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

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.