| ObjectiveTumerigenesis and tumor development is a multiple - stage progress based on change of many genes. Activation of oncogene and in-activation of tumor suppress gene lead to onset of tumor through their influences on signal pathway, cell cycle and apoptosis. In normal situation, cellular signal transduction is a highly organized process. Recent research found that Caveolae, the vesicular imaginations of the plasma membrane, play important role in lipid metabolism and signal transduction.Caveolin, a 21 - 24kD integral membrane protein, is a major component of Caveolae. The Caveolin gene family has now been shown to include 3 members; caveolin - 1, caveolin - 2 and caveolin - 3. caveolin - 1 and caveolin - 2 are expressed in vascular endothelium, adipose cells, smoothe muscle cells and fibroblasts, however, caveolin - 3 is expressed in myocardial cell and skeletal muscles.In date, there were many researches that focus on the functions of caveolin -1 on tumorigenesis and tumor development. But the results were disputed. There was no report on caveolin -1 expression and its significance in NSCLC tissue. In our study, we investigated the expression of caveolin - 1 in 60 NSCLC cases immunohistochemically and analyzed its association with clinicopathological factors and overall survival.Material and methods1. cases60 NSCLC cases with neighboring noncancerous tissue samples were obtained from patients who had received surgery in the Anshan Tumor Hospital between 1980 and 2001, fixed in 4% paraformalde-hyde, embedded in paraffin. Follow - up were available to all cases.2. Main agentsPrimary antibody, mice anti human and - caveolin -1 polyclonalantibody was donated by Doctor Liu Jun ( The Albert Einstein CancerCenter, Albert Einstein College of Medicine). The Ultra - sensitive S- P kit and DAB agent kit were bought from Fuzhou Maxin BiologicalCompany.3. Methods3.1 Immunohistochemistry for caveolin -1We detected the caveolin -1 expression by immunohistochemistry S - P method. Evaluation of result; Brown granules existing in plasma and membrane mean positive expression, caveolin - 1 was expressed in nonnal bronchial mucosal epithelium and type I alveolar cell; vascular endothelium was positive expression, as internal positive control. According to the ratio of positive cells, immunoreactivity was scored as follows: ^90% expression decrease, >90% normal expression.3.2 assay of MVD, ( microvascular density) :Microvessel density was determined by immunohistochemistry for caveolin - 1, because it was expressed in vascular endothelium. After the areas of highest vas-cularization had been chosen under low power, vessel count within tumors was carried out in 3 fields at 200 magnification. The averagecounts of the 3 fields were recorded, and the mean value of the 2 investigators was used for the MVD.4. StatisticsAll statistical calculations were carried out using the Statistical Product and Services Solutions (SPSS) statistical software. The Chi -square test and Student t - test were used to analyze data. Multivariate analysis was analyzed by Cox model. The cut - off for statistical significance was defined as P <0.05.ResultsIn NSCLC, positive expression rate of caveolin - 1 was 50%. Positive expression rates of caveolin - 1 in squamous cell carcinoma and adenocarcinoma were 50%. There was no apparent difference between the expression level of adenocarcinoma and squamous cell carcinoma. There was no significant difference in caveolin - 1 expression between NSCLC in stage I and II and NSCLC in stage HI and IV, with the positive expression rate of 66. 7% and 45. 8% respectively ( P > 0.05). However, there was significant difference in caveolin -1 expression between well - differentiated and poorly differentiated NSCLC. In well differentiated cells the abnormal expression rate was 78. 6% , much higher than 41. 3% of poorly and moderately differentiated NSCLC ( P = 0. 003 ). caveolin - 1 expressed in 37. 5% cases with lymph node metastasis and in 75% cases without...
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