Objective: The xenograft of breast cancer model in nude mice was reproduced to investigate the influences of Huaier cream on carcinogenicity in nude mice transplanted with MCF-7, so as to provide theoretical basis for clinical treatment. Methods: Nude mice were randomly divided into experimental group and control group, 4 mice in each group. Mice of the experimental group were lavaged with 0.2 mL of Huaier cream (150 mg·mL-1), twice a day for a total of 30 days. The control group was given lavage with 0.2 mL of 0.9% saline, twice a day for a total of 30 days. The changes of tumor size and weights in nude mice were observed, the changes of pathological characteristics of transplanted tumor were observed under microscope. Results: In nude mouse tumorigenicity assay, each nude mouse developed tumor at the transplant site 3 weeks after inoculation with MCF-7 cells, with a tumor formation rate of 100%. The transplant tumors were (0.20±0.07)g and(0.57±0.32)g in the experimental groups after the experiment. And the transplant tumor was significantly lighter in the experimental groups than that of the control group, with statistically significant differences (P<0.01). Tumor volumes were (0.32±0.74)cm3 and (0.84±0.62)cm3, and those of the experimental groups were smaller than those of the control group, with statistically significance differences (P<0.01). HE staining showed in the nude mice of the experimental groups, there were different degrees of degeneration in the tumor cells, and large necrotic area in the central and the margin cells, especially in the area rich in blood supply, and residual tumor cells were visible around the necrosis focal; while in the control group, the cells were well grown, with atypia, in irregular shape and size, and the nuclei were large and densely dyed, pathological karyokinesis phase was seen, but no obvious necrotic area was found. Conclusion: In nude mice, Huaier cream can inhibit the tumor formation of MCF-7 cells, possibly due to the function of Huaier cream inhibiting the growth of breast cancer cells.
 FAN L,STRASSER-WEIPPL K,LI J J,et al.Breast cancer in Chian[J].Lancet Oncol,2014,15(7):e279-e289.
 LU M Q,KONG Q Z,XU X H,et al.Pectolinarigenin,a flavonoid compound from cirsium japonicum with potential anti-proliferation activity in MCF-7 breast cancer Cell[J].Trop J Pharm Res,2014,13(2):225-228.
 ZHANG T,WANG K,ZHANG J,et al.Huaier aqueous extract inhibits colorectal cancer stem cell growth partially via downregulation of the Wnt/beta-catenin pathway[J].Oncol Lett,2013,5(4):1171-1176.
 ZHANG F,ZHANG Z,LIU Z.Effects of Huaier aqueous extract on proliferation and apoptosis in the melanoma cell line A875[J].Acta Histochem,2013,115(7):705-711.
 WANG X,ZHANG N,HUO S,et al.Huaier aqueous extract suppresses human breast cancr cell profliferation through inhibition of estrogen receptor αsignaling[J].Int J Oncol,2013,43(1):321-328.