CD44 and neoplasm: Glypican-1 (GPC-1) may play a role in modulating immune responses by influencing cell signaling pathways involved in tumor growth and immune evasion.58–60 As a cell surface heparan sulfate proteoglycan, GPC-1 can interact with growth factors and cytokines, and promote cell proliferation and inhibit apoptosis,61,62 potentially altering the tumor microenvironment and immune surveillance.