Expressions Of EGFR,c-Met And Ki-67 In Gastric Cancer And Their Clinical Pathological Significance

Gastric cancer, a kind of malignant tumor that originates from gastric epithelial tissues, is one of the most commonly seen human malignant tumors. According to the statistics in 2011, the morbidity and mortality of gastric cancer ranked the second and third place among malignant tumors, respectively, indicating that gastric cancer was a disease that severely impaired human health. With the continuous development of diagnosis and treatment measures currently, the prognosis of early gastric cancer is greatly improved, however, that of advanced gastric cancer remains poor, with low 5-year survival rate(about 15%). As the prognosis for patients with progressive gastric cancer is poor, it is of great importance to seek effective molecular markers for prediction and prognosis. TNM staging is an important factor that determines gastric cancer prognosis, however, research by multiple domestic and overseas institutions discover that there are different prognoses even for gastric cancer patients with the same TNM staging, the mechanism of which may be related to several factors.c-MET and EGFR are the receptor tyrosine kinases(RTKs) in the surface of gastric cancer cells. It is verified in previous research that there are cross sites among the signal pathways mediated by c-MET and EGFR. Previous research indicate that c-MET and EGFR in tumor cells play a mutual complementary role in activating the Akt signal pathway. Ki-67, an important index to evaluate the proliferation activity of tumor cells, is of great significance to the judgment of gastric cancer prognosis.The research comparatively observe the expressions of EGFR, c-Met and Ki-67 in gastric caner patients with 1-year and 3-year survival, and analyze the expressions of EGFR, c-Met and Ki-67 in gastric caner as well as the clinical pathological parameters, including the relations with sex, age, and with/without vascular invasion with an aim to further explore the expressions of EGFR, c-Met and Ki-67 in gastric cancer patients with the same TNM staging and to analyze their values for the survival and prognosis of patients with gastric cancer. Hopefully, the results in the research can offer a certain explanation and some theoretical support for different prognoses for gastric cancer patients with the same TNM staging.Objective: Detect the expressions of EGFR, c-Met and Ki-67 in gastric cancer and normal gastric mucosa by immunohistochemical staining method(SP method), detect the expression of the above-mentioned indexes in cases of 1-year and 3-year survival but of same TNM staging, respectively, and discuss the expressions of EGFR, c-Met and Ki-67 in gastric cancer as well as the clinical pathological and prognostic significance.Methods: 88 gastric cancer cases that received surgical resection recorded from October, 2010 to July, 2012 with complete clinical and follow-up information were collected from the pathology department of Chengde Central hospital. The Lauren typing of all cases was intestinal type, and the staging was T2N1M0. There were 36 cases of 1-year survival postoperatively, 52 of 3-year survival, and additional 46 cases of normal gastric mucosa were collected. Reviewed and studied all slices of the cases, and chose paraffin blocks with typical lesions but without obvious hemorrhagic necrotic tissues for immunohistochemical detection.Marked the expressions of EGFR, c-Met and Ki-67 in gastric cancer with immunohistochemical method(S-P method), applied chi-square test to the enumeration data of research results, and adopted spearman rank correlation for correlation analysis, with P<0.05 as statistically significance.Results:1 The positive expression rates of EGFR, c-Met and Ki-67 in gastric cancer tissue are 86.1%, 82.4% and 94.3% respectively, which are all obviously higher than normal gastric mucosa tissue(19.8%, 18.3%, and 21.4%, P<0.05).2 In gastric cancer tissue with vessel invasion, the strong positive expression rates of EGFR, c-Met and Ki-67 are all higher than those in gastric cancer tissue without vascular invasion(82.1% vs 10.2%, 92.3% vs 16.3%, 94.8% vs 18.4%, P<0.05).3 The expressions of EGFR, c-Met and Ki-67 in gastric cancer tissue are closely related to the post operation survival time. The strong positive expression rates of EGFR, c-Met and Ki-67 in gastric cancer tissue with 1 year's survival time are separately 77.8%, 91.7% and 94.4%, which are obviously higher than those of 3 years' survival time group(17.3%, 21.2% and 23.1%, P<0.05).4 The expression of EGFR, c-Met and Ki-67 in gastric cancer were not related to age or sex(P>0.05).5 Statistics analysis indicated that the all the expression of EGFR and c-Met, EGFR and Ki-67, and c-Met and Ki-67 in gastric cancer showed positive correlation, with(EGFR and c-Met;r=0.463,P<0.05),(EGFR and Ki-67; r=0.524, P<0.05), and(c-Met and Ki-67; r=0.429,P<0.05), respectively.Conclusions:1 Compared with normal gastric mucosa, the expressions of EGFR, c-Met and Ki-67 in gastric cancer tissue all increase obviously, showing the over-expressions of EGFR, c-Met and Ki-67 are related to the occurrence of gastric cancer.2 The expressions of EGFR, c-Met and Ki-67 are closely related to vascular invasion and prognosis. High expressions of EGFR, c-Met and Ki-67 are symbols of bad prognosis of gastric cancer.3 The expressions of EGFR, c-Met and Ki-67 in gastric cancer tissue are in obvious positive correlation, which shows these three elements play a positive cooperative function during the development of gastric cancer.