G-protein-coupled estrogen receptor GPR30 and tamoxifen resistance in breast cancer
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : Atanas Ignatov Tanja Ignatov Christine Weißenborn holm Eggemann Joachim Bischoff Andrzej Semczuk Albert Roessner Serban Dan Costa Thom
- چاپ و سال / کشور: 2011
Description
Recently, we have shown that the new G-protein- coupled estrogen receptor GPR30 plays an important role in the development of tamoxifen resistance in vitro. This study was undertaken to evaluate the correlation between GPR30 and tamoxifen resistance in breast cancer patients. GPR30 protein expression was evaluated by immunohistochemical analysis in 323 patients with primary operable breast cancer. The association between GPR30 expression and tamoxifen resistance was confirmed in a second cohort of 103 patients treated only with tamoxifen. Additionally, we evaluated GPR30 expression in 33 primary tumors and in recurrent tumors from the same patients. GPR30 expression was detected in 56.7% of the breast cancer specimens investigated and it correlated with overexpression of HER-2 (P = 0.021), EGFR (P = 0.024) and lymph node status (P = 0.047). In a first cohort, survival analysis showed that GPR30 was negatively correlated with relapse-free survival (RFS) only in patients treated with tamoxifen (tamoxifen with or without chemotherapy). GPR30 expression was associated with shorter RFS (HR = 1.768; 95% CI, 1.156–2.703; P = 0.009). In a subset of patients treated only with tamoxifen, multivariate analysis revealed that GPR30 expression is an independent unfavorable factor for RFS (HR = 4.440; 95% CI, 1.408–13.997; P = 0.011). In contrast, GPR30 tended to be a favorable factor regarding RFS in patients who did not receive tamoxifen. In 33 paired biopsies obtained before and after adjuvant therapy, GPR30 expression significantly increased only under tamoxifen treatment (P = 0.001). GPR30 expression in breast cancer independently predicts a poor RFS in patients treated with tamoxifen.
Breast Cancer Res Treat (2011) 128:457–466 DOI 10.1007/s10549-011-1584-1 Received: 10 April 2011 / Accepted: 9 May 2011 / Published online: 24 May 2011 Springer Science+Business Media, LLC. 2011 Abstract Recently, we have shown that the
