Similar results have been observed in several other malignancies, including in malignant effusions where TGF-β propagates infectious tolerance (74), in leukemia blasts where TGF-β suppress NK cell effector activity (75), and in breast cancer where tumor-derived PGE2 and TGF-β exosomes convert myeloid cells to MDSCs to promote tumor progression and infectious tolerance (76). This evidence concerns the gene TGFB1 and breast cancer.