中文摘要：

目的 ：探讨在肝细胞肝癌Huh-7细胞中前列腺素E2EP3各受体亚型对肿瘤细胞生长与侵袭的作用。方法：对常规培养的人肝细胞肝癌Huh-7细胞,瞬时转染EP3受体的4个亚型EP3-4R、EP3-5R、EP3-6R、EP3-7R,应用RT-PCR实验检测转染细胞EP3受体各亚型的m RNA表达水平;应用Western blot实验检测相关蛋白水平。对转染后的Huh-7细胞,分别给予不同浓度的EP3受体激动剂sulprostone作用24 h,用WST-8细胞增殖测定试剂检测细胞的增殖情况;应用划痕实验检测细胞的侵袭性;应用Western blot实验检测细胞内ERK蛋白磷酸化水平的变化。结果：RT-PCR及Western blot实验结果显示Huh-7细胞EP3受体表达水平明显增高。WST-8实验显示,经10μmol/L sulprostone处理24 h后,过表达EP3-4R、EP3-5R和EP3-7R亚型的细胞增殖率分别达到126.7%、124.0%、123.8%。划痕实验结果显示,过表达细胞的侵袭性分别增加到135.8%、123.5%、128.7%。Western blot显示,EP3-4R、EP3-5R和EP3-7R转染细胞内ERK磷酸化水平分别上调了54.8%、33.4%、44.3%。而过表达EP3-6受体亚型细胞的增殖率、侵袭率和胞内ERK磷酸化水平改变不明显。结论 ：Huh-7肝癌细胞中,EP3-4R、EP3-5R及EP3-7R这3种受体亚型对细胞的生长及侵袭有显著促进作用,而EP3-6R亚型则无明显的促进作用。EP3受体促进肝癌细胞生长和侵袭的作用与ERK激活的现象一致。

英文摘要：

Objective：To investigate the functions and mechanisms of EP3 receptor subtypes in promoting hepatoma Huh-7 cell growth and invasion. Methods：Human hepatocellular carcinoma Huh-7 ceils were transiently transfected with EP3-4, EP3-5, EP3-6 and EP3-7 receptor. The expression of EP3 receptor in the transfected cells was detected by RT-PCR and Western blot. The cells were treated with various concentrations of selective EP3 agonist sulprostone. Cell viability was detected in the transfected ceils by WST-8. Scratch test was performed to detect invasion ability in the transfected cells. Western blot was employed to detect the phosphorylation level of P-ERK. Results：The expression of EP3 receptor subtypes was markedly increased in the transfected cells by analysis of RT-PCR and Western blot. Under the treatment of 10μmol/L sulprostone for 24 hours, the cell growth rate of Huh-7 cells transiently transfected with EP3-4, EP3-5 and EP3-7 receptor was increased to 126.7%, 124.0%, and 123.8%, respectively. The growth of cell invasion rate separately came to 135.8%, 123.5%,and 128.7%. The concentration of intracellular P-ERK in Huh-7 cells over- expressed of EP3-4, EP3-5 and EP3-7 receptor increased by 54.8%, 33.4% ,and 44.3% individually after 30 minutes exposure of 10 p~mol/L sulprostone. However,over-expression of EP3-6 receptor cells had no significant difference in cell growth,cell invasion and the level of intracellular ERK phosphorylation. Conclusion： Our results suggest that EP3 receptor subtypes,including EP3-4, EP3-5 and EP3-7, mediate a great progress of the ability of proliferation and invasion in hepatocellular carcinoma Huh-7 cells, whereas EP3- 6 receptor does not. Additionally, the function of EP3 receptor in accelerating cell growth and invasion of Huh-7 cells is in line with the activation of ERK.