[Relationship between estradiol and the mitogenic activated protein kinase signal transduction pathway].

ABSTRACT

OBJECTIVE: To discuss the relationship between estradiol and the mitogenic activated protein kinase signal transduction pathway and the expression of the MAPK in the MCF-7 breast cancer cell-line. METHODS: Epithelial growth factor (EGF) and different concentration of estradiol to induce the expression of phosphospecific ERK1/2 (pERK1/2) in MCF-7 cell line was used and the expression of pERK1/2 with western-blotting was detected. Then antiestrogen ICI 182780 and MAPK inhibitor PD98059 to inhibit the expression of pERK1/2 was used. The cell cycle of MCF-7 was detected by FACS. RESULTS: EGF could significantly induce the expression of pERK1/2. Estradiol could also induce the expression of pERK1/2, but the intensity was less than the induction of EGF. The percentage of cells in the G(2)/M cell cycle after estradiol induction increased (18.38%) compared to the control group (10.52%) (P < 0.05). CONCLUSIONS: MAPK is an important regulatory signal in breast cancer. Its measurement in breast cancer tissues provides information about the degree of activation of various growth factor pathways. This molecule may also provide a molecular target for compounds designed to block cell proliferation.