IGF-1R基因通过调控BMP2表达影响SMMC7721细胞的增殖和凋亡  

Silencing IGF-1R gene inhibits proliferation of human SMMC7721 cell and promotes its apoptosis through down-regulating BMP2 expression

作　　者：傅敬忠 黄龙璋 于强 储节胜 匡美波 徐冠军 

机构地区：[1]江西省九江市第三人民医院肿瘤科,江西九江332000 [2]江西省修水县第一人民医院肿瘤科,江西修水332400

出　　处：《中国癌症杂志》2016年第4期297-302,共6页China Oncology

摘　　要：背景与目的:胰岛素生长因子-1(insulin-like growth factor-1,IGF-1)是一种重要的肽类激素,通过与其受体(IGF-1 receptor,IGF-1R)和胰岛素受体(insulin receptor,IR)结合并激活下游信号通路发挥生物学作用,骨形态发生蛋白(bone morphogenetic proteins,BMPs)因可促进多种肿瘤细胞的增殖和侵袭而日益成为肿瘤分子研究领域的热点。该研究通过RNA干扰(RNAi)技术沉默IGF-1R基因,探讨其对肝癌SMMC7721细胞中BMP2表达的影响以及对细胞增殖和凋亡的影响。方法:构建靶向IGF-1R基因的RNAi真核表达质粒,转染至肝癌SMMC7721细胞,用反转录聚合酶链式反应(reverse transcription-polymerase chain reaction,RT-PCR)和蛋白[质]印迹法(Western blot)检测IGF-1R和BMP2基因表达抑制效应,MTT实验检测IGF-1R基因沉默后细胞生长曲线,流式细胞术检测IGF-1R基因沉默后细胞凋亡情况。结果:成功构建靶向IGF-1R基因的真核表达质粒,IGF-1R-si RNA-1和IGF-1R-si RNA-2转染至肝癌SMMC7721细胞后,对IGF-1R基因的m RNA抑制效率分别达到68.9%和80.7%(P<0.05),对BMP2基因的m RNA抑制效率分别达到79.5%和83.3%(P<0.05),对IGF-1R蛋白表达抑制率分别为46.1%和62.1%,对BMP2蛋白表达抑制率分别为42.5%和60.9%(P<0.05)。根据MTT实验结果,绘制的生长曲线显示,IGF-1R基因沉默后SMMC7721细胞增殖速率明显低于对照组(P<0.05),细胞凋亡比例高于对照组(P<0.05)。结论:IGF-1R基因沉默表达能介导BMP2基因不同水平下调表达,抑制SMMC7721细胞增殖,并促进细胞发生凋亡。Background and purpose： Insulin-like growth factor-1 （IGF-1） is a peptide that participates in many biological processes by stimulating the downstream signaling pathways through their interaction with IGF-1 receptor （IGF-1R） and insulin receptor （IR）. Bone morphogenetic proteins （BMPs） are a group of functional proteins which participate in the biological processes of proliferation and migration in many kinds of cancers and have become a hot area of cancer research. The study aimed to investigate the effects of silencing IGF-1R gene on the expression level of BMP2 gene, and the cell proliferation and apoptosis of SMMC7721 cells. Methods： The RNAi plasmid targeting IGF-1R gene was constructed and transfected into SMMC7721 cells. Then the inhibition effect on the expression level of IGF-1R and BMP2 gene was detected by reverse transcription-polymerase chain reaction （RT-PCR） and Western blot. The SMMC7721 growth curve and cell apoptosis were detected by MTT assay and flow eytometry after they were transfected with RNAi plasmid. Results： The RNAi plasmid targeting IGF-1R gene was constructed successfully. The inhibition efficiencies at mRNA expression levels were 68.9% and 80.7% （IGF-1R gene）, 79.5% and 83.3% （BMP2 gene）, respectively, after transfection with IGF-1R-siRNA-1 and IGF-1R-siRNA-2 plasmid （P〈0.05）. The inhibition efficiencies at protein levels were 46.1% and 62.1% （IGF-1R gene, P〈0.05）, 42.5% and 60.9% （BMP2 gene, P〈0.05）, respectively. The results of MTF growth curve showed that the proliferation rate in the transfected SMMC7721 cells was significantly slower than that in the control group （P〈0.05）. The proportion of apoptotic ceils in transfected groups was significantly higher than that in the control group （P〈0.05）. Conclusion： Silencing IGF-1R gene can downregulate the expression of BMP2 gene at different levels that results in inhibition of cell proliferation and promotion of apoptosis in SMMC7721 cells.

关 键 词：IGF-1R基因 BMP2基因 肝癌SMMC7721细胞 细胞增殖 细胞凋亡 

分 类 号：R735.7[医药卫生—肿瘤]