title: Identification of toxicological biomarkers of di(2-ethylhexyl) phthalate in proteins secreted by HepG2 cells using proteomic analysis.
abstract: The effects of di(2-ethylhexyl) phthalate (DEHP) on proteins secreted by HepG2 cells were studied using a proteomic approach. HepG2 cells were exposed to various concentrations of DEHP (0, 2.5, 5, 10, 25, 50, 100, and 250 microM) for 24 or 48 h. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and comet assays were then conducted to determine the cytotoxicity and genotoxicity of DEHP, respectively. The MTT assay showed that 10 microM DEHP was the maximum concentration that did not cause cell death. In addition, the DNA damage in HepG2 cells exposed to DEHP was found to increase in a dose- and time-dependent fashion. Proteomic analysis using two different pI ranges (4-7 and 6-9) and large size 2-DE revealed the presence of 2776 protein spots. A total of 35 (19 up- and 16 down-regulated) proteins were identified as biomarkers of DEHP by ESI-MS/MS. Several differentiated protein groups were also found. Proteins involved in apoptosis, transportation, signaling, energy metabolism, and cell structure and motility were found to be up- or down-regulated. Among these, the identities of cystatin C, Rho GDP inhibitor, retinol binding protein 4, gelsolin, DEK protein, Raf kinase inhibitory protein, triose phosphate isomerase, cofilin-1, and haptoglobin-related protein were confirmed by Western blot assay. Therefore, these proteins could be used as potential biomarkers of DEHP and human disease associated with DEHP.
authors.affiliation: Graduate School of Medicine, Korea University, Sungbuk-Ku, Seoul, Republic of Korea.
authors.forename: Seonyoung
authors.initials: S
authors.lastname: Choi
authors.forename: So-Young
authors.initials: SY
authors.lastname: Park
authors.forename: Ji
authors.initials: J
authors.lastname: Jeong
authors.forename: Eunkyung
authors.initials: E
authors.lastname: Cho
authors.forename: Sohee
authors.initials: S
authors.lastname: Phark
authors.forename: Min
authors.initials: M
authors.lastname: Lee
authors.forename: Dongsub
authors.initials: D
authors.lastname: Kwak
authors.forename: Ji-Youn
authors.initials: JY
authors.lastname: Lim
authors.forename: Woon-Won
authors.initials: WW
authors.lastname: Jung
authors.forename: Donggeun
authors.initials: D
authors.lastname: Sul
mesh_terms: D015415:Biomarkers / Q000032:analysis; D049109:Cell Proliferation / Q000187:drug effects; D004249:DNA Damage; D004051:Diethylhexyl Phthalate / Q000494:pharmacology*; D015536:Down-Regulation; D056945:Hep G2 Cells; D006801:Humans; D020543:Proteome / Q000032:analysis*; D040901:Proteomics; D015854:Up-Regulation
chemical_list: D015415:Biomarkers; D020543:Proteome; D004051:Diethylhexyl Phthalate