Enhanced epidermal growth factor receptor signaling in MCF7 breast cancer cells after long-term culture in the presence of the pure antiestrogen ICI 182,780 (Faslodex)
Enhanced epidermal growth factor receptor signaling in MCF7 breast cancer cells after long-term culture in the presence of the pure antiestrogen ICI 182,780 (Faslodex)
复制标题
DOI：
10.1210/en.142.7.2776
复制
发表时间：
2001-07-01
期刊：
影响因子：
4.8
通讯作者：
Nicholson, RI
中科院分区：
文献类型：
--
作者：
McClelland, RA;Barrow, D;Nicholson, RI
本文描述了通过在类固醇耗尽、ICI 182,780 (Faslodex; 10(-7) M) 补充培养基中连续培养雌激素反应性亲代细胞系来建立抗雌激素耐药性 MCF7 乳腺癌细胞亚系 (FASMCF)。经过 3 个月的生长抑制期后，ICI 182,780 中的细胞开始增殖，增殖速度与未处理的野生型细胞相似。免疫细胞化学显示这些细胞的雌激素受体减少，并且缺乏孕激素受体蛋白。 RT-PCR 和雌激素反应元件报告构建体的瞬时转染研究证实 ICI 182,780 抑制了雌激素反应元件介导的信号传导。 FASMCF 细胞对表皮生长因子受体 (EgfR)/丝裂原激活蛋白激酶 (MAPK) 介导的信号传导的依赖性增强。因此，EgfR 蛋白和信使 RNA、对转化生长因子-a 的生长反应以及细胞外信号调节激酶 1/2 MAPK 激活水平均增加。与野生型细胞不同，FASMCF 细胞对 EgfR 特异性酪氨酸激酶抑制剂 (TKI)、ZD1839（易瑞沙）和 MEK1 激活抑制剂 (MAPKK)、PD098059 的生长抑制高度敏感。短期（大约 3 周）停止使用抗雌激素对细胞的生长或表型没有影响，而长期停止使用抗雌激素对细胞的生长或表型没有影响。 停药（> 10周）似乎部分逆转了细胞表型，雌激素受体增加，FgfR水平降低。在随后的研究中，FASMCF细胞维持在TKI中，其生长再次受到抑制，并且在初始ICI 182,780耐药出现的3个月内未能出现继发性TKI耐药。此外，同样维持在ICI 182,780和TKI组合治疗条件下的野生型细胞仍然生长停滞（>6个月），通过降低细胞增殖率和增加细胞死亡而导致显着的细胞损失。
This paper describes the establishment of an antiestrogen-resistant MCF7 breast cancer cell subline (FASMCF) by continuous culture of the estrogen-responsive parental line in steroid-depleted, ICI 182,780 (Faslodex; 10(-7) M)-supplemented medium. After a 3-month period of growth suppression, cells began to proliferate in ICI 182,780 at rates similar to those of untreated wild-type cells. Immunocytochemistry showed these cells to have reduced estrogen receptor and an absence of progesterone receptor proteins. RT-PCR and transient transfection studies with estrogen response element-reporter constructs confirmed that ICI 182,780-suppressed estrogen response element-mediated signaling. FASMCF cells show increased dependence upon epidermal growth factor receptor (EgfR)/mitogen-activated protein kinase (MAPK)-mediated signaling. Thus, EgfR protein and messenger RNA, growth responses to transforming growth factor-a, and extracellular signal-regulated kinase 1/2 MAPK activation levels are all increased. Unlike wild-type cells, FASMCF cells are highly sensitive to growth inhibition by an EgfR-specific tyrosinekinase inhibitor (TKI), ZD1839 (Iressa), and an inhibitor of the activation of MEK1 (MAPKK), PD098059.Short-term (similar to3 weeks) withdrawal of cells from antiestrogen had no effect on growth or phenotype, whereas longer withdrawal(> 10 weeks) appeared to partially reverse the cellular phenotype with increasing estrogen receptor and decreasing FgfR levels.In subsequent studies FASMCF cells were maintained in TKI, where their growth was again suppressed and secondary TKI resistance failed to develop within the 3-month period in which initial ICI 182,780 resistance arose. Furthermore, wild-type cells similarly maintained in combination ICI 182,780 and TKI treatment conditions remained growth arrested (>6 months), with notable cell loss through both reduced rates of cellular proliferation and increased cell death.