Assessment of GSTP1 Gene Methylation in Early Detection of Prostate Cancer in Egyptian Patients

This study has shed some light on the role of Glutathione S-transferase Pi 1 gene (GSTP1) methylation among Egyptians with prostate cancer and its potential use through urinary sample analysis as a sensitive non-invasive molecular technique for early detection of prostate cancer. The study was conducted on fifty age-matched Egyptian males. Twenty three of them were undergone TRUS-guided biopsy of the prostate for suspected malignancy. The remaining were divided into 17 individuals with PSA level between 3-10ng/ml, and 10 healthy controls with PSA values less than 2ng/ml. DNA was extracted from urine samples, peripheral blood leukocytes, and paraffin- embedded tissue sections. Methylation specific PCR was done for detection of GSTP1 hypermethylation. According to biopsy results; 11 out of 23 patients proved to have prostatic carcinoma, and the other 12 patients were with benign prostatic hyperplasia (BPH). Positive GSTP1 methylation pattern was detected in 90.9% (10/11) of DNA collected from both tissue and urine samples of the patients with prostate cancer, 20% of patients with BPH showed positive GSTP1 methylation pattern. 64.7% (11/17) of subjects with serum PSA levels between 3.0-10.0ng/ml have shown positive GSTP1 methyla-tion pattern.GSTP1 methylation was detected in 40% (4/10) of control individuals. Our results indicated that GSTP1 methylation is reliable molecular biomarker for early detection of prostate cancer (90.9% sensitivity). The assay is non-invasive and sensitive technique to detect prostate cancer rather than BPH using urine samples.