DNMT3B Expression Might Contribute to Abnormal Methylation of RASSF1A in Lager Colorectal Adenomatous Polyps

Xianmei Meng; Na Liu; Yanbin Jia; Kerui Gong; Jingjie Zhang; Wei Zhang; Guo Shao; Tong Dang

doi:10.1155/2020/1798729

DNMT3B Expression Might Contribute to Abnormal Methylation of RASSF1A in Lager Colorectal Adenomatous Polyps

Gastroenterol Res Pract. 2020 Oct 1:2020:1798729. doi: 10.1155/2020/1798729. eCollection 2020.

Authors

Xianmei Meng^{1

2}, Na Liu³, Yanbin Jia^{1

3}, Kerui Gong⁴, Jingjie Zhang^{1

2}, Wei Zhang^{1

2}, Guo Shao³, Tong Dang^{1

2}

Affiliations

¹ Department of Gastroenterology, The Second Affiliated Hospital of Baotou Medical College, Baotou, 014030 Inner Mongolia Autonomous Region, China.
² Institute of Digestive Diseases of Inner Mongolia Autonomous Region, Baotou, 014030 Inner Mongolia Autonomous Region, China.
³ Inner Mongolia Key laboratory of Hypoxic Translational Medicine, Baotou Medical College, Baotou, 104060 Inner Mongolia Autonomous Region, China.
⁴ Department of Oral and Maxillofacial Surgery, University of California San Francisco, San Francisco, 94122 CA, USA.

Abstract

Background: It is pretty well known that DNA methyltransferases (DNMTs) are actively involved in abnormal cell growth. The goal of the current study is to explore the correlation between DNMT expression and colorectal adenomatous polyps (CAPs).

Method: Twenty pairs of CAP samples with a diameter ≥ 10 mm and corresponding normal colorectal mucosa (NCM) tissues from patients were used in the present study. The expression levels and activity of DNA methyltransferases (DNMTs) were measured in the CAP tissues. The global methylation and the promoter methylation level of 3 kinds of tumour suppressor gene were detected.

Results: mRNA and protein levels of DNMT3B were found to be elevated in the CAP tissues compared with the control tissue. Additionally, the methylation of long interspersed nuclear elements-1 (LINE-1/L1) was decreased in the CAP tissue. Furthermore, methylation of the promoter of a tumour suppressor gene Ras association domain family 1A (RASSF1A) was increased in the CAP tissues, while the mRNA levels of RASSF1A were decreased.

Conclusions: These results suggest that the overexpression of DNMT3B may contribute to a role in the genesis of CAPs through the hypomethylation of chromosomes in the whole cell and promoter hypermethylation of RASSF1A.