title: DJ-1 as a potential biomarker for the development of biocompatible multiwalled carbon nanotubes.
abstract: BACKGROUND
  In the present study, we investigated whether DJ-1 could serve as a biomarker for assessing the biocompatibility of multiwalled carbon nanotubes (MWCNTs), using the highly purified carbon nanotube, HTT2800.
  
  
  METHODS
  Using Western blot analysis, we determined DJ-1 protein levels in two different types of cells (one capable and the other incapable of HTT2800 endocytosis). Using quantitative real-time polymerase chain reaction, we also investigated the ability of purified nanotubes to alter DJ-1 mRNA levels.
  
  
  RESULTS
  We demonstrated that the DJ-1 protein concentration was reduced, regardless of the cytotoxic activity of intracellular HTT2800. Furthermore, HTT2800 decreased the DJ-1 mRNA levels in a dose-dependent manner. This decrease in DJ-1 mRNA levels was not observed in the case of Sumi black or cup-stacked carbon nanotubes.
  
  
  CONCLUSIONS
  These data indicate that modification of DJ-1 expression is caused by the cell response to MWCNTs. We conclude that DJ-1 is a promising candidate biomarker for the development of biocompatible MWCNTs.
authors: Institute of Carbon Science and Technology, Shinshu University, Matsumoto, Nagano, Japan. hhaniu@shinshu-u.ac.jp
authors: Hisao
authors: H
authors: Haniu
authors: Tamotsu
authors: T
authors: Tsukahara
authors: Yoshikazu
authors: Y
authors: Matsuda
authors: Yuki
authors: Y
authors: Usui
authors: Kaoru
authors: K
authors: Aoki
authors: Masayuki
authors: M
authors: Shimizu
authors: Nobuhide
authors: N
authors: Ogihara
authors: Kazuo
authors: K
authors: Hara
authors: Seiji
authors: S
authors: Takanashi
authors: Masanori
authors: M
authors: Okamoto
authors: Norio
authors: N
authors: Ishigaki
authors: Koichi
authors: K
authors: Nakamura
authors: Hiroyuki
authors: H
authors: Kato
authors: Naoto
authors: N
authors: Saito
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry* / Q000494:pharmacology; D015415:Biomarkers / Q000032:analysis; D045744:Cell Line, Tumor; D002470:Cell Survival; D015536:Down-Regulation / Q000187:drug effects; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000032:analysis* / Q000235:genetics / Q000378:metabolism; D008422:Materials Testing / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D015513:Oncogene Proteins / Q000032:analysis* / Q000235:genetics / Q000378:metabolism; D000071617:Protein Deglycase DJ-1; D012333:RNA, Messenger / Q000032:analysis; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D001672:Biocompatible Materials; D015415:Biomarkers; D047908:Intracellular Signaling Peptides and Proteins; D037742:Nanotubes, Carbon; D015513:Oncogene Proteins; D012333:RNA, Messenger; C105131:PARK7 protein, human; D000071617:Protein Deglycase DJ-1