For example, anti-TIGIT treatment statistically significant delayed tumor growth in transgenic head and neck squamous cell carcinoma mouse and multiple myeloma models, which enhanced antitumor immune responses by reducing the population of regulatory T- cells (Tregs) [51, 52]. However, Chen et al. and our present study demonstrated that CD4 + T-cells were dispensable [53]. Here, CD4 is linked to head and neck squamous cell carcinoma.