Of great interest, hematopoietic malignant cells supplemented with filtered (through a PVDF filter 0.1 μM) CM from either E. coli or S. cerevisiae-infected leukemic cell culture abolished APO866 cytotoxic activity (Fig. S2C), indicating that both microorganisms produce a soluble factor that could blunt the anti-tumor activity of NAMPT inhibitor. The gene discussed is NAMPT; the disease is neoplasm.