CD274 and neoplasm: Compared with HepG2.2.15 tumour‐bearing mice, HepG2.2.15‐BMP9‐MB tumour‐bearing mice, which showed increased tumour vessel perfusion (Figure 7B, Supporting Information Figure S8H,I), exhibited decreased tumour growth after treatment with NK cells and the PD‐L1 inhibitor (Figure 7C‐E).