Breast cancer tumor antigens

Breast cancer tumor antigens are proteins expressed on breast cancer cells that can be targeted by the immune system or therapeutic interventions. The most well-characterized breast cancer antigen is Human Epidermal Growth Factor Receptor 2 (HER2), which is overexpressed in approximately 15-20% of breast cancers[5][6]. HER2 is a 185-kDa protein receptor with tyrosine kinase activity that plays a crucial role in cell proliferation and survival[1]. Other important breast cancer antigens include Carcinoembryonic Antigen (CEA), Mucin 1 (MUC-1), carbohydrate antigens (Tn, TF, STn), p53, telomerase reverse transcriptase (TERT), and Wilms' tumor 1 (WT1)[1]. These antigens can be classified as tumor-associated antigens (TAAs), which are self-proteins abnormally expressed in cancer cells, or tumor-specific antigens (TSAs), which are unique to cancer cells[3]. Neoantigens, a type of TSA arising from somatic mutations, are particularly important in breast cancer immunotherapy. Triple-negative breast cancers (TNBC) typically have a higher neoantigen burden compared to hormone receptor-positive (HR+) breast cancers, which correlates with increased immune infiltration and better response to immunotherapy[4]. Targeted therapies against breast cancer antigens include monoclonal antibodies like trastuzumab, which binds to the extracellular domain of HER2 and blocks its activation[5][6]. These targeted approaches have significantly improved outcomes for patients with HER2-positive breast cancer. The molecular classification of breast cancer based on antigen expression (HER2, ER, PR, Ki-67) helps guide treatment decisions and predict prognosis[6].

Other names

Tumor-associated antigens (TAAs)Tumor-specific antigens (TSAs)Breast cancer neoantigens

Antibody-dependent cell-mediated cytotoxicity; Blocking of signaling pathways; Inhibition of cell proliferation; Enhancement of immune recognition; Induction of cancer cell death