目的：探讨CDH17 在胃癌细胞中的表达及其对胃癌侵袭性的影响。方法：分别用Transwell 侵袭实验、免疫荧光染色及Western blot 法检测正常胃黏膜GES-1 细胞和胃癌MGC803 细胞与BGC823 细胞的侵袭力与CDH17、上皮标志物E-cadherin、间质标志物N-cadherin 的表达，以及两种胃癌细胞转染CDH17siRNA 后以上指标的变化。结果：正常胃黏膜GES-1 细胞无穿膜细胞、无CDH17 与N-cadherin 表达，而有明显的E-cadherin 表达；与GES-1 细胞比较，两种胃癌细胞均有明显的穿膜细胞及明显的CDH17 与N-cadherin 表达，而E-cadherin 呈低表达（均P<0.05），且高侵袭力的MGC803 细胞上述变化较低侵袭力的BGC823 细胞更为明显；两种胃癌细胞转染CDH17siRNA 后，上述指标变化较转染前明显抑制（均P<0.05），且在两种细胞间的差异缩小（均P>0.05）。结论：CDH17 高表达可能通过上皮间质转化促进胃癌细胞系侵袭性。
Influence of CDH17 on invasion ability of gastric cancer cells and the mechanism
Objective: To investigate the CDH17 expression in gastric cancer cells and its influence on the invasiveness of gastric cancer cells. Methods: The invasion ability and expressions of CDH17, epithelial marker E-cadherin and mesenchymal marker N-cadherin in normal gastric mucosal GES-1 cells, and gastric cancer MGC803 and BGC823 cells were examined by Transwell migration assay, immunofluorescence staining and Western blot analysis, respectively, and the changes in above parameters in the two types of gastric cancer cells after transfection with CDH17siRNA were also determined. Results: No invading cells or CDH17 and N-cadherin expression, but evident E-cadherin expression was seen in normal gastric mucosal GES-1 cells. In either MGC803 or BGC823 cells compared with GES-1 cells, there was considerable number of invading cells as well as marked CDH17 and N-cadherin expressions, but significantly reduced E-cadherin expression (all P<0.05), and further, the changes in these parameters in highly invasive MGC803 cells were more evident than those in less invasive BGC823 cells. After CDH17siRNA transfection, the changes in above parameters in both types of gastric cells were significantly weakened compared with those before transfection, and the differences of which between the two types of cells were decreased (all P>0.05). Conclusion: High CDH17 expression can promote invasion ability of gastric cancer cells, probably via epithelialmesenchymal transition.