Circulating microRNA expressions can predict the outcome of lenalidomide plus low-dose dexamethasone treatment in patients with refractory/relapsed multiple myeloma

Circulating miR-16 and miR-21 Levels in Multiple Myeloma: Prognostic Significance of Survival and Response to Lenalidomide Treatment

MicroRNAs (miRNAs), particularly miR-16 and miR-21, play a crucial role in multiple myeloma (MM) pathogenesis by regulating gene expression. This study evaluated the prognostic significance of circulating miR-16 and miR-21 expression levels in 48 patients with MM at diagnosis treated with lenalidomide-dexamethasone (LD) compared with 15 healthy individuals (HI). All patients were treated with LD, 13 at first line and 35 at relapse, of whom 21 were tested twice at diagnosis and before LD initiation. The results revealed significantly lower levels of miR-16 and miR-21 in patients than in HIs, both at diagnosis and relapse, with decreased miR-16 levels at diagnosis, indicating improved overall survival (OS) (p value 0.024). Furthermore, miR-16 and miR-21 levels were associated with disease markers, while both correlated with the depth of response and mir-16 with sustained response to LD treatment. Ratios of both miR-16 and miR-21 expression levels (prior to LD treatment/diagnosis) below two predicted a shorter time to response (p = 0.027) and a longer time to next treatment (p = 0.042), respectively. These findings suggested a prognostic value for serum miR-16 and miR-21 levels in MM, as their expression levels correlated with disease variables and treatment outcomes.

miRNAs and Multiple Myeloma: Focus on the Pathogenesis, Prognosis, and Drug Resistance

Multiple myeloma (MM) produces clonal plasma cells and aberrant monoclonal antibody accumulation in patients' bone marrow (BM). Around 1% of all cancers and 13% of hematological malignancies are caused by MM, making it one of the most common types of cancer. Diagnostic and therapeutic methods for managing MM are currently undergoing extensive research. MicroRNAs (miRNAs) are short noncoding RNAs that reduce or inhibit the translation of their target mRNA after transcription. Because miRNAs play an influential role in how myeloma develops, resources, and becomes resistant to drugs, miRNA signatures may be used to diagnose, do prognosis, and treat the myeloma response. Consequently, researchers have investigated the levels of miRNA in plasma cells from MM patients and developed tools to test whether they directly impacted tumor growth. This review discusses the latest discoveries in miRNA science and their role in the development of MM. We also emphasize the potential applications of miRNAs to diagnose, prognosticate, and treat MM in the future.

Involvement of Small Non-Coding RNA and Cell Antigens in Pathogenesis of Extramedullary Multiple Myeloma

Extramedullary multiple myeloma (EMD) is an aggressive disease; malignant plasma cells lose their dependence in the bone marrow microenvironment and migrate into tissues. EMD is a negative prognostic factor of survival. Using flow cytometry and next-generation sequencing, we aimed to identify antigens and microRNAs (miRNAs) involved in EMD pathogenesis. Flow cytometry analysis revealed significant differences in the level of clonal plasma cells between MM and EMD patients, while the expression of CD markers was comparable between these two groups. Further, miR-26a-5p and miR-30e-5p were found to be significantly down-regulated in EMD compared to MM. Based on the expression of miR-26a-5p, we were able to distinguish these two groups of patients with high sensitivity and specificity. In addition, the involvement of deregulated miRNAs in cell cycle regulation, ubiquitin-mediated proteolysis and signaling pathways associated with infections or neurological disorders was observed using GO and KEGG pathways enrichment analysis. Subsequently, a correlation between the expression of analyzed miRNAs and the levels of CD molecules was observed. Finally, clinicopathological characteristics as well as CD antigens associated with the prognosis of MM and EMD patients were identified. Altogether, we identified several molecules possibly involved in the transformation of MM into EMD.

Association of DNA repair genes polymorphisms with childhood acute lymphoblastic leukemia: a high-resolution melting analysis

Objective

Acute lymphoblastic leukemia (ALL) is one of the most common cancers in children for which the exact pathogenesis is not yet known. Single-nucleotide variants (SNVs) in different DNA repair genes are reported to be associated with ALL risk. This study aimed to determine the association between XRCC1 (rs1799782) and NBN (rs1805794, rs709816) SNVs and childhood ALL risk in a sample of the Iranian population. Fifty children with ALL and 50 age- and sex-matched healthy children were included in this case–control study. Genotyping of the mentioned SNVs was done by high-resolution melting (HRM) analysis.

Results

The prevalence of all three SNVs in XRCC1 and NBN genes did not differ between the patient and control groups, and these polymorphisms were not associated with childhood ALL risk (P > 0.05). HRM was a practical method for the detection of SNVs in XRCC1 and NBN genes. We found no significant association between XRCC1 (rs1799782) and NBN (rs1805794, rs709816) SNVs and childhood ALL risk.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13104-022-05918-3.

Liquid biopsy: an evolving paradigm for the biological characterisation of plasma cell disorders

Liquid biopsies-a source of circulating cell-free nucleic acids, proteins and extracellular vesicles-are currently being explored for the quantitative and qualitative characterisation of the tumour genome and as a mode of non-invasive therapeutic monitoring in cancer. Emerging data suggest that liquid biopsies might offer a potentially simple, non-invasive, repeatable strategy for diagnosis, prognostication and therapeutic decision making in a genetically heterogeneous disease like multiple myeloma (MM), with particular applicability in subsets of patients where conventional markers of disease burden may be less informative. In this review, we describe the emerging utility of the evaluation of circulating tumour DNA, extracellular RNA, cell-free proteins and metabolites and extracellular vesicles in MM.

miR-22 Modulates Lenalidomide Activity by Counteracting MYC Addiction in Multiple Myeloma

Simple Summary

MYC-driven deregulation of microRNAs represents a critical event in human malignancies, including multiple myeloma (MM). Although the introduction of new therapeutic strategies has prolonged survival of patients, MM remains an incurable disease, often due to the onset of drug resistance. MYC hyperactivation is involved in the development of resistance to immunomodulatory imide drugs (IMiDs), but the mechanism is still unclear. Here, we report that MYC represses the transcription of tumor suppressor miR-22 in MM, and that low miR-22 expression is associated with IMiD resistance in MM patients. By in silico and in vitro analysis, we show that miR-22 mimics affect MYC signaling, leading to MM cell death in MYC proficient cells. Furthermore, we demonstrate here that lenalidomide treatment enhances miR-22 activity by reducing the MYC inhibitory effect, and that the combination of lenalidomide with miR-22 mimics restores drug sensitivity, leading to synergistic anti-MM activity.

Abstract

Background: MYC is a master regulator of multiple myeloma (MM) by orchestrating several pro-tumoral pathways, including reprograming of the miRNA transcriptome. MYC is also involved in the acquirement of resistance to anti-MM drugs, including immunomodulatory imide drugs (IMiDs). Methods: In silico analysis was performed on MM proprietary and on public MMRF-CoMMpass datasets. Western blot and chromatin immunoprecipitation (ChIP) experiments were performed to validate miR-22 repression induced by MYC. Cell viability and apoptosis assays were used to evaluate lenalidomide sensitization after miR-22 overexpression. Results: We found an inverse correlation between MYC and miR-22 expression, which is associated with poor outcome in IMiD-treated MM patients. Mechanistically, we showed that MYC represses transcription of miR-22, which, in turn, targets MYC, thus establishing a feed-forward loop. Interestingly, we found that IMiD lenalidomide increases miR-22 expression by reducing MYC repression and, most importantly, that the combination of lenalidomide with miR-22 mimics results in a synergistic direct and NK-mediated cytotoxic activity. Conclusions: Taken together, our findings indicate that: (1) low miR-22 expression could represent a potential predictive biomarker of poor lenalidomide response in MM patients; and (2) miR-22 reduces MYC oncogenic activity, thus triggering a novel synthetic lethality loop, which sensitizes MM cells to lenalidomide.

Circulating miRNAs as Auxiliary Diagnostic Biomarkers for Multiple Myeloma: A Systematic Review, Meta-Analysis, and Recommendations

Multiple myeloma (MM) is a hematologic malignancy characterized by aberrant expansion of monoclonal plasma cells with high mortality and severe complications due to the lack of early diagnosis and timely treatment. Circulating miRNAs have shown potential in the diagnosis of MM with inconsistent results, which remains to be fully assessed. Here we updated a meta-analysis with relative studies and essays published in English before Jan 31, 2021. After steps of screening, 32 studies from 11 articles that included a total of 627 MM patients and 314 healthy controls were collected. All data were analyzed by REVMAN 5.3 and Stata MP 16, and the quality of included literatures was estimated by Diagnostic Accuracy Study 2 (QUADAS-2). The pooled area under the curve (AUC) shown in summary receiver operating characteristic (SROC) analyses of circulating miRNAs was 0.87 (95%CI, 0.81–0.89), and the sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were 0.79, 0.86, 5, 0.27, 22, respectively. Meta-regression and subgroup analysis exhibited that “miRNA cluster”, patient “detailed stage or Ig isotype” accounted for a considerable proportion of heterogeneity, revealing the importance of study design and patient inclusion in diagnostic trials; thus standardized recommendations were proposed for further studies. In addition, the performance of the circulating miRNAs included in MM prognosis and treatment response prediction was summarized, indicating that they could serve as valuable biomarkers, which would expand their clinical application greatly.

miRNAs mediated drug resistance in hematological malignancies

Despite improvements in the therapeutic approaches for hematological malignancies in the last decades, refractory disease still occurs, and cancer drug resistance still remains a major hurdle in the clinical management of these cancer patients. The investigation of this problem has been extensive and different mechanism and molecules have been associated with drug resistance. MicroRNAs (miRNAs) have been described as having an important action in the emergence of cancer, including hematological tumors, and as being major players in their progression, aggressiveness and response to treatments. Moreover, miRNAs have been strongly associated with cancer drug resistance and with the modulation of the sensitivity of cancer cells to a wide array of anticancer drugs. Furthermore, this role has also been reported for miRNAs packaged into extracellular vesicles (EVs-miRNAs), which in turn have been described as essential for the horizontal transfer of drug resistance to sensitive cells. Several studies have been suggesting the use of miRNAs as biomarkers for drug response and clinical outcome prediction, as well as promising therapeutic tools in hematological diseases. Indeed, the combination of miRNA-based therapeutic tools with conventional drugs contributes to overcome drug resistance. This review addresses the role of miRNAs in the pathogenesis of hematological malignances, namely multiple myeloma, leukemias and lymphomas, highlighting their important action (either in their cell-free circulating form or within circulating EVs) in drug resistance and their potential clinical applications.

Targeting microRNA in hematologic malignancies

PURPOSE OF REVIEW

MiRNAs are critical regulators for gene expression. Numerous studies have revealed how miRNAs contribute to the pathogenesis of hematologic malignancies.

RECENT FINDINGS

The identification of novel miRNA regulatory factors and pathways crucial for miRNA dysregulation has been linked to hematologic malignancies. miRNA expression profiling has shown their potential to predict outcomes and treatment responses. Recently, targeting miRNA biogenesis or pathways has become a promising therapeutic strategy with recent miRNA-therapeutics being developed.

SUMMARY

We provide a comprehensive overview of the role of miRNAs for diagnosis, prognosis, and therapeutic potential in hematologic malignancies.

Emerging Insights on the Biological Impact of Extracellular Vesicle-Associated ncRNAs in Multiple Myeloma

Increasing evidence indicates that extracellular vesicles (EVs) released from both tumor cells and the cells of the bone marrow microenvironment contribute to the pathobiology of multiple myeloma (MM). Recent studies on the mechanisms by which EVs exert their biological activity have indicated that the non-coding RNA (ncRNA) cargo is key in mediating their effect on MM development and progression. In this review, we will first discuss the role of EV-associated ncRNAs in different aspects of MM pathobiology, including proliferation, angiogenesis, bone disease development, and drug resistance. Finally, since ncRNAs carried by MM vesicles have also emerged as a promising tool for early diagnosis and therapy response prediction, we will report evidence of their potential use as clinical biomarkers.

Liquid biopsies for multiple myeloma in a time of precision medicine

Multiple myeloma (MM) is a challenging, progressive, and highly heterogeneous hematological malignancy. MM is characterized by multifocal proliferation of neoplastic plasma cells in the bone marrow (BM) and sometimes in extramedullary organs. Despite the availability of novel drugs and the longer median overall survival, some patients survive more than 10 years while others die rapidly. This heterogeneity is mainly driven by biological characteristics of MM cells, including genetic abnormalities. Disease progressions are mainly due to the inability of drugs to overcome refractory disease and inevitable drug-resistant relapse. In clinical practice, a bone marrow biopsy, mostly performed in one site, is still used to access the genetics of MM. However, BM biopsy use is limited by its invasive nature and by often not accurately reflecting the mutational profile of MM. Recent insights into the genetic landscape of MM provide a valuable opportunity to implement precision medicine approaches aiming to enable better patient profiling and selection of targeted therapies. In this review, we explore the use of the emerging field of liquid biopsies in myeloma patients considering current unmet medical needs, such as assessing the dynamic mutational landscape of myeloma, early predictors of treatment response, and a less invasive response monitoring.

The power of microRNAs as diagnostic and prognostic biomarkers in liquid biopsies

In the last decades, progresses in medical oncology have ameliorated the treatment of patients and their outcome. However, further improvements are still necessary, in particular for certain types of tumors such as pancreatic, gastric, and lung cancer as well as acute myeloid leukemia where early detection and monitoring of the disease are crucial for final patient outcome. Liquid biopsy represents a great advance in the field because it is less invasive, less time-consuming, and safer compared to classical biopsies and it can be useful to monitor the evolution of the disease as well as the response of patients to therapy. Liquid biopsy allows the detection of circulating tumor cells, nucleic acids, and exosomes not only in blood but also in different biological fluids: urine, saliva, pleural effusions, cerebrospinal fluid, and stool. Among the potential biomarkers detectable in liquid biopsies, microRNAs (miRNAs) are gaining more and more attention, since they are easily detectable, quite stable in biological fluids, and show high sensitivity. Many data demonstrate that miRNAs alone or in combination with other biomarkers could improve the diagnostic and prognostic power for many different tumors. Despite this, standardization of methods, sample preparation, and analysis remain challenging and a huge effort should be made to address these issues before miRNA biomarkers can enter the clinic. This review summarizes the main findings in the field of circulating miRNAs in both solid and hematological tumors.

Predictive impact of circulating microRNA-193a-5p on early relapse after autologous stem cell transplantation in patients with multiple myeloma

We explored prognostic roles of circulating microRNAs (miRs) in multiple myeloma (MM) treated with autologous stem cell transplantation (ASCT) following induction chemotherapy. In part I of the study (n = 40), we identified a decreasing dynamics of circulating miR-193a-5p expression from diagnosis to pre-ASCT. In patients who experienced early relapse within one year post ASCT (n = 9) these patterns were distinctive compared to those without early relapse in a 1:2 matched cohort (n = 18). In part II (n = 90), multivariate analyses showed that the International Staging System score and miR-193a-5p expression before ASCT were independent prognostic factors. Conclusively, expression of circulating miR-193a-5p before ASCT could be a prognostic biomarker for transplant-eligible MM.

The Non-Coding RNA Landscape of Plasma Cell Dyscrasias

Despite substantial advancements have been done in the understanding of the pathogenesis of plasma cell (PC) disorders, these malignancies remain hard-to-treat. The discovery and subsequent characterization of non-coding transcripts, which include several members with diverse length and mode of action, has unraveled novel mechanisms of gene expression regulation often malfunctioning in cancer. Increasing evidence indicates that such non-coding molecules also feature in the pathobiology of PC dyscrasias, where they are endowed with strong therapeutic and/or prognostic potential. In this review, we aim to summarize the most relevant findings on the biological and clinical features of the non-coding RNA landscape of malignant PCs, with major focus on multiple myeloma. The most relevant classes of non-coding RNAs will be examined, along with the mechanisms accounting for their dysregulation and the recent strategies used for their targeting in PC dyscrasias. It is hoped these insights may lead to clinical applications of non-coding RNA molecules as biomarkers or therapeutic targets/agents in the near future.

Potential Therapeutic Roles of Exosomes in Multiple Myeloma: A Systematic Review

Multiple myeloma (MM) is the second most prevalent hematological malignancy. In spite of the remarkable progress in understanding the biology and therapy of MM, curing this disease remains difficult, which calls for more effective treatment strategies. As vital communicators between different cells, exosomes have been verified to be crucial to cancer diagnosis, treatment, and prognosis. Exosomes in MM patients show a different expression profile compared with those in healthy individuals. In this review, we summarize potential therapy roles exosomes may play in MM. The specific expression of certain components in exosomes may provide therapeutic targets. Moreover, tumor-derived exosomes and their modified products can be developed into vaccines for anti-tumor immunity. In addition, the natural nano structure of exosomes makes them excellent carriers for drug delivery. Thus, a more rigorous investigation into exosomes will pave the way for novel tumor therapies in MM patients.

Circulating microRNAs and Their Role in Multiple Myeloma

Multiple myeloma (MM) is a plasma cell dyscrasia characterized by bone marrow infiltration of clonal plasma cells. The recent literature has clearly demonstrated clonal heterogeneity in terms of both the genomic and transcriptomic signature of the tumor. Of note, novel studies have also highlighted the importance of the functional cross-talk between the tumor clone and the surrounding bone marrow milieu, as a relevant player of MM pathogenesis. These findings have certainly enhanced our understanding of the underlying mechanisms supporting MM pathogenesis and disease progression. Within the specific field of small non-coding RNA-research, recent studies have provided evidence for considering microRNAs as a crucial regulator of MM biology and, in this context, circulating microRNAs have been shown to potentially contribute to prognostic stratification of MM patients. The present review will summarize the most recent studies within the specific topic of microRNAs and circulating microRNAs in MM.

An update on extracellular vesicles in multiple myeloma: a focus on their role in cell-to-cell cross-talk and as potential liquid biopsy biomarkers

INTRODUCTION

Multiple myeloma (MM) is characterized by a clonal proliferation of neoplastic plasma cells (PCs) in bone marrow (BM) and the interplay between MM PCs and the BM microenvironment, which plays a relevant role in its pathogenesis. In this important cross-talk, extracellular vesicles (EVs) are active. EVs, including small and medium/large EVs, are lipid bi-layer particles released in circulation by normal and neoplastic cells. A selected cargo of lipids, proteins, and nucleic acids is loaded into EVs, and delivered locally and to distant sites, thus influencing the physiology of recipient cells. In the 'liquid biopsy' context, EVs can be isolated from human biofluids proving to be powerful markers in cancer. Areas covered: Here, we summarize the recent advances on EVs in MM field. Expert commentary: EVs from MM PCs: i) enhance malignant cell proliferation and aggressiveness through an autocrine loop; ii) are able to transfer drug resistance in sensitive-drug cells; iii) stimulate angiogenesis; iv) increase the activity of osteoclasts; v) have immunosuppressive effects. In addition, EVs from MM stromal cells also promote MM cell proliferation and drug resistance. Finally, we underline the importance of EVs as MM potential biomarkers in 'cancer liquid biopsy' and as a potential new therapeutic target.

The future of myeloma precision medicine: integrating the compendium of known drug resistance mechanisms with emerging tumor profiling technologies

Multiple myeloma (MM) is a hematologic malignancy that is considered mostly incurable in large part due to the inability of standard of care therapies to overcome refractory disease and inevitable drug-resistant relapse. The post-genomic era has been a productive period of discovery where modern sequencing methods have been applied to large MM patient cohorts to modernize our current perception of myeloma pathobiology and establish an appreciation for the vast heterogeneity that exists between and within MM patients. Numerous pre-clinical studies conducted in the last two decades have unveiled a compendium of mechanisms by which malignant plasma cells can escape standard therapies, many of which have potentially quantifiable biomarkers. Exhaustive pre-clinical efforts have evaluated countless putative anti-MM therapeutic agents and many of these have begun to enter clinical trial evaluation. While the palette of available anti-MM therapies is continuing to expand it is also clear that malignant plasma cells still have mechanistic avenues by which they can evade even the most promising new therapies. It is therefore becoming increasingly clear that there is an outstanding need to develop and employ precision medicine strategies in MM management that harness emerging tumor profiling technologies to identify biomarkers that predict efficacy or resistance within an individual's sub-clonally heterogeneous tumor. In this review we present an updated overview of broad classes of therapeutic resistance mechanisms and describe selected examples of putative biomarkers. We also outline several emerging tumor profiling technologies that have the potential to accurately quantify biomarkers for therapeutic sensitivity and resistance at genomic, transcriptomic and proteomic levels. Finally, we comment on the future of implementation for precision medicine strategies in MM and the clear need for a paradigm shift in clinical trial design and disease management.

Emerging roles of noncoding RNAs in multiple myeloma: A review

Multiple myeloma (MM) is a hematologic malignancy characterized by unrestricted secretion of monoclonal immunoglobulin and uncontrolled plasma cell proliferation. Extra-medullary infiltration and drug resistance are two major obstacles in the treatment of MM. To solve these problems, it is necessary to elucidate the underlying pathological mechanisms and find new therapeutic targets. Noncoding RNAs (ncRNAs), which were once considered "transcriptional noise," have been recognized as crucial regulators in the process of tumorigenesis including MM. Increasing evidence has shown that ncRNAs participate in MM pathogenesis via a series of complex cellular or extracellular processes. This review article summarizes examples of ncRNAs involved in myelosis and discusses their potential as biomarkers and therapeutic targets in the diagnosis and treatment of myelosis.

A Challenge to Aging Society by microRNA in Extracellular Vesicles: microRNA in Extracellular Vesicles as Promising Biomarkers and Novel Therapeutic Targets in Multiple Myeloma

Multiple myeloma (MM) is a malignancy of terminally differentiated plasma cells and is the second most common hematological cancer. MM frequently occurs in the elderly population with the median age as the middle sixties. Over the last 10 years, the prognosis of MM has been dramatically improved by new therapeutic drugs; however, MM is still incurable. The pathogenesis of MM is still unclear, thus greater understanding of the molecular mechanisms of MM malignancy is desirable. Recently, microRNAs (miRNAs) were shown to modulate the expression of genes critical for MM pathogenesis. In addition, miRNAs are secreted via extracellular vesicles (EVs), which are released from various cell types including MM cells, and these miRNAs are involved in multiple types of cell-cell interactions, which lead to the malignancy of MM. In this review, we summarize the current knowledge regarding the role of miRNA secretion via EVs and of EVs themselves in MM development. We also discuss the potential clinical applications of EVs as promising biomarkers and new therapeutic targets for improving the outcome of MM, resulting in a brighter future for aging societies.