Over-regulation of microRNA-133b inhibits cell proliferation of cisplatin-induced non-small cell lung cancer cells through PI3K/Akt and JAK2/STAT3 signaling pathway by targeting EGFR.

The present study determined the anticancer activity and its mechanism of microRNA‑133b on cell proliferation of cisplatin-induced non-small cell lung cancer cells. The expression of microRNA-133b cisplatin‑induced non-small cell lung cancer (NSCLC) tissue was lower than that of para-carcinoma tissue in patients. Overall survival of higher expression in cisplatin-induced NSCLC patients was higher than that of lower expression in cisplatin‑induced NSCLC patients. Over-regulation of microRNA-133b inhibited cell proliferation and LDH activity, induced apoptosis and caspase-3 activity, suppressed the protein expression of EGFR, PI3K, p-Akt, p-JAK2 and p-STAT3, decreased cyclin D1 and increased Bax protein expression in cisplatin‑induced A549 cells. EGFR inhibitor (lapatinib) suppressed EGFR protein expression, inhibited cell proliferation and LDH activity, and induced apoptosis and caspase-3 activity in cisplatin-induced A549 cells by over-regulation of microRNA-133b. When EGFR protein expression was suppressed, PI3K, p-Akt, p-JAK2 and p-STAT3, decreased cyclin D1 and increased Bax protein expression in cisplatin-induced A549 cells by over-regulation of microRNA-133b. Altogether, our results indicated that over-regulation of microRNA-133b inhibits cell proliferation of cisplatin-induced NSCLC by PI3K/Akt and JAK2/STAT3 signaling pathway by targeting EGFR.