title: Modulation of major histocompatibility complex class 1 genes in human retinoblastoma cells by interferons.
abstract: OBJECTIVE
  To examine the mechanism(s) of interferon (IFN) induced expression of major histocompatibility complex (MHC) class 1 molecules on the human retinoblastoma cell line, Y-79.
  
  
  METHODS
  Y-79 cells were incubated in the presence of IFN-alpha, -beta, and -gamma. Y-79 cell expression of MHC class 1 molecules was measured by flow cytometric analysis. HLA-B7 and oncogene transcription were evaluated by Northern blot analysis and nuclear runoff transcription assays.
  
  
  RESULTS
  IFN-gamma increased MHC-class 1 antigen expression and induced a fivefold increase in its transcription rate. Posttranscriptionally, IFN-beta and -gamma increased steady state messenger RNA for the HLA-B7 gene. These effects were not associated with down regulation of N-myc oncogene nuclear transcription. Moreover, dexamethasone did not affect the IFN-gamma induced expression of MHC-class 1 molecules.
  
  
  CONCLUSIONS
  Both transcriptional and posttranscriptional mechanisms are implicated in the modulation of class 1 molecule expression by IFN. In addition, this modulation is not associated with down regulation of N-myc oncogene expression. Spontaneous or IFN-gamma induced MHC class 1 antigen expression in retinoblastoma Y-79 cells is resistant to glucocorticoid hormones.
authors.affiliation: Immunology and Virology Section, National Eye Institute, National Institutes of Health, Bethesda, MD 20892.
authors.forename: S
authors.initials: S
authors.lastname: Barez
authors.forename: D T
authors.initials: DT
authors.lastname: Boumpas
authors.forename: C M
authors.initials: CM
authors.lastname: Percopo
authors.forename: E D
authors.initials: ED
authors.lastname: Anastassiou
authors.forename: J J
authors.initials: JJ
authors.lastname: Hooks
authors.forename: B
authors.initials: B
authors.lastname: Detrick
mesh_terms: D015152:Blotting, Northern; D003907:Dexamethasone / Q000494:pharmacology; D005134:Eye Neoplasms / Q000378:metabolism*; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D005805:Genes, MHC Class I; D015793:HLA-B7 Antigen / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007372:Interferons / Q000494:pharmacology*; D016271:Proto-Oncogene Proteins c-myc / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D012175:Retinoblastoma / Q000378:metabolism*; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured
chemical_list: D015793:HLA-B7 Antigen; D016271:Proto-Oncogene Proteins c-myc; D012333:RNA, Messenger; D003907:Dexamethasone; D007372:Interferons