miR-423-5p enhances chemoresistance of glioblastomas cells to temozolomide by regulating PDCD5 / 中国肿瘤生物治疗杂志

ABSTRACT

@#[Abstract] Objective: To investigate the miR-423-5p expression in brain glioma tissues and cell lines, and its promotive effect on temozolomide (TMZ) chemoresistance by targeting PDCD5 (programmed cell death protein 5). Methods: Tumor tissues and matched peritumoral tissues were collected from 20 brain glioma patients who were surgically treated in the Department of Neurosurgery, Affiliated Hospital of Beihua University between January 2017 and December 2018. Glioblastoma cell lines (U251, U87, SHG-44) and human normal glial cell line HMC-3 were also used in the study. The relative expression of miR-423-5p and PDCD5 in brain glioma and peritumoral tissues and cell lines was detected by qPCR. The synthesized miR-423-5p mimics and miR-NC were respectively transfected into U251 and U87 cells; meanwhile, TMZ at different concentrations (50, 100, 150 and 200 μmol/L) were also used to treat the cells. Then, the chemoresistance of cells to TMZ were determined. MTT assay and colony formation assay were used to examine the proliferation of U251 and U87 cells, andWestern blotting was used to detect the expression of c-caspase 3, Bcl-2 and PDCD5 proteins in U251 and U87 cells. The targeting relationship between PDCD5 and miR-423-5p was validated through Dual luciferase reporter gene assay. Results: miR-423-5p was highly expressed in glioma tissues and glioma cell lines (all P<0.01). As compared with the miR-NC group, the proliferation and TMZ-chemoresistance of U251 and U87 cells in miR-423-5p mimics group significantly increased (all P<0.01). Dual luciferase reporter gene assay validated that miR-423-5p could bind with PDCD5 3' UTR to suppress the expression of PDCD5. Conclusion: High expression of miR-423-5p enhances the chemoresistance of glioma cells to TMZ, and miR-423-5p may serve as a potential therapeutic target in the treatment of brain glioma.