A study of the diagnostic and prognostic role of enhancer of zeste homolog 2 and BRCA1-associated protein 1 expression in different prostatic lesions (an immunohistochemical study)

Abstract

Aim To ascertain the applicability of enhancer of zeste homolog 2 (EZH2) and breast cancer gene 1 (BRCA1)-associated protein 1 (BAP-1) in the diagnosis of prostatic adenocarcinoma (PCa) as well as their correlation with different clinicopathological characteristics of PCa cases and the patients’ disease-free survival. Patient and methods This study included 10 cases of benign prostatic hyperplasia (BPH), 6 cases of high-grade prostatic intraepithelial neoplasm PIN (HGPIN), and 60 cases of PCa. Immunohistochemical staining techniques were used to evaluate the roles of EZH-2 and BAP-1 in PCa and their correlations to different clinicopathological data and patient survival. Results High nuclear positivity of EZH2 was detected in 53.3% of PCa, while 80% of BPH and 66.7% of HGPIN cases showed no/low expression. Conversely, BAP1 nuclear positivity was detected in 70% of BPH and 50% of HGPIN versus 48.3% of PCa cases. Using the receiver-operating characteristic curve, the EZH2 showed 60.2% sensitivity, 83.3% specificity, and 65% diagnostic accuracy compared with BAP1 that showed 86.7, 51.7, and 58.7%, respectively. However, the markers showed 70% sensitivity, 56.2% specificity, and 67.1% diagnostic accuracy when tested synchronously. A statistically significant inverse relationship between EZH 2 and BAP1 nuclear expression in the examined PCa cases was found. Furthermore, EZH-2 overexpression and BAP-1 nuclear loss are associated with unfavorable clinicopathological characteristics. Moreover, it was demonstrated that EZH-2 overexpression and low patient survival were statistically correlated. Conclusions These results suggest that both EZH2 and BAP1 can be added to the diagnostic panel of PCa and can serve as potential independent prognostic biomarkers for predicting the outcome of patients.