| ObjectiveE - cadherin/β - catenin ( E - cd/Cat) complex play an important role in tumor metastasis and invasion, β - beta plays critical roles both in intercellular adhesion and in the Wnt signaling pathway. When localized in the membrane, β - catenin acts as a cadherin - interacting protein by linking cadherin to a - catenin and, hence, mediating anchorage of the cadherin complex to the cortical actin cytoskeleton. In addition, the WNT signaling can stabilize β - catenin and cause it to accumulate in the cytoplasm and nucleus where it can act as a tran-scriptional coactivator by associating with the TCF/LEF family of transcription factors. Because of its important function in tumor metastasis and carcinogenesis, in this study, we evaluate the immunohistochemi-cal expression status of β - catenin and E - cadherin in hepatocellular carcinoma, study relationships of expression of β - catenin and E -cadherin with hepatocellular carcinoma, associated clinical and pathological parameters.Material and Method1. Specimen:We got 72 archival formalin - fixed, paraffin - embedded surgically resected cases of HCC from China Medical University second affiliated hospital during 1994 -2001. Every specimen has nontumorousliver tissue according to the result of the HE stain. Another 20 specimens of cirrhosis are chosen to be the control together with nontumor-ous liver tissues. Three 4 - um serial sections were obtained from each paraffin block: one for HE stain, the other for immunohistochemistry stain.2. Reagent and methodDetect the β - cat and E - cd expression by S - P method of immunohistochemistry. Anti - β - cat primary antibody was from Trans-duction company in USA , anti - E - cd primary antibody was from MaiXin company in China. The immunohistochemistry reagent box was from MaiXin company. The concentration of anti - β - cat antibody is 1:800.The stain of nontumorous liver cell served as positive control. PBS, instead of primary antibody, acted as negative control. Two sections were chosen to stain each HCC specimen. After deparafGnization and rehydration, immerse the sections for 20 minute in absolute meth-anol containing of 3% H2O2, then unmask antigens, incubation after calf serum treatment, primary antibodys ( β - cat and E - cd) were respectively treated to the sections and at 4℃ overnight. Secondary antibodies(1 ;100) treatment , incubate 20 minutes ,stain by DAB, water wash. The sections were counterstained with hematoxylin, dehydrated in graded ethanol, clear inxylene and mounted.3. Standard of Observed ResultsThe positive stained part shows brown. Five randomly chosen visual field were observed on each section under microscope. The proportion of positive stained cells was calculated among 100 tumor cell. According to standard of Maruyama et al, our judgment of β - cat obeyed under rule; more than 70% tumor cell' s membranes staining positiveis normal express, reverse is absence of membrane expression. More than 10% cytoplasm or nuclei staining positive of tumor cells is abnormal located expression, β - cat' s abnormal expression includes absence of membrane expression and abnormal located expression. E -cd expression: more than 70% tumor cell get the positive stain of membrane is normal expression, reverse to that is abnormal express.Chi - squared test was applied to analyze the result of experiment by SPSS 10.0 which is a statistical software package. P <0.05 represent marked statistical significance.Results1. Expression of β - cat and E - cd in different tissues Expressions of E - cd and β - cat iii nontumorous liver cell andcirrhosis are mostly located on cell membrane , not in cytoplasm or nuclei, there is no statistic significance between Paratumor and cirrhosis. Abnormal expressions of E - cd shows decrease or absence stain on membrane in tumor cells. Abnormal expression of p - cat shows decrease or absence stain on membrane or positive stain in cytoplasm or nucleus. Tumor group VS paratumor group; PECD =0.001, PCAT < 0.001. Tu...
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