CXCL12 and chronic myelogenous leukemia, BCR-ABL1 positive: For example, CML LT-HSCs (as well as LSCs) secrete MIP-1, IL-6, and G-CSF to decrease the secretion of CXCL12, which is the essential chemokine for HSC maintenance (Greenbaum et al., 2013), in MSCs for its own competitive advantage (Zhang et al., 2012; Agarwal et al., 2019), whereas CML LSCs hardly need CXCL12 for its expansion.