Transfecting a GPR30 antisense expression vector in both endometrial cancer cell lines, OHT was no longer able to induce growth effects, whereas the proliferative response to E2 was completely abrogated only in HEC1A cells.
GPR30 represents an alternative estrogen-responsive receptor that is overexpressed in tumors where estrogen and progesterone receptors are downregulated, and in high-risk endometrial cancer patients with lower survival rates.
We evaluated the expression of Gankyrin in endometrial tissues and further explored its roles in estrogen-driven and GPR30-mediated endometrial cancer cell proliferation.
E2 stimulated cell proliferation and induced GPR30 expression and PI3K/Akt pathway activation in endometrial cancer cells, Ishikawa cells, and HEC-1A cells, whereas the expression of ERs remained unchangeable.
Herein, we demonstrate that phosphorylation of focal adhesion kinase (FAK) is involved in cell migration induced by estradiol, tamoxifen and G1 (a GPR30 agonist) through the transmembrane ER (GPR30) in endometrial cancer cell lines with or without ERα (Ishikawa and RL95-2).
In addition, the results suggest that miR-424 up-regulation inactivated the PI3K/AKT signaling, which was mediated by G-protein-coupled estrogen receptor-1 (GPER) in endometrial cancer.