Suppression of the tumor in nude mice bearing orthotopic breast cancer after CNHK600-EGFP or CNHK600-IL24 was injected by tail vein. Log phase MDA-MB-231-luc cells were injected into the fat pad of nude mice. At 14, 16, 18, 20 and 22 days after the injection of cells, viruses were administered through intravenous injection at the dose of 2 × 108 pfu (CNHK600-EGFP and CNHK600-IL24 middle). The doses for CNHK600-IL24 low and high group were 1× 108 and 4× 108 pfu respectively. Luminescent images were visualized every week (A), Photon counts (B) and tumor volume (C) were also measured. Mice were sacrificed and tumor weight was measured on day 42 (D). Mouse serum was collected on day 42 after orthotopic tumor cell inoculation. IL24 level was measured by ELISA (E) and serum ALT level was also quantified (F) (N = 5 for each group).