Reproduction of human endometriosis in nude mouse to test the effects of endostatin therapy

Objective To reproduce the human endometriosis (EMS) in nude mouse, and to asssess the effects of endostatin in this model. Methods Endometrium tissue was collected from four women undergoing hysterectomy for EMS, and it was transplanted into 30 female BALB/c nude mice by subcutaneous injection (n=20) and intraperitoneal injection (n=10) respectively. The development of endometriotic lesions in nude mice was observed three times every week. Two weeks later, the successful rate in the two groups was estimated. The model mice in subcutaneous injection group were then randomized into treatment group (n=8) and control group (n=7). The mice in treatment group were injected with human endostatin (2mg·kg -1 ·d -1 ), while the mice in control group received an equivalent volume of PBS. All mice were sacrificed 14 days after treatment. Immunohistochemistry was used to determine the expression of vascular endothelial growth factor (VEGF). Results Transplantation was successful in 7 nude mice in abdominal implantation group and 15 nude mice in subcutaneous injection group. The success rate was 75% in subcutaneous injection group and 70% in abdominal implantation group, no significant difference was found between two groups. The level of VEGF in the nude mice treated with endostatin was significantly lower than that in the control group (P0.05). Conclusions Endostatin can effectively interfere with the development of EMS by inhibiting angiogenesis and reduce the expression of VEGF in ectopic lesion, implying that endostatin might be used in the treatment of endometriosis.