title: Global liver proteomics of rats exposed for 5 days to phenobarbital identifies changes associated with cancer and with CYP metabolism.
abstract: A global proteomics approach was applied to model the hepatic response elicited by the toxicologically well-characterized xenobiotic phenobarbital (PB), a prototypical inducer of hepatic xenobiotic metabolizing enzymes and a well-known nongenotoxic liver carcinogen in rats. Differential detergent fractionation two-dimensional liquid chromatography electrospray ionization tandem mass spectrometry and systems biology modeling were used to identify alterations in toxicologically relevant hepatic molecular functions and biological processes in the livers of rats following a 5-day exposure to PB at 80 mg/kg/day or a vehicle control. Of the 3342 proteins identified, expression of 121 (3.6% of the total proteins) was significantly increased and 127 (3.8%) significantly decreased in the PB group compared to controls. The greatest increase was seen for cytochrome P450 (CYP) 2B2 (167-fold). All proteins with statistically significant differences from control were then analyzed using both Gene Ontology (GO) and Ingenuity Pathways Analysis (IPA, 5.0 IPA-Tox) for cellular location, function, network connectivity, and possible disease processes, especially as they relate to CYP-mediated metabolism and nongenotoxic carcinogenesis mechanisms. The GO results suggested that PB's mechanism of nongenotoxic carcinogenesis involves both increased xenobiotic metabolism, especially induction of the 2B subfamily of CYP enzymes, and increased cell cycle activity. Apoptosis, however, also increased, perhaps, as an attempt to counter the rising cancer threat. Of the IPA-mapped proteins, 41 have functions which are procarcinogenic and 14 anticarcinogenic according to the hypothesized nongenotoxic mechanism of imbalance between apoptosis and cellular proliferation. Twenty-two additional IPA nodes can be classified as procarcinogenic by the competing theory of increased metabolism resulting in the formation of reactive oxygen species. Since the systems biology modeling corresponded well to PB effects previously elucidated via more traditional methods, the global proteomic approach is proposed as a new screening methodology that can be incorporated into future toxicological studies.
authors.affiliation: Center for Environmental Health Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, Mississippi 39762, USA.
authors.forename: Mary B
authors.initials: MB
authors.lastname: Dail
authors.forename: L Allen
authors.initials: LA
authors.lastname: Shack
authors.forename: Janice E
authors.initials: JE
authors.lastname: Chambers
authors.forename: Shane C
authors.initials: SC
authors.lastname: Burgess
mesh_terms: D000818:Animals; D002853:Chromatography, Liquid; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D008099:Liver / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D008114:Liver Neoplasms, Experimental / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D010634:Phenobarbital / Q000494:pharmacology*; D040901:Proteomics; D051381:Rats; D017207:Rats, Sprague-Dawley; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D003577:Cytochrome P-450 Enzyme System; D010634:Phenobarbital
references.citation: BMC Mol Biol. 2007 Apr 12;8:27
references.pmid: 17430600
references.citation: FEBS Lett. 2005 Dec 19;579(30):6733-6
references.pmid: 16310787
references.citation: Cell Death Differ. 2005 May;12(5):512-22
references.pmid: 15933726
references.citation: Proteomics. 2006 May;6(9):2759-71
references.pmid: 16596704
references.citation: J Cell Biol. 1995 Aug;130(3):507-18
references.pmid: 7542657
references.citation: Pharmacol Toxicol. 2001 Sep;89(3):113-22
references.pmid: 11589781
references.citation: FASEB J. 2008 Jan;22(1):74-83
references.pmid: 17720800
references.citation: J Biol Chem. 2007 Sep 21;282(38):28226-36
references.pmid: 17644513
references.citation: Toxicol Sci. 2002 Jun;67(2):232-40
references.pmid: 12011482
references.citation: Nat Methods. 2007 Mar;4(3):207-14
references.pmid: 17327847
references.citation: Electrophoresis. 1994 Feb;15(2):265-77
references.pmid: 8026443
references.citation: Mol Pharmacol. 2002 Jan;61(1):1-6
references.pmid: 11752199
references.citation: Drug Metab Dispos. 2003 Apr;31(4):351-5
references.pmid: 12642458
references.citation: Hepatology. 2002 Jul;36(1):195-201
references.pmid: 12085365
references.citation: Virology. 2007 May 25;362(1):16-25
references.pmid: 17257639
references.citation: J Proteome Res. 2005 Mar-Apr;4(2):316-24
references.pmid: 15822906
references.citation: Plant Physiol. 2007 Aug;144(4):1697-714
references.pmid: 17556508
references.citation: Biochem Biophys Res Commun. 2000 Jan 7;267(1):221-7
references.pmid: 10623602
references.citation: J Biochem Toxicol. 1995 Apr;10(2):63-8
references.pmid: 7562954
references.citation: BMC Genomics. 2006 Sep 08;7:229
references.pmid: 16961921
references.citation: Biochem J. 1992 Feb 1;281 ( Pt 3):577-92
references.pmid: 1536639
references.citation: Exp Cell Res. 2007 Jan 1;313(1):179-94
references.pmid: 17112511
references.citation: Proteomics. 2006 Aug;6(16):4662-70
references.pmid: 16897686
references.citation: Mol Pharmacol. 2007 Dec;72(6):1419-24
references.pmid: 17898314
references.citation: Biochem Biophys Res Commun. 1998 Feb 13;243(2):531-7
references.pmid: 9480843
references.citation: J Cell Sci. 2005 Aug 15;118(Pt 16):3569-72
references.pmid: 16105880
references.citation: Nucleic Acids Res. 2005 Jan 1;33(Database issue):D471-5
references.pmid: 15608240
references.citation: J Biol Chem. 2006 Aug 4;281(31):21878-21883
references.pmid: 16762922
references.citation: Cytogenet Genome Res. 2007;117(1-4):278-87
references.pmid: 17675869
references.citation: Mol Cell Proteomics. 2004 May;3(5):441-55
references.pmid: 14739257
references.citation: Proteomics. 2007 Jul;7(14):2479-88
references.pmid: 17623305
references.citation: Genomics. 2006 Nov;88(5):669-72
references.pmid: 16934433
references.citation: Nucleic Acids Res. 2007 Jan;35(Database issue):D658-62
references.pmid: 17151068
references.citation: Nat Genet. 2000 May;25(1):25-9
references.pmid: 10802651
references.citation: Biochim Biophys Acta. 2003 Feb 17;1619(3):239-42
references.pmid: 12573483
references.citation: Anal Chem. 2002 Nov 1;74(21):5593-9
references.pmid: 12433093
references.citation: Arch Biochem Biophys. 2005 Mar 1;435(1):125-33
references.pmid: 15680914
references.citation: J Biol Chem. 2001 May 25;276(21):17754-61
references.pmid: 11278304
references.citation: Vaccine. 2007 Jan 15;25(5):932-8
references.pmid: 17027125
references.citation: J Biosci Bioeng. 2006 Jun;101(6):501-7
references.pmid: 16935252
references.citation: Cell. 2006 Oct 6;127(1):45-8
references.pmid: 17018275
references.citation: Physiol Genomics. 2001 Apr 27;5(4):161-70
references.pmid: 11328961
references.citation: Mol Cell Biol. 1999 Mar;19(3):1720-30
references.pmid: 10022859
references.citation: J Biol Chem. 1999 Feb 26;274(9):5259-62
references.pmid: 10026130
references.citation: Mol Pharmacol. 2000 Aug;58(2):279-87
references.pmid: 10908295
references.citation: Nature. 1997 Feb 6;385(6616):540-4
references.pmid: 9020361
references.citation: Genomics. 1995 Jul 20;28(2):350-3
references.pmid: 8530050
references.citation: Cell. 2007 Jul 13;130(1):77-88
references.pmid: 17632057
references.citation: Drug Metab Dispos. 2004 Apr;32(4):382-6
references.pmid: 15039290
references.citation: Proteomics. 2007 Apr;7(8):1316-26
references.pmid: 17443643
references.citation: Mol Carcinog. 2006 Dec;45(12):914-33
references.pmid: 16921489
references.citation: Chem Res Toxicol. 2007 Apr;20(4):600-8
references.pmid: 17381134
references.citation: Proc Natl Acad Sci U S A. 2005 Jan 25;102(4):1110-5
references.pmid: 15650050
references.citation: Toxicol Sci. 2007 Sep;99(1):35-42
references.pmid: 17517822
references.citation: Toxicology. 2000 Apr 20;146(1):15-22
references.pmid: 10773359
references.citation: Cancer Cell. 2007 Sep;12(3):230-8
references.pmid: 17785204
references.citation: Nat Biotechnol. 1999 Jul;17(7):676-82
references.pmid: 10404161
references.citation: Cell Signal. 2007 May;19(5):892-901
references.pmid: 17336499
references.citation: Mol Reprod Dev. 2006 Jun;73(6):767-73
references.pmid: 16541461
references.citation: Clin Chem. 2005 Oct;51(10):1796-803
references.pmid: 16099942
references.citation: Proteomics. 2005 Dec;5(18):4852-63
references.pmid: 16247735
references.citation: Anal Chem. 2003 Sep 1;75(17):4646-58
references.pmid: 14632076
references.citation: J Biol Chem. 2003 Sep 12;278(37):35184-92
references.pmid: 12840027
references.citation: J Biol Chem. 1999 Dec 10;274(50):35461-8
references.pmid: 10585417
references.citation: J Cell Physiol. 2001 Dec;189(3):334-40
references.pmid: 11748591
references.citation: Genome Biol. 2005;6(1):R9
references.pmid: 15642101
references.citation: FASEB J. 2004 Feb;18(2):379-81
references.pmid: 14657004
references.citation: Toxicol Pathol. 2005;33(1):118-26
references.pmid: 15805063
references.citation: Mutat Res. 2004 May 18;549(1-2):101-13
references.pmid: 15120965
references.citation: BMC Bioinformatics. 2007 Nov 01;8 Suppl 7:S24
references.pmid: 18047724
references.citation: Development. 2002 Apr;129(7):1705-14
references.pmid: 11923206
references.citation: Arch Toxicol. 2004 Aug;78(8):435-42
references.pmid: 15107969
references.citation: Steroids. 2007 Mar;72(3):231-46
references.pmid: 17284330
references.citation: Mutat Res. 2004 Sep 12;563(1):1-11
references.pmid: 15324744
references.citation: Biol Cell. 2004 Aug;96(6):407-11
references.pmid: 15384226
references.citation: Cancer Res. 1999 Jun 15;59(12):2981-8
references.pmid: 10383164
references.citation: Int J Toxicol. 2006 Jan-Feb;25(1):57-64
references.pmid: 16510358
references.citation: Biochem Pharmacol. 2002 Apr 15;63(8):1397-404
references.pmid: 11996880
references.citation: Pharmacol Toxicol. 2002 Jul;91(1):1-7
references.pmid: 12193254