title: Effect of 5-fluorouracil on G1 phase cell cycle regulation in oral cancer cell lines.
abstract: 5-fluorouracil (5-FU) has been widely used for chemotherapy of head and neck cancer, and is known to affect the cell cycle and induce apoptotic death of cancer cells. However, the molecular actions of 5-FU on the cell cycle regulatory mechanism have not been fully explained. Herein we analyzed the effects of 5-FU on the expression of G1/S-related cell cycle regulators in oral cancer cell lines. In vitro 5-FU treatment of oral cancer cells resulted in an increase in G1/S phase cells. p21 expression was augmented by 5-FU without any notable changes in p53 expression. A remarkable up-regulation of cyclin E and a concomitant down-regulation of cyclin D were observed after 24 h 5-FU treatment. Our results suggest that 5-FU-induced changes in cell cycle regulation of oral cancer cells might associate with an alteration of G1 cyclins expression. p21 was remarkably up-regulated, but it was speculated that its activity might be cancelled by an increased binding to CDK4.
authors.affiliation: Second Department of Oral and Maxillofacial Surgery, School of Dentistry, Showa University, Tokyo 145-8515, Japan. meiko@senzoku.showa-u.ac.jp
authors.forename: Ming-Heng
authors.initials: MH
authors.lastname: Li
authors.forename: Daisuke
authors.initials: D
authors.lastname: Ito
authors.forename: Misaki
authors.initials: M
authors.lastname: Sanada
authors.forename: Takeshi
authors.initials: T
authors.lastname: Odani
authors.forename: Masashi
authors.initials: M
authors.lastname: Hatori
authors.forename: Masayasu
authors.initials: M
authors.lastname: Iwase
authors.forename: Masao
authors.initials: M
authors.lastname: Nagumo
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000494:pharmacology; D015153:Blotting, Western; D018797:Cell Cycle Proteins / Q000378:metabolism; D045744:Cell Line, Tumor; D002945:Cisplatin / Q000494:pharmacology; D050762:Cyclin-Dependent Kinase Inhibitor p15; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050760:Cyclin-Dependent Kinase Inhibitor p27; D016213:Cyclins / Q000378:metabolism; D004273:DNA, Neoplasm / Q000378:metabolism; D005472:Fluorouracil / Q000494:pharmacology*; D016193:G1 Phase / Q000187:drug effects*; D006801:Humans; D009062:Mouth Neoplasms / Q000188:drug therapy*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000378:metabolism
chemical_list: D000964:Antimetabolites, Antineoplastic; D000970:Antineoplastic Agents; C493956:CDKN1A protein, human; C493966:CDKN2B protein, human; D018797:Cell Cycle Proteins; D050762:Cyclin-Dependent Kinase Inhibitor p15; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D004273:DNA, Neoplasm; D016159:Tumor Suppressor Protein p53; D025521:Tumor Suppressor Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27; D002945:Cisplatin; D005472:Fluorouracil