Tumor-associated glycoprotein 72 (TAG-72) (TAG-72)

Tumor-associated glycoprotein 72 (TAG-72) is a high-molecular-weight, mucin-like glycoprotein that is widely expressed on the surface of most human adenocarcinomas, which led to its designation as a pan-adenocarcinoma antigen. It is characterized by the presence of the sialyl-Tn (STn) carbohydrate epitope, a product of aberrant O-glycosylation frequently observed during malignant transformation. While TAG-72 is found in over 80% of colorectal, gastric, ovarian, and pancreatic cancers, its expression in normal adult tissues is highly restricted to specific sites such as the secretory endometrium and certain fetal tissues. This stark differential expression makes TAG-72 an attractive target for diagnostic imaging and therapeutic interventions, including radioimmunotherapy, antibody-drug conjugates (ADCs), and chimeric antigen receptor (CAR) T-cell therapies. Monoclonal antibodies like B72.3 and its second-generation humanized or chimeric derivatives (e.g., CC49/minretumomab) have been extensively studied to deliver radioactive isotopes or cytotoxic payloads to tumor cells.

Other names

Panadenocarcinoma antigenTAG72Sialyl-Tn antigenSTn antigenTumor-associated glycoprotein 72

Binding to the sialyl-Tn (STn) carbohydrate epitope on the surface of adenocarcinoma cells to facilitate targeted delivery of radionuclides, toxins, or to recruit T-cells for immune-mediated destruction.