The role of miR-375 in the pathogenesis of gastrointestinal stromal tumors

Abstract

Introduction: Deregulated miRNA profiles and their contribution to carcinogenesis have been observed in virtually all types of cancer. However, their contribution to the pathogenesis of rare gastrointestinal stromal tumors (GISTs) is not well defined yet. In this study, we aimed to investigate the role of miR-375 - a well-known tumor-suppressive miRNA - in the pathogenesis of GIST. Materials and Methods: MirVana miRNA mimic and negative control were transfected to the GIST-T1 cell line using the lipofection technique. Target gene and protein expression were detected by RT-qPCR and Western Blot, respectively. Alterations in cell viability, migration rate and apoptotic cell counts, as well as miRNA-target gene interaction, were evaluated by MTT, Wound Healing, Annexin V FITC and Dual-Light Luciferase assays, respectively. Statistical analysis was performed using the computing environment R. Results: Overexpression of miR-375 reduced levels of KIT gene mRNA (1.9-fold, p < 0.05) and protein (1.4-fold, p < 0.05) in GIST-T1 cell line. Further functional analysis revealed a significant effect of miR-375 on cell viability (reduced by 47%, p < 0.05) and migration rates (reduced by up to 28% in different time points, p < 0.05). GIST-T1 cells with KIT 3’UTR construct (pos855-861) showed decreased luciferase activity down to 76% when miR-375 was overexpressed.