Pro-inflammatory cytokines produced by mature leukemic cells had also direct effects on the leukemic HSPC; thus, BCR-ABL-dependent secretion of IL-6 by CML cells drives myeloid differentiation of leukemic multipotent MPP, establishing a feed-forward loop [75]. The gene discussed is ABL1; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.