Abstract: Objective: To investigate the effect of sodium selenite, resveratrol and their combination on the proliferation and apoptosis of lung cancer cell line A549 cells and to explore the underlying mechanisms. Methods: Methyl thiazolyl tetrazolium (MTT) method was used to assess the individual and combined effects of sodium selenite and resveratrol on proliferation and survival of A549 cells. The cell apoptosis rate and cell cycle were determined by flow cytometry. Results indicated that sodium selenite and resveratrol had an antagonistic effect on A549 cells in a concentration-dependent manner, and the effect was very significant at a concentration ≥ 5 μmol/L for sodium selenite and ≥ 65 μmol/L for resveratrol (P < 0.01). The median lethal doses of (LD50) of sodium selenite and resveratrol for A549 cells were 4.759 and 45.24 μmol/L, respectively. However, when sodium selenite and resveratrol were used in combination, a synergistic effect was observed. The combination of low-dose sodium selenite and resveratrol inhibited A549 cells as effectively as high-dose sodium selenite, greatly reducing the cytotoxicity of high-dose sodium selenite. In addition, the combination of sodium selenite and resveratrol arrested the cell cycle at the G0/G1 phase and ultimately led to cell apoptosis.

Key words: sodium selenite, resveratrol, lung cancer A549 cells, cell cycle, cell apoptosis