To investigate the mechanism of resistance to CX-5461 in Eμ-Myc lymphoma, we transplanted previously characterized p19ARF−/−; Bcormut; Eμ-Myc clone #4242 [39] into C57/BL6 mice, then treated animals with established disease with either CX-5461 or a drug-delivery vehicle until the mice succumbed to disease. The gene discussed is MYC; the disease is lymphoma.