title: Activin inhibits cell growth and induces differentiation in human retinoblastoma y79 cells.
abstract: OBJECTIVE
  Activin is a member of the transforming growth factor-beta (TGF-beta) superfamily and exerts certain effects on differentiation and apoptosis. We investigated the effects of activin on retinoblastoma cell line.
  
  
  METHODS
  We used retinoblastoma cell line Y79. Intracellular signal transduction of activin was investigated with RT-PCR, immunofluorescence study, and luciferase reporter assay. The effect of activin on cell growth was examined with fluorescence cell viability assays. To determine the effect of activin on apoptosis, a TUNEL assay and an immunofluorescence study of cleaved PARP were performed. The effect of activin on cell differentiation was examined with RT-PCR and Western blotting.
  
  
  RESULTS
  Intracellular signal transduction of activin was confirmed in Y79 cells. Activin inhibited Y79 cell growth. Activin induced the expression of neural retina leucine zipper (Nrl) at the mRNA and protein levels.
  
  
  CONCLUSIONS
  Nrl is a specific gene in rod photoreceptor development and is a gene indispensable to differentiation into rod photoreceptors, so the present results suggest that activin affects the differentiation of retinoblastoma cells into rod photoreceptor cells.
authors.affiliation: Department of Ophthalmology and Visual Science, Yamagata University School of Medicine, Yamagata, Japan.
authors.forename: Chikako
authors.initials: C
authors.lastname: Kanno
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Kashiwagi
authors.forename: Kuniko
authors.initials: K
authors.lastname: Horie
authors.forename: Motoko
authors.initials: M
authors.lastname: Inomata
authors.forename: Teiko
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Chifumi
authors.initials: C
authors.lastname: Kitanaka
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Yamashita
mesh_terms: D028341:Activins / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D050976:Basic-Leucine Zipper Transcription Factors / Q000235:genetics / Q000378:metabolism; D015153:Blotting, Western; D002454:Cell Differentiation / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects*; D002470:Cell Survival; D005136:Eye Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D020287:In Situ Nick-End Labeling; D012333:RNA, Messenger / Q000378:metabolism; D012160:Retina / Q000378:metabolism; D019572:Retinal Neoplasms / Q000473:pathology*; D017948:Retinal Rod Photoreceptor Cells / Q000473:pathology; D012175:Retinoblastoma / Q000473:pathology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects; D014407:Tumor Cells, Cultured
chemical_list: D050976:Basic-Leucine Zipper Transcription Factors; D005136:Eye Proteins; C084884:Nrl protein, mouse; D012333:RNA, Messenger; D028341:Activins