蟾蜍毒素诱导结肠腺癌细胞HT-29凋亡中对相关蛋白的影响

目的 探讨蟾蜍毒素诱导结肠癌细胞株HT-29凋亡及其机制.方法 MTI检测蟾蜍毒素对结肠腺癌细胞HT-29增殖抑制；瑞氏-吉姆萨染色观察细胞形态学变化；流式细胞术分析细胞凋亡；Western-Blot检测livin、Bcl-2、Bax及Capase-3蛋白的表达.结果 蟾蜍毒素抑制HT-29细胞增殖,呈时间、剂量依赖关系；蟾蜍毒素诱导HT-29细胞凋亡,形态学观察到典型的凋亡小体；流式细胞仪检测到明显亚二倍体凋亡峰；蟾蜍毒素诱导细胞凋亡过程中下调livin、Bcl-2蛋白表达,上调Bax蛋白表达,并活化Caspase-3蛋白.结论 蟾蜍毒素诱导HT-29细胞凋亡可能与下调livin、Bcl-2蛋白、上调Bax蛋白表达并活化Caspase-3有关.

Effect of apoptosis of colorectal cancer cell line HT-29 induced by bufotoxin on its related protein

Objective To study the apoptosis of colon cancer cell line HT-29 cells induced by bufotoxin and its mechanism.Methods Inhibitory effect of bufotoxin on proliferation of colon cancer HT-29 cells was detected by MTT test.Changes in cell morphology were observed with Wright-Giemsa staining.Apoptosis of colon cancer HT-29 cells was analyzed by flow cytometry.Expressions of livin,Bcl-2,Bax and capase-3 protein were detected by Western blotting.Results Bufotoxin inhibited the proliferation of colon cancer HT-29 cells in a time–and dose-dependent manner and induced their apoptosis.Typical apoptotic bodies were observed.Flow cytometry showed a significant peak of hypodiploid apoptosis.The expressions of livin and Bcl-2 were down-regulated while the expression of Bax was up-regulated during the apoptosis of colon cancer HT-29 cells induced by bufotoxin.Bufotoxin also activated caspase-3 protein.Conclusion Bufatoxin induces apoptosis of colon cancer HT-29 cells possibly by down-regulating the expressions of livin and Bcl-2 protein,up-regulating the expression of Bax protein and activating caspase-3.