羽扇豆醇影响肝癌细胞株SMMC-7721增殖与凋亡的机制

Effect of lupeol on proliferation and apoptosis of hepatic carcinoma SMMC-7721 cells

目的:讨论羽扇豆醇影响肝癌细胞株SMMC-7721增殖及促进其凋亡作用机制.方法:使用不同浓度(0、2、5、10、20μg/m L)的羽扇豆醇在不同处理时间(24、36、48 h)下,处理S M M C-7721细胞株后,通过MTT法检测SMMC-7721细胞增殖情况;对使用不同浓度的羽扇豆醇处理48 h后的SMMC-7721细胞,利用流式细胞仪检测S M M C-7721细胞的细胞周期以及细胞凋亡情况,还使用Western blot检测细胞细胞增殖细胞核抗原(proliferating cell nuclear a n t i g e n,P C N A)、B淋巴细胞瘤-2(B-c e l l lymphoma-2,Bcl-2)基因及Bcl-2相关X蛋白(Bcl-2 associated X protein,Bax)蛋白的表达情况,最后我们通过免疫组织化学的方式检测在裸鼠体内接种的SMMC-7721细胞瘤体的微血管密度(microvessel density,M V D)值,检测羽扇豆醇对抑制肿瘤血管生成的作用.结果:相较于对照组,通过不同浓度的羽扇豆醇处理后的SMMC-7721细胞增殖水平均受到不同程度的抑制,而且既显示出量效关系又显示出时效关系;受到羽扇豆醇体外诱导处理后的SMMC-7721细胞能够使G0/G1期受到阻滞,甚至出现凋亡现象,SMMC-7721细胞的PCNA和Bcl-2蛋白表达情况下调,Bax蛋白的表达情况上调(P<0.05).肿瘤瘤体MVD值下降(P<0.01).结论:SMMC-7721细胞的增殖会因为羽扇豆醇的处理而受到抑制,并且还会因为羽扇豆醇的处理而出现凋亡.羽扇豆醇还可以抑制肿瘤瘤体血管生成.

AIM： To investigate the effect of lupeol on the growth and apoptosis of hepatic carcinoma SMMC-7721 cells and explore the mechanism involved. METHODS： After SMMC-7721 cells were treated by different concentrations of lupeol（0, 2, 5, 10, 20 μg/m L） for different durations（24,36 or 48 h）, cell proliferation was determined by MTT assay. The SMMC-7721 cells were also tested by flow cytometry after treatment with different concentrations of lupeol for 48 h. The expression of proliferating cell nuclear antigen（PCNA）, B-cell lymphoma-2（Bcl-2） and Bcl-2 associated X protein（Bax） in SMMC-7721 cells was tested by Western blot. Xenograft tumors of SMMC-7721 grown in nude mice were tested by immunohistochemistry to assess the microvessel density（MVD） and the effect of lupeol on angiogenesis.RESULTS ： Compared with the control group, the proliferation of SMMC-7721 cells was inhibited by lupeol in a time and concentration dependent manner. The cell cycle of SMMC-7721 cells was blocked at G0/G1 by lupeol. Lupeol also resulted in apoptosis. Lupeol up-regulated the expression of PCNA and Bcl-2, down-regulated the expression of Bax（P〈 0.05）, and decreased MVD（P 〈0.01）. CONCLUSION： Lupeol can inhibit SMMC-7721 cell proliferation and induce cell apoptosis.