title: Combination treatment of renal cell carcinoma with belinostat and 5-fluorouracil: a role for oxidative stress induced DNA damage and HSP90 regulated thymidine synthase.
abstract: OBJECTIVE
  Despite several therapeutic options renal cell carcinoma is associated with a poor clinical outcome. Therefore, we investigated whether combining 5-fluorouracil with the histone deacetylase inhibitor belinostat would exert a synergistic effect on renal cell carcinoma cells in vitro and in vivo.
  
  
  METHODS
  We used SN12C cells treated with 5-fluorouracil and/or belinostat in vitro and in xenograft experiments in vivo. Cell viability and death mechanisms were assessed by MTS assay and Western blot. To investigate the role of reactive oxygen species we used H2DCF-DA, reactive oxygen species scavengers and the roGFP2 construct.
  
  
  RESULTS
  Belinostat potentiated the anticancer effect of 5-fluorouracil. It synergistically induced apoptosis by activating caspases and increasing the subG1 cell population. Effects on reactive oxygen species mediated DNA damage included decreased thioredoxin expression and increased levels of TBP-2, γ-H2AX and Ac-H3. Furthermore, belinostat attenuated the 5-fluorouracil mediated induction of thymidylate synthase via HSP90 hyperacetylation. Co-administration of 5-fluorouracil with belinostat similarly reduced tumor volume and weight, and increased γ-H2AX and Ac-H3 levels in the SN12C xenograft model.
  
  
  CONCLUSIONS
  In combination with 5-fluorouracil the targeted inhibitor of histone deacetylase synergistically inhibited renal cancer cell growth by the blockade of thymidylate synthase induction and the induction of reactive oxygen species mediated DNA damage in vitro and in vivo. Our results suggest that combined treatment with belinostat and 5-fluorouracil may represent a promising new approach to renal cancer.
authors.affiliation: Institute for Innovative Cancer Research, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
authors.forename: Mi Joung
authors.initials: MJ
authors.lastname: Kim
authors.affiliation: Institute for Innovative Cancer Research, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
authors.forename: Jee Suk
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Institute for Innovative Cancer Research, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea; Department of Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
authors.forename: Sang Eun
authors.initials: SE
authors.lastname: Park
authors.affiliation: Institute for Innovative Cancer Research, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
authors.forename: Hye-Jin
authors.initials: HJ
authors.lastname: Yi
authors.affiliation: Institute for Innovative Cancer Research, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea; Department of Urology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
authors.forename: In Gab
authors.initials: IG
authors.lastname: Jeong
authors.affiliation: Bio-Evaluation Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea.
authors.forename: Jong Soon
authors.initials: JS
authors.lastname: Kang
authors.affiliation: Bio-Evaluation Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, Republic of Korea.
authors.forename: Jieun
authors.initials: J
authors.lastname: Yun
authors.affiliation: Department of Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea; Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
authors.forename: Joo-Yong
authors.initials: JY
authors.lastname: Lee
authors.affiliation: CrystalGenomics, Inc., Gyeonggi-Do, Republic of Korea.
authors.forename: Seonggu
authors.initials: S
authors.lastname: Ro
authors.affiliation: Institute for Innovative Cancer Research, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea; Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
authors.forename: Jung Shin
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Institute for Innovative Cancer Research, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea; Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea; Center for Development and Commercialization of Anti-Cancer Therapeutics, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
authors.forename: Eun Kyung
authors.initials: EK
authors.lastname: Choi
authors.affiliation: Institute for Innovative Cancer Research, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea; Department of Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea; Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea. Electronic address: jjhwang@amc.seoul.kr.
authors.forename: Jung Jin
authors.initials: JJ
authors.lastname: Hwang
authors.affiliation: Institute for Innovative Cancer Research, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea; Department of Urology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea. Electronic address: cskim@amc.seoul.kr.
authors.forename: Choung-Soo
authors.initials: CS
authors.lastname: Kim
mesh_terms: D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000008:administration & dosage*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage*; D002292:Carcinoma, Renal Cell / Q000188:drug therapy* / Q000378:metabolism*; D004249:DNA Damage / Q000187:drug effects*; D004359:Drug Therapy, Combination; D005472:Fluorouracil / Q000008:administration & dosage*; D018841:HSP90 Heat-Shock Proteins / Q000187:drug effects*; D056572:Histone Deacetylase Inhibitors / Q000008:administration & dosage*; D006801:Humans; D006877:Hydroxamic Acids / Q000008:administration & dosage*; D007680:Kidney Neoplasms / Q000188:drug therapy* / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D019001:Nitric Oxide Synthase; D018384:Oxidative Stress / Q000187:drug effects*; D013449:Sulfonamides / Q000008:administration & dosage*; D013940:Thymidylate Synthase / Q000187:drug effects*; D014407:Tumor Cells, Cultured
chemical_list: D000964:Antimetabolites, Antineoplastic; D018841:HSP90 Heat-Shock Proteins; D056572:Histone Deacetylase Inhibitors; D006877:Hydroxamic Acids; D013449:Sulfonamides; D019001:Nitric Oxide Synthase; D013940:Thymidylate Synthase; C487081:belinostat; D005472:Fluorouracil
keywords: belinostat; carcinoma; combination; drug therapy; fluorouracil; kidney; renal cell