title: Molecular monitoring of epithelial-to-mesenchymal transition in breast cancer cells by means of Raman spectroscopy.
abstract: In breast cancer the presence of cells undergoing the epithelial-to-mesenchymal transition is indicative of metastasis progression. Since metabolic features of breast tumour cells are critical in cancer progression and drug resistance, we hypothesized that the lipid content of malignant cells might be a useful indirect measure of cancer progression. In this study Multivariate Curve Resolution was applied to cellular Raman spectra to assess the metabolic composition of breast cancer cells undergoing the epithelial to mesenchymal transition. Multivariate Curve Resolution analysis led to the conclusion that this transition affects the lipid profile of cells, increasing tryptophan but maintaining a low fatty acid content in comparison with highly metastatic cells. Supporting those results, a Partial Least Square-Discriminant analysis was performed to test the ability of Raman spectroscopy to discriminate the initial steps of epithelial to mesenchymal transition in breast cancer cells. We achieved a high level of sensitivity and specificity, 94% and 100%, respectively. In conclusion, Raman microspectroscopy coupled with Multivariate Curve Resolution enables deconvolution and tracking of the molecular content of cancer cells during a biochemical process, being a powerful, rapid, reagent-free and non-invasive tool for identifying metabolic features of breast cancer cell aggressiveness at first stages of malignancy.
authors.affiliation: ICFO-Institut de Ciències Fotòniques, Parc Mediterrani de la Tecnologia, Av Carl Friedrich Gauss, 3, 08860 Castelldefels, Barcelona, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Marro
authors.affiliation: ICFO-Institut de Ciències Fotòniques, Parc Mediterrani de la Tecnologia, Av Carl Friedrich Gauss, 3, 08860 Castelldefels, Barcelona, Spain; IDIBELL-Institut d'Investigació Biomèdica de Bellvitge, Av. Castelldefels, Km 2.7, 08907 L'Hospitalet de Llobregat, Barcelona, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Nieva
authors.affiliation: Unit of Biomarkers and Susceptibility, Catalan Institute of Oncology, IDIBELL, and CIBERESP, Barcelona, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Sanz-Pamplona
authors.affiliation: IDIBELL-Institut d'Investigació Biomèdica de Bellvitge, Av. Castelldefels, Km 2.7, 08907 L'Hospitalet de Llobregat, Barcelona, Spain. Electronic address: http://www.hospitalclinic.org/
authors.forename: A
authors.initials: A
authors.lastname: Sierra
mesh_terms: D000465:Algorithms; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D045744:Cell Line, Tumor; D016002:Discriminant Analysis; D058750:Epithelial-Mesenchymal Transition / Q000235:genetics; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D016018:Least-Squares Analysis; D010641:Phenotype; D013059:Spectrum Analysis, Raman / Q000379:methods*
keywords: Biomarker; Breast cancer; Epithelial-to-mesenchymal transition (EMT); Lipid; Metabolism; Raman spectroscopy