Waltonitone induces apoptosis through mir-663-induced Bcl-2 downregulation in non-small cell lung cancer.

Our previous study reported that waltonitone treatment inhibited proliferation and induced apoptosis of lung cancer cells. However, the mechanism of waltonitone-induced toxicity remains unclear. In the present study, we treated H460 and H3255 lung cancer cells using different concentration of waltonitone (0, 10, 20, 30 μmol/L). We observed that waltonitone inhibited cell viability and induced apoptosis in a concentration dependent manner, with upregulation of caspase-3 cleavage. We also observed upregulation of miR-663, a potential tumor suppressor, after waltonitone treatment. Suppression of miR-663 function using miR-663 inhibitor partly alleviated cell toxicity induced by waltonitone. In addition, both waltonitone treatment and transfection of miR-663 mimic upregulated Bcl-2 mRNA and protein expression. Bcl-2 transfection alleviated waltonitone-induced toxicity. Furthermore, transfection of miR-663 inhibitor upregulated Bcl-2 levels in both cell lines. In summary, the present study demonstrated that waltonitone induced apoptosis of lung cancer cells through, at least partly, miR-663-induced Bcl-2 downregulation.