We have shown that specific cytokines FLT3 ligand and TGFβ1 both of which are produced from bone marrow stromal cells synergistically induced MLL+ALL cells into chemo-resistant quiescence, and that treatment of MLL+ALL cells with inhibitors against FLT3 and/or TGFβ1 receptor partially but significantly converts them toward chemo-sensitive.
Although, positivity rate of both Smad7 and TGF-β1 in ALL group increased with presence of hepatosplenomegaly, still there was no statistical significance.