A Preliminary Study Of The Endothelial Lipase Expression In Gastric Carcinoma

Gastric cancer is the most common malignant tumors in the digestive system. Withthe national economic development, improvement of national living standards,especially the change of diet, incidence and mortality of gastric cancer show anupward trend year by year. The number of new gastric cancer patients is up to40million each year in China, accounting for42%of gastric cancer patients in the world,and is the second leading cause of cancer death in China. Development of gastriccancer is a complex, multi-stage, multi-factor synergistic dynamic pathologicalprogression, involving a large number of tumor-associated genes and molecules. Butthere is no domestic study of the endothelial lipase expression in gastric cancerreported. In this study, enzyme-linked immunosorbent assay, dot blot andimmunohistochemistry SP method were used to analyze the expression of endotheliallipase in gastric cancer tissues and urine at protein level. And we studied relationshipbetween the expression of endothelial lipase and gastric cancer, in order to provide atheoretical basis for the early diagnosis and timely treatment of gastric cancer.Results:(1) Urine ELISA results: through detection endothelial lipase content inthe urine of gastric cancer and healthy people by ELISA, we found that there was asignificant difference (P <0.05) between the content of endothelial lipase in gastriccancer patients and healthy people. We can infer from95%CI analysis that the ELlevels in urine of healthy people were higher than that in the urine of gastric cancerpatients. Calculating the area under the curve (AUC) by ROC to determine theexperimental accuracy and the efficiency of diagnosis, we learned that the AUC=0.8168, the result has a certain accuracy. Thus, the ELISA method for detection ofEL in the urine of healthy people and gastric cancer patients has a certain diagnosticsignificance. (2) Urine Dot blot results: six pairs urine samples from healthy people and gastriccancer patients were collected randomly for Dot blot analysis. We apply the gelimaging system to analyze the signal intensity. The results showed that P<0.05, therewas a significant difference between EL expression levels in the urine of gastriccancer patients and healthy people, EL showed lower levels in the urine of gastriccancer patients.(3) Results of ELISA and Dot blot in blood samples: twenty pairs blood samplesfrom healthy people and patients with gastric cancer were determined by ELISA andDot blot detection. The results showed that: EL protein content can be detected in theserum of health people and gastric cancer patients, but there was no significantdifference (P>0.05) between the two groups.(4) Results of immunohistochemical staining: in normal tissue most EL positiveparticles located in the cell membrane, while small amount were founded in thecytoplasm; in tumor tissue the majority of the positive particles located in the cellmembrane, showing the brown particles. There was no significant difference (P>0.05)between normal tissue and gastric cancer tissue on the expression of EL.Conclusion: ELISA and Dot blot analysis showed that the expression ofendothelial lipase in the urine of gastric cancer patients was lower compared withhealthy people. There was no EL expression difference between gastric cancerpatients and healthy people in the blood. Immunohistochemical staining resultsshowed no significant difference in the level of endothelial lipase expression betweennormal tissue and gastric cancer tissue. Thus, EL may be a potential urine Bio-Markerfor early detection of gastric cancer, and may provide some reference basis for theearly diagnosis and timely treatment of gastric cancer.