DICER1 and myelodysplastic syndrome: –Microenvironmental deregulation contributes to pathogenesis (98, 104)–In animal models, niche alterations can be sufficient to induce MDS (i.e., by Dicer mutations) (105)–Clonal hematopoiesis remodels the niche: in MDS xenograft models, healthy mesenchymal stromal cells cotransplanted with MDS cells adopt molecular features observed in mesenchymal stromal cells derived from MDS patients (106)