title: Differential expression of N-myc and c-src proto-oncogenes during neuronal and schwannian differentiation of human neuroblastoma cells.
abstract: Neuroblastoma (NB) cells can be induced to differentiate bidirectionally into either neuronal or schwannian cells by different inducers. However, the underlying mechanisms are poorly understood. We examined the expression of N-myc and c-src genes in 3 human NB-cell lines during either neuronal or schwannian differentiation in vitro, since proto-oncogenes are considered to play a pivotal role in regulating cell proliferation and differentiation. Decreased N-myc expression and increased c-src expression were observed during neuronal differentiation by retinoic acid, polyprenoic acid (E5166) and dibutyryl cyclic AMP, whereas the expression of N-myc and c-src genes was considerably reduced during schwannian differentiation by bromodeoxyuridine, demonstrating that the expression of N-myc and c-src genes was regulated independently in the bipolar differentiation processes of NB cells. Our results suggest that enhanced N-myc expression might be closely linked to the undifferentiated phenotypes of NB cells, that c-src expression might be related to the neuronal differentiation of NB cells, and that N-myc and c-src genes might be regulated independently in the determination of the bipolar differentiation of NB cells.
authors.affiliation: Department of Pediatrics, Children's Research Hospital, Kyoto, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Horii
authors.forename: T
authors.initials: T
authors.lastname: Sugimoto
authors.forename: T
authors.initials: T
authors.lastname: Sawada
authors.forename: J
authors.initials: J
authors.lastname: Imanishi
authors.forename: K
authors.initials: K
authors.lastname: Tsuboi
authors.forename: M
authors.initials: M
authors.lastname: Hatanaka
mesh_terms: D002454:Cell Differentiation; D005784:Gene Amplification; D006801:Humans; D009447:Neuroblastoma / Q000235:genetics* / Q000473:pathology; D009474:Neurons / Q000473:pathology*; D009857:Oncogenes; D012583:Schwann Cells / Q000473:pathology*; D014407:Tumor Cells, Cultured