Tumor-associated carbohydrate antigen-peptide complex (TACA-peptide complex)

Tumor-associated carbohydrate antigen-peptide complexes, also known as tumor-associated glycopeptide antigens, are specialized epitopes found on the surface of cancer cells, resulting from the aberrant glycosylation of cell-surface glycoproteins (PubMed: 25611150). In healthy cells, glycoproteins like mucins undergo extensive and complex glycosylation; however, in malignant cells, this process is often truncated or altered, leading to the exposure of short carbohydrate chains such as the Tn, sialyl-Tn (STn), or Thomsen-Friedenreich (TF) antigens on the protein backbone (PubMed: 22230530). These complexes are highly specific to tumors because the unique spatial arrangement of the carbohydrate and the underlying peptide sequence creates a neoepitope that is absent or sequestered in normal tissues (PubMed: 26459116). They play critical roles in cancer progression by facilitating cell-cell adhesion, promoting metastasis, and aiding in immune evasion by masking protein epitopes or interacting with inhibitory receptors (PubMed: 25231120). Therapeutically, these complexes are targeted by monoclonal antibodies like gatipotuzumab, antibody-drug conjugates (ADCs) such as DS-3939, and cancer vaccines like MAG-Tn3, which aim to harness the immune system to selectively destroy cells expressing these aberrant glyco-signatures (PubMed: 23403610, Daiichi Sankyo). Clinical evaluations focus on their potential to treat a wide range of epithelial cancers, including breast, ovarian, and lung carcinomas.

Other names

Tumor-associated glycopeptide antigenTumor-specific glycopeptide epitopeTA-MUC1Mucin-1 glycopeptideTn-peptide complexSTn-peptide complexGlyco-mucin

Antibody-dependent cellular cytotoxicity (ADCC), antibody-drug conjugate (ADC) mediated intracellular delivery of cytotoxins, and induction of humoral and cellular immune responses through glycopeptide-based vaccines.