GZMK and neoplasm: For example, breast tissues from BRCA1 and BRCA2 mutation carriers are enriched for IL17 receptor-positive (IL17R+), granulysin-positive (GNLY+) effector T cells, and granzyme K-positive (GZMK+) cytotoxic T cells, which are enriched in the microenvironment of triple-negative breast cancer (39–41), and proinflammatory triggering receptor expressed in myeloid cells 2-positive (TREM2+) macrophages, which are enriched in the microenvironment of multiple tumor types with protumorigenic activities (42–44).