Interestingly, those MDS subgroups that displayed the highest resistance to HTR1 antagonists (MDS-5Q and MDS-RS-MLD) showed the highest differentiation induction upon treatment (CD11b expression in MDS-5Q: 143.70 ± 20.22; MDS-RS-SLD: 79.35 ± 2.774; MDS-MLD: 138.10 ± 19.31; MDS-RS-MLD: 186.40 ± 43.79; MDS-EB-1/2: 116.10 ± 17.85). This evidence concerns the gene ITGAM and myelodysplastic syndrome.