Objective: Some studies have shown that the methylation status of the GSTP1 gene promoter is related to the incidence of prostate cancer, but this finding is still controversial. The aim of this study was to evaluate the association between glutathione-S-transferase p1 (GSTP1) promoter methylation and the incidence of prostate cancer.
Methods: The Medline, Embase, Web of Science, and Cochrane CENTRAL databases were searched from their inception to February 22, 2019. According to the inclusion criteria, studies of the association between the methylation status of the GSTP1 gene promoter and prostate cancer were included. The difference in the incidence of GSTP1 promoter methylation in tissues, blood, or urine between patients with prostate cancer and those without prostate cancer were compared, and the results were expressed as the odds ratio (OR) and 95% confidence interval (CI). The pooled OR of each study was estimated using a fixed-effects model or a random-effects model to generate forest plots.
Results: Ultimately, 15 studies (1540 samples) were included. The estimated effect from our meta-analysis showed that the incidence of GSTP1 promoter methylation was higher in patients with prostate cancer than in those without prostate cancer (OR 18.58, 95% CI 9.60-35.95, P = 0.000). GSTP1 promoter methylation was highly correlated with the incidence of prostate cancer.
Conclusions: Methylation of the GSTP1 promoter may increase the risk of prostate cancer. This study may provide a strategic direction for prostate cancer research. Pending validation of these findings, the methylation of the GSTP1 promoter may be a potential biomarker to diagnose prostate cancer.
Keywords: Glutathione-S-transferase p1; Meta-analysis; Methylation; Prostate cancer.