Analysis Of The Expression Of MiRNA-21,miRNA-135B And MiRNA-141in Colorectal Carcinoma And Plasma

Objective:To detect the variation of the expression of miRNA-21, miRNA-135b and miRNA-141between colon cancer tissue and surgical margin tissue, investigate the correlation of their expression and evaluate the relations of these microRNAs with tumor differentiation, invasion, lymph node metastasis and Dukes’staging. To establish a method to extract microRNA from plasma, and analysis the expression level of miRNA-21, miRNA-135b and miRNA-141in plasma of colon cancer patients and healthy controls.Methods:The expression level of miRNA-21, miRNA-135b and miRNA-141were determined by using fluorescent real-time quantitative PCR in40cases of colon cancer tissue and surgical margin tissue. The relationship between the expression level of these genes and the pathological data were analyzed. The expression level of miRNA-21, miRNA-135b and miRNA-141in plasma were also detected by using fluorescent real-time quantitative PCR and were analyzed.Results:The expression of miRNA-21, miRNA-135b and miRNA-141in colon cancer tissue were (8.49±4.21),(0.097±0.041) and (0.186±0.072), while in surgical margin tissue were (4.02±2.13),(0.011±0.007) and (0.031±0.017), the expression of these genes were higher in colon cancer tissue than that of surgical margin tissue(P<0.05). The expression level of miRNA-21, miRNA-135b and miRNA-141has no correlation with age, sex, and pathological type of tumor in colon cancer tissue. The expression level of miRNA-21has correlation with lymph node metastasis(P<0.05). The expression level of miRNA-135b has correlation with lymph node metastasis and Dukes’staging (P<0.05). The expression level of miRNA-141has correlation with invasion, lymph node metastasis and Dukes’staging (P<0.05). The expression of miRNA-21, miRNA-135b and miRNA-141in the plasma of colon cancer patients were (0.106±0.082),(0.037±0.052) and (0.068±0.065), while in the normal control group were (0.041±0.057),(0.009±0.013)and (0.011±0.010), the expression of these genes were higher in the plasma of colon cancer patients than that of normal control groups (P<0.05). The expression level of miRNA21in plasma of colon cancer patients doesn’t correspond with that in colon cancer tissue while both of miRNA135b and miRNA-141have positive correlation.Conclusions:The higher expression of miRNA-21, miRNA-135b and miRNA-141in colon cancer tissues indicate that these microRNAs play important roles in the process of tumorigenesis. The relevance of these genes with tumor differentiation, lymph node metastasis and Dukes’ staging age prompts that miRNA-21, miRNA-135b and miRNA-141may be indicators to the degree of malignancy of colon cancer and lymph node metastasis and has good pathoclinical diagnostic value. The variation of expression level of miRNA-21, miRNA-135b and miRNA-141in plasma indicates that these genes could play as potential tumor markers. Targeting these genes may be a new approach to treat colon cancer.