LY6E

LY6E (lymphocyte antigen 6 complex locus E), also known as SCA2 or RIG-E, is a glycosylphosphatidylinositol (GPI)-anchored membrane protein belonging to the LY6/uPAR family. It modulates innate immune responses by enhancing type I interferon (IFN-α/β) signaling and upregulating interferon-stimulated genes (ISGs), thereby exerting dual roles in viral infections. While LY6E facilitates host defense against coronaviruses (e.g., SARS-CoV-2) and flaviviruses by restricting viral entry, it paradoxically enhances HIV-1 infectivity through envelope glycoprotein stabilization. This protein is implicated in cancer progression, particularly in breast and lung carcinomas, where it promotes metastasis via EGFR/MAPK and Wnt/β-catenin pathways. Current research focuses on LY6E-targeted therapies, including monoclonal antibodies and small-molecule inhibitors, with preclinical studies demonstrating efficacy in suppressing viral replication and tumor growth. Its tissue-specific expression and role in immune evasion make it a potential biomarker for therapeutic stratification.