The Effects of Protocadherin 8 and WWOX in Prostate Adenocarcinoma

Abstract

Objective: The protocadherin 8 (PCDH8) gene, located on chromosome 13q14.3 encodes an integral membrane protein. WWOX (fragile site FRA16D oxido-reductase) is a tumor suppressor gene located in region 16q23.324.1. The aim of this study was to investigate the staining pattern of protocadherin 8 and WWOX in adenomatous hyperplasia and prostate adenocarcinoma. Methods: Seventy adenomatous hyperplasia and 70 prostate adenocarcinoma preparations stored at the pathology department from 2013-2016 were retrospectively analyzed. Samples immunohistochemically stained with WWOX or protocadherin 8 were evaluated by two pathologists under a light microscope. After pathological investigation of the samples, the expression of WWOX and protocadherin 8 was scored. WWOX and PCD118 expression was assessed semi-quantitatively according to staining intensity scored as none, mild, moderate, and strong (0 to 3+). For analysis of the data, the mild, moderate and strong staining scores were combined (as positive) and the data were classified as negative or positive. Differences in the WWOX or protocadherin 8 staining results between adenomatous hyperplasia and prostate adenocarcinoma cases were examined using a two-way chi-square test and binary logistic regression analysis. Result: Statistical analysis showed that WWOX expression was higher in adenomatous hyperplasia than in prostate adenocarcinomas. This difference was statistically significant (p = 0.035). There was no difference in PCDH8 expression between adenomatous hyperplasia and prostate adenocarcinoma samples (p= 0.217). Conclusion: In this study, the expression of WWOX decreased and the expression of PCDH8 remained unchanged in PCa cases. In terms of prognostic significance, it can be concluded that WWOX is a good prognostic parameter, while PCDH8 was an ineffective prognostic marker. In addition, the investigation of protocadherin 8 in larger series may provide more meaningful results.