The complex signaling network across stromal, epithelial and immune cells demonstrates activated or suppressed key oncogenic/tumor suppressive pathways in GC such as epithelial‐mesenchymal (EMT), gastrointestinal mucosal barrier and cytotoxic CD8+ T‐cell/Natural Killer (NK) cell activation (Fig. 5a, Table 1). The gene discussed is CD8A; the disease is neoplasm.