Tumor-associated antigens (TAAs) are proteins or molecules expressed on the surface of cancer cells but are either absent or present at much lower levels on normal cells. These antigens can arise from mutations in genes or from the overexpression of normal proteins. TAAs play a crucial role in the immune system's ability to recognize and target cancer cells. The presence of TAAs can help in the development of cancer immunotherapies, which aim to enhance the body's immune response against tumors. By targeting these specific antigens, treatments can be designed to selectively attack cancer cells while sparing healthy tissues, potentially leading to more effective therapies with fewer side effects.