Upregulation of microrna-451 increases the sensitivity of A549 cells to radiotherapy through enhancement of apoptosis

Abstract

Background: As radioresistance of non-small cell lung cancers (NSCLC) is one of the main causes of failure in radiotherapy, we examined whether micro ribonucleic acid (miR-451) could function as a potential radiosensitizer of NSCLC and the related mechanism. Methods: Radioresistant NSCLC cell line A549 was transfected with pre-miR-451 or a scrambled control. The miR-451 messenger RNA level, colony-forming ability, apoptosis, and phosphatase and tensin homolog (PTEN) protein level of 549 cells were examined by real-time polymerase chain reaction, clonogenic assay, flow cytometry analysis, and Western blot. Results:Upregulation of miR-451 enhanced the suppressive effects of irradiation on the colony-forming ability of A549 cells. The apoptosis and PTEN expression of A549 cells post-irradiation were also enhanced by upregulation of miR-451. Conclusions: Upregulation of miR-451 sensitized radioresistant NSCLC A549 cells to irradiation through the enhancement of apoptosis. The activation of PTEN post-irradiation was possibly correlated with the radiosensitization of A549 cells induced by miR-451 overexpression.