Abstract

Objective. Acute myeloid leukemia (AML) is a heterogeneous clonal disorder resulting from a complex interplay between leukemic cells and supporting factors from their mi-croenvironment. In this context, extracellular vesicles (EVs) have been shown to play an essential role in forming a tumor-protective microenvironment. In this study, we ex-amined the influence of AML-derived EVs on cellular and molecular characterization of bone marrow mesenchymal stromal cells (BM-MSCs), particularly alteration in the expression of genes (IL-6, Gas-6, and Galectin-3) relating to relapse and chemoresis-tance.Methods. MSCs were co-cultured with different concentrations of AML-EVs. Our data has been achieved by MTT assay, ROS assay, proliferation assay and apoptosis assay. RT-qPCR was also performed for gene expression analysis.Results. Our results demonstrated that AML-EVs impact the MSCs characterization in a concentration-dependent manner. We revealed higher viability, increased Ki-67 and BCL-2, and lower ROS levels in MSCs treated with a 40 mu g/mL dose of EVs. On the other hand, the rate of MSCs apoptosis and BAX expression exposed to a 60 mu g/mL dose of EVs were increased compared with the control group. In addition, RT-qPCR results showed that the expression of IL-6, Gas-6, and Galectin-3 was significantly up-regulated in treated MSCs with a 40 mu g/mL dose of EVs.Conclusion. Because the overexpression of IL-6, Gas-6, and Galectin-3 has contributed to chemoresistance and relapse, our findings suggest that AML-EVs propel MSCs to express these genes, which in turn could guard leukemic cells from chemotherapy-inflicted damages and eventually lead to relapse. (c) 2023 Published by Elsevier Inc. on behalf of Instituto Mexicano del Seguro Social (IMSS).