Yang Deqi, Wang Shan, Wang Shu, Ye Yingjiang, Cui Zhirong
Laboratory of Surgical Oncology, Peking University People's Hospital, Beijing 100044, China.
Zhonghua Yi Xue Za Zhi. 2002 Sep 25;82(18):1232-4.
To investigate the effect of mitogen-activated protein kinase (MAPK) signal cascade in the non-estrogen antagonistic mechanism of tamoxifen (TAM).
Human breast cancer cells MCF-7 were cultured. TAM, PD98075, inhibitor of MAPK kinase (MEK), or TAM + PD98075 was added into the culture media, followed by methyl thiazolyl tetrazolium (MTT) and DMSO. Then the 542nm absorption value was measured and the growth curve was drawn. Western blot was used to measure the expression of p-extracellular signal-regulated kinase (ERK) in MCF-7 cells. Flow cytometry was applied to analyze the cell cycle and apoptosis.
The optical density representing the relative expression of p-ERK was lower successively in the control, TAM, PD09875, and TAM + PD09875 groups. The apoptotic rate of MCF-7 cells was 6.44%, 8.3%, 36.5% and 53.5% in the control, PD98075, TAM, and TAM + PG98075 groups respectively The rate of cells in G(0)G(1) phase was 74.25%, 79.76%, 84.02%, and 95.82% in those groups respectively. Ther rate o cells in S phase was 21.03%, 15.22%, 11.43%, and 2.22% respectively in those groups. The rate of cells in G(2)M phase was 4.71%, 5.02%, 4.52%, and 1.96% respectively in those groups.
MAPK signal transduction pathway plays a certain role in the non-estrogen antagonistic mechanism of tamoxifen.
探讨丝裂原活化蛋白激酶（MAPK）信号级联在他莫昔芬（TAM）非雌激素拮抗机制中的作用。
培养人乳腺癌细胞MCF-7。将TAM、MAPK激酶（MEK）抑制剂PD98075或TAM + PD98075加入培养基中，随后加入甲基噻唑基四氮唑（MTT）和二甲基亚砜（DMSO）。然后测量542nm处的吸光度值并绘制生长曲线。采用蛋白质免疫印迹法检测MCF-7细胞中磷酸化细胞外信号调节激酶（p-ERK）的表达。应用流式细胞术分析细胞周期和凋亡情况。
代表p-ERK相对表达的光密度在对照组、TAM组、PD09875组和TAM + PD09875组中依次降低。对照组、PD98075组、TAM组和TAM + PG98075组中MCF-7细胞的凋亡率分别为6.44%、8.3%、36.5%和53.5%。这些组中处于G(0)G(1)期的细胞率分别为74.25%、79.76%、84.02%和95.82%。这些组中处于S期的细胞率分别为21.03%、15.22%、11.43%和2.22%。这些组中处于G(2)M期的细胞率分别为4.71%、5.02%、4.52%和1.96%。
MAPK信号转导通路在他莫昔芬的非雌激素拮抗机制中起一定作用。
