CEACAM1 and head and neck carcinoma: Furthermore, new findings indicated the expression of TIM-3 and its ligand CEACAM1 on both CD4+ and CD8+ TILs could protect T cells from apoptosis, promote the expansion of the immunosuppressive cell population, but also induce T cell exhaustion (Zöller et al., 2020; Dixon et al., 2021; Yang et al., 2021), suggesting that anti-TIM-3/CEACAM1 axis therapy is promising candidate for combination with other therapeutic modalities diminish regulatory T cells or co-stimulate CD8 T cells to treat head and neck carcinoma.