IPA identified the regulatory pathways involving the genes that distinguished leukemia cells from their stroma (AML blasts vs AML MSCs) and those that distinguished normal hematopoietic cells from their stroma (normal hematopoietic MNCs vs normal MSCs) to be: (1) TGFβ1, TNF, TGM2, C/EBPA and SMARCA4 as upstream regulators of gene expression; (2) integrin and IL-8 signaling as overrepresented canonical pathways; and (3) upregulation of the transcription factors FOS and MYB. Here, FOS is linked to leukemia.