Background and aims: Researches about blocking angiogenesis to treat tumor have become one of the most promising and active fields in anticancer research. This study aimed to investigate the eukaryotic expression of extracellular ligand binding domains of murine Tie-2 and its anti-angiogenesis effect.
Methods: A eukaryotic expression vector pcDNA3.1(+) integrating with a DNA fragment which encode extracellular ligand binding domains of murine Tie-2 was transfected into SGC-7901 gastric cancer cell line. The protein expression was detected by western blot analysis and immunocytochemistry staining. Following the construction of nude mouse tumor xenograft model with and without transfected cells, tumor microvessel density was determined by counting per high power field in the sections stained with an antibody to CD31 to test its inhibition of angiogenesis.
Results: The extracellular ligand binding domains of murine Tie-2 receptor was highly expressed in SGC-7901 gastric cancer cells with plasmid transfection. The mean tumor sizes of groups with and without transfection were 1.27 +/- 0.35 and 1.75 +/- 0.17 cm(3), respectively (P = 0.025). The mean inhibitory rate of tumor was 27.18 +/- 19.93%. The comparison between highest microvessel density of group with transfection (14.00 +/- 3.80) and that of group without transfection (22.30 +/- 5.91) was statistically significant at P = 0.030.
Conclusion: The protein of extracellular ligand binding domains of murine Tie-2 can be expressed at high level in the eukaryotic expression system, and the expressed protein may have the anti-angiogenesis effect.