MicroRNAs (
miRNAs) are small non-coding regulatory RNAs, which are involved in the post-transcriptional regulation of gene expression.
miRNA (miR)-155, which has previously been reported to be overexpressed in
lung cancer, is correlated with poor patient prognosis. The present study aimed to investigate the effects of miR‑155 on the radiosensitivity of human non‑small cell
lung cancer (NSCLC) cells. To explore the roles of
miRNAs in the regulation of irradiation sensitivity of human
lung cancer cells, the expressions of miR‑155 in response to irradiation, have been studied by RT‑qPCR, and the putative direct target of miR‑155 was identified by western blot and
luciferase assays. The results of the present study revealed that the expression of miR‑155 was induced by irradiation, thus suggesting a positive correlation between miR‑155 and radiosensitivity. Furthermore, overexpression of miR‑155 rendered
lung cancer cells resistant to irradiation. In addition, hexokinase 2 (HK2) was identified as an indirect target of miR‑155; exogenous overexpression of miR‑155 upregulated the expression of HK2, whereas inhibition of miR‑155 by antisense
miRNA suppressed HK2 expression. In addition, HK2‑modulated
glucose metabolism was significantly upregulated by overexpression of miR‑155. Notably, inhibition of miR‑155 sensitized
lung cancer cells to irradiation via suppression of
glucose metabolism. In conclusion, the present study reported a novel function for miR‑155 in the regulation of NSCLC cell radiosensitivity, thus suggesting that miR‑155 may be considered a therapeutic target for the development of anticancer drugs.