Our observations, along with the previous studies that targeting two or more inhibitory pathways can strengthen tumor-specific CTLs responses in cancer [29, 30], presented the possibility that simultaneous blockade of PGE2 and PD-1 signaling pathways may verify the most effective way to rescue the immunodominant CTLs from exhaustion in the presence of chronic antigen exposure. Here, PDCD1 is linked to neoplasm.