HO1-inhibiting T-hNP (T-hNP/SnMP) increased chemo-sensitivity in leukemia cells, while in a human-AML-bearing orthotopic animal model, intravenously administered T-hNP not only actively targeted leukemia cells, but passively targeted CD11b+ myeloid cells in the BM niche (Figure 2). Here, HMOX1 is linked to acute myeloid leukemia.