胰岛素样生长因子-Ⅰ受体与胃癌发生发展关系的研究

目的 研究胰岛素样生长因子-Ⅰ受体(IGF-IR)与胃癌发生发展的关系.方法 应用免疫组化法检测40例手术切除胃癌组织及其远端正常胃黏膜中IGF-IR表达水平.Western印迹法检测胃癌细胞系SGC7901和MGC803中IGF-IR的表达水平.设计并体外合成靶向IGF-ⅠR的小干扰RNA,将其转染到MGC803细胞中,Western印迹法检测转染后48 h IGF-ⅠR蛋白表达水平,MTT法检测细胞增殖能力,细胞计数并描记生长曲线.结果 胃癌组织IGF-IR表达阳性率为75.5%,显著高于远端正常胃黏膜(25%,P＜0.01).IGF-IR表达与TNM分期和淋巴结转移相关(P＜0.05),但与性别、年龄、分化程度、肿瘤浸润深度无关(P＞0.05).胃癌细胞株中有IGF-ⅠR高表达,小干扰RNA1组IGF-ⅠR表达抑制率可高达89.80%±4.10%,转染后第5天细胞增殖降至最低点(为空细胞组的29.0%±4.0%),同期细胞数降至对照组的21.15%±1.10%.结论 IGF-ⅠR在胃癌细胞中过表达,应用RNA干扰技术可有效沉默IGF-IR基因,抑制肿瘤细胞的增殖.

A preliminary study on the relationship of insulin-like growth factor-Ⅰ receptor and the carcinogenesis of gastde cancer

Objective To study the relationship of insulin-like growth factor-Ⅰ receptor(IGF-ⅠR)and carcinogenesis of gastric cancer.Methods The expression of IGF-ⅠR was detected in 40 cases of resected gastric cancer tissues and adjacent normal gastric mucosa by immunohistochemistry.The expression of IGF-ⅠR in gastric cancer cell lines(MGC803 and SGC7901)was detected by Western Blot.siRNAs targeted to IGF-ⅠR were designed,synthesized and transfected into MGC803 cells,the changes of IGF-IR protein level were detected by Western Blot at 48 h after transfection,the cell proliferation was examined by MTT,and then the growth curve was obtained.Results The positive rate of IGF-IR expression in gastric cancer tissues was 75.5%,significantly higher than that of adjacent normal tissues (25%,P＜0.01).The expression level of IGF-IR was related with TNM stage,lymphnode metastasis (P＜0.05),but not related with sex,age,histological differentiation,invasion depth of gastric cancer (P＞0.05).Intense expression of IGF-ⅠR was showed in gastric cancer cell lines.The inhibition ratio of IGF-ⅠR expression in sigNAl group were 89.80%±4.10%,the cell proliferation decreased to mininlunl level at the fifth day aftertransfection(by 29.0%±4.0%of mock-treated group),the cell number decreased by 21.15%±1.10%of mock treated group at the same time.Conclusions IGF-ⅠR is over-expressed in gastric cancer cells and can be effectively silenced by RNA interferes,therefore the growth of tmnor cell Was inhibited.Thus,it indicates that IGF-ⅠR may be a promising target for gene therapy of gastric cancer.