title: Leukemia inhibitory factor and ciliary neurotrophic factor increase activated Ras in a neuroblastoma cell line and in sympathetic neuron cultures.
abstract: The cytokines leukemia inhibitory factor (LIF) and ciliary neurotrophic factor (CNTF) have been implicated in determination of neuronal phenotype as well as promotion of neuronal survival. However, the intracellular mechanisms by which their signals are transduced remain poorly understood. We have previously studied the regulation of vasoactive intestinal polypeptide gene expression by LIF and CNTF in the NBFL neuroblastoma cell line. Because these cytokines induce tyrosine phosphorylation that may lead to Ras activation, we explored a possible role for Ras in LIF- and CNTF-induced signal transduction. In NBFL cells LIF increases activated Ras in a rapid, transient, and concentration-dependent manner. CNTF and a related cytokine, oncostatin M, produce similar increases. CNTF and LIF also increase activated Ras in neuron-enriched dissociated cultures of sympathetic ganglia. Moreover, these cytokines rapidly and transiently induce specific tyrosine-phosphorylated proteins, p165 and p195. The protein kinase inhibitors K252a and staurosporine block LIF-induced increases in tyrosine phosphorylation, activated Ras, and vasoactive intestinal polypeptide mRNA in NBFL cells. These data support a possible role for Ras in the cell differentiation effects of LIF and CNTF.
authors.affiliation: Department of Neurology, Massachusetts General Hospital, Boston 02129.
authors.forename: M A
authors.initials: MA
authors.lastname: Schwarzschild
authors.forename: W T
authors.initials: WT
authors.lastname: Dauer
authors.forename: S E
authors.initials: SE
authors.lastname: Lewis
authors.forename: L K
authors.initials: LK
authors.lastname: Hamill
authors.forename: J S
authors.initials: JS
authors.lastname: Fink
authors.forename: S E
authors.initials: SE
authors.lastname: Hyman
mesh_terms: D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D000470:Alkaloids / Q000494:pharmacology; D000818:Animals; D000831:Animals, Newborn; D015153:Blotting, Western; D002227:Carbazoles / Q000494:pharmacology; D002460:Cell Line; D002478:Cells, Cultured; D020934:Ciliary Neurotrophic Factor; D016207:Cytokines / Q000494:pharmacology; D006131:Growth Inhibitors / Q000494:pharmacology*; D026121:Indole Alkaloids; D015850:Interleukin-6 / Q000494:pharmacology; D007546:Isoquinolines / Q000494:pharmacology; D053605:Leukemia Inhibitory Factor; D008222:Lymphokines / Q000494:pharmacology*; D009414:Nerve Growth Factors / Q000494:pharmacology; D009419:Nerve Tissue Proteins / Q000494:pharmacology*; D009447:Neuroblastoma; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D053683:Oncostatin M; D010455:Peptides / Q000494:pharmacology; D010879:Piperazines / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D047428:Protein Kinase Inhibitors; D012313:RNA / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D051381:Rats; D019311:Staurosporine; D017783:Superior Cervical Ganglion / Q000378:metabolism*; D014407:Tumor Cells, Cultured; D014660:Vasoactive Intestinal Peptide / Q000096:biosynthesis; D018631:ras Proteins / Q000378:metabolism*
chemical_list: D000470:Alkaloids; D002227:Carbazoles; D020934:Ciliary Neurotrophic Factor; D016207:Cytokines; D006131:Growth Inhibitors; D026121:Indole Alkaloids; D015850:Interleukin-6; D007546:Isoquinolines; D053605:Leukemia Inhibitory Factor; D008222:Lymphokines; D009414:Nerve Growth Factors; D009419:Nerve Tissue Proteins; D010455:Peptides; D010879:Piperazines; D047428:Protein Kinase Inhibitors; D012333:RNA, Messenger; D053683:Oncostatin M; D014660:Vasoactive Intestinal Peptide; D012313:RNA; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; C049985:staurosporine aglycone; D011493:Protein Kinase C; D018631:ras Proteins; D019311:Staurosporine