ESRRA and Familial prostate cancer: In order to elucidate further its clinical significance in the advanced progression of prostate cancer, we performed immunohistochemistry of ERRα in a prostatic tissue microarray slide containing benign prostatic hyperplasia (BPH, n = 3), and prostate cancer (n = 93) tissues of different Gleason scores (GS), and results showed that few cells showing positively-stained nuclei were detected in BPH and low-grade prostate cancer lesions, whereas significant increase of malignant cells with intense nuclear immunoreactivity was noticed in high-grade prostate cancer lesions.