The Role of Estrogen Receptors in Proliferation of Non-Small Cell Lung Cancer

To explore the expression pattern of ERs in NSCLC tissues and assess their relationship with tumor histopathological variable. In our study, Ers expression was examined using Real-time PCR with specimens of 28 NSCLC patients. It was shown that both ERɑ and Erβ were over expression in NSCLC tissues, and also the Mrna concentration of both ERɑ and Erβ were significantly higher in primary tumor T2 stage than in T1 stage and higher in squamous carcinoma than in adenocarcinoma. However, the activation of ERɑ and Erβ were completely different. To further explore the role of Ers in development and progression of NSCLC, we used Ers selective siRNA or antagonist in vitro experiments. The results showed that Erβ but not ERɑ can mediate E2 induced cell growth, since siRNA targeting Erβ but not ERɑ gene can induce cell cycle arrest at G1 phase by down regulation of cyclinD1 expression, and also cell cycle regulators p21Waf1/Cip1 and p53 were involved in this signaling pathway.