Dataset Information

Helicobacter pylori Eradication Can Reverse the Methylation-Associated Regulation of miR-200a/b in Gastric Carcinogenesis.

ABSTRACT:

Background/aims

Epigenetic change is one of the mechanisms that regulates the expression of microRNAs (miRNAs) and is known to play a role in Helicobacter pylori-associated gastric carcinogenesis. We aimed to evaluate the epigenetic changes of miR-200a/b in H. pylori-associated gastric carcinogenesis and restoration after eradication.

Methods

The expression and methylation levels of miR-200a/b were evaluated in gastric cancer (GC) cell lines, human gastric mucosa of H. pylori-negative and -positive controls, and H. pyloripositive GC patients. Next, the changes in the expression and methylation levels of miR-200a/b were compared between H. pylori -eradication and H. pylori -persistence groups at 6 months. Real-time reverse transcription-polymerase chain reaction was conducted to investigate the miRNA expression levels, and MethyLight was performed to assess the methylation levels.

Results

In the GC cell lines, the level of miR- 200a/b methylation decreased and the level of expression increased after demethylation. In the human gastric mucosa, the miR-200a/b methylation levels increased in the following group order: H. pylori-negative control group, H. pylori-positive control group, and H. pylori-positive GC group. Conversely, the miR-200a/b expression levels decreased in the same order. In the H. pylori -persistence group, no significant changes were observed in the methylation and expression levels of miR-200a/b after 6 months, whereas the level of methylation decreased and the level of expression of miR-200a/b increased significantly 6 months in the H. pylori-eradication group.

Conclusions

Epigenetic alterations of miR-200a/b may be implicated in H. pylori -induced gastric carcinogenesis. This field defect for cancerization is suggested to be improved by H. pylori eradication.

SUBMITTER: Choi JM

PROVIDER: S-EPMC7492500 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Publications

<i>Helicobacter pylori</i> Eradication Can Reverse the Methylation-Associated Regulation of <i>miR-200a/b</i> in Gastric Carcinogenesis.

Choi Ji Min JM Kim Sang Gyun SG Yang Hyo-Joon HJ Lim Joo Hyun JH Cho Nam-Yun NY Kim Woo Ho WH Kim Joo Sung JS Jung Hyun Chae HC

Gut and liver 20200901 5

<h4>Background/aims</h4>Epigenetic change is one of the mechanisms that regulates the expression of microRNAs (miRNAs) and is known to play a role in Helicobacter pylori-associated gastric carcinogenesis. We aimed to evaluate the epigenetic changes of <i>miR-200a/b</i> in <i>H. pylori</i>-associated gastric carcinogenesis and restoration after eradication.<h4>Methods</h4>The expression and methylation levels of <i>miR-200a/b</i> were evaluated in gastric cancer (GC) cell lines, human gastric muc ...[more]

PMID: 31887809

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