Supplementary file 1_Molecular profiling and prognostic significance of gastric cancer subtypes based on extracellular vesicle-related characteristics.docx

This study aims to explore whether endocytosis pathway-associated genes and immune checkpoint-related features were linked to GC subtypes and prognosis.</p>Methods<p>Public transcriptomic datasets from TCGA and GEO were analyzed. ssGSEA was applied to predefined endocytosis-related gene sets, and NMF was used to identify molecular subtypes. Survival, tumor microenvironment features, tumor mutation burden, microsatellite instability, and differentially expressed genes were evaluated.

A three-gene prognostic model was developed and assessed through retrospective internal and external validation across public cohorts for prognostic association only.</p>Results<p>Two endocytosis-related subtypes were identified. The Group 1 subtype showed higher pathway activity, more immunosuppressive microenvironmental features, higher expression of selected immune checkpoint-related markers, and poorer survival. The Group 2 subtype showed lower pathway activity and more favorable outcomes.