title: Inhibitory effect of 5-halogenated deoxyuridines on in vitro keratinization of a transformed rat urinary bladder epithelial cell line.
abstract: The effect of 5-halogenated deoxyuridines on the keratinization of an in vitro-transformed rat bladder epithelial cell line, BES20B, was studied by a cover slip culture method established previously. 5-Bromodeoxyuridine (BrdU) and 5-iododeoxyuridine (IdU) both showed dose-dependent inhibition of the keratinization. The complete inhibition of keratinization was achieved by BrdU at concentrations higher than 5 microgram/ml. At these concentrations, BrdU reduced the saturation density of the test cells on a cover slip. Removal of BrdU from the culture medium restored the cell growth as well as the keratinization of BrdU-treated cells, suggesting that the effect of BrdU is reversible. The effect of BrdU was abolished by the addition of excess thymidine. A possible mechanism of the anti-keratinization effect of BrdU is discussed in comparison with that of vitamin A.
mesh_terms: D000818:Animals; D001667:Binding, Competitive; D001973:Bromodeoxyuridine / Q000494:pharmacology*; D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D004261:DNA Replication / Q000187:drug effects; D004848:Epithelium; D005467:Floxuridine / Q000494:pharmacology*; D007065:Idoxuridine / Q000494:pharmacology*; D007633:Keratins / Q000378:metabolism*; D012334:RNA, Neoplasm / Q000096:biosynthesis; D051381:Rats; D013936:Thymidine / Q000378:metabolism; D001749:Urinary Bladder Neoplasms / Q000378:metabolism*; D014801:Vitamin A / Q000494:pharmacology
chemical_list: D012334:RNA, Neoplasm; D005467:Floxuridine; D014801:Vitamin A; D007633:Keratins; D001973:Bromodeoxyuridine; D007065:Idoxuridine; D013936:Thymidine