miR-378a-3p regulates glioma cell chemosensitivity to cisplatin through IGF1R

Glioma is a type of common intracranial tumor. In this study, we investigated the molecular mechanism by which miR-378a-3p regulates cisplatin (CDDP) chemosensitivity in glioma cells via insulin-like growth factor 1 receptor (IGF1R). U251/CDDP cells were treated with CDDP and transfected with miR-378a-3p mimics, NC mimics, or pcDNA-IGF1R. qRT-PCR was used to measure the differential level of miR-378a-3p. CCK-8 assay was used to test cell proliferation, and flow cytometry was used to analyze apoptosis. The targeting relationship between miR-378a-3p and IGF1R was tested through a dual-luciferase reporter gene assay. In contrast to normal glial cells, the miR-378a-3p level decreased in human glioma U251 cells and had lower expression in U251/CDDP cells. Compared with the CDDP group, miR-378a-3p significantly caused the inhibition of U251/CDDP cell proliferation and enhanced apoptosis in the miR-378a-3p mimics + CDDP group. Another experiment confirmed that IGF1R was a target gene of miR-378a-3p, and overexpression of miR-378a-3p inhibited IGF1R expression. In addition, co-overexpression of miR-378a-3p and IGF1R induced the upregulation of the U251/CDDP cell proliferation and the inhibition of apoptosis in the miR-378a-3p mimics + pcDNA-IGF1R + CDDP group. This study confirmed that miR-378a-3p promoted the sensitivity of glioma cells to CDDP in glioma patients via targeting IGF1R to increase the therapeutic effect during chemotherapy.