Solid tumor-associated antigen (TAA)

Solid tumor-associated antigens (TAAs) represent a diverse group of molecules, primarily proteins, glycoproteins, or glycolipids, that are expressed on the surface or within the cytoplasm of solid tumor cells (NCI, 2023). While these antigens are not strictly unique to malignant cells—often being expressed at lower levels in normal tissues or during embryonic development—their significant overexpression in tumors makes them viable targets for precision medicine (Vigneron, 2015). TAAs play various roles in tumor biology, including promoting cell proliferation, survival, and metastasis, as seen with targets like HER2/neu or EGFR (Abbas et al., 2021). In the context of drug development, TAAs are the primary targets for monoclonal antibodies, antibody-drug conjugates (ADCs), and T-cell-based therapies such as CAR-T cells (Pardoll, 2012). The therapeutic challenge associated with TAAs is the potential for on-target, off-tumor toxicity, necessitating the identification of antigens with the highest possible differential expression between cancerous and healthy tissues (Hinrichs & Restifo, 2013). Consequently, TAAs are central to the design of modern oncology pipelines, serving as both therapeutic anchors and diagnostic biomarkers (Slamon et al., 2001).

Other names

Tumor-associated antigenCancer-associated antigenOncofetal antigenTumor antigenSolid tumor antigen

Drugs targeting these antigens typically function through antibody-dependent cellular cytotoxicity (ADCC), delivery of cytotoxic payloads via antibody-drug conjugates (ADCs), redirection of T-cells (BiTEs), or direct inhibition of signaling pathways (NCI, 2023; Pardoll, 2012).