Epigenetic Age Acceleration of Stomach Adenocarcinoma Associated With Tumor Stemness Features, Immunoactivation, and Favorable Prognosis.

Jinyao Chen,Hong Yu,Jianfeng Li,Hong Chen,Shiqiang Zhang,Shaohua Yang,Qiaojin Wang,Danhui Zhong,Wenhui Wu,Liang Li,Changhua Zhang,Mingzhe Li,Chunhong Hong,Qianlin Zeng

doi:10.3389/fgene.2021.563051

Abstract

Background: Abnormal DNA methylation (DNAm) age has been assumed to be an indicator for canceration and all-cause mortality. However, associations between DNAm age and molecular features of stomach adenocarcinoma (STAD), and its prognosis have not been systematically studied.Method: We calculated the DNAm age of 591 STAD samples and 115 normal stomach samples from The Cancer Genome Atlas (TCGA) and gene expression omnibus (GEO) database using the Horvath’s clock model. Meanwhile, we utilized survival analysis to evaluate the prognostic value of DNAm age and epigenetic age acceleration shift. In addition, we performed weighted gene co-expression network analysis (WGCNA) to identify DNAm age-associated gene modules and pathways. Finally, the association between DNAm age and molecular features was performed by correlation analysis.Results: DNA methylation age was significantly correlated with chronological age in normal gastric tissues (r = 0.85, p < 0.0001), but it was not associated with chronological age in STAD samples (r = 0.060, p = 0.2369). Compared with tumor adjacent normal tissue, the DNAm age of STAD tissues was significantly decreased. Meanwhile, chronological age in STAD samples was higher than its DNAm age. Both DNAm age and epigenetic acceleration shift were associated with the prognosis of STAD patients. By using correlation analysis, we also found that DNAm age was associated with immunoactivation and stemness in STAD samples.Conclusion: In summary, epigenetic age acceleration of STAD was associated with tumor stemness, immunoactivation, and favorable prognosis.

Highlights

Gastric cancer (GC) is one of the most common gastrointestinal tract malignancy and it is the leading causes of cancerrelated mortality worldwide (Van Cutsem et al, 2016; Siegel et al, 2018; Sitarz et al, 2018)
DNA methylation age was significantly correlated with chronological age in normal gastric tissues (r = 0.85, p < 0.0001), but it was not associated with chronological age in Stomach adenocarcinoma (STAD) samples (r = 0.060, p = 0.2369)
We found that DNA methylation (DNAm) age was associated with immunoactivation and stemness in STAD samples

Summary

Introduction

Gastric cancer (GC) is one of the most common gastrointestinal tract malignancy and it is the leading causes of cancerrelated mortality worldwide (Van Cutsem et al, 2016; Siegel et al, 2018; Sitarz et al, 2018). DNAm age for each breast cancer patients in Ren et al.’s paper was calculated based on cancer tissue samples; (ii) the outcome indicators of the two studies were different. The outcome indicators of Ren et al.’s study were the prognosis and recurrence of breast cancer patients; and (iii) the variables included in the two studies are different, which may have an impact on the model. Taken together, these studies indicated a new perspective on the pathogenesis and prognostic biomarker of cancer. Associations between DNAm age and molecular features of stomach adenocarcinoma (STAD), and its prognosis have not been systematically studied

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Results

Discussion

Conclusion