MicroRNA-1252-5p Associated with Extracellular Vesicles Enhances Bortezomib Sensitivity in Multiple Myeloma Cells by Targeting Heparanase

Dorival Mendes Rodrigues-Junior,1,2 Maria Fernanda de Andrade Pelarin,1 Helena Bonciani Nader,1 André Luiz Vettore,3 Maria Aparecida Silva Pinhal1,4 1Department of Biochemistry, Universidade Federal de São Paulo (UNIFESP), São Paulo, Brazil; 2Institute of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden; 3Department of Biological Science, Universidade Federal de São Paulo (UNIFESP), Diadema, Brazil; 4Department of Biochemistry, Faculdade de Medicina do ABC, Santo André, BrazilCorrespondence: Dorival Mendes Rodrigues-JuniorLaboratório de Biologia Molecular do Câncer, UNIFESP, Rua Pedro de Toledo, 669 – 11° Andar, São Paulo, SP 04039-032, BrazilEmail dorivalmrjr@gmail.comMaria Aparecida Silva PinhalDepartment of Biochemistry, Universidade Federal de São Paulo (UNIFESP), Rua Três de Maio, 100, Vila Clementino, São Paulo, SP 04044-020, BrazilEmail maspinhal@yahoo.com.brIntroduction: Multiple myeloma (MM) remains an incurable disease, and patient survival requires a better understanding of this malignancy’s molecular aspects. Heparanase (HPSE) is highly expressed in aggressive MM cells and related to tumor growth, metastasis, and bortezomib (BTZ) resistance. Thus, targeting HPSE seems to be a promising approach for MM treatment, and because microRNAs (miRNAs) have emerged as potential regulators of HPSE expression, the use of extracellular vesicles (EVs) can allow the efficient delivery of therapeutic miRNAs.Methods: We used prediction algorithms to identify potential miRNAs that regulate negatively HPSE expression. RT-qPCR was performed to assess miRNAs and HPSE expression in MM lines (U266 and RPMI-8226). Synthetic miRNA mimics were electroporated in MM cells to understand the miRNA contribution in HPSE expression, glycosaminoglycans (GAGs) profile, cell proliferation, and cell death induced by BTZ. EVs derived from HEK293T cells were engineered with miRNAs to evaluate their therapeutic potential combined with BTZ.Results: It revealed a direct association between BTZ sensitivity, HPSE, and miR-1252-5p expressions. Moreover, overexpression of miR-1252-5p significantly reduced HPSE expression and HPSE enzymatic activity in MM cells. The higher level of miR-1252-5p was correlated with a reduction of cell viability and higher sensitivity to BTZ. Further, EVs carrying miR-1252-5p increased MM cells’ sensitivity to BTZ treatment.Conclusion: These results showed that miR-1252-5p could negatively regulate HPSE in MM, indicating the use of EVs carrying miR-1252-5p as a potential novel BTZ sensitization approach in MM cells.Keywords: bortezomib, cancer, extracellular vesicles, exosomes, heparanase, multiple myeloma, microRNA