摘要
目的探究转录信号传导子和激活子3(Stat3)信号传导通路与选择性环氧化酶2(COX-2)抑制剂抗结肠癌细胞株HT-29机制的关系,明确COX-2抑制剂抗结肠癌细胞内信号传导机制。方法将选择性COX-2抑制剂NS-398,作用于结肠癌细胞系HT-29,运用MTT法检测细胞增殖状态;流式细胞仪观察NS-398对细胞凋亡的影响,进一步用RT-PCR检测药物作用前后HT-29中COX-2mRNA的表达;ELISA法测定体系前列腺素E2(PGE2)水平;Westernblot检测药物作用前后Stat3通路相关蛋白JAK2、Stat3的磷酸化活性和cyclinD1、Bcl-2的表达。结果结肠癌细胞系HT-29中COX-2mRNA呈高表达,NS-398呈时间、剂量依赖性方式抑制HT-29细胞增殖,促进其凋亡。NS-398使HT-29细胞COX-2mRNA和PGE2表达水平显著下降。同时p-JAK2、p-Stat3、cyclinD1、Bcl-2表达水平随作用时间延长而下降。结论癌基因Stat3信号传导通路调控了NS-398抗结肠癌的细胞内信号传导机制,最终通过其下游靶基因cyclinD1、Bcl-2影响结肠癌细胞系HT-29的增殖与凋亡。
Objective To investigate the relationship between the role of signal transducers and activators of transcription factor 3(Stat 3) signal transduction pathway and the mechanism of selective cyclooxygenase 2(COX 2) inhibitor,NS 398 against human colon cancer cell line HT 29. Methods HT 29 cells were treated with NS 398. MTT assay and flow cytometry were used to measure the cell proliferation and apoptosis. RT PCR and ELISA were used to detect the COX 2 mRNA expression level and PGE2 concentration of HT 29 cells,before and after treatment respectively. The expression of p Stat 3,p JAK2,cyclin D1 and Bcl 2 proteins was examined by Western blot. Results The high expression of COX 2 mRNA was detected in HT 29 cells. After treated by NS 398,an obvious decline in expression of COX 2 mRNA and PGE2 were found,along with the cells proliferation inhibiton and apoptosis induction in a dosage ,time dependent manner. A significant downregulation of p Stat 3,p JAK2,cyclin D1 and Bcl 2 expression was found with the treatment time. Conclusions Stat 3 signaling pathway may mediate the proliferative inhibition and apoptotic induction of HT 29 cells through the downregulation of cyclin D1,Bcl 2 expression.
出处
《中华胃肠外科杂志》
CAS
2004年第5期404-406,共3页
Chinese Journal of Gastrointestinal Surgery
基金
国家自然科学基金(30271269)
2002年教育部科学技术研究重点项目(02003)
