Detection of novel gene mutation causing chromosomal instability using whole exome sequencing in colorectal cancer

2016 Fiscal Year Final Research Report

• Project/Area Number: 25460956
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Gastroenterology
• Research Institution: Kanazawa University (2015-2016); Nagoya City University (2013-2014)
• Principal Investigator: Sawada Takeshi 金沢大学, 医薬保健学総合研究科, 特任准教授 (60345626)
• Research Collaborator: YAMANO Hiro-o 札幌医科大学, 医学部, 准教授 ; SUGAI Tamotsu 岩手医科大学, 医学部, 教授 ; NOJIMA Masanori 東京大学医科学研究所付属病院, 准教授
• Project Period (FY): 2013-04-01 – 2017-03-31
• Keywords: 大腸癌 / 鋸歯状病変 / 遺伝子メチル化

Outline of Final Research Achievements

Due to the shortage of expense and clinical samples, we had to change initial research plan. Instead, we assessed the DNA methylation of cancer-associated genes in a cohort of BRAF-mutant precancerous lesions. We then compared those results with the lesions’ clinicopathological features, especially colorectal subsites. The prevalence of lesions exhibiting frequent DNA methylation was lower in the sigmoid colon and rectum than in other bowel subsites. In addition, several cancer-associated genes showed higher methylation levels within lesions in the proximal to sigmoid colon than in the sigmoid colon and rectum. These results indicate that the methylation status of lesions with BRAF mutation is strongly associated with their location. By contrast, no difference in aberrant DNA methylation was observed in normal-appearing background colonic mucosa along the bowel subsites, which may indicate the absence of an epigenetic field defect.

Free Research Field

大腸癌