Comparative analysis of tumor control gene and microRNA expression profiles in tumor and adjacent tissues in patients with colorectal cancer

Abstract

Background. Various tumor control genes and microRNAs (miRNa) play an important role in the development and progression of colorectal cancer (CRC). the expression of these genes can differ significantly in tumor and adjacent healthy tissues. there is no exact data at what distance from the tumor the adjacent healthy tissue is located in terms of gene expression.The aim of the investigation was to study the tumor control genes (E2F3, TGFB, NFKB, KLF-12, EGFR and MMP9), as well as the microRNA genes (microRNA-15, -16, -21 and -210) expression profiles in tumor and adjacent healthy tissues.Material and methods. the study included 19 patients diagnosed with colorectal cancer. the tumor control genes (E2F3, TGFB, NFKB, KLF-12, EGFR and MMP9), as well as the miRNA genes (miRNA-15, -16, -21 and -210) expression levels were investigated in tumor and adjacent normal tissue samples taken during colonoscopy.Results. a decrease in the level of expression of E2F3 (median 3,73, Q1-Q3 2,64 Reu vs. median 6.5, Q1-Q3 6,39 REU, p=0,01) and miRNA-16 (median 2,83, Q1-Q3 4,74 REU vs. median 4,29, Q1-Q3 3,73 REU, p=0,027) and an increase in the expression level of miRNA-21 (median 2,64, Q1-Q3 1,38 REU vs. median 1,41, Q1-Q3 1,21 REU, p<0,001) were found in tumor tissue compared to normal tissue of patients with CRC.Conclusion. significant differences in the E2F3, miRNA-16 and miRNA-21 gene expressions were revealed. an increased level of E2F3 and miRNA-16 expressions at a distance of 1–2 cm from the tumor may be a predictor of tumor recurrence and progression, and an increased miRNA-21 expression in tumor tissue as compared to adjacent tissue may be a negative prognostic factor. this information can be used in further clinical research.