Self-production of IFN-γ by acute myeloid leukemia cells remodels mesenchymal stromal bone marrow cells

Acute myeloid leukemia (AML) cells can shape their niche to their own advantage, perturbing bone marrow stromal and immune landscape. Indeed, AML cells provide the signals, among which inflammatory mediators are crucial, since they are able to subvert mesenchymal stromal cell (MSC) funtions. In particular, IFN-γhigh AML cells hold an inflammatory/immune modulating signature distinct from IFN-γlow cases. We analyzed changes in the gene expression profile of MSCs induced by co-culture with AML cells in vitro. IFN-γhigh but not IFN-γlow AML cells profoundly subverted the MSC transcriptome by inducing immune-modulating pathways, which, intriguingly, included IFN-γ-dependent genes related to regulatory T cell (Treg) differentiation and immune suppression. MSCs cultured with AML cells (on a transwell) for 24h (or control MSCs cultured without AML cells under the same conditions) were used for RNA extraction and hybridization on microarrays.