miRNA-seq identification and clinical validation of CD138+ and circulating miR-25 in treatment response of multiple myeloma

Small RNA-seq and clinical evaluation of tRNA-derived fragments in multiple myeloma: Loss of mitochondrial i-tRFHisGTG results in patients' poor treatment outcome

Despite the substantial progress in multiple myeloma (MM) therapy nowadays, treatment resistance and disease relapse remain major clinical hindrances. Herein, we have investigated tRNA-derived fragment (tRF) profiles in MM and precursor stages (smoldering MM/sMM; monoclonal gammopathy of undetermined significance/MGUS), aiming to unveil potential MM-related tRFs in ameliorating MM prognosis and risk stratification. Small RNA-seq was performed to profile tRFs in bone marrow CD138+ plasma cells, revealing the significant deregulation of the mitochondrial internal tRFHisGTG (mt-i-tRFHisGTG) in MM versus sMM/MGUS. The screening cohort of the study consisted of 147 MM patients, and mt-i-tRFHisGTG levels were quantified by RT-qPCR. Disease progression was assessed as clinical end-point for survival analysis, while internal validation was performed by bootstrap and decision curve analyses. Screening cohort analysis highlighted the potent association of reduced mt-i-tRFHisGTG levels with patients' bone disease (p = 0.010), osteolysis (p = 0.023) and with significantly higher risk for short-term disease progression following first-line chemotherapy, independently of patients' clinical data (HR = 1.954; p = 0.036). Additionally, mt-i-tRFHisGTG-fitted multivariate models led to superior risk stratification of MM patients' treatment outcome and prognosis compared to disease-established markers. Notably, our study highlighted mt-i-tRFHisGTG loss as a powerful independent indicator of post-treatment progression of MM patients, leading to superior risk stratification of patients' treatment outcome.

Role of Non-Coding RNAs in Diagnosis, Prediction and Prognosis of Multiple Myeloma

Multiple myeloma (MM) is the second most common hematologic malignancy in the world and accounts for 15% of primary hemocytopathies, with an ever-increasing number of new cases. It is asymptomatic in 30% of instances; hence, the determination of highly sensitive and specific markers is necessary to make a proper diagnosis. In the last 20 years, miRNAs, involved in regulating the expression of genes responsible for cell proliferation and differentiation, including tumor cells, have been identified as potential diagnostic and prognostic markers. The main aim of the following review was to outline the role of miRNAs in the diagnosis and prognosis of MM, considering their role in the pathogenesis of the disease and identifying their target genes and pathways. For this purpose, publications dating from 2013-2023 have been reviewed. Based on the available data, it is concluded that non-coding RNAs including miRNAs could be potential markers in MM. Furthermore, they may serve as therapeutic targets for certain drugs.