An essential microRNA maturing microprocessor complex component DGCR8 is up-regulated in colorectal carcinomas

Abstract

MicroRNAs (miRNAs) regulate gene expression through degradation and/or translational repression of target mRNAs. Dysregulations in the miRNA machinery may be involved in carcinogenesis of colorectal cancer (CRC). The purpose of the current study was to evaluate the DiGeorge syndrome critical region gene 8 (DGCR8) and argonaute 2 (AGO2) mRNA expression in CRC and to evaluate the value of clinical parameters on their expression. We investigated the mRNA expressions of DGCR8 and AGO2 in 60 CRC tissues and adjacent histologically non-neoplastic tissues by using quantitative real-time PCR. Our study revealed that the mRNA expression level of DGCR8 is up-regulated in CRC. However, AGO2 mRNA expression was not significantly altered in CRC tissues. Neither DGCR8 nor AGO2 mRNA expression level was not associated with any clinical parameters, including age, tumor stage, CEA titer, and BMI in CRC cases. However, the mRNA expression levels of DGCR8 and AGO2 were positively correlated to each other. This study demonstrated for the first time that the DGCR8 mRNA expression level was up-regulated in CRC, suggesting its important role in pathobiology of colorectal carcinogenesis. Keywords MicroRNA biogenesis Colorectal cancer DGCR8 AGO2