While PD-L1 can constitutively be expressed on tumor cells (see Figures 4B, 7A), or be upregulated on tumor cells during co-culture with activated T cells (see Figure 6C), it is important to note that cytotoxic T cells consistently upregulated PD-L1 themselves upon activation with αCD3/αCD28 BiMAb (see Figure 6B). This evidence concerns the gene CD274 and neoplasm.