title: Interferon regulates expression of mda-6/WAF1/CIP1 and cyclin-dependent kinases independently from p53 in B16 murine melanoma cells.
abstract: Interferons (IFNs) induce growth arrest and terminal differentiation through regulation of proliferative genes in a variety of cell types including tumor cells. Growth of melanoma cells is believed to be controlled by the cyclin-dependent kinase inhibitor, mda-6/WAF1/CIP1 gene. IFNs affect the expression of WAF1 in several cell types, including human melanomas. In our earlier reports we demonstrated the antitumor and anticellular activities of different IFN-types on B16 murine melanoma cells. The present study aimed to demonstrate the involvement of mda-6/WAF1 and related cyclin-dependent kinases in antitumor action of different IFN-types in B16 melanoma cells. IFN-alpha has been proven to be a potent inducer of mda-6/WAF1, also inhibiting cyclin-dependent kinases, such as cdc2- and cdk2-kinase. This induction is p53-independent. However, IFN-gamma affects B16 cells differently, it induces p53 activity without inducing WAF1. The combination of IFN-alpha plus IFN-gamma is additive rather than synergistic. Our data demonstrate differential effects of different IFNs on murine B16 melanoma cells which may have relevance in nonsurgical treatment of melanomas.
authors.affiliation: Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston 77555-1019, USA. Istvan.Arany@UTMB.edu
authors.forename: I
authors.initials: I
authors.lastname: Arany
authors.forename: C M
authors.initials: CM
authors.lastname: Fleischmann
authors.forename: S K
authors.initials: SK
authors.lastname: Tyring
authors.forename: W R
authors.initials: WR
authors.lastname: Fleischmann
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects / Q000235:genetics; D050759:Cyclin-Dependent Kinase Inhibitor p21; D018844:Cyclin-Dependent Kinases / Q000235:genetics / Q000378:metabolism*; D016213:Cyclins / Q000235:genetics / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D007370:Interferon Type I / Q000494:pharmacology*; D007371:Interferon-gamma / Q000494:pharmacology*; D008546:Melanoma, Experimental / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D011994:Recombinant Proteins; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*
chemical_list: C493956:CDKN1A protein, human; C493957:Cdkn1a protein, mouse; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D004791:Enzyme Inhibitors; D007370:Interferon Type I; D011994:Recombinant Proteins; D016159:Tumor Suppressor Protein p53; D007371:Interferon-gamma; D018844:Cyclin-Dependent Kinases