To investigate the role of β-AR signaling in the efficacy of chemotherapy in hematologic malignancies, wildtype (WT) mice were injected intravenously (i.v.)with the lymphoma cell line EL4 followed by a suboptimal dose (day 7; i.v.; 4 mg/kg) of doxorubicin alone or with propranolol (daily; i.p.; 1 mg/kg). The gene discussed is ADRB2; the disease is lymphoma.