Abstract

Colorectal cancer (CRC) is one of the main causes of death in the world. Diagnosis in precancerous lesions stage is an important factor in reducing the mortality rate in CRC. Our study aimed at determining methylation status of secreted frizzled-related protein2 (SFRP2) gene in stool and serum samples of patients compared to healthy individuals. We collected serum and stool samples from 50 individuals including 25 patients with colorectal cancer and 25 healthy individuals. DNA was isolated from the serum and stool and treated by sodium bisulfite. It was then analyzed by methylation-specific polymerase chain reaction (MSP). Results showed that methylated SFRP2 occurs with significant different in patients with colorectal cancer compared to healthy individuals. Our result indicated that methylated SFRP2 occurs in 68 (17/25) and 48 (12/25) of stool DNA and cell-free DNA of patients with colorectal cancer, respectively. Methylated SFRP2 was detected in 8 (2/25) and 4 (1/25) of stool DNA and cfDNA of healthy individuals. Our result indicated that methylated SFRP2 occurred more frequently in stool DNA than cell-free DNA sample of patients with colorectal cancer. Methylated SFRP2 can be used as a potential noninvasive biomarker for screening high-risk individuals. In order to determine high sensitivity and specificity of this marker, more samples of Iranian individuals should be studied. © 2017, Springer-Verlag London Ltd.