T cells are pivotal in the immune response against [cancer]. Cytotoxic T lymphocytes (CTLs) can directly kill cancer cells by recognizing cancer-specific antigens presented by MHC class I molecules. Helper T cells, on the other hand, release cytokines that enhance the activity of CTLs and other components of the immune system. Regulatory T cells (Tregs) can suppress immune responses and are often implicated in the [immune evasion] strategies employed by tumors.
