醋酸棉酚对人舌鳞癌Tca8113细胞生长及人类错配修复基因1甲基化水平的影响

目的 研究醋酸棉酚（ GAA）对人舌鳞癌 Tca8113细胞增殖的影响和对人类错配修复基因 1（hMLH1）甲基化水平的影响，初步探讨其抗肿瘤机理。方法 应用 MTT法检测 GAA对Tca8113细胞生长的影响；应用巢式甲基化特异性聚合酶链反应（nMSP）检测 Tca8113细胞在 GAA作用 48、72 h后hMLH1基因甲基化状态的改变情况。结果 MTT检测显示，作用 24~72 h，GAA对Tca8113细胞生长具有抑制作用；nMSP检测显示，以终浓度 30、15 μmol?L-1的GAA作用于 Tca8113细胞 48、72 h后， hMLH1基因甲基化条带的平均光度值降低，与未经药物处理组比较差异有统计学意义（P<0.05）。结论 GAA能抑制舌鳞癌细胞的生长，并能降低 hMLH1基因的甲基化水平。 GAA去甲基化作用可能是其具有抗肿瘤作用的机制之一。

Effects of gossypol acetic acid on the proliferation and methylation level of the human MutL homologue 1 gene in human tongue carcinoma cell line Tca8113

 Objective  This paper aims to study the effects of gossypol acetic acid (GAA) on proliferation and methylation level of human MutL homologue 1 (hMLH1) gene in human tongue cancer cell line Tca8113. Methods The MTT assay was used to determine the effects of the acid on the proliferation inhibition in Tca8113 cells treated with different GAA concen-trations. Nested methylation-specific polymerase chain reaction (nMSP) was used to detect the change in the methylation level of hMLH1 after 48 and 72 h with 30 and 15 μmol•L-1 GAA treatment. Results  MTT assay results showed the growth and proliferation inhibition of Tca8113 cells in the experimental GAA group after 24h to 72 h of GAA treatment. The nMSP results indicated that the average optical density of hMLH1 in the Tca8113 cells significantly changed after the GAA treat-ment (30 μmol•L.1 GAA for 48 h and 15 μmol•L.1 for 72h) (P<0.05) compared with that of the control group. Conclusion  GAA does not only inhibit Tca8113 proliferation but also has a demethylation effect on the hMLH1 gene. These phenomena may be part of an underlying tumor-suppression mechanism of GAA.