To determine fibrosis and TGF-β activation in TNBC as a model, we used patient-derived xenograft (PDX) models that retain the essential features of the original patient tumors and metastasis to specific sites (HCI-001 and HCI-002) [19, 20], and thus are authentic experimental systems for studying human cancer metastasis. This evidence concerns the gene TGFB1 and cancer.