This study employs a proteomic approach to characterize early pathological stages of GC, including chronic gastritis (CG), intestinal metaplasia and low-grade dysplasia (MI-DBG), and advanced stages such as EGC and GC. Specifically, this research seeks to (i) identify stage-specific proteomic signatures by determining differentially expressed proteins (DEPs) across lesional and non-lesional tissues at different stages of the disease progression, (ii) explore molecular pathways by analyzing disrupted biological processes to understand their role in GC progression; (iii) characterize shared and distinct protein deregulation patterns between early and advanced stages; and (iv) develop a systems biology framework to map protein interactions and identify key molecular regulators driving GC progression. These insights may contribute to a deeper understanding of GC pathogenesis and could potentially serve for early detection strategies and therapeutic interventions.