title: Differential protein expression of peroxiredoxin I and II by benzo(a)pyrene and quercetin treatment in 22Rv1 and PrEC prostate cell lines.
abstract: Mechanisms of benzo(a)pyrene (BaP)-mediated toxicity and chemopreventative potential of quercetin in prostate cancer are poorly understood. Two-dimensional gel electrophoresis was used to map the differences in protein expression in BaP (1 microM)- and quercetin (5 microM)-treated 22Rv1 human prostate cancer cells. As compared to DMSO, 26 proteins in BaP and 41 proteins in quercetin were found to be differentially expressed (+/-2-fold). Western blots confirmed that BaP increased peroxiredoxin (Prx) Prx I and decreased Prx II in 22Rv1 cells. Similar results were found in PrEC normal prostate epithelial cells. Quercetin (up to 10 microM) upregulated Prx II without altering Prx I levels in 22Rv1 cells whereas in PrEC cells, it did not alter the constitutive protein expression of Prx I or II. The lack of quercetin-mediated changes in Prx expression suggests that quercetin does not interfere with H(2)O(2) levels, and thus may have no deleterious effect in normal prostate cells. Quercetin inhibited both BaP-mediated effects on Prx I and II in 22Rv1 cells. In PrEC cells, quercetin inhibited BaP-mediated upregulation of Prx I and had tendency to neutralize BaP-mediated downregulation of Prx II. Quercetin also inhibited BaP-induced concentrations of reactive oxygen species in both 22Rv1 and PrEC cells. These results suggest that Prx I and II may be involved in BaP-mediated toxicity and the potential chemopreventative mechanisms of quercetin.
authors.affiliation: Department of Pharmacology and Environmental Toxicology Research Program, School of Pharmacy, The University of Mississippi, 315 Faser Hall, Box 1848, University, MS 38677, USA.
authors.forename: Amit
authors.initials: A
authors.lastname: Chaudhary
authors.forename: Tibor
authors.initials: T
authors.lastname: Pechan
authors.forename: Kristine L
authors.initials: KL
authors.lastname: Willett
mesh_terms: D001564:Benzo(a)pyrene / Q000494:pharmacology*; D015153:Blotting, Western; D002460:Cell Line; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D004591:Electrophoresis, Polyacrylamide Gel; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007202:Indicators and Reagents; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects / Q000502:physiology; D010544:Peroxidases / Q000096:biosynthesis*; D054464:Peroxiredoxins; D011467:Prostate / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology; D011794:Quercetin / Q000494:pharmacology*; D017382:Reactive Oxygen Species; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D007202:Indicators and Reagents; D017382:Reactive Oxygen Species; D001564:Benzo(a)pyrene; D011794:Quercetin; D010544:Peroxidases; D054464:Peroxiredoxins