Gene cloning of the novel molecules associated with the differentiation of adenocarcinoma and the development of the molecular target therapy

从原发部位不明的腹膜癌患者的腹水中建立了一株人腺癌细胞TAKA-1。TAKA-1在裸小鼠体内具有高度致瘤性，并在体外以球形单细胞的形式生长。用去甲基化剂5-aza-2'-脱氧胞苷处理TAKA-1细胞，诱导其形态发生明显变化，从漂浮的球形细胞变为贴壁上皮细胞。5-氮杂-2′-脱氧胞苷也可诱导G1/S阻滞导致衰老。细胞周期蛋白依赖性激酶抑制剂（p161NK4a、p19INK4d和p21CIP1/WAF1）、促凋亡蛋白（BAD、DAP-kinase和lipocalin 2）和整合素介导的信号传导相关蛋白（integrin α 3、7b、9、integrin bwta 4,7、rho/rac GEF、rhoC、zyxin、MUC18） mRNA水平上调，而细胞周期蛋白（cyclin D1、D3、A、C）和抗凋亡蛋白（survivin） mRNA水平下调。据我们所知，在DNA去甲基化后，没有细胞系的形态学变化像TAKA-1那样显著。TAKA-1为进一步研究腹膜癌的分子机制和高效筛选新的DNA去甲基化剂提供了良好的实验模型。

A human adenocarcinoma cell line, TAKA-1, was established from ascites of a patient with peritoneal carcinomatosis of unknown primary site. TAKA-1 is highly tumorigenic in athymic nude mice and grows in suspension oas spherical single cells in vitro. Treatment of TAKA-1 cells with demethylating agent, 5-aza-2'-deoxycytidine, induced marked change in morphology from floating spherical to adherent epithelial. Treatment with 5-aza-2'-deoxycytidine also induced G1/S arrest leading to senescence. The cyclin-dependent kinase inhibitors (p161NK4a, p19INK4d and p21CIP1/WAF1), proapoptotic proteins (BAD, DAP-kinase and lipocalin 2) and proteins involved in integrin-mediated signaling (integrin alpha 3, 7b, 9, integrin bwta 4, 7, rho/rac GEF, rhoC, zyxin, MUC18) was up-regulated at mRNA level, while cyclines (cyclin D1, D3, A, C) and anti-apoptotic protein such as survivin was down-regulated at mRNA level after this treatment. To our knowledge, no cell lines have been reported which change in morphology so markedly as TAKA-1 after demethylation of DNA. TAKA-1 should provide a good experimental model to further study the molecular mechanism of peritoneal carcinomatosis and to efficiently screen new demethylating agents of DNA.