Gas Protein Expression Is an Independent Predictor of Recurrence in Prostate Cancer

摘要

Background. T393C polymorphism in the gene GNAS1, which encodes the G-protein alpha s subunit (Gas) of heterotrimeric G protein, is significantly associated with the clinical outcome of patients suffering from several cancers. However, studies on the role and protein expression of Gas subunit in prostate cancer were still unavailable. Methods. The immunohistochemical staining was used to assess Gas expression through tissue microarray procedure of 56 metastatic PCas, 291 localized PCas, and 67 benign hyperplasia (BPH). Gas expression was semiquantitatively scored and evaluated the correlation with pathologic parameters and biochemical recurrence of prostate-specific antigen (PSA). Results. Gas expression was localized in nuclear and cytoplasm in prostate cancer cells and downregulated in metastatic PCa compared to localized PCa and BPH (P < 0.001). Gas was inversely associated with PSA level and Gleason scores; patients with low expression of Gas had adverse dincopathological features. In multivariable Cox regression analysis, high Gas expression and Gleason scores were independent predictors of both PSA progression-free and overall survival. Conclusions. Gas down-expression is associated with adverse pathologic features and clinical PSA biochemical recurrence of prostate cancer. Gas is an independent predictor to help determine the risk of PSA progression and death.