title: Tumor promotion by phorbol esters in skin: evidence for a memory effect.
abstract: By means of a two-stage promotion protocol in mouse epidermis with 12-O-tetradecanoylphorbol-13-acetate as first-stage promoter and 12-O-retinoylphorbol-13-acetate as second-stage promoter, the effects of the former that are critical and obligatory for tumor promotion were shown to be irreversible in nature for at least 8 weeks. The reversibility of tumor promotion was related to the second stage of promotion, reflecting the reversibility of epidermal hyperplasia induced by 12-O-tetradecanoylphorbol-13-acetate.
mesh_terms: D000818:Animals; D002273:Carcinogens / Q000494:pharmacology*; D002460:Cell Line; D004817:Epidermis / Q000187:drug effects; D005260:Female; D006965:Hyperplasia / Q000139:chemically induced; D051379:Mice; D008815:Mice, Inbred Strains; D009374:Neoplasms, Experimental / Q000139:chemically induced; D010703:Phorbol Esters / Q000009:adverse effects*; D010704:Phorbols / Q000009:adverse effects*; D011230:Precancerous Conditions / Q000139:chemically induced; D012878:Skin Neoplasms / Q000139:chemically induced*; D013755:Tetradecanoylphorbol Acetate / Q000009:adverse effects*; D013997:Time Factors
chemical_list: D002273:Carcinogens; D010703:Phorbol Esters; D010704:Phorbols; C032974:12-O-retinoylphorbol-13-acetate; D013755:Tetradecanoylphorbol Acetate