Field Cancerization in Sporadic Colon Cancer

• Published in: Gut and liver 2016-09, Vol.10 (5), p.773
• Main Authors: Soo-kyung Park, Chang Seok Song, Hyo-joon Yang, Yoon Suk Jung, Kyu Yong Choi, Dong Hoe Koo, Kyung Eun Kim, Kyung Uk Jeong, Hyung Ook Kim, Hungdai Kim, Ho-kyung Chun, Dong Il Park
• Format: Article
• Language: Korean
• Subjects: Colorectal neoplasms; DNA methylation; Epigenomics; Field effect
• ISSN: 1976-2283

Background/Aims: Aberrant DNA methylation has a specific role in field cancerization. Certain molecular markers, including secreted frizzled-related protein 2 (SFRP2), tissue factor pathway inhibitor 2 (TFPI2), N-Myc downstream-regulated gene 4 (NDRG4) and bone morphogenic protein 3 (BMP3), have previously been shown to be hypermethylated in colorectal cancer (CRC). We aim to examine field cancerization in CRC based on the presence of aberrant DNA methylation in normal-appearing tissue from CRC patients. Methods: We investigated promoter methylation in 34 CRC patients and five individuals with normal colonoscopy results. CRC patients were divided into three tissue groups: tumor tissue, adjacent and nonadjacent normal-appearing tissue. The methylation status (positive: methylation level >20%) of SFRP2, TFPI2, NDRG4, and BMP3 promoters was investigated using methylation-specific PCR. Results: The methylation frequencies of the SFRP2, TFPI2, NDRG4 and BMP3 promoters in tumor/adjacent/nonadjacent normal-appearing tissue were 79.4%/63.0%/70.4%, 82.4%/53.6%/60.7%, 76.5%/61.5%/69.2%, 41.2%/35.7%/50.0%, respectively. The methylation levels of the SFRP, TFPI2, NDRG4 and BMP3 promoters in tumor tissues were significantly higher than those in normal-appearing tissue (SFRP2, p=0.013; TFPI2, p