Interestingly, this up-regulation of BRD7 by the knockdown of Cdh1 or Cdc20 appears to be specific in osteosarcoma cell lines, including U2OS and its derivative line U2OS/MTX300, as well as SAOS2 and MG63 cells (Fig. 1D), because this phenomenon was not observed in other cell lines such as HeLa, HepG2, HCT116, MCF7 and CNE2 (Fig. S3). The gene discussed is BRD7; the disease is osteosarcoma.