Differential Expression of Mirnas in Colorectal Cancer.

Abstract

Colorectal Cancer (CRC) is one of the deadliest diseases in the world and current screening methods are still limited. In past decade, it has been discovered that miRNAs play an important role in every cell process including CRC initiation and progression. The aim of this study was to identify differentially expressed miRNAs in normal colon (CRN) and Colorectal Cancer (CRC) by using microarray system. This includes discovery of new miRNAs related to CRC. Total RNA was extracted from total 12 tissue samples of 7 patients with colorectal cancer undergoing surgical resection of the colon for studying tumor specific changes in miRNA expression compared to 5 matched as normal tissue samples using the Qiagen miRN easy Kit. MiRNA was polyadenylated by using PolyA Tailing master mix. After Flash Tag Biotin HSR Ligation samples were hybridized, stained and washed. The arrays were finally scanned using AGCC Scan control programmer according to the manufacturer's protocol of Affymetrix Gene Chip software. It was found that some of miRNAs were found up or down regulated in studied CRC tissues compared to non-tumor tissues. MiR-1201, miR-181a, miR-7, miR-188, miR-552, miR-183, miR-941, U71d, ACA3-2 and miR-34c were over expressed and miR-486, HBII-85-6, miR-550-1, miR-635, miR-10b, miR-550-2, ENSG00000238430 and miR-548a were down regulated in patients with CRC. We have also found that some dysregulated miRNAs, which to our knowledge have not previously been associated with colorectal carcinogenesis. Consequently, the results of this study will increase our understanding of development, progression and earlier detection and personnel treatment of colon cancer. This work was supported by grants from the Turkish Ministry of Development (2009K120780 and 2012K120690).

An miRNA Signature Predicts Grading of Pancreatic Neuroendocrine Neoplasms

“…MiR-9-5p up-regulation in breast cancer has been shown to affect FOXO1, LIFR, and E-Cadherin expression, inducing resistance to therapy with alkylating agents (43,44) and tamoxifen (43)(44)(45) and consequently increasing metastatic potential and negatively affecting patient outcomes. miR-9-5p up-regulation also correlates with increased metastatic potential and tumour recurrence of head and neck cancer (45,46). miR548d-5p.…”

Role of Exosomes and Exosomal microRNAs in Cancer

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