Oncofetal Carbohydrate Antigens

Oncofetal carbohydrate antigens are a class of carbohydrate structures that are typically present during fetal development but are aberrantly re-expressed or overexpressed in adult cancers. These motifs are often found on glycoproteins and glycolipids on the cell surface and play crucial roles in various cellular processes, including signal transduction, cell proliferation, adhesion, and metastasis, contributing to tumor growth and dissemination. Their restricted expression in healthy adult tissues, coupled with their high prevalence and functional significance in tumors, makes them attractive therapeutic targets and diagnostic biomarkers for a wide range of cancers, including colorectal, breast, pancreatic, and neuroblastoma. Therapeutic strategies targeting oncofetal carbohydrate antigens include immunotherapies like CAR T cells and vaccines, which aim to elicit an immune response against cancer cells. Additionally, these motifs are utilized for targeted drug delivery, where anticancer agents are conjugated to carbohydrate ligands to selectively deliver drugs to tumor cells. They also serve as important biomarkers for cancer detection, diagnosis, monitoring treatment response, and prognosis, with examples such as CA19-9, CA125, and oncofetal chondroitin sulfate.

Other names

Oncofetal antigensTumor-associated carbohydrate antigens (TACAs)Tumor glycocodeAberrant glycosylation patternsOncofetal chondroitin sulfate (ofCS)CA19-9CA125GD2GD3SSEA-4Stage-Specific Embryonic Antigen (SSEA)-0

Oncofetal carbohydrate antigens are targeted through various mechanisms. Immunotherapies, such as CAR T cells and vaccines, aim to induce a specific immune response against cancer cells expressing these aberrant carbohydrate structures, leading to tumor cell destruction. Monoclonal antibodies can directly bind to these antigens, marking cancer cells for immune clearance or interfering with their function. Targeted drug delivery systems, including glycoconjugate prodrugs and recombinant VAR2CSA proteins, exploit the overexpression of these motifs or associated sugar-binding receptors on cancer cells to selectively deliver cytotoxic agents, thereby enhancing efficacy and reducing systemic toxicity. Additionally, inhibitors of carbohydrate processing enzymes, such as glycosidases, can disrupt the synthesis of these aberrant glycans, thereby impeding tumor growth and metastasis.