; DREAMM-2, n = 217) were analysed. Hysteresis plots did not clearly indicate any concentration-related prolongation in QTc or QTcF; regression analyses indicated a very small rate of increase in ΔQTc and ΔQTcF with increasing concentrations of PK analytes. Calculated concentrations of PK analyte required for a 10-ms prolongation in QTc were higher than the maximum analyte concentrations observed following treatment with belantamab mafodotin in DREAMM-2; the probability that each dose would prolong ΔQTc and ΔQTcF by >10 ms was 0 and <0.25%, respectively.

CONCLUSION

This study of belantamab mafodotin and its payload did not provide evidence of QT prolongation in patients with relapsed or refractory multiple myeloma at clinically relevant doses.

MiR-34c-5p Inhibition Affects Bax/Bcl2 Expression and Reverses Bortezomib Resistance in Multiple Myeloma Cells

Developing resistance to anticancer drugs complicates the clinical treatment of multiple myeloma patients. Previous studies revealed a link between the unfolded protein response (UPR) and miRNAs with acquired drug resistance. This study aimed to determine the expression profile of XBP1, hsa-miR-34c-5p, hsa-miR-214, and hsa-miR-30c-2* in resistant and sensitive multiple myeloma cell lines to a proteasome inhibitor, bortezomib. After establishing bortezomib-resistant cells, the expression level of XBP1, hsa-miR-214, hsa-miR-34c-5p, and hsa-miR-30c-2* in both cell lines were assessed by qRT-PCR. Hsa-miR-34c-5p was suppressed to study its effect on the expression profile of Bax/Bcl-2. Statistical analysis was done by t-test in two clinically resistant and sensitive cells to bortezomib. MTT assay confirmed the creation of the resistant cell line. The qRT-PCR screening showed a significant difference between XBP1 and miR-34c-5p levels in resistant and sensitive cells. Following hsa-miR-34c-5p blockage, while Bax was overexpressed, Bcl-2 expression was reduced in the resistant cell line, overcoming cells resistant to bortezomib. Our findings demonstrate miR-34c-5p is differentially expressed between bortezomib-sensitive and -resistant MM cells. Inhibiting miR-34c-5p re-sensitized resistant cells to bortezomib by modulating Bax/Bcl-2 expression, suggesting this miRNA regulates apoptosis and drug resistance and may be a promising therapeutic target for overcoming proteasome inhibitor resistance in MM.

Dose reduction and toxicity of lenalidomide-dexamethasone in multiple myeloma: A machine-learning prediction model

PURPOSE

Lenalidomide remains an effective drug for multiple myeloma, but it is often associated with adverse events and requires dose adjustments. The objective of this study was to propose a model for predicting whether a patient would require dose adjustment.

METHODS

This retrospective observational study included patients treated with lenalidomide and dexamethasone from June 2014 to September 2018 at a tertiary hospital. Demographic variables, patient functional status, disease, analytical data specific to myeloma, and treatment-related variables were collected. Univariate and machine learning (logistic regression and classification and regression trees model) analyses were also performed. Kaplan-Meier analysis was used to determine the time of toxicity onset. Only lenalidomide (and not dexamethasone) related dose reductions are included.

RESULTS

A total of 64 patients received lenalidomide-dexamethasone. 69% (44) required dose reduction or discontinuation of treatment due to lenalidomide-related adverse events. The median time between treatment beginning and lenalidomide dose reduction or discontinuation was 8.0 months (95% CI: 6.0-17.0). Age, platelet count, and neutrophil count were related to dose reduction in the univariate model. In the multivariate models, age and neutrophil count were significant in the logistic regression model, renal clearance, and neutrophil count in the classification and regression trees model.

CONCLUSION

Elderly patients and those with low bone marrow reserves are prone to dose-limiting adverse events. This study can aid in making follow-up, prophylaxis, and dosing decisions to achieve better pharmacotherapeutic results.

Proteasome and PARP1 dual-target inhibitor for multiple myeloma: Fluzoparib

One of the current mainstream treatments for multiple myeloma (MM) is chemotherapy. However, due to the high clonal heterogeneity and genomic complexity of MM, single-target drugs have limited efficacy and are prone to drug resistance. Therefore, there is an urgent need to develop multi-target drugs against MM. We screened drugs that simultaneously inhibit poly(ADP-ribose) polymerase 1 (PARP1) and 20S proteasome through computer-aided drug discovery (CADD) techniques, and explored the binding mode and dynamic stability of selected inhibitor to proteasome through Molecular biology (MD) simulation method. Thus, the dual-target inhibition effect of fluzoparib was proposed for the first time, and the ability of dual-target inhibition and tumor killing was explored at the enzyme, cell and animal level, respectively. This provides a theoretical and experimental basis for exploring multi-target inhibitory drugs for cancers.

Different Strategies to Overcome Resistance to Proteasome Inhibitors-A Summary 20 Years after Their Introduction

Proteasome inhibitors (PIs), bortezomib, carfilzomib, and ixazomib, are the first-line treatment for multiple myeloma (MM). They inhibit cytosolic protein degradation in cells, which leads to the accumulation of misfolded and malfunctioned proteins in the cytosol and endoplasmic reticulum, resulting in cell death. Despite being a breakthrough in MM therapy, malignant cells develop resistance to PIs via different mechanisms. Understanding these mechanisms drives research toward new anticancer agents to overcome PI resistance. In this review, we summarize the mechanism of action of PIs and how MM cells adapt to these drugs to develop resistance. Finally, we explore these mechanisms to present strategies to interfere with PI resistance. The strategies include new inhibitors of the ubiquitin-proteasome system, drug efflux inhibitors, autophagy disruption, targeting stress response mechanisms, affecting survival and cell cycle regulators, bone marrow microenvironment modulation, and immunotherapy. We list potential pharmacological targets examined in in vitro, in vivo, and clinical studies. Some of these strategies have already provided clinicians with new anti-MM medications, such as panobinostat and selinexor. We hope that further exploration of the subject will broaden the range of therapeutic options and improve patient outcomes.

Targeting cancer stem cells in multiple myeloma

Multiple myeloma (MM) is a hematological malignancy of bone marrow (BM) plasma cells with excessive clonal expansion and is associated with the overproduction of light-chain or monoclonal immunoglobulins (Igs). MM remains incurable, with high rates of relapses and refractory disease after first-line treatment. Cancer stem cells (CSCs) have been implicated in drug resistance in MM; however, the evidence for CSCs in MM is not adequate, partly due to a lack of uniformity in the definitions of multiple myeloma stem cells (MMSCs). We review advances in understanding MMSCs and their role in drug resistance to MM therapies. We also discuss novel therapeutic strategies to overcome MMSC-mediated relapses and drug resistance.

Isatuximab with pomalidomide-dexamethasone in relapsed/refractory multiple myeloma: post-marketing surveillance in Japan

This post-marketing surveillance assessed the safety and effectiveness of isatuximab plus pomalidomide and dexamethasone (Isa-Pd) for relapsed or refractory multiple myeloma (RRMM) during real-world use in Japan. Data from 211 individuals with RRMM treated with Isa-Pd in Japan between October 2020 and October 2021 were collected, with follow-up for up to 12 months after initiation of Isa-Pd or until treatment discontinuation. The incidence of adverse drug reactions (ADRs), ADRs of special interest (infusion reactions, bone marrow suppression, infections, cardiac disorders, other ADRs of Grade ≥ 3), and serious ADRs was assessed. Best overall response and overall response rate (ORR) were determined. In the safety analysis set (n = 120), ADR incidence was 57.5%. Most ADRs were hematologic, and serious ADRs occurred in 28.3%. Bone marrow suppression occurred in 46.7% of participants (19.2% serious), infusion reactions in 18.3% (6.7% serious), infections in 11.7% (8.3% serious), and a serious cardiac disorder in one participant; other Grade ≥ 3 ADRs were reported in 3.3% (1.7% serious). In the effectiveness analysis set (n = 108), the most common best overall response was very good partial response (24.1%), and ORR was 51.9%. These findings support the safety and effectiveness of Isa-Pd for RRMM in real-life settings in Japan.

A comprehensive review of the PTEN/PI3K/Akt axis in multiple myeloma: From molecular interactions to potential therapeutic targets

Phosphatase and tensin homolog (PTEN), phosphatidylinositol 3-kinase (PI3K), and protein kinase B (Akt) signaling pathways contribute to the development of several cancers, including multiple myeloma (MM). PTEN is a tumor suppressor that influences the PI3K/Akt/mTOR pathway, which in turn impacts vital cellular processes like growth, survival, and treatment resistance. The current study aims to present the role of PTEN and PI3K/Akt/mTOR signaling in the development of MM and its response to treatment. In addition, the molecular interactions in MM that underpin the PI3K/Akt/mTOR pathway and address potential implications for the development of successful treatment plans are also discussed in detail. We investigate their relationship to both upstream and downstream regulators, highlighting new developments in combined therapies that target the PTEN/PI3K/Akt axis to overcome drug resistance, including the use of PI3K and mitogen-activated protein kinase (MAPK) inhibitors. We also emphasize that PTEN/PI3K/Akt pathway elements may be used in MM diagnosis, prognosis, and therapeutic targets.

The function and mechanism of circRNAs in 5-fluorouracil resistance in tumors: Biological mechanisms and future potential

5-Fluorouracil (5-FU) is a well-known chemotherapy drug extensively used in the treatment of breast cancer. It works by inhibiting cancer cell proliferation and inducing cell death through direct incorporation into DNA and RNA via thymidylate synthase (TS). Circular RNAs (circRNAs), a novel family of endogenous non-coding RNAs (ncRNAs) with limited protein-coding potential, contribute to 5-FU resistance. Their identification and targeting are crucial for enhancing chemosensitivity. CircRNAs can regulate tumor formation and invasion by adhering to microRNAs (miRNAs) and interacting with RNA-binding proteins, regulating transcription and translation. MiRNAs can influence enzymes responsible for 5-FU metabolism in cancer cells, affecting their sensitivity or resistance to the drug. In the context of 5-FU resistance, circRNAs can target miRNAs and regulate biological processes such as cell proliferation, cell death, glucose metabolism, hypoxia, epithelial-to-mesenchymal transition (EMT), and drug efflux. This review focuses on the function of circRNAs in 5-FU resistance, discussing the underlying molecular pathways and biological mechanisms. It also presents recent circRNA/miRNA-targeted cancer therapeutic strategies for future clinical application.

The interplay between microRNAs and Nrf2 signaling in human cancers

MicroRNAs (miRNAs), as a class of nonprotein-coding RNAs, post-transcriptionally regulate the expression of target genes by base pairing to 3'-untranslated regions (3'-UTRs). Nuclear factor E2-related factor 2 (Nrf2) has been identified as a critical component of the antioxidant defense mechanism. Dysregulation is associated with chemoresistance and radioresistance in cancerous cells. MiRNA-mediated regulation of the Nrf2 signaling pathway has been shown to have important implications for the development of various cancers. In this article, we review the roles of miRNAs as regulators of the Nrf2 pathway in different human cancers. Ras-associated binding (Rab) proteins have an essential role regulation of vesicle transport, as well as oncogenic functions in preventing chemotherapy efficacy and cancer development. More importantly, increased evidence indicated that the interaction between miRNAs and Rabs has been determined to play critical roles in cancer therapy. However, the significant limitations in using miRNAs for therapeutic applications include cross-targeting and instability of miRNAs. The detailed aspect of the interaction of miRNAs and Rabs is not clearly understood. In the current review, we highlighted the involvement of these molecules as regulators of the Nrf2 pathway in cancer pathogenesis. Potential methods and several obstacles in developing miRNAs as an anticancer therapy are also mentioned.

Preclinical Evaluation of a Novel Series of Polyfluorinated Thalidomide Analogs in Drug-Resistant Multiple Myeloma

Immunomodulatory imide drugs (IMiDs) play a crucial role in the treatment landscape across various stages of multiple myeloma. Despite their evident efficacy, some patients may exhibit primary resistance to IMiD therapy, and acquired resistance commonly arises over time leading to inevitable relapse. It is critical to develop novel therapeutic options to add to the treatment arsenal to overcome IMiD resistance. We designed, synthesized, and screened a new class of polyfluorinated thalidomide analogs and investigated their anti-cancer, anti-angiogenic, and anti-inflammatory activity using in vitro and ex vivo biological assays. We identified four lead compounds that exhibit potent anti-myeloma, anti-angiogenic, anti-inflammatory properties using three-dimensional tumor spheroid models, in vitro tube formation, and ex vivo human saphenous vein angiogenesis assays, as well as the THP-1 inflammatory assay. Western blot analyses investigating the expression of proteins downstream of cereblon (CRBN) reveal that Gu1215, our primary lead candidate, exerts its activity through a CRBN-independent mechanism. Our findings demonstrate that the lead compound Gu1215 is a promising candidate for further preclinical development to overcome intrinsic and acquired IMiD resistance in multiple myeloma.

Real-world treatment patterns and outcomes for patients with multiple myeloma in Denmark, Finland and Sweden: An analysis using linked Nordic registries

AIM

The Health outcomes and Understanding of MyelomA multi-National Study (HUMANS) was a large-scale, retrospective study conducted across Denmark, Finland and Sweden using linked data from national registries. We describe the characteristics, treatment patterns and clinical outcomes for patients with newly diagnosed multiple myeloma (NDMM) over 2010-2018.

METHODS

Patients with NDMM who received MM-specific, first-line treatments, were categorised by treatment (autologous stem cell transplantation [ASCT] or a combination chemotherapy regimen based on bortezomib, lenalidomide or melphalan-prednisolone-thalidomide).

RESULTS

11,023 patients received treatment over 2010-2018. Time between diagnosis and treatment was shortest in Denmark (0.9 months), then Sweden (2.9 months) and Finland (4.6 months). Around one third of patients underwent ASCT. Lenalidomide-based regimens were prescribed to 23-28% of patients in Denmark and Finland, versus 12% in Sweden. Patients receiving lenalidomide had the longest wait for treatment, from 3.2 months (Denmark) to 12.1 months (Sweden). Treatment persistence was highest among patients receiving melphalan-prednisolone-thalidomide (7-8 months) in Finland and Sweden and lowest among those receiving bortezomib (3.5 months) in Finland. Overall survival (OS) was longest among patients with ASCT (7-10 years). Among patients receiving chemotherapy, OS (from diagnosis/treatment initiation), varied between cohorts. In a sensitivity analysis excluding patients with smouldering MM, OS decreased for all; for patients receiving bortezomib or lenalidomide, OS from diagnosis was 40-49 and 27-54 months, respectively.

CONCLUSIONS

This population-based study of patients with NDMM receiving first-line MM-specific treatment, provides real-world data on treatment patterns and outcomes to complement data from randomised clinical trials.

Oncolytic Myxoma virus Increases Autophagy in Multiple Myeloma

Objective

Multiple myeloma, which affects plasma cells, is the second most common hematological malignancy. Despite the development of new drugs and treatment protocols, patient survival has not reached the desired level. In this study, we investigated the effects of Myxoma virus (MYXV), an oncolytic virus, on autophagy in myeloma cells.

Materials and Methods

We analyzed protein expressions of ATG-5, p62, Beclin-1, LC3B, and the apoptosis marker Bcl-2 as autophagy markers in human U-266 and mouse MOPC-315 myeloma cell lines subjected to different doses of MYXV. In addition, autophagic images of myeloma cells were investigated using transmission electron microscopy (TEM).

Results

In the first 24 h, which is the early stage of autophagy, ATG-5 and Beclin-1 expression levels were increased in the U-266 and MOPC-315 cell lines in the groups that had received MYXV at a multiplicity of infection of 15. At 48 h, a significant increase was detected in the expression of LC3B, which is a late indicator. Autophagosomes were observed in myeloma cells by TEM.

Conclusion

MYXV shows an antimyeloma effect by increasing autophagy in myeloma cells.

Protein arginine methyltransferases (PRMTs): Orchestrators of cancer pathogenesis, immunotherapy dynamics, and drug resistance

Protein Arginine Methyltransferases (PRMTs) are a family of enzymes regulating protein arginine methylation, which is a post-translational modification crucial for various cellular processes. Recent studies have highlighted the mechanistic role of PRMTs in cancer pathogenesis, immunotherapy, and drug resistance. PRMTs are involved in diverse oncogenic processes, including cell proliferation, apoptosis, and metastasis. They exert their effects by methylation of histones, transcription factors, and other regulatory proteins, resulting in altered gene expression patterns. PRMT-mediated histone methylation can lead to aberrant chromatin remodeling and epigenetic changes that drive oncogenesis. Additionally, PRMTs can directly interact with key signaling pathways involved in cancer progression, such as the PI3K/Akt and MAPK pathways, thereby modulating cell survival and proliferation. In the context of cancer immunotherapy, PRMTs have emerged as critical regulators of immune responses. They modulate immune checkpoint molecules, including programmed cell death protein 1 (PD-1), through arginine methylation. Drug resistance is a significant challenge in cancer treatment, and PRMTs have been implicated in this phenomenon. PRMTs can contribute to drug resistance through multiple mechanisms, including the epigenetic regulation of drug efflux pumps, altered DNA damage repair, and modulation of cell survival pathways. In conclusion, PRMTs play critical roles in cancer pathogenesis, immunotherapy, and drug resistance. In this overview, we have endeavored to illuminate the mechanistic intricacies of PRMT-mediated processes. Shedding light on these aspects will offer valuable insights into the fundamental biology of cancer and establish PRMTs as promising therapeutic targets.

Preclinical and clinical evaluation of the Janus Kinase inhibitor ruxolitinib in multiple myeloma

Multiple myeloma (MM) is the most common primary malignancy of the bone marrow. No established curative treatment is currently available for patients diagnosed with MM. In recent years, new and more effective drugs have become available for the treatment of this B-cell malignancy. These new drugs have often been evaluated together and in combination with older agents. However, even these novel combinations eventually become ineffective; and, thus, novel therapeutic approaches are necessary to help overcome resistance to these treatments. Recently, the Janus Kinase (JAK) family of tyrosine kinases, specifically JAK1 and JAK2, has been shown to have a role in the pathogenesis of MM. Preclinical studies have demonstrated a role for JAK signaling in direct and indirect growth of MM and downregulation of anti-tumor immune responses in these patients. Also, inhibition of JAK proteins enhances the anti-MM effects of other drugs used to treat MM. These findings have been confirmed in clinical studies which have further demonstrated the safety and efficacy of JAK inhibition as a means to overcome resistance to currently available anti-MM therapies. Additional studies will provide further support for this promising new therapeutic approach for treating patients with MM.

Bone marrow adipocytes is a new player in supporting myeloma cells proliferation and survival in myeloma microenvironment

Multiple myeloma (MM) is a lethal B cell neoplasm characterized by clonal expansion of malignant plasma cells in the bone marrow and remains incurable due to disease relapse and drug resistance. Bone marrow adipocytes (BMAs) are emerging as playing active functions that can support myeloma cell growth and survival. The aim of this study is to investigate myeloma-mesenchymal stem cells (MSCs) interaction and the impact of such interactions on the pathogenesis of MM using in vitro co-culture assay. Here we provide evidence that MM cell up-regulated MSCs to express PPAR-γ and pushes MSCs differentiation toward adipocytes at the expense of osteoblasts in co-culture manner. The increased BMAs can effectively enhance MM cell to proliferation, migration, and chemoresistance via cell-cell contact and/or cytokines release regulated by PPAR-γ signal pathway. This effect was partially reversed in medium containing PPAR-γ antagonist G3335 and indicated that G3335 distorts the maturation of MSC-derived adipocytes and cytokines release by adipocytes through inhibition of PPAR-γ, a key transcriptional factor for the activation of adipogenesis, or cell to cell contact, or both. In meantime, we observed higher expression of adipocyte differentiation associated genes DLK1, DGAT1, FABP4, and FASN both in MSCs and MSC derived adipocytes, but the osteoblast differentiation-associated gene ALP was down regulated in MSCs. These finding mean that direct consequence of MM/MSC interaction that play a role in MM pathogenesis. Consistent with those in vitro results, our primary clinical observation also showed that bone marrow samples from MM patients had significantly higher bone adiposity in comparison with controls and the number of adipocytes decreased in those who were response to anti-MM therapy. Our finding suggested that BMAs may have an important contribution to MM progression, particularly in drugs resistant of MM cells, and plays an important contribution in MM bone disease and treatment failure, but more clinical studies are needed to confirm its role.

Efficacy Analysis of Bortezomib Combined with Lenalidomide in Newly Diagnosed Multiple Myeloma with 1q21 Gain/Amp

OBJECTIVE

1q21 gain/Amp is one of the most common cytogenetic abnormalities. There are controversies about its effects on prognosis and may be associated with inferior outcomes in patients with newly diagnosed multiple myeloma (NDMM). To explore the optimal induction treatment, we analyzed and compared the efficacy of combinations of bortezomib-lenalidomide-dexamethasone (VRD) and only bortezomib-based triplet regimens without lenalidomide (only bortezomib-based) as induction therapy in patients with NDMM with 1q21 gain/Amp.

METHODS

Seventy-six NDMM patients with 1q21 gain/Amp who were admitted to our center from 2016 to 2022 were retrospectively analyzed in this study. The progression and efficacy of the patients were observed.

RESULTS

Within our study group, the overall survival rate stood at 75.0%, and the progression-free survival (PFS) rate reached 40.8% in NDMM patients with 1q21 gain/Amp. The best outcome assessment was that 17.1% achieved complete response (CR) and 44.7% achieved very good partial response (VGPR). Patients in the VRD group had a deeper response (VGPR: 63.6% vs 37.0%, P = 0.034), lower disease progression rate (31.8% vs 70.3%, P = 0.002), longer sustained remission (median 49.7 months vs 18.3 months, P = 0.030), and longer PFS (median 61.9 months vs 22.9 months, P = 0.032) than those treated with only bortezomib-based induction therapy. No significant differences were found among patients with partial response or better (86.4% vs 77.8%, P = 0.532) or CR (27.3% vs 13.0%, P = 0.180). Multivariate analysis showed that only bortezomib-based induction therapy (P = 0.003, HR 0.246, 95% CI 0.097-0.620), International Staging System stage III (P = 0.003, HR 3.844, 95% CI 1.588-9.308) and LMR <3.6 (P = 0.032, HR 0.491, 95% CI 0.257-0.940) were significantly associated with adverse PFS.

CONCLUSIONS

When compared with the sequential administration of bortezomib and lenalidomide or only bortezomib-based protocols, NDMM patients with 1q21 gain/Amp may benefit more from VRD as initial treatments.

Lenalidomide use in multiple myeloma (Review)

Lenalidomide is a second-generation new immunomodulatory medication used to treat multiple myeloma (MM). Its mechanism of action involves affecting the expression of vascular endothelial growth factor, interleukin-6, cytochrome c, caspase-8, as well as other factors including immunological modulation and the direct killing of cells, among others, rendering it a fundamental medication, useful for the treatment of MM. Combining lenalidomide with other medications such dexamethasone, bortezomib, ixazomib, carfilzomib and daratumumab can markedly alleviate MM. When autologous-hematopoietic stem cell transplantation (ASCT) cannot be utilized to treat newly diagnosed individuals with MM (NDMM), monotherapy maintenance following lenalidomide and dexamethasone may be employed. Following ASCT, single-agent maintenance with lenalidomide can be performed as an additional treatment. The combination of bortezomib and lenalidomide has been demonstrated to be associated with favorable response rates, tolerable toxicity, and therapeutic benefits although caution is warranted to prevent the onset of peripheral neuropathy with its use. A new-generation oral drug with an excellent safety profile, ixazomib, is more practical and therapeutically applicable in relapsed refractory MM. However, the frequent occurrence of cardiovascular events, hematocrit, and infections with it require flexible adjustment in its clinical application. Carfilzomib produces a rapid and profound response in patients with NDMM eligible for transplantation, but its cardiovascular side effects need to be closely monitored. The primary aim of the present review was to examine the pharmacological properties and pharmacokinetics of lenalidomide, as well as the efficacy and safety of lenalidomide-based treatments with reference to data from clinical trials and real-world studies.

Autophagy-related mechanisms for treatment of multiple myeloma

Multiple myeloma (MM) is a type of hematological cancer that occurs when B cells become malignant. Various drugs such as proteasome inhibitors, immunomodulators, and compounds that cause DNA damage can be used in the treatment of MM. Autophagy, a type 2 cell death mechanism, plays a crucial role in determining the fate of B cells, either promoting their survival or inducing cell death. Therefore, autophagy can either facilitate the progression or hinder the treatment of MM disease. In this review, autophagy mechanisms that may be effective in MM cells were covered and evaluated within the contexts of unfolded protein response (UPR), bone marrow microenvironment (BMME), drug resistance, hypoxia, DNA repair and transcriptional regulation, and apoptosis. The genes that are effective in each mechanism and research efforts on this subject were discussed in detail. Signaling pathways targeted by new drugs to benefit from autophagy in MM disease were covered. The efficacy of drugs that regulate autophagy in MM was examined, and clinical trials on this subject were included. Consequently, among the autophagy mechanisms that are effective in MM, the most suitable ones to be used in the treatment were expressed. The importance of 3D models and microfluidic systems for the discovery of new drugs for autophagy and personalized treatment was emphasized. Ultimately, this review aims to provide a comprehensive overview of MM disease, encompassing autophagy mechanisms, drugs, clinical studies, and further studies.

Methylcrotonyl-CoA carboxylase subunit 1 (MCCA) regulates multidrug resistance in multiple myeloma

AIMS

This study aimed to investigate the effect and mechanism of methylcrotonyl-CoA carboxylase subunit 1 (MCCA) on multidrug resistance in multiple myeloma (MM).

MATERIALS AND METHODS

The apoptosis kit and CCK-8 reagent were used to detect drug-induced cell apoptosis and viability. Immunoprecipitation, immunofluorescence staining, and protein structural simulation were used to detect the interaction between MCCA and Bad. Immunodeficient mice were injected with ARD cells and treated with bortezomib. Changes in tumor burden were recorded by bioluminescence imaging, and κ light chain content in the blood of mice was detected by enzyme-linked immunoassay.

KEY FINDINGS

Patients with high MCCA expression from a primary MM dataset had superior overall survival. After treatment with different anti-MM drugs, MCCA knockdown MM (MCCA-KD) cells had higher survival rates than control knockdown (CTR-KD) cells (p < 0.05). Mechanistic studies have revealed that MCCA-KD cells had dysfunctional mitochondria with decreased Bax and Bad levels and increased Bcl-xl and Mcl-1 levels. Furthermore, that MCCA and Bad demonstrated protein-protein interactions. The half-life of Bad in MCCA-KD cells is significantly shorter than that in CTR-KD cells (7.34 vs. 2.42 h, p < 0.05). In a human MM xenograft mouse model, we confirmed that MCCA-KD tumors had a poor response to anti-MM drugs in vivo. Finally, we showed that MCCA might contribute to multidrug resistance in different human cancers, particularly in solid tumors.

SIGNIFICANCE

Our findings demonstrated a novel function of MCCA in multidrug resistance. The lack of MCCA expression promoted antiapoptotic cell signaling in MM cells.

Inflammatory Bone Marrow Mesenchymal Stem Cells in Multiple Myeloma: Transcriptional Signature and In Vitro Modeling

Bone marrow mesenchymal stem cells (BM MSCs) play a tumor-supportive role in promoting drug resistance and disease relapse in multiple myeloma (MM). Recent studies have discovered a sub-population of MSCs, known as inflammatory MSCs (iMSCs), exclusive to the MM BM microenvironment and implicated in drug resistance. Through a sophisticated analysis of public expression data from unexpanded BM MSCs, we uncovered a positive association between iMSC signature expression and minimal residual disease. While in vitro expansion generally results in the loss of the iMSC signature, our meta-analysis of additional public expression data demonstrated that cytokine stimulation, including IL1-β and TNF-α, as well as immune cells such as neutrophils, macrophages, and MM cells, can reactivate the signature expression of iMSCs to varying extents. These findings underscore the importance and potential utility of cytokine stimulation in mimicking the gene expression signature of early passage of iMSCs for functional characterizations of their tumor-supportive roles in MM.

METTL3 facilitates multiple myeloma tumorigenesis by enhancing YY1 stability and pri-microRNA-27 maturation in m6A-dependent manner

Multiple myeloma (MM) is a pernicious plasma cell disorder and has a poor prognosis. N6-methyladenosine (m6A) is an abundant epigenetic RNA modification and is important in cancer progression. Nevertheless, the function of m6A and its regulator METTL3 in MM are rarely reported. Here, we identified the m6A "writers", METTL3, was enhanced in MM and found that Yin Yang 1 (YY1) and primary-miR-27a-3p were the potential target for METTL3. METTL3 promoted primary-miR-27a-3p maturation and YY1 mRNA stability in an m6A manner. YY1 also was found to facilitate miR-27a-3p transcription. METTL3 affected the growth, apoptosis, and stemness of MM cells through accelerating the stability of YY1 mRNA and the maturation of primary-miR-27a-3p in vitro and in vivo. Our results reveal the key function of the METTL3/YY1/miR-27a-3p axis in MM and may provide fresh insights into MM therapy.

Immunomodulatory Effect of Proteasome Inhibitors via the Induction of Immunogenic Cell Death in Myeloma Cells

Several anti-cancer drugs are known to have immunomodulatory effects, including immunogenic cell death (ICD) of cancer cells. ICD is a form of apoptosis which is caused by the release of damage-associated molecular patterns (DAMPs), the uptake of cancer antigens by dendritic cells, and the activation of acquired immunity against cancer cells. ICD was originally reported in solid tumors, and there have been few reports on ICD in multiple myeloma (MM). Here, we showed that proteasome inhibitors, including carfilzomib, induce ICD in myeloma cells via an unfolded protein response pathway distinct from that in solid tumors. Additionally, we demonstrated the potential impact of ICD on the survival of patients with myeloma. ICD induced by proteasome inhibitors is expected to improve the prognosis of MM patients not only by its cytotoxic effects, but also by building strong immune memory response against MM cells in combination with other therapies, such as chimeric antigen receptor-T cell therapy.

Extracellular vesicles derived from immortalized human natural killer cell line NK3.3 as a novel therapeutic for multiple myeloma

Introduction

Over the last decade, there have been many advancements in the therapeutic treatment of multiple myeloma (MM), including the use of natural killer (NK) cells. However, despite promising results from clinical trials, there are concerns over the use of NK cell-based therapy. Cells often undergo growth arrest, limiting their experimental utility; donor cells are extremely heterogeneous, resulting in content variability; and patients receiving allogeneic cells are at risk for graft-versus-host disease and/or cytokine release syndrome. Extracellular vesicles (EVs) have emerged as a new natural therapeutic tool. EVs are known to carry cargo derived from the parent cell from which they originate. NK cells play an important role in the innate immune system, targeting and killing tumor cells. This has led many researchers to isolate EVs from NK cells for their cytotoxic potential.

Methods

In this study, we isolated EVs from the NK cell line, NK3.3, which was derived from the peripheral blood of a healthy donor. Currently, it is the only normal human NK cell line reported with all the functional characteristics of healthy NK cells. To address the issue of growth arrest, we immortalized NK3.3 cells with lentivirus encoding the catalytic subunit of human telomerase htert (NK3.3-LTV). EVs from these cells were isolated using a modified polyethylene glycol (PEG)-acetate precipitation protocol to simplify processing and increase EV yield.

Results and conclusions

We demonstrated that NK3.3-LTV EVs target both sensitive and drug-resistant MM cell lines as well as primary patient MM cells in vitro, decreasing proliferation and inducing apoptotic cell death as well as or better than EVs from non-immortalized cells with no toxicity towards normal cells. This study is the first step towards developing an immunotherapeutic product designed to treat patients with relapsed/refractory MM.

Differential Diagnosis and Therapeutic Advances in Multiple Myeloma: A Review Article

Multiple myeloma (MM) is a hematologic malignancy characterized by the abnormal clonal proliferation of plasma cells that may result in focal bone lesions, renal failure, anemia, and/or hypercalcemia. Recently, the diagnosis and treatment of MM have evolved due to a better understanding of disease pathophysiology, improved risk stratification, and new treatments. The incorporation of new drugs, including proteasome inhibitors, immunomodulatory drugs, anti-CD38 antibodies and high-dose chemotherapy followed by hematopoietic stem cell transplantation, has resulted in a significant improvement in patient outcomes and QoL. In this review, we summarize differential diagnoses and therapeutic advances in MM.

Integrative analysis of the prognostic value and immune microenvironment of mitophagy-related signature for multiple myeloma

BACKGROUND

Multiple myeloma (MM) is a fatal malignant tumor in hematology. Mitophagy plays vital roles in the pathogenesis and drug sensitivity of MM.

METHODS

We acquired transcriptomic expression data and clinical index of MM patients from NCI public database, and 36 genes involved in mitophagy from the gene set enrichment analysis (GSEA) database. Least absolute shrinkage and selection operator (LASSO) Cox regression analysis was conducted to construct a risk score prognostic model. Kaplan-Meier survival analysis and receiver operation characteristic curves (ROC) were conducted to identify the efficiency of prognosis and diagnosis. ESTIMATE algorithm and immune-related single-sample gene set enrichment analysis (ssGSEA) was performed to uncover the level of immune infiltration. QRT-PCR was performed to verify gene expression in clinical samples of MM patients. The sensitivity to chemotherapy drugs was evaluated upon the database of the genomics of drug sensitivity in cancer (GDSC).

RESULTS

Fifty mitophagy-related genes were differently expressed in two independent cohorts. Ten out of these genes were identified to be related to MM overall survival (OS) rate. A prognostic risk signature model was built upon on these genes: VDAC1, PINK1, VPS13C, ATG13, and HUWE1, which predicted the survival of MM accurately and stably both in training and validation cohorts. MM patients suffered more adverse prognosis showed more higher risk core. In addition, the risk score was considered as an independent prognostic element for OS of MM patients by multivariate cox regression analysis. Functional pathway enrichment analysis of differentially expressed genes (DEGs) based on risk score showed terms of cell cycle, immune response, mTOR pathway, and MYC targets were obviously enriched. Furthermore, MM patients with higher risk score were observed lower immune scores and lower immune infiltration levels. The results of qRT-PCR verified VDAC1, PINK1, and HUWE1 were dysregulated in new diagnosed MM patients. Finally, further analysis indicated MM patients showed more susceptive to bortezomib, lenalidomide and rapamycin in high-risk group.

CONCLUSION

Our research provided a neoteric prognostic model of MM based on mitophagy genes. The immune infiltration level based on risk score paved a better understanding of the participation of mitophagy in MM.

Safety and efficacy of T-cell-redirecting bispecific antibodies for patients with multiple myeloma: a systematic review and meta-analysis

BACKGROUND

In recent years, several bispecific antibodies (BsAbs) have been introduced that revolutionized the treatment approach for patients with multiple myeloma (MM). In the present study, we sought for conducting a systematic review and meta-analysis with the aim of evaluating the safety and efficacy of BsAbs in MM patients.

METHODS

PubMed, Scopus, Web of Science, and Embase databases were systematically searched on June 10, 2022. Two steps of title/abstract and full-text screening were performed for selecting the relevant articles. The primary endpoint was considered to evaluate the safety of BsAbs by examining the rate of hematologic and non-hematologic adverse effects (AEs). The secondary outcome was set at the efficacy of BsAbs through pooling objective response rate (ORR), (stringent) complete response (sCR/CR), very good partial response (VGPR), and partial response (PR).

RESULTS

Eleven publications with a total of nine evaluable BsAbs were included for qualitative and quantitative data synthesis. Hematologic AEs were more common among patients than non-hematologic events, with the most frequent events being anemia (41.4%), neutropenia (36.4%), and thrombocytopenia (26.3%). The most common non-hematological AE was infection, which occurred in 39.9% of patients, followed by dysgeusia (28.3%), fatigue (26.5%), and diarrhea (25.8%). Besides, 8.1% of patients experienced immune effector cell-associated neurotoxicity syndrome and neurotoxicity occurred in 5.1% of them. Moreover, 59.8% of patients experienced cytokine release syndrome. The pooled rate of deaths attributable to BsAbs was estimated at 0.1%. In terms of efficacy measures, the ORR was achieved in 62.6% of MM patients, and the pooled rates of sCR/CR, VGPR, and PR were 22.7%, 23.0%, and 12.1%, respectively.

CONCLUSIONS

In an era with several emerging promising treatments for MM, BsAbs have achieved a high ORR and tolerable AEs in heavily pretreated patients. However, there is still room for developing BsAbs with a lower rate of AEs and capable of bypassing tumor evasion mechanisms.

Machine Learning Approach for Rapid, Accurate Point-of-Care Prediction of M-Spike Values in Multiple Myeloma

PURPOSE

The gold standard for monitoring response status in patients with multiple myeloma (MM) is serum and urine protein electrophoresis which quantify M-spike proteins; however, the turnaround time for results is 3-7 days which delays treatment decisions. We hypothesized that machine learning (ML) could integrate readily available clinical and laboratory data to rapidly and accurately predict patient M-spike values.

METHODS

A retrospective chart review was performed using the deidentified, electronic medical records of 171 patients with MM.

RESULTS

Random forest (RF) analysis identified the weighted value of each independent variable (N = 43) integrated into the ML algorithm. Pearson and Spearman coefficients indicated that the ML-predicted M-spike values correlated highly with laboratory-measured serum protein electrophoresis values. Feature selected RF modeling revealed that only two variables-the first lagged M-spike and serum total protein-accurately predicted the M-spike.

CONCLUSION

Taken together, our results demonstrate the feasibility and prognostic potential of ML tools that integrate electronic data to longitudinally monitor disease burden. ML tools support the seamless, secure exchange of patient information to expedite and personalize clinical decision making and overcome geographic, financial, and social barriers that currently limit the access of underserved populations to cancer care specialists so that the benefits of medical progress are not limited to selected groups.

Unlocking Drug Resistance in Multiple Myeloma: Adipocytes as Modulators of Treatment Response

Multiple myeloma (MM) is an incurable hematological malignancy characterized by the clonal proliferation of malignant plasma cells. Despite the development of a diverse array of targeted drug therapies over the last decade, patients often relapse and develop refractory disease due to multidrug resistance. Obesity is a growing public health threat and a risk factor for multiple myeloma, although the mechanisms by which obesity contributes to MM growth and progression have not been fully elucidated. In the present study, we evaluated whether crosstalk between adipocytes and MM cells promoted drug resistance and whether this was amplified by obesity. Human adipose-derived stem cells (ASCs) from nineteen normal (BMI = 20-25 kg/m2), overweight (25-30 kg/m2), or obese (30-35 kg/m2) patients undergoing elective liposuction were utilized. Cells were differentiated into adipocytes, co-cultured with RPMI 8226 or U266B1 multiple myeloma cell lines, and treated with standard MM therapies, including bortezomib or a triple combination of bortezomib, dexamethasone, and lenalidomide. We found that adipocytes from overweight and obese individuals increased cell adhesion-mediated drug resistance (CAM-DR) survival signals in MM cells, and P-glycoprotein (P-gp) and multidrug resistance-associated protein (MRP) drug transporter expression. Further, co-culture enhanced in vitro angiogenesis, MMP-2 activity, and protected MM cells from drug-induced decreases in viability. In summary, we provide an underlying mechanism by which obesity can impair the drug response to MM and allow for recurrence and/or disease progression.

In Silico, In Vitro, and In Vivo Investigations on Adapalene as Repurposed Third Generation Retinoid against Multiple Myeloma and Leukemia

The majority of hematopoietic cancers in adults are incurable and exhibit unpredictable remitting-relapsing patterns in response to various therapies. The proto-oncogene c-MYC has been associated with tumorigenesis, especially in hematological neoplasms. Therefore, targeting c-MYC is crucial to find effective, novel treatments for blood malignancies. To date, there are no clinically approved c-MYC inhibitors. In this study, we virtually screened 1578 Food and Drug Administration (FDA)-approved drugs from the ZINC15 database against c-MYC. The top 117 compounds from PyRx-based screening with the best binding affinities to c-MYC were subjected to molecular docking studies with AutoDock 4.2.6. Retinoids consist of synthetic and natural vitamin A derivatives. All-trans-retinoic acid (ATRA) were highly effective in hematological malignancies. In this study, adapalene, a third-generation retinoid usually used to treat acne vulgaris, was selected as a potent c-MYC inhibitor as it robustly bound to c-MYC with a lowest binding energy (LBE) of -7.27 kcal/mol, a predicted inhibition constant (pKi) of 4.69 µM, and a dissociation constant (Kd value) of 3.05 µM. Thus, we examined its impact on multiple myeloma (MM) cells in vitro and evaluated its efficiency in vivo using a xenograft tumor zebrafish model. We demonstrated that adapalene exerted substantial cytotoxicity against a panel of nine MM and two leukemic cell lines, with AMO1 cells being the most susceptible one (IC50 = 1.76 ± 0.39 µM) and, hence, the focus of this work. Adapalene (0.5 × IC50, 1 × IC50, 2 × IC50) decreased c-MYC expression and transcriptional activity in AMO1 cells in a dose-dependent manner. An examination of the cell cycle revealed that adapalene halted the cells in the G2/M phase and increased the portion of cells in the sub-G0/G1 phase after 48 and 72 h, indicating that cells failed to initiate mitosis, and consequently, cell death was triggered. Adapalene also increased the number of p-H3(Ser10) positive AMO1 cells, which is a further proof of its ability to prevent mitotic exit. Confocal imaging demonstrated that adapalene destroyed the tubulin network of U2OS cells stably transfected with a cDNA coding for α-tubulin-GFP, refraining the migration of malignant cells. Furthermore, adapalene induced DNA damage in AMO1 cells. It also induced apoptosis and autophagy, as demonstrated by flow cytometry and western blotting. Finally, adapalene impeded tumor growth in a xenograft tumor zebrafish model. In summary, the discovery of the vitamin A derivative adapalene as a c-MYC inhibitor reveals its potential as an avant-garde treatment for MM.