The dual roles of CD24 in tumorigenesis and immune evasion

CD24 is a glycosylphosphatidylinositol (GPI)-anchored protein overexpressed in multiple malignancies, where it drives tumor progression through diverse oncogenic signaling pathways. Beyond its established roles in promoting proliferation, metastasis, and immune evasion, emerging evidence reveals context-dependent functions including paradoxical tumor-suppressive effects in specific cancer subtypes. This review synthesizes current understanding of CD24's multifaceted contributions to tumorigenesis, examining its regulatory mechanisms, signaling networks, and therapeutic targeting strategies. We address critical unresolved questions regarding the integration of transcriptional and post-translational regulation with context-dependent oncogenic functions, the mechanistic bases for CD24's nuclear localization and paradoxical roles, and the therapeutic implications of targeting CD24-mediated immune evasion pathways.