Interestingly, among the CXCL12+ MSCs supporting CSC maintenance, Prx1+ MSCs negatively regulate CSC proliferation, and when CXCL12+ Prx1+ MSCs were depleted, chronic myeloid leukemia CSC self-renewal was enhanced and blood cancer cells increased proliferation and expansion, while HSC proliferation decreased. Here, CXCL12 is linked to chronic myelogenous leukemia, BCR-ABL1 positive.