HIF-1α expression and induction following hypoxia has been reported in PC12 and NT2 cells [61,62] and neuroblastoma cells [59], therefore our observed lack of HIF-1α induction and signalling following acute hypoxia, as well as through chemical induction of hypoxia, using colbalt chloride (data not shown), was surprising. The gene discussed is HIF1A; the disease is neuroblastoma.