Since immune checkpoint inhibitors (ICIs) have tremendous potential for treating cancer, we investigated whether the DUSP2 expression was related to ICI-related biomarkers and discovered that high expression of DUSP2 was positively correlated when both T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death protein 1 (PD-1) were positive, whereas there were no statistical differences when both PD-1 and CTLA-4 were negative (Figures 7C–F). Here, PDCD1 is linked to cancer.