Increased expression of estrogen-related receptor alpha (ERRalpha) is a negative prognostic predictor in human prostate cancer.
The nuclear receptor ERRalpha (estrogen-related receptor alpha) is known to modulate the estrogen-signaling pathway, but the biological significance of ERRalpha in the prostate remains unclear. We investigated the expression of ERRalpha in human prostate tissues and cancer cell lines to evaluate the potential roles of the receptor in prostate cancer (PC). Western blot analysis of ERRalpha was performed in three cell lines of human PC (LNCaP, DU145 and PC-3). The expressions of ERRalpha in cancerous lesions (n = 106) and benign foci (n = 99) of 106 surgically obtained prostate specimens were evaluated by immunohistochemistry. The relationships between the ERRalpha expression and clinicopathological features were evaluated. Western blot analysis using the polyclonal anti-ERRalpha antibody detected a 52 kD band in all three PC cell lines. Positive immunostaining of ERRalpha in the nuclei was found in 73 (69%) cancerous and 47 (47.5%) benign epithelium, whereas the stromal tissues were negative for ERRalpha. The mean immunoreactivity score (IR score) of the cancerous lesions (3.5 +/- 2.6) was significantly higher than that of the benign foci (1.8 +/- 2.1) (p < 0.0001). The IR score of the cancerous lesions significantly correlated with the Gleason score (p = 0.0135). Univariate and multivariate hazard analyses revealed significant correlations between elevated ERRalpha expression and poor cancer-specific survival (p = 0.0141 and 0.0367, respectively). The enhanced expression of ERRalpha might play a role in the development of human PC and serve as a significant prognostic factor for the disease.
Fujimura
Tetsuya
T
Department of Urology, Faculty of Medicine, The University of Tokyo, Tokyo, Japan.
Takahashi
Satoru
S
Urano
Tomohiko
T
Kumagai
Jinpei
J
Ogushi
Tetsuo
T
Horie-Inoue
Kuniko
K
Ouchi
Yasuyoshi
Y
Kitamura
Tadaichi
T
Muramatsu
Masami
M
Inoue
Satoshi
S
D000368:Aged; D045744:Cell Line, Tumor; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology; D011960:Receptors, Estrogen / Q000378:metabolism*; D000097983:ERRalpha Estrogen-Related Receptor
D011960:Receptors, Estrogen; D000097983:ERRalpha Estrogen-Related Receptor