A T cell immunoreceptor with Ig and ITIM domains (TIGIT) has emerged as a compelling negative regulator of cytotoxic lymphocytes and represents an attractive target for cancer therapy, potentially offering a reduced risk of irAEs compared to anti-PD-1 or anti-CTLA-4 monoclonal antibodies (mAbs) [129,130]. Here, PDCD1 is linked to cancer.