Genomic and epigenomic heterogeneity in molecular subtypes of gastric cancer

Abstract

Gastric cancer is a complex disease that is affected by multiple genetic and environmental factors. For the precise diagnosis and effective treatment of gastric cancer, the heterogeneity of the disease must be simplified; one way to achieve this is by dividing the disease into subgroups. Toward this effort, recent advances in high-throughput sequencing technology have revealed four molecular subtypes of gastric cancer, which are classified as Epstein-Barr virus-positive, microsatellite instability, genomically stable, and chromosomal instability subtypes. We anticipate that this molecular subtyping will help to extend our knowledge for basic research purposes and will be valuable for clinical use. Here, we review the genomic and epigenomic heterogeneity of the four molecular subtypes of gastric cancer. We also describe a mutational meta-analysis and a reanalysis of DNA methylation that were performed using previously reported gastric cancer datasets.

Keywords: DNA methylation; Gastric cancer; Molecular subtype; Mutation; Next-generation sequencing

Core tip: For the effective diagnosis and treatment of gastric cancer, a recent sequencing study classified gastric cancer into four molecular subtypes, which include Epstein-Barr virus-positive, microsatellite instability, genomically stable, and chromosomal instability subtypes. This molecular subtyping will extend our knowledge for basic research and will be valuable for clinical uses. We herein discuss the genomic and epigenomic heterogeneity of the four molecular subtypes of gastric cancer. We also describe a meta-analysis result that was performed using previously reported sequencing datasets.