TCF7 and cancer: Altogether, these observations demonstrate that, in different human cancer types, tumor-specific CD8+ TILs co-exist in three distinct subtypes: a cytotoxic TOX-high exhausted subtype; its TOX-high TCF7-high exhausted precursor, quiescent and characterized by lower cytotoxicity; and a precursor subtype that does not display the hallmarks of tumor-specific TILs but resembles blood-circulating effector memory T cells.