Tumorantigens

Tumorantigens are molecules expressed on the surface of cancer cells that can be recognized by the immune system. They are essential for the development of strategies that aim to clear malignant cells by harnessing the body’s own defenses.

The term covers two interconnected groups. Tumor‑associated antigens (TAAs) are normally present at low levels in healthy tissues but are overexpressed or aberrantly expressed in tumors. Tumor‑specific antigens (TSAs) arise from unique processes such as frameshift mutations or viral integration and are not found in normal cells. Both types are presented by major histocompatibility complex (MHC) molecules to T cells and B cells, initiating adaptive immune responses.

The recognition of tumorantigens is a key step in cancer immunosurveillance. Failure to eliminate cells bearing these markers allows malignant clones to expand. Conversely, deliberate activation of antigen‑specific immunity can lead to tumor regression, a principle that underlies many modern therapies.

Clinical investigations have identified several prominent tumorantigens. Examples include NY‑ESO‑1 and MAGE‑A4, which are restricted to many solid tumors, and WT1, which is commonly overexpressed in leukemias. The epidermal growth factor receptor variant HER2/neu is a membrane protein over expressed in breast and ovarian cancers and also functions as a tumorantigen.

Therapeutic approaches that target tumorantigens range from peptide vaccines to engineered T‑cell receptors and chimeric antigen receptor (CAR) T‑cell products. Continued research into antigen discovery and escape mechanisms is refining these strategies and improving patient outcomes.