title: Protein identification from dried nipple aspirate fluid on Guthrie cards using mass spectrometry.
abstract: Nipple aspirate fluid (NAF) requires investigation as a potential source of biomarkers for early diagnosis or risk assessment in breast cancer and other breast disorders. The present study demonstrated that proteins were easily extracted from dried NAF spots on Guthrie cards and were suitable for mass spectrometry analysis. NAF was obtained from 80 women, collected on Guthrie cards, between 2007 and 2010. The NAF-proteins were extracted from the card by incubating the card in water. These proteins were then quantified and separated using one-dimensional, 12% SDS-PAGE, gel electrophoresis and on high-resolution gradient gels at different concentrations (4-12, 8-16 and 4-20%). The bands with the most abundant proteins were excised from the gradient gels and the proteins were identified by liquid chromatography quadrupole time of flight. Immunoglobulins, Zn-α2-glicoprotein, apoliprotein D and prolactin inducible protein were among those identified. The NAF-Guthrie card collection method has not been applied previously, however, NAF proteins have been identified using other collecting techniques, confirming the feasibility of the NAF Guthrie card collection method for analyzing the proteins within NAF. The NAF-Guthrie card collecting method has multiple advantages, including being inexpensive, non-invasive, reliable and painless, and the cards can be stored at room temperature. Examining NAF may assist in identifying individuals at a higher risk of breast cancer and in improving patient prognosis.
authors.affiliation: Applied Genetics Laboratory, Haematology Service, National Cancer Institute, Rio de Janeiro, 20230-130, Brazil.
authors.forename: Lucas
authors.initials: L
authors.lastname: Delmonico
authors.affiliation: Applied Genetics Laboratory, Haematology Service, National Cancer Institute, Rio de Janeiro, 20230-130, Brazil.
authors.forename: Vivian Rabello
authors.initials: VR
authors.lastname: Areias
authors.affiliation: Applied Genetics Laboratory, Haematology Service, National Cancer Institute, Rio de Janeiro, 20230-130, Brazil.
authors.forename: Rodrigo César
authors.initials: RC
authors.lastname: Pinto
authors.affiliation: Applied Genetics Laboratory, Haematology Service, National Cancer Institute, Rio de Janeiro, 20230-130, Brazil.
authors.forename: Cintia Da Silva
authors.initials: Cda S
authors.lastname: Matos
authors.affiliation: Radiology Service, Gaffrée e Guinle University Hospital, Rio de Janeiro, 20270-004, Brazil.
authors.forename: Marco Felipe Franco
authors.initials: MF
authors.lastname: Rosa
authors.affiliation: Radiology Service, Gaffrée e Guinle University Hospital, Rio de Janeiro, 20270-004, Brazil.
authors.forename: Carolina Maria
authors.initials: CM
authors.lastname: De Azevedo
authors.affiliation: Applied Genetics Laboratory, Haematology Service, National Cancer Institute, Rio de Janeiro, 20230-130, Brazil.
authors.forename: Gilda
authors.initials: G
authors.lastname: Alves
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000302:isolation & purification* / Q000378:metabolism; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000517:prevention & control; D002853:Chromatography, Liquid; D042241:Early Diagnosis; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006801:Humans; D042361:Mammary Glands, Human / Q000378:metabolism / Q000502:physiology / Q000503:physiopathology; D013058:Mass Spectrometry; D008875:Middle Aged; D058977:Molecular Sequence Annotation; D055966:Nipple Aspirate Fluid / Q000737:chemistry*; D011506:Proteins / Q000302:isolation & purification* / Q000378:metabolism; D011934:Reagent Strips; D052616:Solid Phase Extraction / Q000379:methods; D014867:Water
chemical_list: D014408:Biomarkers, Tumor; D011506:Proteins; D011934:Reagent Strips; D014867:Water