These antigens can be proteins orpeptides derived from cancer-specific or tumor-associated antigens.26 Some of the activated Jurkat T cells differentiateinto cytotoxic T lymphocytes (CTLs), which are specialized in killingtarget cells, including cancer cells.26 CTLs release cytotoxic molecules, such as perforin and granzymes,to attack cancer cells. This evidence concerns the gene PRF1 and cancer.