BRCA1-associated protein 1 expression and prognostic role in prostate adenocarcinoma

Purpose: As prostate cancer (PCa) is the second most commonly diagnosed cancer worldwide, finding novel markers for prognosis is crucial.BRCA1-associated protein 1 (BAP-1), a nuclear-localized deubiquitinating enzyme, has been reported in several human cancers.However, its prognostic role in PCa remains unknown.Herein, we assessed the prognostic and clinicopathologic significance of BAP-1 in PCa.Materials and Methods: Seventy surgical specimens from radical prostatectomy cases were examined.Two cores per case were selected for construction of tissue microarrays (TMAs).After the exclusion of two cases because of tissue sparsity, BAP-1 immunohistochemical expression was evaluated in 68 cases of formalin-fixed, paraffin-embedded TMA tissue blocks.The immunohistochemical stain was scored according to proportion of nuclear staining: negative (<10% of tumor cells) or positive (≥10% of tumor cells).Results: BAP-1 expression was negative in 30 cases (44.1%) and positive in 38 cases (55.9%).Positive BAP-1 expression was more common in pT3b disease than in pT2 (p=0.038).A high preoperative prostate-specific antigen level was correlated with BAP-1 expression (p=0.014).Age, lymphovascular invasion, perineural invasion, and grade group were not significantly correlated with BAP-1 expression.Patients with positive BAP-1 expression showed significantly shorter disease-free survival (p=0.013).Additionally, BAP-1 was an independent prognostic factor of PCa (p=0.035;hazard ratio, 9.277; 95% confidence interval, 1.165-73.892).Conclusions: Our study findings showed an association of BAP-1 expression with poor PCa prognosis and suggest a potential role for BAP-1 as a prognostic biomarker for PCa.