title: Relationship of cellular oncogene expression to inhibition of growth and induction of differentiation of Daudi cells by interferons or TPA.
abstract: Human alpha or beta interferons inhibit the proliferation of Daudi Burkitt lymphoma cells and induce the differentiation of these cells towards a mature plasma cell phenotype. Similar responses are seen when Daudi cells are treated with the phorbol ester, TPA. Both interferons and TPA down-regulate expression of the c-myc oncogene in these cells. Although TPA can mimic the effect of interferon on cell differentiation, it does not induce 2'5' oligoadenylate synthetase or the interferon-sensitive mRNAs, 6-16 or 9-27. Thus chronic stimulation of protein kinase C by TPA cannot mimic all of the effects of interferon treatment on gene expression. Inhibition of ADP-ribosyl transferase activity by 3-methoxybenzamide impairs interferon- or TPA-induced differentiation of Daudi cells. This agent induces a higher level of c-myc mRNA in the cells and stimulates the incorporation of [3H]thymidine into DNA; although these effects are partially counteracted by interferon or TPA treatment, the elevated expression of the c-myc gene may be sufficient to prevent terminal differentiation and allow cell proliferation to continue.
authors: Department of Biochemistry, St. George's Hospital Medical School, London, England.
authors: M J
authors: MJ
authors: Clemens
authors: V J
authors: VJ
authors: Tilleray
authors: R
authors: R
authors: James
authors: D R
authors: DR
authors: Gewert
mesh_terms: D001549:Benzamides / Q000494:pharmacology; D002051:Burkitt Lymphoma; D002454:Cell Differentiation; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D004261:DNA Replication / Q000187:drug effects; D005786:Gene Expression Regulation; D006801:Humans; D007372:Interferons / Q000502:physiology*; D011519:Proto-Oncogenes / Q000187:drug effects; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014158:Transcription, Genetic / Q000187:drug effects
chemical_list: D001549:Benzamides; D012333:RNA, Messenger; D007372:Interferons; C025159:3-methoxybenzamide; D013755:Tetradecanoylphorbol Acetate