大肠癌细胞表达的Fas配体具有功能性

Functional expression of Fas ligand in human colon cancer cells

目的 :探讨大肠癌细胞 Fas配体 (Fas L ) m RNA和蛋白的表达及其功能。方法 :分别采用 RT- PCR和 Western印迹法以及氚释放细胞活性测定技术检测大肠癌细胞株中 Fas L m RNA和蛋白的表达及其功能。结果 :所检测的 6株大肠癌细胞(RPMI 4788、HCT- 116、DL D- 1、L o Vo、Wi Dr和 COL O 32 0 DM)全部表达 Fas L m RNA和蛋白 ;DL D- 1,L o Vo和 Wi Dr等部分大肠癌细胞具有 Fas依赖的细胞毒活性。其中 DL D- 1细胞活性具有量效关系 ,并且乙酸肉豆蔻佛波醇 (PMA )和离子霉素(ionom ycine )刺激能显著增强 DL D- 1的细胞活性。结论 :DL D- 1、L o Vo和 Wi Dr等 3株大肠癌细胞表达功能性 Fas配体 ,并可能以此反击机体免疫系统 ,逃避免疫监督。

Objective: To investigate the expression and function of Fas ligand (FasL) in human colon carcinoma cells. Methods: A total of 6 human colon cancer cell lines were examined for FasL mRNA and protein expression, Fas-dependent cytotoxicity and its modulation were detected by using RT-PCR, Western blot and 3H-TdR release assay. Results: FasL mRNA and protein was expressed in all of these 6 cancer cell lines RPMI 4788, HCT-116, DLD-1, LoVo, WiDr and COLO 320DM. Fas-dependent cytotoxicity to hFas transfectant was exerted in part of these cancer cells, such as DLD-1, LoVo and WiDr. The cytotoxicity was significantly enhanced by PMA and ionomycin. Conclusion: These data suggest that functional FasL is expressed, at least in part, in human colon cancer cell lines and may help to escape from immune surveillance of the host.