CIP2A expression is increased in prostate cancer

Expression of the CIP2A protein was studied using immunohistochemistry in prostate cancer (n = 59) and in benign prostatic hyperplasia (n = 20) specimens. The CIP2A staining scores were compared with several clinicopathological parameters.Expression of CIP2A was increased in prostate cancer epithelium as compared with the benign hyperplastic epithelium (p < 0.001). The expression of CIP2A was associated with high Gleason scores (p < 0.001) and among patients treated with radical prostatectomy, CIP2A expression was associated with pre-treatment risk stratification (p = 0.011) and pathological T-class (p = 0.031). No statistically significant association was detected between CIP2A expression and prostate specific antigen concentrations.Expression of the CIP2A protein is increased in prostate cancer specimens and its expression is associated with poorly differentiated and high-risk tumors.Serine/threonine protein phosphatase 2A (PP2A) is a tumor suppressor that plays an integral role in the regulation of a number of major signaling pathways which can contribute to carcinogenesis [1]. The cellular inhibitor of PP2A, named CIP2A (and also known as KIAA1524 and p90 tumor-associated antigen), is a recently identified human oncoprotein which promotes MYC protein stability by inhibiting PP2A-mediated dephosphorylation of MYC [2]. An increased expression of CIP2A has been detected in gastric [3,4], breast [5] and colon adenocarcinomas and in head and neck squamous cell carcinomas [2]. Interestingly, auto-antibodies against CIP2A were detected in over 30% of sera from prostate adenocarcinoma patients while only 1.5% of benign prostatic hyperplasia (BPH) patients were found to be positive for these antibodies [6].The aim of this study was to investigate expression of the CIP2A protein in prostate cancer specimens and in BPH samples, and to examine whether CIP2A immunopositivity is associated with clinicopathological parameters in these patients.Archived prostate specimens were