Interferon-induced transmembrane protein 3 (IFITM3) is associated with cancer development. Proto-oncogene c-myc can promote tumor proliferation. However, collections of IFITM3 and c-myc in hepatocellular carcinoma (HCC) and the potential role and mechanisms of IFITM3 in c-myc-mediated tumor proliferation remain unclear. In this study, we investigated a positive correlation between the expression of IFITM3 and c-myc in HCC. The down-regulation of IFITM3 significantly reduced c-myc expression and inhibited the proliferation of HCC in vitro and in vivo. In addition, upregulated c-myc expression restored the decrease in cell proliferation caused by the downregulation of IFITM3, while downregulation of c-myc reduced the proliferation of HCC enhanced by IFITM3. Mechanistically, IFITM3 regulates c-myc expression via the ERK1/2 signalling pathway. In conclusion, a novel path of IFITM3-ERK1/2-c-myc regulatory circuitry was identified, and its dysfunction may lead to HCC tumorigenesis.
Keywords: ERK1/2 signalling pathway; IFITM3; c-myc; hepatocellular carcinoma; proliferation.