Therefore, compared with KLRG1−CD8 T cells, higher expression of heparanase might contribute to the migration of KLRG1+CD8 T cells into tumor sites, where KLRG1+CD8 T cells could exert stronger cytotoxicity against tumor cells in FasL- and Granzyme B-dependent manners. The gene discussed is GZMB; the disease is neoplasm.