title: Expressional changes after histone deacetylase inhibition by valproic acid in LNCaP human prostate cancer cells.
abstract: Pathogenesis of prostate cancer is paralleled by aberrant transcriptional regulation which involves gene silencing by histone deacetylases. In cancer cells, inhibitors of histone deacetylases such as valproic acid can act as differentiation agents which relieve pro-apoptotic factors from transcriptional repression. We investigated the potential of the well-tolerated anticonvulsant valproic acid in prostate cancer cell line LNCaP and analyzed the activation of pro-apoptotic factors and resulting apoptosis. We used real time RT-PCR to quantify the mRNA expression of prostate-specific antigen, prostate-derived Ets transcription factor, tissue inhibitor of matrix metalloproteinase-3 and insulin-like growth factor binding protein-3. An automated sandwich-ELISA was used to measure secretion of prostate-specific antigen in conditioned cell culture media of LNCaP prostate cancer cells. Apoptotic cells were detected cytochemically and by applying immunocytochemistry. Activity of histone deacetylases in nuclear extracts was measured with a colorimetric assay kit. Valproic acid treatment caused a marked inhibition of histone deacetylases activity. Expression of prostate-derived Ets transcription factor and consequently prostate-specific antigen were down-regulated to basal levels in LNCaP cells. Pro-apoptotic factor caspase-3, tissue inhibitor of matrix metalloproteinase-3 and insulin-like growth factor binding protein-3 were up-regulated resulting in apoptosis of tumor cells. Valproic acid mediates marked effects on the expression of genes relevant in proliferation and apoptosis. Our study provides strong evidence that prostate cancer may benefit particularly from anti-proliferative stimuli from this well established drug.
authors.affiliation: Department of Urology, Georg-August-University, D-37075 Göttingen, Germany. pthelen@gwdg.de
authors.forename: Paul
authors.initials: P
authors.lastname: Thelen
authors.forename: Stefan
authors.initials: S
authors.lastname: Schweyer
authors.forename: Bernhard
authors.initials: B
authors.lastname: Hemmerlein
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Wuttke
authors.forename: Florian
authors.initials: F
authors.lastname: Seseke
authors.forename: Rolf-Hermann
authors.initials: RH
authors.lastname: Ringert
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D053148:Caspase 3; D020169:Caspases / Q000235:genetics; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D006367:HeLa Cells; D056572:Histone Deacetylase Inhibitors; D006655:Histone Deacetylases / Q000378:metabolism; D006801:Humans; D006877:Hydroxamic Acids / Q000494:pharmacology; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000235:genetics; D008297:Male; D017430:Prostate-Specific Antigen / Q000235:genetics; D011471:Prostatic Neoplasms / Q000201:enzymology / Q000235:genetics / Q000473:pathology; D050783:Proto-Oncogene Proteins c-ets; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D011944:Receptors, Androgen / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D019717:Tissue Inhibitor of Metalloproteinase-3 / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics; D014635:Valproic Acid / Q000494:pharmacology*
chemical_list: D004791:Enzyme Inhibitors; D056572:Histone Deacetylase Inhibitors; D006877:Hydroxamic Acids; D018972:Insulin-Like Growth Factor Binding Protein 3; D050783:Proto-Oncogene Proteins c-ets; D012333:RNA, Messenger; D011944:Receptors, Androgen; C403974:SPDEF protein, human; D019717:Tissue Inhibitor of Metalloproteinase-3; D014157:Transcription Factors; C012589:trichostatin A; D014635:Valproic Acid; D017430:Prostate-Specific Antigen; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases; D006655:Histone Deacetylases