Inhibition of berberine on growth of human nasopharyngeal carcinoma cells CNE-2 in vivo and in vitro

Objective To study the inhibitory effect of berberine on human nasopharyngeal cancer cell line CNE-2 in vivo and in vitro. Methods CNE-2 cell proliferation was measured by MTT assay and cell cycle was analyzed by flow cytometry. Cell morphology was observed with transmission electron microscopy. The cell cycle relative protein was detected by Western blotting. DNA and protein syntheses were assessed by the cellular incorporation of ~ 3 H-TdR and ~ 3 H-Leu, respectively. Anti-tumor activity of berberine in the experimental transplantation tumor CNE-2 was evaluated by relative tumor growth ratio. Results Berberine inhibited CEN-2 cells growth in a time-and dose-dependent manner. MTT Assay showed that the IC_ 50 values of 48 and 72 h were (49.5±5.8) and (13.3±2.0) μmol/L, respectively. Cell cycle analyses of 50.0 μmol/L berberine-treated CNE-2 cells by flow cytometry showed the accumulation of cells in the G_2/M phase while 25.0 μmol/L berberine treatments for 48 h induced apoptosis with the index of (48.9±10.4)%. The inhibition of CNE-2 cell growth by berberine was associated with suppression of cyclin B1, CDK1, and cdc25c proteins. After the treatment of berberine at dose of 30 mg/kg, the median tumor volume was 317.9 mm~3 which was much lower than that in control group (P0.05) in nude mice bearing human nasopharyngeal cancer. Conclusion Berberine has inhibitory effect on the growth of CNE-2, which might be related to its inhibition of cyclin B, cdc25c, and CDK1 proteins.