内皮素在培养的肝癌细胞中的表达及其作用

 目的：确定人肝癌细胞合成释放内皮素（ET）与否；探讨外源性ET-1对培养的人肝癌细胞增殖的影响。方法：应用特异性放射免疫分析法测定肝癌细胞（HCC9204和SMMC7721）培养液中ET-1含量；采用3H-胸腺嘧啶核苷（3H－TdR）掺入和液体闪烁技术观察ET－1（10^－11～10^－7mol／L）对培养的加或不加表皮生长因子（EGF）的肝癌细胞增殖的影响。结果：培养的肝癌细胞HCC9204和SMMC7721均能分泌ET－1，并呈时间依赖性。培养24h为分泌高峰期，HCC9204和SMMC7721在有血清条件下ET-1浓度分别为86．38±7．7Pg／ml，76．32±8．4pg／ml，均显著高于各自无血清组（28．16±3．34pg／ml，23．22±4．72pg／ml）（P＜0．01）。ET－1单独作用对肝癌细胞DNA合成没有影响（P＜0．05）；在EGF（1nmol／L）存在时，ET－1在10^－11～10^－17mol／L时DNA合成增殖率为27．4％～86．6％（P＜0．05），且呈剂量依赖性（γ=0．7531，P＜0．05）。结论：人肝癌细胞可合成并分泌ET；ET－1单独作用对肝癌细胞DNA合成没有影响，但能明显增强EGF对肝癌细胞的增殖作用。

Production and secretion of endothelin by cultured hepatoma cells and its functions

PURDOSE: To evaluate whether endothelin (ET) can be synthesized by and released from human hepatoma cells. and whether ET Stimuates Proliferation of the tumor cells. METHODS: By using a specific ET-1 radioimmunoassay, ET-1 was detected in the conditioned media from HCC9204 cells and SMMC7721 cells. ET-1 (10-10~10-7mol/L) was added to cultures of HCC9204 cells with or without epidemal growth factor (EGF) and Proliferation rates of the cells were measured with (3H]-thymidine incorporation and liquid scintillation techniques. RESULTS: ET1 was released from both HCC9204 and SMMC7721 cells as a function of time,reaching a plateau after 24h. CONCLUSION: Human hepatoma cells may produce and Secrete ET.ET-1 alone didn't stimulate DNA synthesis in the cells. But ET-1 Potentiated markedly DNA Synthesis stimulated by EGF.