PTEN及mTOR在人肺腺癌培美曲塞耐药株A549/PEM中的表达

The expression and significance of PTEN and mTOR in A549 and pemetrexed-resistant human lung adenocarcinoma cancer cell line A549

目的:应用高浓度反复间歇法建立人肺腺癌A549培美曲塞耐药细胞株A549/PEM,探讨PTEN、m TOR在人肺腺癌亲本株A549及培美曲塞诱导人肺腺癌耐药株A549/PEM中的表达变化。方法:采用终浓度为500ng/ml的培美曲塞反复间歇冲击建立人肺腺癌A549培美曲塞耐药细胞株A549/PEM,MTT法检测细胞耐药性。RT-PCR、Western blot分别检测PTEN、m TOR在A549及A549/PEM细胞的mRNA及蛋白表达变化。结果:A549/PEM耐药指数为26.87±1.81,较亲本株A549升高约27倍。RT-PCR检测mRNA表达示A549/PEM的PTEN及m TOR基因表达与A549相比均表达上调(P=0.023;P<0.01);Western blot检测蛋白表达示A549/PEM的PTEN及m TOR蛋白表达与A549相比均表达上调(P<0.01;P=0.04)。结论:高浓度反复间歇法可成功建立人肺腺癌A549培美曲塞耐药细胞株模型;PTEN、m TOR表达变化可能与培美曲塞获得性耐药相关。

Objective：To establish the pemetrexed-resistant human lung adenocarcinoma cancer cell line A549 by exposing lung adenocarcinoma cancer cell line A549 with repeatedly high-level concentration of pemetrexed,and investigate the expression of PTEN and mTOR in normal lung adenocarcinoma cancer cell line A549 and pemetrexed-resistant human lung adenocarcinoma cancer cell line A549/PEM.Methods：The pemetrexed-resistant human lung adenocarcinoma cancer cell line A549/PEM was established by exposing pemetrexed with repeatedly to high-level concentration of 500ng/ml for 1h each time.The drug resistant index（RI） was detected by MTT.The expression of PTEN and mTOR in A549 and A549/PEM were detected by RT-PCR and Western blot.Results：The value of resisitant index of A549/PEM was elevated more than 27 times,the number was 26.87±1.81.Over-expression mRNA and protein of PTEN in A549/PEM were detected by RT-PCR and Western blot（P=0.023,P〈0.01）.Over-expression mRNA and protein of mTOR in A549/PEM was detected by RT-PCR and Western Blot （P〈0.01;P=0.04）.Conclusion：The pemetrexed-resistant human lung adenocarcinoma cancer cell line A549 can be established by repeated exposing to high-level concentration of pemtrexed successfully.The variation of PTEN and mTOR may be connected with lung adenocarcinoma pemetrexed acquired drug resistance.