Expression and significance of KISS-1 and MMP-9 gene in endometriosis model of nude mice

Objective: Based on the establishment of nude mice endometriosis model, we detected the expression of KISS-1 and matrix metalloproteinase-9 (MMP-9) gene in the ectopic endometrial tissues, and discussed the interaction between the genes. Methods: Normal human late secretory endometrium was put into abdominal cavity of nude nice to establish nude mice endometriosis (EM) model. Nude mice were killed 5, 10, 15, and 30 days later separately. The ectopic growth endometrium was obtained. The normal human late secretory endometrium was as control. Reverse transcript polymerase chain reaction (RT-PCR) was used to examine the KISS-1 mRNA and MMP-9 mRNA expression and their relative levels. Results: In 5 d, 10 d, and 15 d groups, lower level of KISS-1 was expressed than that in control group (P 0.05). The expression in 30 d group had no difference with the control group (P0.05). However, in 5 d, 10 d, 15 d, and 30 d groups higher level of MMP-9 was expressed than that in control group (P0.05). In 15 d group, the expression was the highest (P0.05). In addition, the negative correlation was observed between the expression of KISS-1 mRNA and MMP-9 mRNA (r=-0.575, P0.01). Conclusion: The decreased expression of KISS-1 gene and the increased expression of MMP-9 gene may be involved in the invasion of EM and may play an important role in the genesis and development of EM.