目的观察小檗碱体内外对人鼻咽癌CNE-2细胞生长的影响,探讨小檗碱的抗肿瘤作用机制。方法MTT法测定小檗碱对CNE-2细胞生长的抑制作用;流式细胞仪检测小檗碱对CNE-2细胞凋亡和周期的影响;透射电镜观察CNE-2细胞经小檗碱处理后凋亡形态变化;Westernblotting法检测小檗碱对CNE-2细胞的细胞周期相关蛋白(cyclin)B1、CDK1、cdc25c表达的影响;3H-胸腺嘧啶(3H-TdR)和3H-亮氨酸(3H-Leu)标记前体掺入法检测小檗碱对CNE-2细胞DNA和蛋白质合成的影响;利用荷人鼻咽癌的裸鼠模型验证小檗碱的体内抗肿瘤作用。结果小檗碱能抑制CNE-2细胞生长,48h的半数抑制浓度(IC50)为(49.5±5.8)μmol/L,72h的IC50为(13.3±2.0)μmol/L;小檗碱能抑制CNE-2细胞DNA和蛋白质合成;小檗碱能诱导CNE-2细胞凋亡,细胞经过25.0μmol/L小檗碱处理48h后的凋亡指数为(48.9±10.4)%;50.0μmol/L小檗碱能诱导CNE-2细胞G2/M期阻滞,并且下调细胞周期相关蛋白B1、CDK1、cdc25c表达;小檗碱能抑制人鼻咽癌CNE-2细胞在裸鼠体内的生长,30mg/kg剂量组的肿瘤体积中位数为317.9mm3,明显低于对照组(P<0.05)。结论小檗碱体内外均能抑制人鼻咽癌CNE-2细胞的生长,其抗肿瘤作用可能与其诱导细胞周期阻滞和凋亡,下调相关细胞周期蛋白有关。

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.