塞来昔布对大肠癌细胞株HT-29增殖和凋亡的影响

目的体外观察塞来昔布对大肠癌细胞株HT-29细胞增殖和凋亡的影响,探讨其可能的作用机制.方法采用噻唑蓝(MTT)比色法,流式细胞(FCM)、吖啶橙/溴化乙啶染色结合荧光显微镜、Western印迹法等技术,研究塞来昔布对HT-29细胞增殖的抑制和可能的机制.结果塞来昔布抑制HT-29细胞生长,呈浓度和时间依赖性.流式术检测出典型的亚二倍体"凋亡峰",凋亡率(7.31±2.37)%～(48.30±2.86)%;使G0/G1期细胞比例升高,S期和G2/M期比例缩小、细胞核固缩、凋亡小体形成等.凋亡比例呈剂量和时间依赖.塞来昔布降低细胞周期素依赖蛋白激酶CDK2和CDK4的表达、上调细胞周期素依赖蛋白激酶抑制因子p21WAF1/CIP1n蛋白表达.结论体外塞来昔布抑制HT-29细胞增殖,并诱导细胞凋亡;下调CDK2和CDK4蛋白表达,上调P21WAF1/CIPln蛋白表达.塞来昔布抑制HT-29细胞增殖、诱导凋亡可能与阻止细胞周期进展有关.

Effects of Celecoxib on cell proliferation and apoptosis in human colorectal cancer cell line HT-29

Objective: To study the effect of Celecoxib on cell proliferation and apoptosis of human colorectal cancer cell line HT-29 and the probable mechanism involved. Methods: Using MTT assay, flow cytometry (FCM),Acridine orange and Ethidium bromide staining under lluorescence microscope, Western blotting, the effect of Celecoxib on the HT-29 of proliferation and related mechanism were studied. Results: The growth of HT-29 was inhibited by Celecoxib in a dose-and time- dependent manner. Sub-G1 peak was detected by FCM, and the apoptotic rate was between (7.31±2.37)% and (48.30±2.86)%. The cell ratios of G0/G1 increased, whereas the cell ratios of S and G2/M phase decreased after treatment and was in a dose-dependent manner. The HT-29 cell line exhibited some morphologie feature of apoptosis, including cell shrinkage, nuclear condensation, DNA fragmentation, and formation of apoptosis bodies, and apoptotic index was in a dose-and time-dependent manner under Acridine orange and Ethidium bromide staining. Celecoxib down-regulated the expressions of CDK2, CDK4 proteins and up-regulated the expression of p21WAF1/CIP1 protein. Conclusions: Celecoxib inhibits proliferation and inducs apoptosis of human colorectal cancer cell line HT-29, down-regulats the expressions of CDK2, CDK4 proteins and up-regulats the expression of P21WAF1/CIP1 protein. The effect of Celecoxib on phase of cell cycle may be partially explained as the cytotoxic effects of Celecoxib.