Tumor antigens recognized by TCRs, NK receptors, and NKT cell receptors on malignant cells (Tumor Antigens)

Tumor antigens recognized by TCRs, NK receptors, and NKT cell receptors represent a diverse group of molecules expressed by malignant cells that trigger immune recognition. This category encompasses neoantigens derived from somatic mutations, overexpressed self-antigens, cancer-testis antigens, and stress-induced ligands like MICA/B. T-cell receptors (TCRs) typically recognize processed peptide fragments presented by Major Histocompatibility Complex (MHC) molecules, while Natural Killer (NK) cell receptors detect stress-induced or downregulated MHC molecules, and Natural Killer T (NKT) cells recognize lipid antigens presented by CD1d. In oncology, these antigens are the fundamental targets for immunotherapy, including vaccines, adoptive cell transfers, and checkpoint blockade. Their role in disease is central to the concept of immunosurveillance, where the immune system identifies and eliminates nascent tumors based on the presence of these non-self or altered-self markers. Therapeutic strategies aim to enhance the visibility of these antigens or bypass tumor-mediated immunosuppression to achieve durable clinical responses.

Other names

Tumor-associated antigensTumor-specific antigensCancer antigensNeoantigensTumor-derived ligands

These antigens are targeted via various modalities including immune checkpoint inhibitors that reinvigorate T-cell responses against peptide-MHC complexes, CAR-T cell therapies engineered to recognize surface antigens, and monoclonal antibodies that facilitate antibody-dependent cellular cytotoxicity (ADCC) by NK cells.