TNF and cancer: As an immunotherapeutic option, cytotoxic T lymphocytes (CTLs) can selectively induce apoptosis in target cells via perforin/granzyme and Fas/tumor necrosis factor-mediated mechanisms, further serving as potential candidates for the treatment of cancers (10, 11); in fact, several previous studies have revealed the potential of CTLs to target specific types of cancer stem cells (CSCs), such as colon lung CSCs (12, 13).