Chen Wei-Juan, Wang Hui, Tang Yong, Liu Chuan-Liang, Li Hong-Li, Li Wen-Tong
Department of Pathology, Weifang Medical University, Weifang, Shandong 261041, PR China.
Chin J Cancer. 2010 Feb;29(2):151-7. doi: 10.5732/cjc.009.10447.
Epithelial-mesenchymal transition (EMT) not only initiates invasion and metastasis of tumors, but also induces multidrug resistance in tumor cells. Our experiment analyzed the dependability between breast cancer resistant protein (BCRP) and EMT in breast cancer to explore the effect of EMT on BCRP-mediated multidrug resistance.
The expressions of BCRP and transcription inhibitor Snai1 (Snail) in breast cancer were detected by immunohistochemistry. The eukaryotic expression vector pCDNA3.1-Snail was constructed and then transfected into human breast cancer cell line MCF-7. Snail, epithelial marker gene E-cadherin, interstitial marker gene Vimentin, multidrug resistance protein BCRP, and relative drug resistance were measured by immunofluorescence, Western blot, real-time polymerase chain reaction (PCR), and MTT assay.
Immunohistochemistry showed that Snail was highly correlated with BCRP in breast cancer. Immunofluorescence, Western blot, real-time PCR revealed that compared with parent cell MCF-7, after transfected with Snail, the expression of E-cadherin in MCF-7 decreased, but Snail, Vimentin, and BCRP increased. MTT displayed that the relative drug resistance increased to 9.93.
After transfected with eukaryotic expression vector pCDNA3.1-Snail, breast cancer cells MCF-7 showed EMT with BCRP-mediated multidrug resistance.
上皮-间质转化（EMT）不仅启动肿瘤的侵袭和转移，还诱导肿瘤细胞产生多药耐药性。我们的实验分析了乳腺癌耐药蛋白（BCRP）与乳腺癌中EMT之间的相关性，以探讨EMT对BCRP介导的多药耐药性的影响。
采用免疫组织化学法检测乳腺癌中BCRP和转录抑制因子Snai1（Snail）的表达。构建真核表达载体pCDNA3.1-Snail，然后转染人乳腺癌细胞系MCF-7。通过免疫荧光、蛋白质印迹法、实时聚合酶链反应（PCR）和MTT法检测Snail、上皮标记基因E-钙黏蛋白、间质标记基因波形蛋白、多药耐药蛋白BCRP及相对耐药性。
免疫组织化学显示，乳腺癌中Snail与BCRP高度相关。免疫荧光、蛋白质印迹法、实时PCR显示，与亲本细胞MCF-7相比，转染Snail后，MCF-7中E-钙黏蛋白表达降低，但Snail、波形蛋白和BCRP表达增加。MTT法显示相对耐药性增加至9.93。
真核表达载体pCDNA3.1-Snail转染后，乳腺癌细胞MCF-7表现出具有BCRP介导的多药耐药性的EMT。
