HOXB6 and myelodysplastic syndrome: Functional inhibition of MSCs in MDS, leading to defective osteogenic differentiation capacity, is also mediated by TGF-β, present at increased levels in the MDS BMME (50), which cause abnormal gene expression of PITX2, HOXB6 and TBX15, leading to phenotypic and functional deficits (76).