Regulation of human progesterone receptor isoforms A and B in uterine endometrial carcinoma by estrogen and insulin-like growth factor-1

目的通过研究雌激素、胰岛素样生长因子(IGF)-I对子宫内膜癌孕激素受体亚型A和B的调控作用,探讨孕激素对子宫内膜癌的作用机制及影响因素,为临床孕激素治疗子宫内膜癌提供理论依据.方法对体外培养子宫内膜癌细胞系HEC-IB和乳腺癌细胞系MCF-7,分别给予雌二醇(E2)10 nmol/L和IGF-I 20 ng/ml作用3 d,用Western印迹方法观察两种孕激素受体亚型的蛋白质含量变化;从细胞中提取RNA,通过逆转录-多聚酶链反应(RT-PCR),观察孕激素受体B亚型的mRNA水平的调控.结果 (1)Western印迹试验显示,HEC-IB细胞给予E2作用72 h后,人孕激素受体(hPR)-A、hPR-B光密度值用药前后差异无显著意义,P=0.716,P=0.391.给予IGF-I作用72 h,hPR-A、hPR-B明显下调(P=0.008,P=0.002).(2)RT-PCR显示,HEC-IB细胞中hPRB mRNA未见表达,给予10 nmol/L雌激素刺激72 h后,hPRB mRNA阳性,呈上调作用;经IGF-I 20 ng/ml作用后,hPRB mRNA阳性,IGF-I对其有上调作用,但IGF-I的上调作用弱于雌激素.MCF-7细胞中hPRB mRNA未见表达,经10 nmol/L雌激素刺激72 h后,hPRB mRNA阳性,呈上调作用,但雌激素对hPRB mRNA的上调作用在MCF-7细胞中弱于HEC-IB细胞.结论 (1)E2和IGF-I对hPR亚型均有调控作用,且具有不同组织细胞特异性.(2)E2和IGF-I在基因水平或转录水平使hPRB mRNA上调,但在转录后可能存在某种抑制因素使hPRB蛋白质产生受到抑制.To investigate the regulation of human progesterone receptor isoforms A and B in uterine endometrial carcinoma by estrogen and insulin-like growth factor-1 (IGF-I) so as to provide theoretical basis for clinical hormone treatment of uterine endothelium cancer.The uterine endometrial adenocarcinoma cell line HEC-IB and the breast cancer cell line MCF-7 were cultured in vitro. The HEC-IB cells were stimulated by 10 nmol/L estrogen and 20 ng/ml IGF-I respectively for 72 h. The MCF-7 cells were stimulated by 10 nmol/L estrogen for 72 h. Western blotting was used to examine the protein levels of the two isoforms of receptors of progesterone. RNA was extracted from the cells. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the mRNA levels of the isoform B.(1) Western blotting showed that the photodensity values of hPRA and hPRB did not change significantly after the HEC-IB cells were stimulated by estrogen for 72 hours (P = 0.716, and 0.391 respectively), however, the hPRA and hPRB were significantly down-regulated after IGF-I had been given for 72h (P = 0.008 and 0.002 respectively). After MCF-7 cell was given estrogen for 72 h hPR-A tended to be up- regulated but this change had no significant difference (P = 0.074) however, hPRB was significantly up- regulated (P = 0.044). (2) RT-PCR showed that hPRB mRNA was not expressed in HEC-IB cells originally, and became positive after stimulation by estrogen and IGF-1 for 72 hours respectively, however, the expression level being higher in the HEC-IB cells stimulated by estrogen than in those stimulated by IGF-1. hPRB was not expressed in MCF-7 cells originally too, and became positive after simulation by estrogen and IGF-1 for 72 hours respectively, however, the expression level being higher in the MCF-7 cells stimulated by estrogen than in those stimulated by IGF-1.(1) Estrogen and IGF-I regulate hPR isoforms and have cell specialty. (2) Estrogen and IGF-I up- regulate hPRB mRNA at gene level or transcription level, but there are some inhibitory factors which make the protein production become less after transcription.高等学校博士学科点专项科研项目PubMed中文核心期刊要目总览(PKU)中国科学引文数据库(CSCD)012836-8398