The effects of the OSM: OSMR interaction are multipronged as it can alter either the function of malignant stem cell niches as observed in malignant hematological stem cells that do not express OSMR such as AML or MPNs, or directly act on malignant cells that express OSMR with further support from tumor-associated fibroblasts and endothelial cells which also express OSMR. The gene discussed is OSMR; the disease is acute myeloid leukemia.