title: Synergistic interaction between the HDAC inhibitor, MPT0E028, and sorafenib in liver cancer cells in vitro and in vivo.
abstract: OBJECTIVE
  To investigate the antitumor activities of a histone deacetylase (HDAC) inhibitor, MPT0E028, plus sorafenib in liver cancer cells in vitro and in vivo.
  
  
  METHODS
  Different liver cancer cell lines were exposed to sorafenib in the presence or absence of MPT0E028, and cell viability was determined by MTT assay. Effects of combined treatment on cell cycle and intracellular signaling pathways were assessed by flow cytometry and Western blot analysis. The Hep3B xenograft model was used to examine the antitumor activity in vivo.
  
  
  RESULTS
  Our data indicate that sorafenib and MPT0E028 synergistically reduced cell viability in liver cancer cells, and also markedly induced apoptotic cell death in these cells, as evidenced by the cleavage of caspase-3, PARP, and DNA fragmentation. MPT0E028 altered the global modifications of histone and nonhistone proteins regardless of the presence of sorafenib. However, sorafenib blocked MPT0E028-induced Erk activation and its downstream signaling cascades, such as Stat3 phosphorylation (Ser(727)) and Mcl-1 upregulation. Ectopic expression of constitutively active Mek successively reversed the apoptosis triggered by the combined treatment. Pharmacologic inhibition of Mek by PD98059 potentiated MPT0E028-induced apoptosis, suggesting that the synergistic interaction between MPT0E028 and sorafenib occurs at least partly through inhibition of Erk signaling. The data demonstrated that transcriptional activation of fibroblast growth factor receptor 3 (FGFR3) contributes to MPT0E028-mediated Erk phosphorylation. Finally, MPT0E028 plus sorafenib significantly improved the tumor growth delay (TGD) in a Hep3B xenograft model.
  
  
  CONCLUSIONS
  These findings suggest that MPT0E028 in combination with sorafenib has significant anti-hepatocellular carcinoma activity in preclinical models, potentially suggesting a novel therapeutic strategy for patients with advanced hepatocellular carcinoma.
authors: Pharmacological Institute, College of Medicine, National Taiwan University, Taipei, Taiwan.
authors: Chun-Han
authors: CH
authors: Chen
authors: Pharmacological Institute, College of Medicine, National Taiwan University, Taipei, Taiwan.
authors: Mei-Chuan
authors: MC
authors: Chen
authors: The Ph.D. program for Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan.
authors: Jing-Chi
authors: JC
authors: Wang
authors: School of Pharmacy, College of Pharmacy, Taipei, Taiwan.
authors: An-Chi
authors: AC
authors: Tsai
authors: Division of Medicinal Chemistry, College of Pharmacy, The Ohio State University, Columbus, Ohio.
authors: Ching-Shih
authors: CS
authors: Chen
authors: School of Pharmacy, College of Pharmacy, Taipei, Taiwan.
authors: Jing-Ping
authors: JP
authors: Liou
authors: The Ph.D. program for Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan.
authors: Shiow-Lin
authors: SL
authors: Pan
authors: Pharmacological Institute, College of Medicine, National Taiwan University, Taipei, Taiwan.
authors: Che-Ming
authors: CM
authors: Teng
mesh_terms: D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology*; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004195:Disease Models, Animal; D004357:Drug Synergism; D005260:Female; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology*; D006801:Humans; D006877:Hydroxamic Acids / Q000494:pharmacology*; D007211:Indoles / Q000494:pharmacology*; D008113:Liver Neoplasms / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology*; D009536:Niacinamide / Q000031:analogs & derivatives* / Q000494:pharmacology; D010671:Phenylurea Compounds / Q000494:pharmacology*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects; D000077157:Sorafenib; D047368:Tumor Burden / Q000187:drug effects; D023041:Xenograft Model Antitumor Assays
chemical_list: C577757:3-(1-benzenesulfonyl-2,3-dihydro-1H-indol-5-yl)-N-hydroxyacrylamide; D056572:Histone Deacetylase Inhibitors; D006877:Hydroxamic Acids; D007211:Indoles; D010671:Phenylurea Compounds; D047428:Protein Kinase Inhibitors; D009536:Niacinamide; D000077157:Sorafenib; D020169:Caspases