sentences:  CpG islands commonly function to silence expression of adjacent genes while their methylation inhibits this silencing.Hypomethylation of CpG islands upstream of FGFR1 is hypothesized to be at least in part responsible for the over-expression of FGFR1 by and malignant behavior of these rhabdomyosarcoma tumors.In addition, a single case of rhabdomyosarcoma tumor was found express co-amplified "FOXO1" gene at 13q14 and "FGFR1" gene at 8p11, i.e.