TGFB1 and chronic myelogenous leukemia, BCR-ABL1 positive: Furthermore, bone marrow resident cells support CML LSCs persistence by releasing various soluble substances such as JAGGED1 (a Notch ligand), TGF-β, bone morphogenic proteins (BMPs), chemokines, CXCL12, IL-1, and exosomes containing miR-126 [61].