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，并探讨其可能的作用机制。方法 采用噻唑蓝（MTT）比色法，流式细胞仪（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细胞增殖抑制的影响。结果：体外塞来昔布抑制HT-29细胞生长，呈浓度和时间依赖性。DNA直方图示典型的亚二倍体“凋亡峰”，凋亡率在（7.31±2.37）%～（48.30±2.86）%；塞来昔布使G0/G1期细胞比例升高，S期和G2/M期比例下降，呈一定剂量效应关系。典型的凋亡形态学改变：细胞体积缩小、细胞核固缩、凋亡小体形成等。凋亡比例呈剂量和时间依赖。塞来昔布下调细胞周期素依赖蛋白激酶CDK2，CDK4蛋白表达、上调细胞周期素依赖蛋白激酶抑制因子P21WAF1/CIP1蛋白表达。结论：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 the proliferation and apoptosisof human colorectal cancer cell line HT-29

OBJECTIVE: To determine the effect of Celecoxib on the proliferation and apoptosis of human colorectal cancer cell line HT-29 and the probable mechanism involved. METHODS: Using MTT assay, flow cytometry, Acridine orange and Ethidium bromide staining, and Western blotting analysis, the effects of celecoxib on the proliferation and apoptosis of HT-29 cells as well as its related mechanism were studied. RESULTS: The growth of HT-29 cell was inhibited by celecoxib in a dose- and time-dependent manner. Sub-G1 peak was detected by FCM, and apoptotic rate was between (7.31 +/- 2.37) % and (48.30 +/- 2.86) %. The cell ratio of G0/G1 phase increased,whereas the cell ratio of S and G2/M phases decreased in a dose-dependent manner after the treatment. The HT-29 cell line exhibited some morphologic features of apoptosis, including cell shrinkage, nuclear condensation, DNA fragmentation, and formation of apoptosis bodies, and the apoptotic rate was in a dose- and time-dependent manner. Celecoxib down-regulated the expression of CDK2, CDK4 and up-regulated the expression of P2 WAF1/CIP1 CONCLUSION: The effect of celecoxib inhibiting cell HT-29 proliferation and inducing cell apoptosis may relate to its blocking cell cycle progress.