外源性胰岛素样生长因子结合蛋白7抑制人乳腺癌MDA-MB-453细胞的增殖  

Inhibitory effect of exogenous insulin-like growth factor binding protein 7 on proliferation of human breast cancer cell line MDA-MB-453 and its mechanism

作　　者：袁磊[1] 范文娟[1] 杨旭光[1] 饶淑梅[1] 宋金玲[1] 宋国华[1] 

机构地区：[1]漯河医学高等专科学校分子生物学实验室,漯河462002

出　　处：《生理学报》2013年第5期519-524,共6页Acta Physiologica Sinica

基　　金：supported by Natural Science Research Project of Luohe Medical College;China(No.2010-S09;2013-S-LMC02)

摘　　要：为了探究外源性胰岛素样生长因子结合蛋白7(insulin-1ike growth factor binding protein 7,IGFBP7)对人乳腺癌MDAMB-453细胞增殖的影响及其分子生物学机制,本研究通过四甲基偶氮唑蓝(MTT)实验揭示外源性IGFBP7对人乳腺癌MDAMB-453细胞增殖有显著的抑制作用(IGFBP7的IC_(50)=8.49μg/mL),并呈剂量和时间的双重依赖性,该作用可被p38^(MAPK)阻断剂SB203580抑制。流式细胞术检测结果表明,外源性IGFBP7可有效阻止MDA-MB-453细胞从G1期进入S期。Western blot进一步检测了外源性IGFBP7对p38^(MAPK)、p-p38^(MAPK)、p21^(CIPI/MAFI)、Rb和p-Rb蛋白水平的影响。外源性IGFBP7可促进p38^(MAPK)磷酸化和p21^(CIPI/WAFI)蛋白的表达,抑制Rb磷酸化,而SB203580能够抑制外源性IGFBP7对人乳腺癌MDA-MB-453细胞p21^(CIPI/WAFI)蛋白表达和Rb磷酸化的影响。以上结果表明,外源性IGFBP7可通过激活p38^(MAPK)信号通路,上调p21^(CIPI/WAFI)蛋白表达和抑制Rb磷酸化,以阻滞人乳腺癌MDA-MB-453细胞于G1期。The present study was to investigate the effects of exogenous insulin-like growth factor binding protein 7 （IGFBP7） on the proliferation of human breast cancer cell line MDA-MB-453 and its possible mechanism. By means of MTT method in vitro, the results showed exogenous IGFBP7 inhibited the growth of MDA-MB-453 cells （IC50 of IGFBP7 = 8.49 ~tg/mL） in time- and concentration-dependent manner. SB203580, p38MAPK inhibitor, blocked the anti-proliferative effect of exogenous IGFBP7. The flow cytometry assay showed that exogenous IGFBP7 remarkably induced G0/G1 arrest in MDA-MB-453 cells. The Western blot showed that exogenous IGFBP7 promoted phosphorylation of p38MAPK, up-regulated expression of p21C^PI/WAFI, and inhibited phosphorylation of Rb. SB203580 restrained exogenous IGFBP7-indueed regulation of p21cIP1/wAF1 and p-Rb in MDA-MB-453 cells. In conclusion, the present study suggests that exogenous IGFBP7 could activate the p38rcaPK signaling pathway, upregulate expression, inhibit phosphorylation of Rb, and finally induce G0/GI arrest in MDA-MB-453 ceils.

关 键 词：胰岛素样生长因子结合蛋白7 MDA—MB-453 细胞增殖 P38MAPK p21CIPI WAF1 

分 类 号：R737.9[医药卫生—肿瘤]