Molecular Diagnostic of Prostate Cancer From Body Fluids Using Methylation-Specific PCR (MS-PCR) Method.

BACKGROUND: Worldwide prostate cancer (PCa) represents the 2nd leading cause of cancer related deaths among men. Currently, the screening for early detection of PCa is based on determination of serum prostate-specific antigen (PSA) levels. But this biomarker presents some disadvantages related to its specificity and sensitivity. In our study, we want to determine if methylation levels of the glutathione S-transferase P1 (GSTP1) gene could be used as a new biomarker for the early detection of PCa and to distinguish between malignant and benign pros-tatic lesions.

METHODS: To determine the methylation levels of the GSTP1 gene, 31 men with histopathological diagnosis of prostate adenocarcinoma and 34 men with the histopathological diagnosis of benign prostatic hyperplasia (BPH) as controls were included in the study group. The genomic DNA was extracted from urine samples. We analyzed the methylation levels of the GSTP1 gene by methylation-specific polymerase chain reaction (MS-PCR) method.

RESULTS: In prostate cancer patients 27 of 31 (87%) presented hypermethylated levels of the GSTP1 gene, whereas 4 of 34 (11.8%) BPH patients had hypermethylated levels of the GSTP1 gene. Further, in the case of these four patients a second biopsy was done, which confirmed the diagnosis of prostate adenocarcinoma. Using the receiver operating curve (ROC), we obtained a specificity of 87% and a sensitivity of 98% for the GSTP1 gene.

CONCLUSIONS: We can conclude that GSTP1 represents a new molecular biomarker which can aid in early detection of PCa and be used to discriminate between benign and malignant prostatic lesions from body fluids by noninvasive methods.