PDCD1 and central nervous system cancer: In the CT2A tumor model, the median survival times of Δ10 3′-UTR ZIKV, anti–PD-1, and PBS treatment with isotype controls were 24 days, 25 days, and 22 days, respectively (Figure 5D), suggesting little benefit of immune-sensitized virus treatment alone on survival of these glioma-bearing mice.