TGFB1 and breast cancer: A direct interaction between BC cells and platelets also activates the TGF-β signaling pathway, which inhibits NK cell activation or function by suppressing mammalian target of rapamycin (mTOR) activity (Xu et al., 2018), and induces epithelial-mesenchymal transition (EMT) and immunosuppression to promote invasion and metastasis (Drabsch and Ten Dijke, 2011).