title: Responses of A549 human lung epithelial cells to cristobalite and α-quartz exposures assessed by toxicoproteomics and gene expression analysis.
abstract: In this study, we used cytotoxicity assays, proteomic and gene expression analyses to examine the difference in response of A549 cells to two silica particles that differ in physical properties, namely cristobalite (CR) and α-quartz (Min-U-Sil 5, MI). Cytotoxicity assays such as lactate dehydrogenase release, 5-bromo-2'-deoxyuridine incorporation and cellular ATP showed that both silica particles could cause cell death, decreased cell proliferation and metabolism in the A549 human lung epithelial cells. While cytotoxicity assays revealed little difference between CR and MI exposures, proteomic and gene expression analyses unveiled both similar and unique molecular changes in A549 cells. For instance, two-dimensional gel electrophoresis data indicated that the expression of proteins in the cell death (e.g., ALDH1A1, HTRA2 and PRDX6) and cell proliferation (e.g., FSCN1, HNRNPAB and PGK1) pathways were significantly different between the two silica particles. Reverse transcription-polymerase chain reaction data provided additional evidence supporting the proteomic findings. Preliminary assessment of the physical differences between CR and MI suggested that the extent of surface interaction between particles and cells could explain some of the observed biological effects. However, the differential dose-response curves for some other genes and proteins suggest that other physical attributes of particulate matter can also contribute to particulate matter-related cellular toxicity. Our results demonstrated that toxicoproteomic and gene expression analyses are sensitive in distinguishing subtle toxicity differences associated with silica particles of varying physical properties compared to traditional cytotoxicity endpoints. Copyright © 2016 Her Majesty the Queen in Right of Canada. Journal of Applied Toxicology published by John Wiley & Sons, Ltd.
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, K1A 0K9, Canada.|Department of Biochemistry, Faculty of Science, University of Ottawa, Ottawa, ON, K1H 8M5, Canada.
authors.forename: Ngoc Q
authors.initials: NQ
authors.lastname: Vuong
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, K1A 0K9, Canada.
authors.forename: Patrick
authors.initials: P
authors.lastname: Goegan
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, K1A 0K9, Canada.
authors.forename: Francesco
authors.initials: F
authors.lastname: De Rose
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, K1A 0K9, Canada.
authors.forename: Dalibor
authors.initials: D
authors.lastname: Breznan
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, K1A 0K9, Canada.
authors.forename: Errol M
authors.initials: EM
authors.lastname: Thomson
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, K1A 0K9, Canada.
authors.forename: Julie S
authors.initials: JS
authors.lastname: O'Brien
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, K1A 0K9, Canada.
authors.forename: Subramanian
authors.initials: S
authors.lastname: Karthikeyan
authors.affiliation: Biostatistics Section, Population Studies Division, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, K1A 0K9, Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Williams
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, K1A 0K9, Canada.|Department of Biochemistry, Faculty of Science, University of Ottawa, Ottawa, ON, K1H 8M5, Canada.
authors.forename: Renaud
authors.initials: R
authors.lastname: Vincent
authors.affiliation: Analytical Biochemistry and Proteomics Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, K1A 0K9, Canada.
authors.forename: Premkumari
authors.initials: P
authors.lastname: Kumarathasan
mesh_terms: D000072283:A549 Cells; D018929:Cell Culture Techniques; D002470:Cell Survival / Q000187:drug effects; D015180:Electrophoresis, Gel, Two-Dimensional; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism; D020869:Gene Expression Profiling / Q000379:methods; D006801:Humans; D052638:Particulate Matter / Q000737:chemistry / Q000633:toxicity*; D020543:Proteome / Q000187:drug effects*; D040901:Proteomics / Q000379:methods; D011791:Quartz / Q000737:chemistry / Q000633:toxicity; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide / Q000737:chemistry / Q000633:toxicity*; D013499:Surface Properties; D059467:Transcriptome / Q000187:drug effects*
chemical_list: D052638:Particulate Matter; D020543:Proteome; D011791:Quartz; D012822:Silicon Dioxide
keywords: 2D-GE: two-dimensional gel electrophoresis; A549 cells; RT-PCR; cristobalite; cytotoxicity; genomics; proteomics; silica; α-quartz