LGALS9 and breast cancer: Furthermore, the soluble form of TIM-3, which inhibits the activation of both NK cells and cytotoxic T lymphocytes [41], was reported to be lower in breast cancer patients compared with healthy controls [41,42], probably because of the binding of the soluble TIM-3 form to TILs in breast cancer patients [41] or due to the binding of the TIM-3 receptor to the galectin-9 ligand expressed on the tumor cell surface, making the tumor-associated TIM-3-galectin-9 complex unlikely to be secreted.