Abstract: ObjectiveTo investigate the anti-leukemia role of Nucleostemin（NS）specific short hairpin RNA （NS-shRNA） in nude mice xenograft tumor model. MethodsHL-60 leukemia cells at logarithmically growing phases were subcutaneouly inoculated into nude mice to make them oncogenic, then cells which were eluted, were cultured to the fifth generation. The invasiveness of HL-60 cells was detected by Transwell test. The heterogeneic nude mice xenograft tumor model of high-oncogenic HL-60 leukemia cells were established through implanting of high-invasive cells. NS-shRNA was synthesized in vitro, and intraperitoneally injected into the mice. The volumes and weights of the tumor were measured, and tumor samples were stained by HE. NS protein expression was detected by immunocytochemistry, and the apoptotic cells of HL-60 were examined by Tunel technique. ResultsA heterogeneic nude mice xenograft tumor model with high-oncogenic HL-60 leukemia cells were successfully established with uniform tumor volumes. After treated by NS-shRNA for 13 days, the tumor volumes，weight and NS protein in the tumor cells were statistically lower than those in control group. Large destroy of tumor tissue and “apoptosis character” changes appeared in treated group. A great deal of apoptotic cells were observed in tumor tissue after therapy, detected by Tunel technique. ConclusionThe anti-leukemia effects of NS-shRNA in nude mice xenograft tumor model were significant. One of the mechanisms was probably that down-regulation of NS expression induce the apoptosis of leukemia cells.