OBJECTIVE: To investigate the effects of brazilin on the proliferation, apoptosis and autophagy of human tongue squamous cell carcinoma Tca8113 cells in vitro and explore its molecular mechanism. METHODS: The changes in the proliferation, morphology and apoptosis of Tca8113 cells in response to brazilin treatment were detected using MTT assay, Hoechst33342 staining, and Annexin V/PI double staining, respectively. The expressions of apoptosis-related protein Bax, Bcl-2, cleaved caspase-3 and autophagy-related proteins p-AMPK, p-mTOR, LC3B, and p62 in the treated cells were detected using Western blotting. The effect of treatment with both the AMPK pathway inhibitor and brazilin on the expressions of the pathway-related proteins p-AMPK, p-mTOR, and LC3B was assessed. RESULTS: MTT assay showed that brazilin significantly inhibited the proliferation of Tca8113 cells with an IC50 of 31.17 μmol/L at 24 h. Hoechst33342 staining showed that brazilin induced apoptotic morphological changes in Tca8113 cells in a concentration-dependent manner. Treatment with different concentrations of brazilin resulted in increased apoptosis in the cells. Brazilin obviously inhibited the expression of Bcl-2, p62 and p-mTOR and enhanced the expressions of Bax, cleaved caspase-3, LC3B and p-AMPK. The AMPK pathway inhibitor significantly inhibited the increase in p-AMPK and LC3B expressions and the decrease in p-mTOR expression induced by brazilin. CONCLUSIONS Brazilin can inhibit the proliferation and promote apoptosis in Tca8113 cells and at the same time induces autophagy in the cells through the AMPK/mTOR pathway.
Apoptosis ; Autophagy ; Benzopyrans ; Cell Line, Tumor ; Cell Proliferation ; Humans ; Tongue Neoplasms