DKK1 and acute myeloid leukemia: Leukemic exosomes secreting messenger RNAs (mRNAs) to the microenvironment in AML remodel the HSC niche.(105) When mice were preconditioned with leukemic exosomes in the BM, the disease progressed more rapidly, and osteolineage cells had blunted development through the induction of Dickkopf Wnt signaling pathway inhibitor 1 (DKK1) overexpression.