Expression And Significance Of E-Cad And MMP-7 In Gastric Carcinoma

BackgroundMetastasis of gastric carcinoma is the main cause of the therapeutic effect and prognosis, leading to death in tumor patients. Therefore, it is important to research into the mechanism of invasion and metastasis and find out the molecular biomarker for gastric carcinoma metastasis and prognosis, thus presenting novel theoretical basis and clinical value for the effective and rational treatment selection and increasing the survival rate.There are many molecules involving in the invasion and metastasis of gastric carcinoma. Early in 1986, Liotta et. had put forward the three steps theory of cancer cell invasion to extracellular matrix, including of adhesion, degradation and mobility. E-cadherin(epithelia cadherin,E-cad) is the most well-studied member of the cell adhesion molecules, in recent years which is a focus on invasion and metastasis research of cancer cell. In the metastasis of malignant tumor, E-cadherin on the cell membrane is firstly disrupted, leading to mobility and aggressive spread of the cancer cells. Down-regulated expression and abnormal function of E-cadherin maybe involve in the tumorgenesis and progression of early gastric carcinoma. Matrix metalloproteinase (MMP) play an important role in the invasion and metastasis of cancer cells through degrading extracellular matrix proteins. MMP-7 is a crucial member of matrix metalloproteinases family, involved in degrading extracellular matrix and basement membrane. Recently, overexpression of MMP-7 in gastric carcinoma was reported to correlate with progression and poor prognosis.There are many reports that E-cadherin and MMP-7 are correlative with biological characterization of gastric carcinoma. However, reports about combination detection of E-cadherin and MMP-7 expression in gastric carcinoma tissues were rare. Consequently, it will be a helpful attempt to combine the detection of both E-cad and MMP-7 expression in gastric carcinoma tissues and normal gastric tissues, which may be useful to judge to malignant potential of gastric carcinoma.ObjectiveTo detect E-cad and MMP-7 protein expression level in gastric carcinoma tissue and normal gastric tissue, analyze their dependablity with clinical pathological data such as lymph node metastasis, invasion depth, degree of tumorcell differentiation, study the correlation of E-cad and MMP-7 to the occurrence, development and clinical features of gastric carcinoma and the correlation between the expression of E-Cad and MMP-7.MethodsIn this study, immunohistochemical staining (SP method) was used to detect the protein expression of E-cad and MMP-7 in 62 cases of gastric carcinoma and 20 cases of normal tissue (both were archived wax blocks of surgical removal tissue). We also analyze the correlation between them, and explore their clinical significance. All specimens were pathologically confirmed gastric cancer tissue or normal gastric tissue.ResultsE-cad and MMP-7 had different levels of expression in 62 cases of gastric carcinoma tissue: E-cad positive expression rate was 38.7%(24/62), MMP-7 positive rate was 69.4%(43/62).The expression of E-cad was obviously lower than them in 20 cases of normal tissue (75.0%), while MMP-7 was obviously higher than normal tissue (30.0%), the difference had statistically significant (P <0.01). In gastric carcinoma tissues, following with the invasion depth increasing, degradedness of tumor differentiation degree and lymph node metastasis, the positive expression of E-Cad was decreased, and the difference was statistically significant (P <0.05); The positive expression of MMP-7 closely related to invasion depth, tumor differentiation degree and lymph node metastasis ( P <0.05); There existed negatively correlation between the expression of E-Cad and MMP-7 (r=-0.26, P=0.039).ConclusionsThe expression of E-Cad in gastric carcinoma tissues was obviously lower than that in normal gastric tissue, while MMP-7 was obviously higher. The expression of E-cad and MMP-7 played an important role in the biological behavior of gastric carcinoma. The detection of E-Cad and MMP-7 in gastric carcinoma tissue will help to comprehend the malignant biological behavior of gastric carcinoma, and they may serve as effective markers in the judgment for gastric carcinoma prognosis.