Tumor antigen presented on major histocompatibility complex (null)

Tumor antigens presented on major histocompatibility complex molecules are peptide fragments derived from proteins that have undergone mutation, aberrant post-translational modification, or atypical processing in cancer cells. These peptides are loaded onto MHC class I (for CD8+ T cell recognition) or class II molecules (for CD4+ T cell recognition) and expressed on the plasma membrane, where they enable the immune system to identify and destroy malignant cells. The diversity and specificity of presented antigens are regulated by the highly polymorphic nature of MHC genes, and defects in this pathway are a major mechanism for tumor immune evasion. This axis is central to several modern immunotherapeutic approaches, including immune checkpoint blockade and neoantigen-targeted therapy. Detection and targeting of tumor-presented antigens remain key strategies to enhance anti-cancer immunity, although challenges such as tumor heterogeneity, antigen loss, and risk of autoimmunity remain.

Other names

Tumor antigen–MHC complexTumor-derived peptides presented by MHCCancer neoantigen–MHC complexMHC-restricted tumor antigens

Enhancement of T cell recognition and cytotoxicity against tumor cells displaying specific antigens on MHC; Restoration or upregulation of antigen presentation (increases tumor visibility to T cells); Overcoming immune evasion by restoring MHC expression/function; Direct targeting of mutant neoantigen peptides by engineered T cells or antibodies