ARNT and hepatocellular carcinoma: Recently, we demonstrated that an elevated ARNT expression level confers radioresistance in tumour cells (i.e., in Hep3B), which renders the regulation of this transcription factor clinically important.19 Furthermore, other studies revealed a major contribution of ARNT in hepatocellular carcinoma progression25 and point towards ARNT as a potential drug target regarding this malignancy.26