Expression Of CEACAM1 In Serum And Tissues Of Patients With Gastric Cancer And Its Clinical Significance

Objective: To investigate the relationship between the expression level of carcinoembryonic antigen-associated cell adhesion molecule 1(CEACAM1)and clinicopathological characteristics in gastric tissues,we detected the expression level of CEACAM1 in peripheral blood and tumor tissues of patients with gastric cancer and healthy controls,and analyzed the diagnostic value of serum CEACAM1 in gastric cancer,combined with clinically used serum tumor markers.Methods: 1.Preoperative fasting peripheral blood was collected from 98 gastric cancer patients who had been diagnosed by pathological diagnosis before general surgery and underwent D2 radical surgery at the 94 th Hospital of the People's Liberation Army Joint Service and Support Force from September 1,2018 to November 30,2019,and collected peripheral blood of healthy people as control group.The serum CEACAM1 expression level was detected by ELISA,and we analyzed and compared the expression differences between the two groups.We evaluated the diagnostic value according to the ROC curve,and compared it with the ROC curve of serum tumor markers CEA CA125 CA199 and CA724 commonly used in gastric cancer to evaluate its diagnostic efficiency.2.We collected postoperative cancer tissues and paired adjacent cancer tissues of gastric cancer patients at the same time,and detected the expression level of CEACAM1 in the two groups by immunohistochemistry(S-P)to understand the difference between cancer tissues and adjacent tissues.To further compare the relationship between the expression level and the expression patterns of CEACAM1 in gastric cancer tissues and the clinicopathological data.Results: 1.The median serum CEACAM1 was 1262.28 pg/ml [(1054.12,1614.81)pg/ml]in gastric cancer group and it was 815.67 pg/ml [(626.82,1029.47)pg/ml] in normal group.Compared with the normal control group,the serum CEACAM1 level in the gastric cancer group was significantly increased,and the difference was statistically significant(P<0.001).2.The area under the ROC curve(AUC)of serum CEACAM1 is 0.843,and the highest point of the Youden index is 1095.21 pg/ml as the cutoff value.At this time,the sensitivity of CEACAM1 in the detection of gastric cancer was 71.43% and the specificity was 85.71%.It was also calculated that the AUC of CEA CA125,CA724 and CA199 was 0.721,0.626,0.694,0.586,the sensitivity was 60.20%,69.39%,62.24%,67.35%,and the specificity was 77.14%,54.29%,74.29%,and 51.43%,both lower than the sensitivity and specificity of CEACAM1.Therefore,the diagnostic value of CEACAM1 is significantly higher than the four tumor markers mentioned above.3.The results of immunohistochemistry showed that 98 cases(100%)of CEACAM1 were positive in gastric cancer group,among which 21 cases(21.43%),49 cases(50%)and 28cases(28.57%)were positive in membrane expression,Cytoplasmic expression and mixed expression respectively.However,the number of CEACAM1 positive in adjacent tissues was only 10(10.20%)with low expression,of which 5 were membrane-expressed,1 was cytoplasmic expression,and 4 were mixed expression in cell membrane and cytoplasm.The expression level of CEACAM1 in gastric cancer tissues was significantly higher than that in adjacent tissues,and the difference was statistically significant(P<0.001).There were differences in the three expression patterns of CEACAM1 in gastric cancer tissues and adjacent tissues,which were statistically significant(P<0.05).4.The expression level of CEACAM1 in gastric cancer was significantly correlated with invasion depth,lymph node metastasis,tumor differentiation and clinical stage,(P< 0.05),but it wasn't with gender,age,tumor size,tumor location and vascular tumor embolus(P> 0.05).5.The expression pattern of CEACAM1(membrane expression,cytoplasmic expression,mixed expression)was closely related to the degree of gastric cancer differentiation and clinical stage(P<0.001).Conclusion: 1.The expression level of CEACAM1 in gastric cancer patients was significantly higher than that in healthy people.Compared with CEA,CA125,CA724 and CA199,serum CEACAM1 has larger area under ROC curve,higher sensitivity and specificity,and is of better diagnostic value for gastric cancer,which can be used as an diagnostic index for gastric cancer.2.The expression of CEACAM1 in gastric cancer was significantly higher than that in adjacent tissues,suggesting that CEACAM1 may play a role in the carcinogenesis of gastric cancer.High CEACAM1 expression is associated with malignant biological behavior of gastric cancer.3.The cytoplasmic expression of CEACAM1 was significantly higher than that of cell membrane in gastric cancer with poor differentiation and later clinical staging,suggesting that the cytoplasmic expression of CEACAM1 was involved in the progression of gastric cancer,and its different expression patterns were helpful to the prognosis of gastric cancer.