MTOR and leukemia: In the present review we therefore discuss the role of the PI3K-Akt-mTOR pathway and the complexity of targeting this network in AML; we focus especially on the leukaemia-supporting mesenchymal stem cells (MSCs) that are regarded as important parts of the stem cell niches in the BM but we also describe effects of this therapeutic strategy on the AML cells as well the effects on monocytes because these immunocompetent cells also contribute to the formation of stem cell niches [3].