HES1 and neuroblastoma: These observations reveal that intermittent hypoxia-exposed cultured human neuroblastoma cells exhibit downregulation of SNS marker genes, such as the neurofilament genes NPY, HASH-1 and dHAND, as well as upregulation of genes expressed in the neural crest, e.g., ID2, HES-1, c-Kit and Notch-1.