Since a clonogenic capacity assay in a semi-solid media remains the gold standard technique to study the LSC function ex vivo, primary AML samples were treated with G-CSF for 18 h and a significant reduction of CFU-B colonies was observed in a dose-dependent manner upon treatment with G-CSF (Fig. 4a), suggesting that G-CSF exerts its effect at least partially on LSC function. The gene discussed is CSF3; the disease is acute myeloid leukemia.