CD274 and breast cancer: CAF-derived exosomes promote miR-92 expression in BC cells. miR-92 targets LATS2 and enhance the nuclear translocation of YAP1. The nuclear translocation of YAP1 leads to increased transcription and expression of PD-L1 in breast cancer cells.After treatment of BC cells by CAF-derived exosomes, cancer cells express higher PD-L1.