塞来昔布对宫颈癌HeLa细胞凋亡及环氧合酶-2表达的影响

Effects of celecoxib on apoptosis and COX-2 expression in human cervical cancer HeLa cell line

背景与目的:环氧合酶-2(cyclooxygenase-2,COX-2)是花生四烯酸转变为前列腺素过程中的关键酶,在多种恶性肿瘤的发生、发展过程中起重要调控作用,近年来其被证实与宫颈癌的发生、发展、浸润、转移、复发和预后关系密切。塞来昔布作为一种选择性COX-2抑制剂,在肿瘤的预防和治疗中已显示其优越性和广阔前景。本研究通过观察塞来昔布对宫颈癌HeLa细胞凋亡和COX-2表达的影响,探讨塞来昔布抗肿瘤的作用机制。方法:体外培养宫颈癌HeLa细胞,以倒置相差显微镜观察不同浓度塞来昔布作用不同时间下的HeLa细胞形态学变化;DAPI荧光化学法及DNA琼脂糖凝胶电泳检测细胞凋亡情况;Western blot检测COX-2蛋白的表达。结果:HeLa细胞经塞来昔布处理后生长相对缓慢,出现典型细胞凋亡形态学改变,并随药物浓度增加及作用时间延长而显著改变。塞来昔布能诱导HeLa细胞凋亡,凋亡率随药物浓度增加而逐渐增高(F=46.810,P=0.002),DNA梯形条带明显,并呈浓度依赖性。塞来昔布呈时间及药物浓度依赖式降低COX-2蛋白的表达。结论:塞来昔布在体外通过抑制COX-2表达,诱导宫颈癌HeLa细胞凋亡。

Background and purpose：Cyclooxygenase-2（COX-2）,which is the key enzyme in the process of catalyzing arachidonic acid into prostaglandins,plays an important role in the progression of many malignant tumors and has also been confirmed to be relevant to the carcinogenesis,development,metastasis,recurrence and prognosis of cervical cancer.Celecoxib,a COX-2 selective inhibitor,has shown superiority and broad prospects in the chemoprevention and treatment of cancer.In this study,we investigated the effects of celecoxib on apoptosis and COX-2 expression in human cervical cancer HeLa cell line.Methods：HeLa cells were treated by celecoxib using various concentrations for different lengths of time.An inverted photo contrast microscope was used to observe the morphological change of HeLa cells treated with celecoxib.Cell apoptosis was examined using DAPI fluorescence cytochemistry and DNA agarose gel electrophoresis.The expression of COX-2 protein of HeLa cells was detected using the Western Blot method.Results：HeLa cells grew slowly,showing typical apoptosis morphology with increased the concentration and treatment time of celecoxib.DAPI staining indicated that celecoxib could induce apoptosis.The apoptosis rates gradually increased with increased concentrations of celecoxib（F=46.810,P=0.002）.DNA agarose gel electrophoresis showed typical DNA ladder in a dose-dependent manner when treated with celecoxib.Western blot showed that celecoxib decreased the expression of COX-2 in a time-and dose-dependent manner.Conclusion：Celecoxib may induce apoptosis of the HeLa cell line by inhibiting the expression of COX-2.