CD274 and breast cancer: An additional study on EMT-6 mammary tumor implanted in mice revealed that B-cells acquire a regulatory phenotype (LAP/TGF-β1, CD80, CD86, PD-L1) after cell-to-cell interaction with cancer cells and their immunosuppressive dynamic can be counteracted by mAbs against TGF-β and PD-L1, leading to tumor shrinkage [102].