title: Stimulation of DNA synthesis in calcium-deprived T51B liver cells by the tumor promoters phenobarbital, saccharin, and 12-O-tetradecanoylphorbol-13-acetate.
abstract: Extracellular calcium deprivation arrested the proliferative development of T51B rat liver cells in late G1 or S phases. These arrested cells initiated DNA synthesis within an hr after addition of calcium or a tumor promoter such as phorbol-12,13-didecanoate, phenobarbital, saccharin, or 12-O-tetradecanoylphorbol-13-acetate. Nonpromoting relatives of 12-O-tetradecanoylphorbol-13-acetate such as phorbol, 4-O-methyl-12-O-tetradecanoylphorbol-13-acetate, and 4 alpha-phorbol-12,13-didecanoate were unable significantly to induce the calcium-deprived cells to initiate DNA synthesis. It is suggested that an ability to elicit a prompt DNA-synthetic response from calcium-deprived cells might be a useful in vitro indicator of tumor-promoting potential.
mesh_terms: D000818:Animals; D002118:Calcium / Q000172:deficiency*; D002453:Cell Cycle / Q000187:drug effects; D002478:Cells, Cultured; D003043:Cocarcinogenesis; D004247:DNA / Q000096:biosynthesis*; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D010634:Phenobarbital / Q000494:pharmacology*; D010703:Phorbol Esters / Q000494:pharmacology; D010704:Phorbols / Q000494:pharmacology*; D051381:Rats; D012439:Saccharin / Q000494:pharmacology*; D013268:Stimulation, Chemical; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D010703:Phorbol Esters; D010704:Phorbols; D004247:DNA; D012439:Saccharin; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium; D010634:Phenobarbital