title: Antitumour effect of valproic acid against salivary gland cancer in vitro and in vivo.
abstract: Salivary gland cancer (SGC) has a comparatively poor prognosis and is prone to frequent recurrence and metastases. Therefore, the development of more effective chemotherapy against SGC is desirable. The aim of the present study was to investigate the antitumour effects of valproic acid (VPA) against SGC in vitro and in vivo. Two human SGC cell lines (HSY and HSG cells) were used in the present study. The effects of VPA on the proliferation of SGC cells in vitro were assessed by MTT assay. Cancer cells treated with VPA were subjected to cell cycle analysis by flow cytometry. In addition, the expression levels of p21 and p27 were examined by real-time RT-PCR to identify the mechanisms of the antitumour effect of VPA on SGC. The effects of VPA on cancer growth in vivo were evaluated in a xenograft model. VPA inhibited the proliferation of SGC cells in a dose-dependent manner in vitro. Degenerated cancer cells were observed at high concentrations of VPA. In the cell cycle analysis, VPA induced cell-growth inhibition and G1 arrest of cell cycle progression in both cancer cell lines in a time- and dose-dependent manner. VPA markedly upregulated the mRNA expression levels of both p21 and p27 in both SGC cell lines in a time-dependent manner. In the xenograft model experiment, VPA treatment markedly inhibited the growth of salivary gland tumours when compared with the growth of the untreated controls. VPA may be a valuable drug in the development of better therapeutic regimens for SGC.
authors.affiliation: Department of Oral Surgery, Subdivision of Molecular Oral Medicine, Division of Integrated Sciences of Translational Research, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8504, Japan.
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Nagai
authors.affiliation: Department of Oral Surgery, Subdivision of Molecular Oral Medicine, Division of Integrated Sciences of Translational Research, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8504, Japan.
authors.forename: Masako
authors.initials: M
authors.lastname: Fujioka-Kobayashi
authors.affiliation: Department of Oral Surgery, Subdivision of Molecular Oral Medicine, Division of Integrated Sciences of Translational Research, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8504, Japan.
authors.forename: Go
authors.initials: G
authors.lastname: Ohe
authors.affiliation: Department of Oral Surgery, Subdivision of Molecular Oral Medicine, Division of Integrated Sciences of Translational Research, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8504, Japan.
authors.forename: Kanae
authors.initials: K
authors.lastname: Hara
authors.affiliation: Department of Oral Surgery, Subdivision of Molecular Oral Medicine, Division of Integrated Sciences of Translational Research, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8504, Japan.
authors.forename: Natsumi
authors.initials: N
authors.lastname: Takamaru
authors.affiliation: Department of Oral Surgery, Subdivision of Molecular Oral Medicine, Division of Integrated Sciences of Translational Research, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8504, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Uchida
authors.affiliation: Department of Oral Surgery, Subdivision of Molecular Oral Medicine, Division of Integrated Sciences of Translational Research, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8504, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Tamatani
authors.affiliation: Department of Oral Surgery, Subdivision of Molecular Oral Medicine, Division of Integrated Sciences of Translational Research, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8504, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Fujisawa
authors.affiliation: Department of Oral Surgery, Subdivision of Molecular Oral Medicine, Division of Integrated Sciences of Translational Research, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima 770-8504, Japan.
authors.forename: Youji
authors.initials: Y
authors.lastname: Miyamoto
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy* / Q000378:metabolism; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics / Q000378:metabolism; D050760:Cyclin-Dependent Kinase Inhibitor p27 / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D012468:Salivary Gland Neoplasms / Q000188:drug therapy* / Q000378:metabolism; D014635:Valproic Acid / Q000494:pharmacology*; D023041:Xenograft Model Antitumor Assays
chemical_list: D000970:Antineoplastic Agents; C493956:CDKN1A protein, human; C436291:CDKN1B protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050760:Cyclin-Dependent Kinase Inhibitor p27; D014635:Valproic Acid