TOP3A and osteosarcoma: Within the 17p11 amplified region, previously described to be frequently amplified in osteosarcomas (Forus et al, 1995; Tarkkanen et al, 1995; van Dartel et al, 2002, 2004; Bayani et al, 2003; Henriksen et al, 2003; Squire et al, 2003; Lau et al, 2004; Both et al, 2016), the TOP3A gene was always present in the amplicon, that is, all amplifications included TOP3A, among a number of other genes (Fig 3B).