[Expression of estrogen receptor-related receptor isoforms in endometrial carcinoma tissues and its clinical significance].
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.
Gao
Min
M
Department of Gynecology, Peking University People's Hospital, Beijing 100044, China.
Wei
Li-hui
LH
Sun
Peng-ming
PM
Zhao
Dan
D
Wang
Jian-liu
JL
Wang
Zhi-qi
ZQ
Zhao
Chao
C
D000328:Adult; D000368:Aged; D016889:Endometrial Neoplasms / Q000378:metabolism* / Q000473:pathology; D047628:Estrogen Receptor alpha / Q000096:biosynthesis*; D047629:Estrogen Receptor beta / Q000096:biosynthesis*; D005260:Female; D006801:Humans; D008875:Middle Aged; D011379:Prognosis; D020033:Protein Isoforms / Q000096:biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction
D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D020033:Protein Isoforms; D012333:RNA, Messenger