To explore the possibility that Arnt might affect this Myc/Miz-1-dependent transcriptional regulation, Arnt was overexpressed in human osteosarcoma U2OS cells together with a luciferase reporter construct containing 35 nucleotides upstream of the transcriptional start site of CDKN2B (−35CDKN2B/luc, [25]). This evidence concerns the gene ARNT and osteosarcoma.