Expression And Significance Of MMP-2,TIMP-2 In Recurrent Aphthous Ulcer

ObjectiveRecurrent aphthous ulcer(RAU)was one of most frequently occurring oral mucosa disease,the incidence was about 20%.Its histopathological characteristic was the edema of inner epithelial cells and among epithelial cells,the epidermis dissolved, broken,falled off and ulcer was formed at last.Pseudomembrane was formed dued to the fiber exudation from face of ulcer,the collagen of connective tissuel appeared disorganization.Chronic immunity inflammation including lymphocytes and plasma cells infiltrating existed in lesions district,Capillary had been expansed,endothelial cell of blood vessel had been swelled.Matrix metalloproteinase-2(gelatinse),composed and secreted by epithelial cells, degradedⅣcollagens of ECM.It played an important role in the growth,infiltration, transfer and the inner blood vessel production of the tumor and influenced the promotion of local and body immunoreactions.At the meantime,it was controlled and affected by intracellular and extracellular factors.TIMP-2 was the natural tissue inhibitors of MMP-2 that existed in human body.The present study aimed to measure the expression of MMP-2,TIMP-2mRNA and protein in RAU tissues and examine the relation between MMP-2,TIMP-2 and the clinical types of the specimens in RAU,explore the expression of MMP-2 and TIMP-2 in RAU tissues and their biologic significance,investigate the mechanisms in the RAU and provide some theoretic basis for the effective treatment. MethodsThirty-six patients with RAU were collected and classified into 3 groups according to the clinical and pathological diagnose:MIAu,HU and MjAu.Meanwhile, specimens from oral mucosa in five normal persons were also collected as controls. Immunohistochemistry and RT-PCR technique were used to examine the expression of MMP-2,TIMP-2 at the level of protein and mRNA,ANOVA was used to analyze the integral optical density and relative density.Results1.Immunohistochemical stainingThe staining was brown in cytoplasm of epidermis and lamina propria,Which was the positive expression of MMP-2,TIMP-2 in RAU tissues.The expression of MMP-2,TIMP-2 in ulcer groups were significantly higher than those in controls (P＜0.05),and the expression of MMP-2 in MjAu was significantly higher than those in MIAu and HU(P＜0.05),but no significant difference was found between MIAu and HU groups(P＞0.05);there were no significant difference among the three groups about TIMP-2(P＞0.05).2.RT-PCRThe expression of MMP-2mRNA and TIMP-2mRNA were detected with different intensity in every group.The expression of MMP-2,TIMP-2 in ulcer groups were significantly higher than those in controls(P＜0.05),and the expression of MMP-2 in MjAu was significantly higher than those in MIAu and HU(P＜0.05),but no significant difference was found between MIAu and HU groups(P＞0.05);there were no significant difference among the three groups about TIMP-2(P＞0.05).Conclusions1.The expression of MMP-2,TIMP-2mRNA and protein existed in RAU tissues,which were obviously higher than the normal mucosa.2.The expression of MMP-2,TIMP-2mRNA and protein in MjAu were obviously higher than MIAu and HU.3.The MMP-2 and TIMP-2 were critically involved in the occuring and development of RAU.