Hu Ji-wei¹, Yan Jin-yin¹, Wang Ya-qi^{1, 2}, Zhang Jing-hua^{1, 2,}, Wang Lei³, Li Yu-feng⁴, Liu Yan^{4, 5}, Ma Jie¹, Li Ning¹, Zhang Shun-li¹, Gu Zheng¹, Wang Hong¹

Objective: To investigate the antitumor angiogenesis activity of Mfn2 gene on a heterologous graft model for human breast infiltrating duct carcinoma in nude mice. To investigate the relationship between Mfn2 gene and Epidermal Growth Factor Receptor (EGFR). Methods: Human breast cancer MCF-7 cells steady infected with Mfn2 gene had been constructed. Western blotting was used to detect the overexpression of Mfn2 protein. Then the MCF-7 cells were injected subcutaneously into the breast pad of nude mice. Tumorigenicity and the growth of transplanted tumor in nude mice were observed. Growth curves were plotted based on mean tumor volume in each experimental group at the indicated time points. Meanwhile, the negative control group (NC group) which MCF-7 cells steady infected with PEGFP-N1 was set up. The expression of CD34 (reflect the microvessel density of tumor) and EGFR were detected by immunocytochemistry. Results: The tumor volume of the experimental group was smaller than the negative control group.The expression of CD34 of the experimental group was lower than the negative control group. The experimental group expressed low level of EGFR. Conclusion: Mfn2 significantly inhibits the growth of human breast cancer xenograft in nude mice. Downregulation of EGFR expression and decrease the potential of angiogenesis may be the potential mechanism.

breast cancer, EGFR, Mfn2, nude mice