title: Diverse effects: augmentation, inhibition, and non-efficacy of 12-O-tetradecanoylphorbol-13-acetate (TPA) on retrovirus genome expression in vivo and in vitro.
abstract: The action of 12-O-tetradecanoylphorbol-13-acetate (TPA) on several retrovirus-related functions was investigated in four virus-host cell systems. The following effects were recorded: (i) in STU-mice, infected with the Friend virus complex (Friend) murine leukaemia virus/Friend spleen focus forming virus) and treated with TPA (50 ng/g) for one week prior to infection, the number of spleen foci increased 5-fold over the control. (ii) Addition of TPA (0.04 to 40 ng/ml) to virus-producing cell systems resulted in a 2-fold increase of extracellular reverse transcriptase activity. The maximum response was observed in Friend leukemia virus-producing mouse cells at 0.1 to 0.4 ng TPA/ml and in simian sarcoma virus-producing rat cells at 4 ng/ml. (iii) The efficiency of transformation of BalbC 3T3 cells by Moloney murine sarcoma virus, tested in a focus formation assay, was slightly enhanced by TPA. (iv) TPA inhibited the induction of endogenous virus formation in B cell mitogen-stimulated spleen cell cultures from BalbC mice.
mesh_terms: D000818:Animals; D002460:Cell Line; D002472:Cell Transformation, Viral / Q000187:drug effects; D003043:Cocarcinogenesis; D005260:Female; D005622:Friend murine leukemia virus / Q000187:drug effects* / Q000235:genetics; D005814:Genes, Viral / Q000187:drug effects; D007942:Leukemia, Experimental / Q000378:metabolism*; D051379:Mice; D008815:Mice, Inbred Strains; D010704:Phorbols / Q000494:pharmacology*; D012194:RNA-Directed DNA Polymerase / Q000096:biosynthesis*; D051381:Rats; D012842:Sarcoma Virus, Woolly Monkey / Q000187:drug effects / Q000235:genetics; D013539:Simian virus 40 / Q000235:genetics; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014412:Tumor Virus Infections / Q000201:enzymology; D014775:Virus Activation / Q000187:drug effects
chemical_list: D010704:Phorbols; D012194:RNA-Directed DNA Polymerase; D013755:Tetradecanoylphorbol Acetate