In CML mouse model, PD-1 was highly expressed on CML-specific cytotoxic T cells, while PD-L1 expression was higher in blast crisis CML (bcCML) than chronic phase CML (cpCML), indicating that CML cells utilized PD-L1 to avoid immune surveillance. Here, CD274 is linked to chronic myelogenous leukemia, BCR-ABL1 positive.