Protein Expression Of EGFR,Ras And CEA In Esophageal Cancer, Gastric Cancer And Colorectal Cancer

Background and Objective:Digestive carcinoma, especially esopha-geal cancer, gastric cancer and colorectal cancer, is most common in our country. Many factors and genes are related to their carcinogenesis. As carcinomas in alimentary canal, esophageal cancer, gastric cancer and colorectal cancer are all influenced by similar factors such as diet, habits and customs, environment and hereditary predisposition. On the other hand, these three carcinomas lie in different locations in alimentary canal, with different anatomical structure and different physiological function.This fact determins that these risk factors have distinctions in kind and character. In recent years, EGFR(epidermal growth factor receptor), Ras (Proto-oncogene ras) and CEA(carcinoembryonic antigen) protein were paid much attention to carcinomas genesis. Targeted therapy aimed at EGFR and Ras protein has been researched in recent years. By analyzing the expression of EGFR, Ras and CEA protein in esophageal cancer, gastric cancer and colorectal cancer, and their relationship with clinicopathological parameters, this project investigated the different roles of these three proteins in gastrointestinal cancer. By analyzing the different expression of EGFR, Ras and CEA protein in esophageal cancer, gastric cancer and colorectal cancer, this project intend to find targets for targeted therapy.Methods:Surgically resected and pathologically proved cases of esophageal cancer, gastric cancer and colorectal cancer were collected. Information related to patiens'gender, age, tumor location, histological type and pathological stage were recorded. Complete clinical information were obtained in this study. None of these patients received either radiocherapy or chemocherapy before the surgery. The specimen cases were immunostainde to observe the expression of EGFR, Ras and CEA in esophageal cancer, gastric cancer cells and colorectal cancer cells. All the results were statistically analyzed with SPSS 11.5 software package.Results:1.The positive expression rate of EGFR in gastric cancer group was obviously higher than colorectal cancer group(P<0.05). The positive rate of Ras expression in esophageal cancer group and gastric cancer group was obviously higher than colorectal cancer group(P<0.05). The positive rates of CEA expression in esophageal cancer group were obviously lower than colorectal cancer group(P<0.05).2.The relationship between EGFR, Ras and CEA protein expression and clinical characteristics.(1) In esophageal cancer group, the positive expression rate of EGFR, Ras and CEA have no obvious relationship with patiens'gender, age, tumour location, differention degree, depth of invasion and lymph node metastasis (P>0.05).(2)In gastric cancer, the positive rate of EGFR protein expression in poor differentiation group was higher than well-moderate differentiation group(P<0.05); the positive expression rates of Ras in penetrated subserous layer group was higher than infiltrated to subserous layer group(P<0.05); the positive expression rate of CEA in distant metastasis group was higher than without distant metastasis group(P<0.05).(3)In colorectal cancer, the positive rate of EGFR protein expression in infiltrated to subserous layer group was higher than penetrated subserous layer group(P<0.05); the positive rate of Ras protein expression in infiltrated to subserous layer group was higher than penetrated subserous layer group(P<0.05).3.The correlation between EGFR, Ras and CEA protein expression.(1)In esophageal cancer, EGFR protein expression was positively correlated with CEA protein expression(r=0.552, P<0.05). There was no significant correlation between EGFR and Ras expression(P>0.05), and the same as CEA and Ras expression.(2)In gastric cancer, EGFR protein expression was positively corre- lated with CEA protein expression(r=0.457, P<0.05); Ras protein expres-sion is positively correlated with CEA protein expression(r=0.220, P<0.05). There was no significant correlation between EGFR and Ras expression (P>0.05).(3)In colorectal cancer, EGFR protein expression was positively correlation with Ras protein expression(r=0.452, P<0.05). There was no significant correlation between EGFR and Ras expression(P>0.05), and the same as CEA and Ras expression.Conclusions:1.The EGFR, Ras and CEA protein all have expression more or less in esophageal cancer, gastric cancer and colorectal cancer group. These three protein may play a part in carcinogenesis.2.EGFR protein expression in gastric cancer, Ras protein expression in esophageal cancer and CEA protein expression in colorectal cancer were much higher than the other. The protein may be choosed as target for targeted therapy.3.In gastric cancer the expression of EGFR protein has negative correlation to cell differentiation, the expression of Ras protein has positive correlation to depth of invasion, and the expression of CEA protein has positive correlation to distant metastasis.4.EGFR and CEA protein expression has a close relationship in esophageal cancer and gastric cancer. Ras and CEA protein expression has a close relationship in gastric cancer. EGFR and Ras protein expression has a close relationship in colorectal cancer. These three protein may cooperate with each other in carcinogenesis.