CD274 and neoplasm: Using the cell killing assay, we observed that the 4T1 cells with PD‐L1/CD44 blockade were immune to TriTNE‐mediated tumor killing and that the use of single CD44 or PD‐L1 blockade led to significantly lower levels of TriTNE‐mediated tumor cell killing than the use of isotype antibody in treated 4T1 cells (Figure 2K).