In addition to mouse studies, we have set up an in vitro macrophage-tumor coculture system to demonstrate the increased tumoricidal activity of THP1-derived DKO macrophages against a human colon cancer line and patient-derived CRC organoids, confirming the superior capacity of Mafb/cMaf-inactivated human macrophages in nibbling and killing tumors upon M-CSF and ClearColi stimulation. The gene discussed is MAFB; the disease is neoplasm.