title: Arrest of cultured cells in the G1 phase of the cell cycle by indomethacin.
abstract: Indomethacin reversibly inhibited growth of rat hepatoma cells (HTC) and human diploid fibroblasts in the G1 phase of the cell cycle. Cytophotometric measurements showed that greater than 90% of cells incubated for 48 hr with indomethacin had a DNA content that corresponded to the G1 state. Synchronous growth of both the HTC and fibroblast cultures occurred after removal of drug as indicated by the sequence of changes in [3H]thymidine incorporation into DNA, cellular DNA content, mitotic index and cell number. Autoradiographs of HTC cell cultures incubated with [3H]thymidine indicated that all (98%) of the cells engaged in DNA synthesis following the removal of indomethacin. Since viability of the cells was not impaired, even by prolonged exposure to indomethacin, this drug provides a means of synchronizing growth. Suppression of cell proliferation could contribute to the therapeutic and/or toxic effects of indomethacin in vivo.
mesh_terms: D000818:Animals; D001345:Autoradiography; D002453:Cell Cycle / Q000187:drug effects*; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis; D005347:Fibroblasts / Q000166:cytology; D006801:Humans; D007213:Indomethacin / Q000494:pharmacology*; D007399:Interphase / Q000187:drug effects*; D007700:Kinetics; D008114:Liver Neoplasms, Experimental / Q000473:pathology; D008940:Mitotic Index / Q000187:drug effects; D051381:Rats; D013997:Time Factors
chemical_list: D004247:DNA; D007213:Indomethacin