Confirming its biological activity in vivo, three doses of 50 mg kg−1 Thiostrepton i.v. effectively downregulated FOXM1 in xenografted ALL in vivo while it did not affect the expression of forkhead box transcription family members FOXO1 and FOXO3a (Fig. 7k). The gene discussed is FOXO1; the disease is acute lymphoblastic leukemia.