The Significance And Expression Of CD₄₄V₆,MMP-9 In Brain Metastases And Malignant Glioma Invasion

The most familiar malignant tumors in human central nervous systerm are glioma and brain metastases. They have taken many clinical diffecults and became the main reason of patients' dead.It have been reported that invasion and meatstasis of the malignant tumor take three -steps mechanisms: tumor cell attachment to host cellular or extracellular matrix determinants; tumor cell proteolysis of host barriers such as the basement membrane, tumor cell locomotion and tumor cell colony formation in the target organ for metastases. ,A number of studies have showed that cellular adhesion moleculer CD44 variant exon 6 is associated with the creation and development of the human malignant tumors. And the important role of Matrix metalloproteinases in the invasion and metastasis of malignant tumors has been know.Materials and methodsThe purposes of this study was to determine the expression of CD44Vg6 MMP-9 in human brain tumors by immunohistorchemistry in order to determine their roles in the process of invasion and metastasis.1. clinical dataChoose and use 90 case samples from the neurosurgery department of the chinese medicine university attached first hospital from 2000 March to 2003 December , the sample of pathology confirmed after surgical operation; 25 cases brain metastases ; 30 cases glioma ; 25 cases positive brain tumor and 10 cases normal brain tissue which selected from intercerelal lesion operation .2. Immunological ReagentsThe mouse anti-human CD44V6 and MMP-9 monoclonal antibody were purchased from the Beijing zhongshan biotechnology company. The S-P method was used in immunological staining and the S-P reagent was purchased Beijing zhongshan biotechnology company. Positive samples was used for comparision and negative samples for PBS.3. Dye method is the convertional S-P method.4. Judge the consequentionObserve the cell membrane and plasma under 200 time mircroscopes, and count 5 high time visual fields, positive cell is yellow staining in the cell membrane or plasma. Positive cell number <5% for the " - ".; positive cell number 5 -50% for the " + " ; positive cell number > 50% for " ++ ".5. Statistical analysisAdopt the SPSS. 10 software to proceed the x2-test and relativity analysis.ResultsMMP-9 isnot obviously showed in normal brain tissuse,the positive ratio of MMP-9 is 24% in positive brain tumor tissues,but its positive ratio are 86.67% and 88% respectively in glimoa and brain metastases. There isnot significant difference at the positive ratio in glioma and brain metastases (P >0. 05). But they have significant difference to compare with normal brain tissue and positive brain tumors( P < 0.01).CD44Vg expressed only in brain metastases ,its positive ratio is 52%. CD44 V6 did not express in normal brain tissue positive brain tumor and glioma . There is the obvious difference in statistics analysis.DiscussionThe invasion and metastases of the malignant tumor is the result for home cell and tumor cells' complicated interaction . But adhesion is the first step . The adhesion moleculoer CD44 extensively exist the celluar membrane , which is akind sugar-protein . It can connect with HA in extracellular matrix ( ECM) , and be involved in various aspects of cell-cell and cell-matrix adhesion . A number of studies have been reported that the CD44 variant exon 6 has been expressed on the surface of malignant celluar membrane.Li H et al have reported that variant CD44 adhesion moleculers are expressed in human brain metastases but not in glioblastams . This showed that CD44 V6 was associated with the procession of malignant tumor's metastases . We have taken the similar result . So we consider that CD44V6 has the function of lymphocyte homing and recirculation . CD44 appears to function as the principal cell surface receptor for hyaluronats . CD44V6 expression on the plasma membrane of papillary carcinoma cells contributes to the ability of these cells to me-tastasize to regional lymph nodes and then to remain there . CD44 is also implicated as a ce...