MPZL1 is a cell surface receptor of the immunoglobulin superfamily that functions as a key mediator of cancer progression across multiple tumor types. Structurally, MPZL1 contains an immunoglobulin variable-like extracellular domain with a critical N-linked glycosylation site at Asn50 that mediates concanavalin A binding 1. The protein exists as a homodimer, with dimerization potentially regulating signal transmission 1. Mechanistically, MPZL1 promotes tumor cell migration and metastasis primarily through Src-mediated phosphorylation of cortactin 2, and activates SHP2/SRC/β-catenin-dependent signaling pathways 3. MPZL1 expression is frequently upregulated in hepatocellular carcinoma, gallbladder carcinoma, non-small cell lung cancer, and mesothelioma, often due to gene amplification 245. High MPZL1 expression correlates with advanced tumor stages, aggressive behavior, and poor prognosis 64. In lung adenocarcinoma, MPZL1 enhances proliferation, invasion, and migration while suppressing CD8+ T cell infiltration 7. Clinically, MPZL1 and its ligand progastrin represent therapeutic targets; blocking PZR with monoclonal antibodies inhibited colorectal cancer stemness and adenoma formation in preclinical models 3.