Classification of agents using Syrian hamster embryo (SHE) cell transformation assay (CTA) with ATR-FTIR spectroscopy and multivariate analysis.
The Syrian hamster embryo (SHE) cell transformation assay (pH 6.7) has a reported sensitivity of 87% and specificity of 83%, and an overall concordance of 85% with in vivo rodent bioassay data. To date, the SHE assay is the only in vitro assay that exhibits multistage carcinogenicity. The assay uses morphological transformation, the first stage towards neoplasm, as an endpoint to predict the carcinogenic potential of a test agent. However, scoring of morphologically transformed SHE cells is subjective. We treated SHE cells grown on low-E reflective slides with 2,6-diaminotoluene, N-nitroso-N-ethylnitroguanidine, N-nitroso-N-methylurea, N-nitroso-N-ethylurea, EDTA, dimethyl sulphoxide (DMSO; vehicle control), methyl methanesulfonate, benzo[e]pyrene, mitomycin C, ethyl methanesulfonate, ampicillin or five different concentrations of benzo[a]pyrene. Macroscopically visible SHE colonies were located on the slides and interrogated using attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy acquiring five spectra per colony. The acquired IR data were analysed using Fisher's linear discriminant analysis (LDA) followed by principal component analysis (PCA)-LDA cluster vectors to extract major and minor discriminating wavenumbers for each treatment class. Each test agent vs. DMSO and treatment-induced transformed cells vs. corresponding non-transformed were classified by a unique combination of major and minor discriminating wavenumbers. Alterations associated with Amide I, Amide II, lipids and nucleic acids appear to be important in segregation of classes. Our findings suggest that a biophysical approach of ATR-FTIR spectroscopy with multivariate analysis could facilitate a more objective interrogation of SHE cells towards scoring for transformation and ultimately employing the assay for risk assessment of test agents.
Centre for Biophotonics, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK, BioReliance by SAFC, Medical Center Drive, Rockville, MD 20850, USA and Safety and Environmental Assurance Centre, Unilever Colworth Science Park, Bedfordshire, MK44 1LQ, UK.
Abdullah A
AA
Ahmadzai
Centre for Biophotonics, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK, BioReliance by SAFC, Medical Center Drive, Rockville, MD 20850, USA and Safety and Environmental Assurance Centre, Unilever Colworth Science Park, Bedfordshire, MK44 1LQ, UK.
Júlio
J
Trevisan
Centre for Biophotonics, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK, BioReliance by SAFC, Medical Center Drive, Rockville, MD 20850, USA and Safety and Environmental Assurance Centre, Unilever Colworth Science Park, Bedfordshire, MK44 1LQ, UK.
Weiyi
W
Pang
Centre for Biophotonics, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK, BioReliance by SAFC, Medical Center Drive, Rockville, MD 20850, USA and Safety and Environmental Assurance Centre, Unilever Colworth Science Park, Bedfordshire, MK44 1LQ, UK.
Matthew J
MJ
Riding
Centre for Biophotonics, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK, BioReliance by SAFC, Medical Center Drive, Rockville, MD 20850, USA and Safety and Environmental Assurance Centre, Unilever Colworth Science Park, Bedfordshire, MK44 1LQ, UK.
Rebecca J
RJ
Strong
Centre for Biophotonics, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK, BioReliance by SAFC, Medical Center Drive, Rockville, MD 20850, USA and Safety and Environmental Assurance Centre, Unilever Colworth Science Park, Bedfordshire, MK44 1LQ, UK.
Valon
V
Llabjani
BioReliance by SAFC, Medical Center Drive, Rockville, MD 20850, USA and.
Kamala
K
Pant
Safety and Environmental Assurance Centre, Unilever Colworth Science Park, Bedfordshire, MK44 1LQ, UK.
Paul L
PL
Carmichael
Safety and Environmental Assurance Centre, Unilever Colworth Science Park, Bedfordshire, MK44 1LQ, UK.
Andrew D
AD
Scott
Centre for Biophotonics, Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK, BioReliance by SAFC, Medical Center Drive, Rockville, MD 20850, USA and Safety and Environmental Assurance Centre, Unilever Colworth Science Park, Bedfordshire, MK44 1LQ, UK f.martin@lancaster.ac.uk.
Francis L
FL
Martin
D000818:Animals; D015197:Carcinogenicity Tests / Q000379:methods*; D002273:Carcinogens / Q000145:classification / Q000633:toxicity*; D002471:Cell Transformation, Neoplastic; D004622:Embryo, Mammalian / Q000187:drug effects / Q000473:pathology; D008647:Mesocricetus; D015999:Multivariate Analysis; D025341:Principal Component Analysis; D017550:Spectroscopy, Fourier Transform Infrared
D002273:Carcinogens