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How does immunotherapy help the immune system fight cancer?
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cancer
View through an endoscope of a polyp, a benign precancerous growth projecting from the inner lining of the colon.
Immunotherapy helps the immune system fight cancer by enhancing its ability to detect, target, and destroy malignant cells that might otherwise evade natural defenses. Because cancer cells can exploit various mechanisms to suppress immune activity or hide from detection, immunotherapy employs several strategies to overcome these barriers:1234
- Immune Checkpoint Inhibitors: These drugs block proteins (such as CTLA-4, PD-1, and PD-L1) that normally act as "brakes" on the immune system. By inhibiting these checkpoints, the treatment releases the immune system to mount a more powerful, sustained attack against tumors.123
- Adoptive Cell Transfer (e.g., CAR T-cell therapy): In this process, a patient's own T cells are collected and genetically engineered to express receptors that specifically identify and bind to antigens on cancer cells. Once infused back into the patient, these modified cells are better equipped to recognize and eliminate the cancer.153
- Cancer Vaccines: These stimulate the immune system to recognize specific tumor antigens, encouraging the body to produce a stronger, more targeted response against the cancer.13
- Monoclonal Antibodies: These can be designed to bind to specific tumor antigens, acting as a "magic bullet" to deliver therapeutic agents directly to cancer cells or to trigger immune-mediated destruction.13