HIF1A and neuroblastoma: In this study, mitochondrial DNA (mtDNA) enriched (SK-N-AS) and depleted (ρ0) cells of neuroblastoma were cultured in a hypoxic chamber to simulate a hypoxic condition and then the major components involved in mitochondrial related pathways, hypoxia-inducible factor 1α (HIF-1α) and reactive oxygen species (ROS) were measured.