CD69 marks a subpopulation of acute myeloid leukemia with enhanced colony forming capacity and a unique signaling activation state

In acute myeloid leukemia (AML), leukemia stem cells (LSCs) have self-renewal potential and are responsible for relapse. We previously showed that, in Mll-AF9/NRAS(G12V) murine AML, CD69 expression marks an LSC-enriched subpopulation with enhanced in vivo self-renewal capacity. Here, we used CyTOF to define activated signaling pathways in LSC subpopulations in Mll-AF9/NRAS(G12V) AML. Furthermore, we compared the signaling activation states of CD69(High) and CD36(High) subsets of primary human AML. The human CD69(High) subset expresses low levels of Ki67 and high levels of NF kappa B and pMAPKAPKII. Additionally, the human CD69(High) AML subset also has enhanced colony-forming capacity. We applied Bayesian network modeling to compare the global signaling network within the human AML subsets. We find that distinct signaling states, distinguished by NF kappa B and pMAPKAPKII levels, correlate with divergent functional subsets, defined by CD69 and CD36 expression, in human AML. Targeting NF kappa B with proteasome inhibition diminished colony formation.