OBJECTIVE: To investigate the role of estrogen receptor-related receptor (ERR), a subfamily of orphan receptors, in the tumorigenesis of endometrial carcinoma and to evaluate the clinical significance. METHODS: A total of 46 cases of endometrial carcinoma tissues and 24 cases of normal endometrium tissues were collected. Semi-quantitative reverse transcription polymerase chain reaction and immunohistochemistry were used to measure the expressions of ERR. All samples were classified into two groups according to ERalpha status. RESULTS: It was positively correlated between the ERR (alpha, beta, gamma) mRNA and protein expression (r = 0.462, P = 0.009; r = 0.689, P = 0.016 and r = 0.673, P = 0.001). The expression rate and level of ERRalpha mRNA in ERalpha-positive endometrial carcinoma (42%, 0.24 +/- 0.18) were lower than in normal endometrium (78%, 0.42 +/- 0.23; P = 0.019, P = 0.021). No significant difference was observed in the expression of ERRbeta mRNA between endometrial carcinoma (23%, 0.21 +/- 0.16) and normal endometrium (22%, 0.27 +/- 0.15; P > 0.05). In ERalpha-positive endometrial carcinoma, the expression level of ERRgamma mRNA (0.93 +/- 0.24) was higher than normal endometrium (0.72 +/- 0.21; P = 0.023). The numbers of patients of Federal International Gynecological Oncology (FIGO) stage II-IV and of deep myometrial invasion in ERRalpha mRNA positive endometrial carcinoma group were more than those in ERRalpha mRNA negative group (P = 0.017 and P = 0.033). ERRgamma mRNA positive patients had a lower occurrence of lymph metastases than negative patients (P = 0.021). CONCLUSIONS: ERR may be closely related with the tumorigenesis of endometrial carcinoma, similar to ER. ERRalpha may serve as a biomarker of poor prognosis and ERRgamma as a favorable biomarker in endometrial carcinoma.
OBJECTIVE: To investigate the role of estrogen receptor-related receptor (ERR), a subfamily of orphan receptors, in the tumorigenesis of endometrial carcinoma and to evaluate the clinical significance. METHODS: A total of 46 cases of endometrial carcinoma tissues and 24 cases of normal endometrium tissues were collected. Semi-quantitative reverse transcription polymerase chain reaction and immunohistochemistry were used to measure the expressions of ERR. All samples were classified into two groups according to ERalpha status. RESULTS: It was positively correlated between the ERR (alpha, beta, gamma) mRNA and protein expression (r = 0.462, P = 0.009; r = 0.689, P = 0.016 and r = 0.673, P = 0.001). The expression rate and level of ERRalpha mRNA in ERalpha-positive endometrial carcinoma (42%, 0.24 +/- 0.18) were lower than in normal endometrium (78%, 0.42 +/- 0.23; P = 0.019, P = 0.021). No significant difference was observed in the expression of ERRbeta mRNA between endometrial carcinoma (23%, 0.21 +/- 0.16) and normal endometrium (22%, 0.27 +/- 0.15; P > 0.05). In ERalpha-positive endometrial carcinoma, the expression level of ERRgamma mRNA (0.93 +/- 0.24) was higher than normal endometrium (0.72 +/- 0.21; P = 0.023). The numbers of patients of Federal International Gynecological Oncology (FIGO) stage II-IV and of deep myometrial invasion in ERRalpha mRNA positive endometrial carcinoma group were more than those in ERRalpha mRNA negative group (P = 0.017 and P = 0.033). ERRgamma mRNA positive patients had a lower occurrence of lymph metastases than negative patients (P = 0.021). CONCLUSIONS:ERR may be closely related with the tumorigenesis of endometrial carcinoma, similar to ER. ERRalpha may serve as a biomarker of poor prognosis and ERRgamma as a favorable biomarker in endometrial carcinoma.