Published online Jul 15, 2022. doi: 10.4251/wjgo.v14.i7.1295
Peer-review started: January 11, 2022
First decision: March 13, 2022
Revised: March 18, 2022
Accepted: May 28, 2022
Article in press: May 28, 2022
Published online: July 15, 2022
Most gastric cancer (GC) patients are diagnosed at middle or late stage because the symptoms in early stage are obscure, which causes higher mortality rates of GC. Helicobacter pylori (H. pylori) was identified as a class I carcinogen and leads to aberrant DNA methylation/hydroxymethylation. 5-hydroxymethylcytosine (5-hmC) plays complex roles in gene regulation of tumorigenesis and can be considered as an activating epigenetic mark of hydroxymethylation.
To explore the association between 5-hmC levels and the progression and prognosis of GC patients with or without H. pylori infection.
A retrospective cohort study was conducted to estimate the predicted value of 5-hmC level in the progression and prognosis of GC patients with different H. pylori infection status. A total of 144 GC patients were recruited.
The levels of 5-hmC were significantly decreased in tumor tissues (0.076 ± 0.048) compared with the matched control tissues (0.110 ± 0.057, P = 0.001). A high level of 5-hmC was an independent significant favorable predictor of overall survival in GC patients (hazard ratio = 0.61, 95% confidence interval: 0.38-0.98, P = 0.040), the H. pylori-negative GC subgroup (hazard ratio = 0.30, 95% confidence interval: 0.13-0.68, P = 0.004) and the GC patients with TNM stage Ⅰ or Ⅱ (hazard ratio = 0.32, 95% confidence interval: 0.13-0.77, P = 0.011).
Increased 5-hmC is a favorable prognostic factor in GC, especially for H. pylori-negative subgroups.
Core Tip: Helicobacter pylori (H. pylori) was identified as a class I carcinogen and leads to aberrant DNA methylation/hydroxymethylation. 5-hydroxymethylcytosine plays complex roles in the gene regulation of tumorigenesis and is considered an activating epigenetic mark of hydroxymethylation. We conducted a retrospective cohort study to estimate the predictive value of 5-hydroxymethylcytosine levels in the progression and prognosis of gastric cancer patients with different H. pylori infection statuses. The results indicated that increasing 5-hydroxymethylcytosine is a favorable prognostic factor in gastric cancer patients who were not infected with H. pylori, but no associations were observed in H. pylori-positive gastric cancer patients.