Expression Of EIF2α And Its Relationship With K-RAS Gene Mutation In Colorectal Adenocarcinoma

Objective To detect the expression of eukaryotic translation initiation factor 2α(eIF2α)in colorectal adenocarcinoma and the relationship with the mutation of Kirsten rat sarcoma viral oncogene(K-RAS),so that reveal the impact of eIF2α expression on prognosis,providing reference data for the experiments investigating the principle of colorectal adenocarcinoma occurrence and development.Methods Sixty-four specimens of colorectal adenocarcinoma were selected from January2016 to December 2017 in the Affiliated Hospital of North China University of Science and Technology as the study subjects.The corresponding normal colorectal mucosa tissues which were 5 cm away from the edge of the tumour were collected as controls.All of the tissues were embedded with paraffin.The expression of eIF2α was detected by immunohistochemical EnVision method.Twenty-two fresh specimens of colorectal adenocarcinoma and adjacent colorectal mucosa as the above specimens were selected,and semi-quantitative expression of eIF2α was measured by Western Blot.The K-RAS gene mutations in 32 tumour tissues were detected by Real-Time Fluorescent Quantitative PCR.The survival time of the patients after surgery was recorded.Results 1 Immunohistochemistry results showed that the positive rate of eIF2αexpression in colorectal adenocarcinoma tissues was 56.4%(36/64),which was higher than that in normal colorectal mucosa tissues 21.9%(14/64).The results were statistically significant(P<0.001).The positive expression of eIF2α was associated with the depth of invasion and existence of cancer nodules(P<0.05),and was not related to gender,age,maximum diameter of tumour,tumour differentiation,lymph node metastasis,tumour location or the existence of cancerous node.2 Western Blot results showed that the relative expression of eIF2α in colorectal adenocarcinoma was significantly higher than that in the adjacent colorectal mucosa(P<0.001).3 According to the Real-Time PCR results,18 tumour tissues showed K-RAS genes mutation,whereas the other 14 tissues expressed only wild-type K-RAS genes.In the 18 tissues showed K-RAS gene mutation,there were16 cases(88.9%)showing eIF2α immunohistochemical positive expression;while in the14 cases with wild-type K-RAS genes,only 8 cases(57.1%)showed eIF2αimmunohistochemical positive expression.There was a positive correlation between the KRAS mutation and eIF2α expression by using Spearman correlation analysis(r=0.364,P=0.041).4 Kaplan-Meier survival analysis and single-factor,multi-factor Cox regression analysis did not find any correlation between eIF2α expression and patient survival time.Conclusions 1 eIF2α was highly expressed in colorectal adenocarcinoma and was associated with tumour invasion depth and the existence of cancerous node.2 The expression of eIF2α in colorectal adenocarcinoma has a weak positive correlation with KRAS gene mutation.3 The expression of eIF2α in colorectal adenocarcinoma was not related to prognosis.Figure6,Table7,Reference 57...