Significance of Irisin (FNDC5) Expression in Colorectal Cancer

Abstract

Background/Aim: The role of irisin, the extracellular part of fibronectin type III domain containing 5 (FNDC5), in colorectal cancer (CRC) is unclear. The aim of this study was to investigate immunohistochemical (IHC) expression level of irisin and correlations with clinicopathological factors in patients with CRC. Materials and Methods: We collected 222 archived CRC samples and 26 control samples from autopsies conducted at the Department of Forensic Medicine. They were used to perform IHC reactions detecting irisin, Ki-67, minichromosome maintenance protein complex component 3 (MCM3), and urine diphosphate-galactose ceramide galactosyltransferase (UGT3) expression. The correlations with Ki-67, MCM3, and UGT3 were analyzed. Irisin expression was also evaluated in cancer cell lines by immunofluorescence reaction and western blot. Results: Irisin expression was higher in cancer cells compared to the control tissues (p<0.0001). Irisin expression was significantly higher in stage I than in stage III (p=0.013) and IV CRC (p=0.05). Conclusion: The correlation between higher expression of irisin and cancer stages indicates its potential usefulness as a marker in CRC.