CXCR4 and chronic myelogenous leukemia, BCR-ABL1 positive: Recent report found CXCR4 up-regulation by imatinib induces chronic myelogenous leukemia cell migration to bone marrow stroma and promotes survival of quiescent CML cells (Jin et al., 2008), while MSCs-derived Gas6 and N-cadherin stabilize or increase β-catenin levels in CML stem cells with or without TKIs and enhance maintenance of CML LSCs with anti-apoptosis and repopulating capacity (Zhang et al., 2013; Jin et al., 2017); inhibition of WNT/β-catenin signaling of MSCs prevents the development of MDS (Stoddart et al., 2017).