What is the mechanism of action of immunotherapy in treating cancer?

Immunotherapy operates primarily by harnessing and enhancing the body's own immune system to recognize and attack cancer cells. This approach is based on the understanding that cancer cells often evade detection by the immune system through various mechanisms, such as expressing proteins that inhibit immune responses.

By using different strategies, such as monoclonal antibodies, checkpoint inhibitors, and cancer vaccines, immunotherapy targets these mechanisms. For instance, checkpoint inhibitors block proteins that prevent T-cells from attacking cancer cells, thereby unleashing the immune system’s ability to destroy tumors.

The effectiveness of immunotherapy can lead to long-lasting immune responses, which not only target visible tumors but also help prevent recurrence by attacking any remaining cancer cells that may not be detectable at the time of treatment.

The other options do not accurately reflect the primary action of immunotherapy. Preventing tumor metastasis typically pertains more to other forms of treatment, while directly killing cancer cells is a characteristic of traditional treatments like chemotherapy or targeted therapy. High-dose chemotherapy refers to a strategy that does not engage the immune system in the same manner as immunotherapy, which fundamentally relies on utilizing and augmenting immune responses.