title: Factors which disorganize microtubules or microfilaments increase the frequency of cell transformation by polyoma virus.
abstract: Griseofulvin, 12-O-tetradecanoyl phorbol-13-acetate, melittin, epidermal growth factor, vinblastine, cytochalasin B, podophyllotoxin, colcemid, and colchicine were unable to transform cells but could increase from 8- to 40-fold the frequency of cell transformation by polyoma virus. The 3T3-like cells were resting at confluence and were exposed to the drug only during the 1st week after viral infection. Griseofulvin, a tumor promoter, reduced or increased the frequency of transformation depending on the dose with which the infected cells were treated. The antitumor activity of tumor promoters is discussed.
mesh_terms: D002460:Cell Line; D002471:Cell Transformation, Neoplastic / Q000187:drug effects*; D002472:Cell Transformation, Viral / Q000187:drug effects*; D003078:Colchicine / Q000494:pharmacology; D003571:Cytochalasin B / Q000494:pharmacology; D004815:Epidermal Growth Factor / Q000494:pharmacology; D006118:Griseofulvin / Q000494:pharmacology; D008555:Melitten / Q000494:pharmacology; D009153:Mutagens / Q000494:pharmacology; D011034:Podophyllotoxin / Q000494:pharmacology; D011120:Polyomavirus / Q000502:physiology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014747:Vinblastine / Q000494:pharmacology
chemical_list: D009153:Mutagens; D008555:Melitten; D006118:Griseofulvin; D003571:Cytochalasin B; D014747:Vinblastine; D004815:Epidermal Growth Factor; D011034:Podophyllotoxin; D013755:Tetradecanoylphorbol Acetate; D003078:Colchicine