Distinct esophageal adenocarcinoma molecular subtype has subtype-specific gene expression and mutation patterns

Area of Science:

• Oncology
• Molecular Biology
• Genomics

Background:

• Esophageal carcinoma (EC) comprises esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC).
• EAC prevalence has increased significantly in Western countries over the past 30 years, yet treatment options remain limited.
• Molecular subtyping holds promise for targeted therapies, but EAC subtypes are not yet defined.

Purpose of the Study:

• To identify and define molecular subtypes of esophageal adenocarcinoma (EAC).
• To provide insights for the development of novel targeted therapies for EAC.

Main Methods:

• Meta-analysis of gene expression profiling data from three independent EAC cohorts.
• Analysis of subtype-specific gene expression patterns and mutation signatures.

Main Results:

• Two common molecular subtypes of EAC were identified, each with distinct expression patterns and mutation profiles.
• Subtype I EACs showed enrichment in epithelial and keratinocyte differentiation pathways.
• TP53 and CDKN2A mutations were common to both subtypes, with subtype-specific mutations including SMAD4 in subtype I and ARID1A in subtype II.

Conclusions:

• Two distinct and validated molecular subtypes of EAC have been defined.
• These findings may pave the way for new, targeted therapeutic strategies for esophageal adenocarcinoma.