TIGIT and colorectal cancer: The engagement of TIGIT with CD155 prevents human NK cytotoxicity and cytokine production; this is made possible by counterbalancing DNAM-1 mediated activation, which can be reversed by antibody-mediated TIGIT blockade.106,107 The blockade of TIGIT makes NK cells resistant to inhibition by myeloid-derived suppressor cells.96,108 In like manner, a recent study showed that downregulated TIGIT expression inhibited the proliferation of colorectal cancer cells.37,109,110