Thomsen–Friedenreich antigen on mucin-type glycoproteins (TF antigen)

The **Thomsen–Friedenreich antigen (TF antigen)** is a disaccharide carbohydrate structure (Galβ1-3GalNAcα1-), known as the core 1 O-glycan, that is normally cryptic (masked by further glycosylation) on healthy epithelial cell mucins but becomes exposed on the surface of mucin-type glycoproteins (notably MUC1, MUC4) in the majority of cancers[1][4]. TF antigen acts as a tumor-associated carbohydrate antigen and its exposure correlates with cancer progression and metastasis, making it a pan-carcinoma marker and a therapeutic target of interest[1]. TF antigen can modulate cell–cell and cell-matrix interactions by binding lectins such as galectin-3, promoting processes like adhesion, migration, and immune evasion in tumor cells[1]. It is commonly used as a biomarker to differentiate malignant from benign tissue and as a target for experimental glycopeptide vaccines and therapeutic antibodies, though clinical development is challenged by specificity and heterogeneity of expression[1][4].

Other names

Thomsen–Friedenreich antigenT antigencore 1 O-glycan structureGalβ1-3GalNAcα1-Ser/Thr

Inhibition of cell–galectin interactions to block metastatic adhesion Direct targeting of TF-bearing cancer cells for immune clearance (antibody-based therapies)