膀胱癌中内皮素作用的研究

应用Ｎｏｒｔｈｅｒｎｂｌｏｔ杂交技术及放射免疫方法对人膀胱移行细胞癌组织中内皮素－１ｍＲＮＡ及内皮素活性分子的表达水平进行检测，研究了佛波酯对人膀胱移行细胞癌ＢＩＵ－８７细胞中内皮素活性分子表达水平的调节作用，并探讨了内皮素抗血清及内皮素Ａ型受体竞争性拮抗剂ＢＱ_（１２３）对ＢＩＵ－８７细胞ＤＮＡ合成的影响。结果表明，人膀胱移行细胞癌组织中内皮素－ｌｍＲＮＡ及内皮素活性分子的表达水平明显高于相应的癌旁组织，佛波酯可促进ＢＩＵ－８７细胞合成和分泌内皮素，内皮素抗血清及ＢＱ_（１２３）可抑制ＢＩＵ－８７细胞合成ＤＮＡ。提示内皮素在膀胱癌发展及ＢＩＵ－８７细胞恶性增殖中可能起重要作用。

The Effect of Endothelin On the Proliferation of Bladder Cancer Cells

Endothelin(ET)is a potent vasocontrictor peptide released from vascular endothelial cells.ET also has other biological functions relevant to tumorgenesis,including mitogenic and angiogenic activities. The expression of ET in human bladder cancer tissues and bladder cancer BIU-87 cell line was detected,and the effect of ET on the proliferation of BIU-87 was studied. Northern blot showed that the level of ET-1 mRNA expression was more than 4-fold higher in tumor tissues than the surrounding noncancerous tissues (n=4).Using radioimmunoassay,it was also found that the content of ET in tumor tissues was 6-8 fold higher than the surrounding noncancerous tissues (n=4). In BIU-87 cells, the level of ET concentration was increased (38%and 47%) after TPA (100 ng/mL) treatment (4 h and 8 h). The secretion level of ET in BIU-87 cells was also slightly stimulated by TPA (100 ng/mL,8 h). After treated with ET-antiserum,the ￣3H-TdR incorporation was markedly decreased (57%) in BIU-87 cells whereas it was also decreased (35%) after treated BIU-87 with ET receptor A antagonist──BQ_(123).In conclusion,ET was markedly expressed both in human bladder cancer tissues and BIU-87 cells, especially when the cells were induced by TPA. It seems that ET has proliferative effgct on bladder cancer cells and this effect can be depressed by ET-antiserun or ET receptor A antagonist──BQ_(123).