AP-1 is composed of dimeric complexes, which included members of four families of DNA-binding proteins such as Jun, Fos, ATF/cyclic AMP-responsive element-binding (CREB), and musculoaponeurotic fibrosarcoma (Maf) (Milde-Langosch, 2005; Hernandez et al., 2008). This evidence concerns the gene FOS and fibrosarcoma.