IL2 and neoplasm: Combination therapy with GQD and anti-mouse PD-1 led to the downregulation of PD-1, but increased the proportion of CD8+ T cells in peripheral blood and tumor tissues as well as the expression of IFN-γ and IL-2 in tumor tissues, suggesting that a combination therapy could effectively restore T-cell functions by suppressing the inhibitory checkpoints (Lv et al., 2019).