Tumor-associated antigens on colorectal cancer cells (CRC-TAAs)

Tumor-associated antigens (TAAs) on colorectal cancer (CRC) cells represent a heterogeneous group of molecules, primarily proteins and glycoproteins, that exhibit significantly higher expression levels on malignant cells compared to healthy colonic tissue. Common examples include Carcinoembryonic Antigen (CEA), Epithelial Cell Adhesion Molecule (EpCAM), and Guanylyl cyclase C (GUCY2C), which often play roles in cell adhesion, signal transduction, and fetal development (PMID: 31513354, UniProt P06731). In the context of colorectal cancer, these antigens serve as critical targets for targeted therapies, including monoclonal antibodies, antibody-drug conjugates, and emerging cellular immunotherapies like CAR-T cells (PMID: 26912457). While TAAs are valuable for directing treatment, their utility is often challenged by 'on-target, off-tumor' effects where drugs attack normal tissues expressing low levels of the same antigen. Beyond therapy, these antigens are frequently used as clinical biomarkers; for instance, monitoring serum CEA levels is a standard practice for detecting disease recurrence and assessing treatment response in CRC patients (PMID: 33801015).

Other names

Colorectal cancer-associated antigensCRC surface antigensOncofetal antigensTumor-specific antigensCRC-associated surface proteins

Therapeutic agents targeting these antigens utilize various mechanisms including antibody-dependent cellular cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), inhibition of ligand binding to receptors (e.g., EGFR), and the delivery of cytotoxic payloads via antibody-drug conjugates (ADCs). Chimeric antigen receptor (CAR) T-cells and bispecific antibodies are also designed to recognize these antigens to induce direct T-cell mediated lysis of colorectal cancer cells (PMID: 33801015, PMID: 30613340).