| Objective and Background DataGastric cancer is one,of the most common malignancy in adults, which is the leading cause of cancer death worldwide. Many factors correlated with the carcinogenesis of gastric cancers, however, the definite etiologic cause was still not well known. Recently, some authors reported that apoptosis was closely related to the pathogenesis of tumors, alteration of apoptosis was essential for cancer development. Several factors such as Caspase - 3, Bcl - XLand Cox - 2 were attached importance to the apoptosis. Caspases - 3 play an essential role during apoptotic cell death. Caspase - 3 is considered to be the main effector Caspase as the final executioner involved in both physiologic and pathologic course of cell death. Bcl - XL was found as a member of the Bcl - 2 family, a group of apoptosis regulating genes which can inhibit or promote apoptosis. It was reported that Bcl - XL was able to inhibit the activity of Caspase - 3, which leads to an inhibition of apoptosis. Moreover, high expression of Cox - 2 in cancer tissues might play an antagonism role for apoptosis inducted by promoters , which led to increase of Bcl - 2 proteins expression. Because Caspase - 3, Bcl - XL and Cox - 2 play an important role in apoptosis, analysis of the expression status of them is necessary to predict apoptosis alterations of tumor cells in vivo. To date, there have been studies demonstrating expression of them in human cancer tissues, but not specifically in gastric cancer. The relationship between these three factors in gastric cancer progression has not been sufficiently investigated, and their influence on the biological properties and the prognosis of gastric cancers remains unknown. The purpose of the present study was to ana-lyze the expression of Caspase - 3, Bcl - XL and Cox - 2 in a series of gastric cancer tissues by immunohistochemistry and to evaluate the clinicopathological relevance of these three factors.MethodsPatients and Tissue SamplesThe present study investigated the gastric cancers of 54 patients who underwent gastrectomy with lymph node dissection at the Department of Surgery, the Second Hospital affiliated to China Medical University, between 2000 and 2003. Surgically resected specimens embedded in paraffin were examined.Agents and instrumentsThe monoclonal antibody against Caspase - 3, Bcl - XL as well as Cox - 2 (zhongshan Co. , Beijing) were used, immunohistochemistry box S -ABC was purchased from Boside, Wuhan. The series of instruments for immunohistochemistry were provided by the Department of Pathology, the Second Hospital affiliated to China Medical University.Immunohistochemical stainingFrom every archival paraffin block, the tissue was taken from representative areas and sections of the resulting tumor tissue were 4|xm in thickness. According to the directions of S - ABC agents, immunohistochemical staining was performed stepwise. The monoclonal antibody against Caspase - 3, Bcl - XL and Cox -2 were diluted byl :200, 1 :.100, 1:50 respectively.Immunostaining observation5 incontinuous microscopical fields were observed, and the brown - yellow granules present in cytoplasma represented the positive result. The intensity of the immunostaining with all the antibodies was evaluated by dividing the staining reaction in four groups: - , negative; + , positive.Statistical analysisSPSS11.5 for windows was used for statistical analysis. The significance of the associations between Caspase - 3, Bcl - XL, Cox - 2 and clinical pathological behaviors was determined using X2 test and correlation analysis. Probabilityvalues p < 0.05 were considered statistically significant.ResultsPositive cytoplasmic immimoreactivity was seen in a proportion of 22. 2% for Caspase -3, 53.7% for Bcl - XL, and 62.9% for Cox -2 in the samples of gastric cancer analyzed respectively. There was a significant correlation between expression of Caspase - 3 and Bcl - XL ( r = - 0. 308, P = 0. 024 ) , as well as between Bcl - XLand Cox - 2 ( r = 0.442, P = 0...
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