Abstract
Among patients with primary lung cancer, 75-80% present with non-small cell lung cancer (NSCLC). However, there is a lack of studies into the potential preventive effects of curcumin against the activation of autophagy in NSCLC. Therefore, the present study primarily focused on the protective role of curcumin in NSCLC. It was demonstrated that curcumin decreased the viability of the human lung cancer cells lines, A549 and H1299, in a time-and dose-dependent manner (P<0.05). Treatment with curcumin also suppressed the colony formation capacities of A549 and H1299 cells. Following incubation with 10 µM curcumin for 48 h, cell apoptosis was significantly increased by 2.35- and 3.02-fold in A549 and H1299 cells, respectively, when compared with controls (P<0.01). Furthermore, curcumin treatment markedly increased the number and volume of autophagosomes in A549 and H1299 cells when compared with controls. Treatment with 10 µM curcumin for 48 h also significantly reduced the phosphorylation levels of mechanistic target of rapamycin (mTOR), ribosomal protein S6, phosphoinositide 3-kinase and AKT (protein kinase B) in A549 and H1299 cells (P<0.05). These data indicated that curcumin enhanced autophagy and apoptosis in NSCLC cells by acting as an mTOR complex1/2 inhibitor.