Prognostic value of stromal and epithelial periostin expression in human prostate cancer: correlation with clinical pathological features and the risk of biochemical relapse or death

• Main Authors: Nuzzo Pier Vitale, Rubagotti Alessandra, Zinoli Linda, Ricci Francesco, Salvi Sandra, Boccardo Simona, Boccardo Francesco
• Format: Article
• Language: English
• Published: BMC 2012-12-01
• Series: BMC Cancer
• Subjects: POSTN protein; Human; Prostatic neoplasms; Extracellular matrix proteins; Prognosis; Biomarkers
• Online Access: http://www.biomedcentral.com/1471-2407/12/625

<p>Abstract</p> <p>Background</p> <p>The purpose of the present study was to evaluate the prognostic value of POSTN expression following prostatectomy.</p> <p>Methods</p> <p>Periostin (POSTN) expression in prostate cancer (PCa) and in normal specimens was evaluated in 90 patients by an immuno-reactive score(IRS) based on the intensity of immunostaining and on the quantity of stained cells. The t-test was applied to compare IRS values in cancer specimens to values in normal specimens. Pearson’s test was used to correlate POSTN expression to clinical pathologic features. PSA progression-free and survival curves were constructed by the Kaplan–Meier method and compared using the log-rank test. Multi-parametric models were constructed according to the Cox technique adding all the covariates predicting for either PSA progression or death into the models after univariate analysis.</p> <p>Results</p> <p>Both stromal and epithelial POSTN expression were significantly increased in tumor tissues<b>.</b> In particular, we found stromal expression to be significantly higher than epithelial expression as compared to normal tissues (p<0.000 and p=0.001).A significant correlation between POSTN epithelial expression and extra-prostatic extension was found (p=0.03). While high stromal expression was significantly associated with shorter survival (p=0.008), a low epithelial score significantly correlated with shorter PSA-free survival (p=0.04), suggesting that POSTN plays an apparently opposing biological role depending on its compartmentalization.Regardless of the mechanism that is involved, patients showing both high stromal and low epithelial expression made up a subgroup with a very bleak prognosis.</p> <p>Conclusions</p> <p>Although requiring further validation through larger studies, our findings show that POSTN might represent a novel prognostic marker for PCa.</p>