三苯氧胺耐药乳腺癌细胞中表皮生长因子受体信号通路的研究  

Epidermal growth factor receptor signaling pathway in tamoxifen-resistant breast cancer cells

作　　者：甄林林[1] 朱旬[1] 郑伟[1] 王萱仪[1] 武正炎[1] 

机构地区：[1]南京医科大学第一附属医院乳腺外科,210029

出　　处：《中华普通外科杂志》2006年第6期446-448,共3页Chinese Journal of General Surgery

摘　　要：目的研究激素依赖性乳腺癌细胞在内分泌治疗中产生耐药的机制。方法选择雌激素受体(estrogen receptor,ER)阳性的乳腺癌细胞MCF-7,建立三苯氧胺(tamoxifen,TAM)耐药细胞(TAM-R)。采用荧光定量逆转录-聚合酶链反应(fluorescent quantitation reverse transcription- polymerase chain reaction,fqRT-PCR)、免疫印迹技术和四甲基偶氮唑蓝(MTF)比色法,分析MCF-7和TAM-R细胞中表皮生长因子受体(epidermal growth factor receptor,EGFR)、细胞外信号调节激酶(extracellular signal-regulated kinase,ERKs)和ER的变化,以及两种细胞对EGFR抑制剂的反应。结果MCF-7细胞持续给予TAM 10^(-7)mol/L处理6个月后,建立了TAM耐药细胞模型。与MCF-7细胞比较,TAM-R细胞中EGFR的mRNA表达水平增高,EGFR和p-ERK1/2蛋白表达增加,而ERK1/2总蛋白和ER蛋白表达水平差异无显著性,TAM-R细胞中EGFR信号通路的活性水平提高。TAM-R细胞对EGFR抑制剂更为敏感。结论长期TAM作用下的乳腺癌细胞,可通过EGFR信号通路的活性改变而对内分泌治疗产生耐受。EGFR抑制剂将有利于提高内分泌治疗的效果。Objective To study drug-resistant mechanism of hormonal dependent breast cancer cells in endocrine therapy. Methods Estrogen receptor （ER） positive breast cancer MCF-7 cells were subjected to the exposure of tamoxifen （TAM） for six months. And the model of TAM-resistant cell line （TAM-R） was established. Fluorescent quantitation reverse transcription-polymerase chain reaction （fqRT- PCR）, immunoblotting assay and cell growth inhibition test （MTT） were applied to investigate the expression of epidermal growth factor receptor （EGFR） mRNA, the proteins of EGFR, ER, extracellular signal-regulated kinas （ERKs） and phosphorylation-ERKs （p-ERKs）, and the effect of EGFR inhibitor on MCF-7 and TAM-R cells, respectively. Results TAM-resistant cell lines was established from MCF-7 cells under exposure to TAM （ 10^-7 mol/L） for more than six months. Compared with MCF-7 cells, the expression of EGFR mRNA was 4. 5-fold as strong, and proteins of EGFR and p-ERK1/2 increased significantly in the TAM-R cells. The total ERK1/2 and ER proteins expression was not different between the two cell lines. TAM-R cells were more sensitive to EGFR inhibitor than MCF-7 cells. Conclusion ER （ ＋ ） MCF-7 cells, when under long term exposure to TAM, could be resistant to anti-endocrine therapy by altering the activity of EGFR signaling pathway. EGFR inhibitors might increase the therapeutic effects on the breast cancer cells in endocrine therapy.

关 键 词：乳腺肿瘤 他莫昔芬 内分泌治疗 受体 表皮生长因子 

分 类 号：R737.9[医药卫生—肿瘤]