胃癌细胞上调FasL表达对胃癌细胞凋亡的影响

Effect of Up-expression of Fas Ligand on the Apoptosis of Gastric Carcinoma

目的 :观察胃癌FasL蛋白表达及其对胃癌细胞凋亡的影响。方法 :采用免疫组化染色对 5 0例手术切除的胃腺癌组织中FasL蛋白进行观察 ;采用脱氧核糖核酸末端转移酶介导的缺口末端标记 (TUNEL)技术 ,对其中 4 0例胃癌组织中胃癌细胞的凋亡情况进行原位观察。结果 :5 0例胃腺癌组织均表达FasL蛋白 ,阳性率为 10 0 % ,明显高于正常胃粘膜的 4 5 % (P <0 .0 1) ,胃腺癌组织 78%中、强表达 ,正常胃粘膜均为弱表达。随着胃癌细胞FasL表达水平的增加 ,胃癌细胞的凋亡指数逐渐下降 ,各组间差异有显著性 (P <0 .0 1) ,胃癌细胞的凋亡水平与其FasL表达呈负相关。结论 :胃腺癌细胞可能通过上调表达FasL ,间接地使胃癌细胞的凋亡下调而保护了自己 ,这可能是胃癌免疫逃逸的机制之一。

Objective:To investigate the effect of up-regulation of FasL ligand protein on the apoptosis of gastric carcinoma(GC). Methods: expression of FasL protein in 50 resected GC and apoptosis of cancer cells were detected with immunohistochemistry and terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL). Results: The expressions of FasL were detected in all of 50 resected GC with positive rate of 100%, which was significantly higher than that (45%) in control normal gastric epithelia( P <0.01).In contrast, the FasL expression was mediated or extensive in 78% of GC,( P <0.01).As the FasL expression became more extensive, the apoptosis index of GC cells decreased stepwisedly. Conclusion:Human GC may down regulate its apoptosis through up regulating its expression of FasL.Therefore,the cancer may protect itself from immune surveillence.