Cpg Islands Hypermethylatioin the Promoter Region of Gstp1 Gene in Cell-Free Dna As a Noninvasive Biomarker for Detecting Prostate Cancer



Jamshidian F¹ ; Akbari MT^{2, 3} ; Noormohammadi Z¹ ; Nourozi MR⁴ ; Pourmand GR⁵
Source: Biochemical and Cellular Archives Published:2016

Abstract

Noninvasive and accurate approaches for the early detection and management of prostate cancer are needed. Genetic alterations have been used as targets for the detection of neoplastic cells in bodily fluids from many cancer types. Hypermethylation of regulatory sequences in GSTP1 gene occurs in more than 90% of cases of prostate cancer, but not in normal prostatic tissue or other normal tissues. We evaluated circulating cell-free DNA GSTP1 CpG island hypermethylation as a prognostic biomarker in the plasma of men with prostate cancer. Prostate cancer DNA GSTP1 CpG island hypermethylation was detected using a restriction endonuclease quantitative PCR technique. We analyzed plasma samples in totally 150 samples, 50 men with clinically localized prostate cancer, 50 metastatic patient and 50 men with a negative prostate biopsy. 34 of 50 (68%) patient with localized prostate cancer and 42 of 50 (84%) metastatic patients (totally 76% patients with prostate cancer) were positive for GSTP1 methylation. 4 of 50 cases with negative prostate biopsy had very weak fluctuations at the target region. We successfully identified prostate cancer gene hypermethylation in the cell free DNA in prostate cancer patients with this protocol. This method can effectively distinguish BPH from prostate neoplasm. Our suggestion is that, using Cell free DNA is an ideal non-invasive technique to detect prostate cancer.