Fig. 6

sFLT1 expression in choriocarcinoma cells significantly reduces in vivo tumorigenic activity. The stable sFLT1-i13- or GFP-expressing JEG-3 cells were designated as JEG3-i13 and JEG3-GFP, respectively. a Quantitation of tumor size in JEG3-i13- or JEG3-GFP-implanted groups. b A significant decrease in the size of tumor nodules derived from JEG3-i13 cells at day 15 after subcutaneous injection into nude mice. Arrowheads indicate the tumors grown at injection sites. c The mean weight of tumors. d Immunohistochemical analysis of microvessel formation in tumors. The microvessels were shown as a brown color when stained using anti-mouse CD31 monoclonal antibody. e Quantitative analysis of microvessel density in tumors. Scale bar: 50 μm. All values represent the mean ± SD. Asterisks indicate a significant difference (P < 0.05)