Co-expression of GPR30 and ERβ and their association with disease progression in uterine carcinosarcoma

OBJECTIVE: We sought to evaluate the expression of G protein-coupled receptor 30 (GPR30) and estrogen receptor (ER)beta in uterine carcinosarcoma (CS). STUDY DESIGN: Immunohistochemistry was performed using antibodies to GPR30, ER beta, ER alpha, and progesterone receptor (PR). The staining intensity and percentage of positive cells were scored for each tissue section. Expression levels were compared using the Wilcoxon rank sum test. Correlation was evaluated by Spearman rho and logistic regression. RESULTS: Compared with normal endometrium, CS had lower ER alpha and PR expression (both P < .01) but higher GPR30 epithelial expression (P = .03). Advanced-stage CS had higher GPR30 (P < .01) and ER beta (P = .02) epithelial expression compared with early-stage CS. Expression of GPR30 and ER beta correlated with each other (P < .01), and not with ER alpha or PR. CONCLUSION: In uterine CS, GPR30 and ER beta are coordinately overexpressed and expression levels increase in advanced-stage disease, supporting the involvement of alternative ERs in disease progression.