Lymphocyte antigen 6 family member E (LY6E) (LY6E)

Lymphocyte antigen 6 family member E (LY6E) is a glycosylphosphatidylinositol (GPI)-anchored cell surface protein belonging to the Ly6/uPAR superfamily [3, 10]. It plays a multifaceted role in human physiology, including the regulation of T-cell activation, immune signaling, and placental development through its interaction with syncytin-A [4, 10]. In oncology, LY6E is significantly overexpressed in a variety of solid tumors, such as breast, lung, gastric, and colorectal cancers, where it promotes tumor progression and immune evasion, making it a prominent target for antibody-drug conjugates (ADCs) and therapeutic vaccines [2, 4, 11]. Interestingly, LY6E also serves as a critical host factor in viral infections; while it facilitates the entry of viruses like HIV-1 and Yellow Fever, it acts as a potent restriction factor for coronaviruses, including SARS-CoV-2, by inhibiting viral-cell membrane fusion [6, 13]. The designation "LY6E peptide – no confirmed direct molecular target" likely refers to experimental therapies using LY6E-derived peptides as antigens or mimetics where the precise downstream molecular interactors or endogenous ligands remain under scientific investigation [1, 7, 14]. Current therapeutic development focuses on leveraging its high tumor expression for targeted cytotoxicity while managing potential off-target effects in normal tissues like the liver and lungs [2, 4].

Other names

TSA-1RIG-ESCA-2TSA1RIGESCA2Retinoic acid-induced gene E proteinThymic shared antigen 1Stem cell antigen 2LY6E peptide

Antibody-drug conjugate (ADC) mediated delivery of cytotoxic agents; Antigen presentation for T-cell activation; Inhibition of viral-cell membrane fusion [2, 4, 6].