Pan-cadherin as a high level phenotypic biomarker for prostate cancer

Purpose: High level phenotypic biomarkers such as cadherins are needed to identify individuals at risk for biologically active prostate cancer and determine which individuals with elevated prostate specific antigen or a prostate nodule are candidates for re-biopsy. Cadherins are a high level phenotypic biomarker associated with decreased cell adhesion, which is a cardinal event in carcinogenesis. Recently we reported that G-actin and tissue transglutaminase type II are potential biomarkers for prostate cancer. In this study we present cadherins as a potential third component of the biomarker profile. Materials and Methods: Prostate tissues from 38 patients with cancer and 33 controls with a 10-year prostate cancer-free followup were labeled for pan-cadherin by immunohistochemical testing. Immunoreactivity was quantified using a Pathology Workstation (Autocyte Inc., Elon College, North Carolina). Results: Visually benign glands from controls generally expressed cadherins, whereas regions of adenocarcinoma were generally negative. On quantitative immunohistochemistry 36 of 38 prostate cancer cases expressed a lower mean percent area positive for cadherin than the 19 benign prostatic hyperplasia and 14 prostatitis cases (odds ratio 978, 95% confidence interval 45 to 21,140, relative risk 18, 95% confidence interval 5 to 67, p <0.0001). Receiver operating characteristics analysis of immunohistochemical testing data showed that an optimal threshold of 7 produced 95% sensitivity and 100% specificity. Conclusions: Quantitative down-regulation of cadherin expression in prostate cancer tissue sections is a strong biomarker for prostate cancer. Analysis of cadherin and other high level phenotypic biomarker expression in the premalignant field may provide additional diagnostic information to decide which patients need re-biopsy, more intensive monitoring or chemoprevention.