| Objective: Although it has reported that surgical trauma could promote tumor metastasis, mechanisms are still not fully elucidated. The aim of this study was to examine the relations between surgical trauma promoting pulmonary metastasis in a model and the expression of host MMP-9 and VEGF during the process. Methods: Mice with tumor burden were divided into three groups: control group received no treatment; surgery group only received tumor excision alone; sham surgery group received sham surgery. Serum MMP-9 expression and activity were detected continuously by zymography. At the end points, mice were necropsied and organs were examined for surface metastases using a dissecting microscope. Tissue sections were stained with H&E and examined by light microscopy for metastases. Elisa assay was used to examine the serum host MMP-9 and VEGF. Results: During days 1 to 3 after surgery, serum host Pro-MMP-9 level in sham group and in surgery group was higher than in control group; however, during days 19 to 47 after surgery, the level in sham group was higher than in control group and in surgery group (P＜0.05), no difference between control and surgery group (P＞0.05). Metastases were only found on the lung surface. By H&E staining, the numbers of metastases per mouse in sham group were higher than in control group (P＜0.05). The expression of host Pro-MMP-9 in serum is positively correlated with tumor size and numbers of metastases respectively. Within tumor, VEGF expression in sham group was higher than in control group, but lower than in control group (P＜0.05). Conclusion: Surgical trauma could promote tumor pulmonary metastasis, and the underling mechanisms may involve in its promoting host Pro-MMP-9 and VEGF expression and prolonging host Pro-MMP-9 expression by inducing the mutual action between tumor and host.
|
PDF Full Text Request