Effect of apigenin on apoptosis and expression of Bax and Bcl-2 in A549 human lung cancer cells

Objective To investigate the effect of apigenin on proliferation, and apoptosis, as well as Bax and Bcl-2 protein expression in human lung cancer cell line A549. Methods A549 cells cultured in vitro were treated with 10 ~ 80 μmol/L different concentration of apigenin. MTT was used to detect the inhibitory rates according to the formula. Apoptosis of A549 cells was observed in a fluorescence microscope by Hoechst 33258 staining and quantified by flow cytometry using annexin V-FITC/PI staining. The expressions of apoptosis-related protein Bax and Bcl-2 were analyzed by Western blot. Results The inhibition of proliferation by apigenin was concentration-dependent and time-dependent. A549 cells treated with apigenin showed significant morphological changes in different apoptotic phases. The apoptotic rate was concentration-dependently increased. Western blot analysis indicated that apigenin increased the protein level of Bax, and reduced the protein level of Bcl-2. Conclusion Apigenin can inhibit proliferation and induce apoptosis of human lung cancer cell line A549, which might be related with up-regulated expression of Bax and down-regulated expression of Bcl-2.