title: Identification of chemoresistant factors by protein expression analysis with iTRAQ for head and neck carcinoma.
abstract: BACKGROUND
  Cisplatin and other anticancer drugs are important in the treatment of head and neck squamous cell carcinoma; however, some tumours develop drug resistance. If chemoresistance could be determined before treatment, unnecessary drug administration would be avoided. Here, we investigated chemoresistance factors by comprehensive analyses at the protein level.
  
  
  METHODS
  Four human carcinoma cell lines were used: cisplatin-sensitive UM-SCC-23, UM-SCC-23-CDDPR with acquired cisplatin resistance, naturally cisplatin-resistant UM-SCC-81B, and UM-SCC-23/WR with acquired 5-fluorouracil resistance. Extracted proteins were labelled with iTRAQ and analysed by tandem mass spectrometry to identify resistance. Protein expression was confirmed by western blotting and functional analysis was carried out using siRNA.
  
  
  RESULTS
  Thirteen multiple-drug resistance proteins were identified, as well as seven proteins with specific resistance to cisplatin, including α-enolase. Differential expression of these proteins in cisplatin-resistant and -sensitive cell lines was confirmed by western blotting. Functional analysis for α-enolase by siRNA showed that cisplatin sensitivity significantly was increased in UM-SCC-81B and slightly in UM-SCC-23-CDDPR but not in UM-SCC-23/WR cells.
  
  
  CONCLUSIONS
  We identified proteins thought to mediate anticancer drug resistance using recent proteome technology and identified α-enolase as a true cisplatin chemoresistance factor. Such proteins could be used as biomarkers for anticancer agent resistance and as targets of cancer therapy.
authors.affiliation: Department of Otorhinolaryngology, Aichi Medical University School of Medicine, 1-1 Yazakokarimata, Nagakute, Aichi 480-1195, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Nishimura
authors.affiliation: Department of Otorhinolaryngology, Aichi Medical University School of Medicine, 1-1 Yazakokarimata, Nagakute, Aichi 480-1195, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Tsuchiya
authors.affiliation: Department of Otorhinolaryngology, Aichi Medical University School of Medicine, 1-1 Yazakokarimata, Nagakute, Aichi 480-1195, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Okamoto
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Nagoya City University Graduate School of Medical Science, 1-1 Yazakokarimata, Nagakute, Aichi 480-1195, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Ijichi
authors.affiliation: Unit of Biostatistics, Advanced Medical Research Center, Aichi Medical University School of Medicine, 1-1 Yazakokarimata, Nagakute, Aichi 480-1195, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Gosho
authors.affiliation: Division of Clinical Research Promotion, Institute of Comprehensive Medical Research, Aichi Medical University School of Medicine, 1-1 Yazakokarimata, Nagakute, Aichi 480-1195, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Fukayama
authors.affiliation: Division of Clinical Research Promotion, Institute of Comprehensive Medical Research, Aichi Medical University School of Medicine, 1-1 Yazakokarimata, Nagakute, Aichi 480-1195, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yoshikawa
authors.affiliation: Department of Otorhinolaryngology, Aichi Medical University School of Medicine, 1-1 Yazakokarimata, Nagakute, Aichi 480-1195, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Ueda
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Taubman Center Floor 1 Reception A, 1500 E Medical Center Drive SPC 5312, Ann Arbor, MI 48109, USA.
authors.forename: C R
authors.initials: CR
authors.lastname: Bradford
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Michigan, Taubman Center Floor 1 Reception A, 1500 E Medical Center Drive SPC 5312, Ann Arbor, MI 48109, USA.
authors.forename: T E
authors.initials: TE
authors.lastname: Carey
authors.affiliation: Department of Otorhinolaryngology, Aichi Medical University School of Medicine, 1-1 Yazakokarimata, Nagakute, Aichi 480-1195, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ogawa
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000378:metabolism*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002945:Cisplatin / Q000494:pharmacology*; D019008:Drug Resistance, Neoplasm; D005472:Fluorouracil / Q000494:pharmacology*; D055785:Gene Knockdown Techniques; D006258:Head and Neck Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D006801:Humans; D010751:Phosphopyruvate Hydratase / Q000235:genetics / Q000378:metabolism; D020543:Proteome / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics; D051881:Receptor, Notch1 / Q000378:metabolism; D000077195:Squamous Cell Carcinoma of Head and Neck; D013194:Staining and Labeling; D053719:Tandem Mass Spectrometry
chemical_list: D000970:Antineoplastic Agents; C497761:NOTCH1 protein, human; D020543:Proteome; D034741:RNA, Small Interfering; D051881:Receptor, Notch1; D010751:Phosphopyruvate Hydratase; D002945:Cisplatin; D005472:Fluorouracil