DIFFERENTIAL EXPRESSION OF MICRORNAS IN ULCERATIVE COLITIS AND MICROSCOPIC COLITIS AND THEIR RISK OF COLORECTAL CANCER DEVELOPMENT

Abstract: Introduction:Ulcerative colitis (UC) and microscopic colitis (MC) are two different inflammatory bowel disorders. Previous studies claimthatUC patients haveincreased risk for developmentof colorectal cancer(CRC). However, this association has not been detected with MC. Moreover, studies have shownthataltered expression of microRNAs(miRNAs) plays an important role inthe CRC development. Additionally, UC and MC also showed an altered expression of miRNAs.Objective:The aim was to investigate if an altered expression of miRNAs in UC and MC canpartly explain the difference between UC and MC regarding theirrisk of developing CRC. Method:A systematic literature reviewwas performed on priorstudies that investigated the expression of miRNAs in UC, MC and CRC. Studies were obtained from four databases andwere further evaluated, reviewed and compiled with regard to inclusion and exclusion criteria.Result:Multiple studies showed a positive association between altered expression of miRNAs in UC patients and their risk of CRC development. The studies suggested that these altered expressed miRNAs function as potential drivers in thecarcinogenesis. However, the association between altered expression of miRNAs in MC patients regarding their risk to develop CRC remain unclear due to the lack of publications related to this. Conclusion:Due to the lack of publications regarding the association between miRNAs and MC, it remains unclear if miRNAs partly explain UC and MC differences in the risk of developing CRC.