title: Label-free proteomic analysis of breast cancer molecular subtypes.
abstract: To better characterize the cellular pathways involved in breast cancer molecular subtypes, we performed a proteomic study using a label-free LC-MS strategy for determining the proteomic profile of Luminal A, Luminal-HER2, HER2-positive, and triple-negative (TN) breast tumors compared with healthy mammary tissue. This comparison aimed to identify the aberrant processes specific for each subtype and might help to refine our understanding regarding breast cancer biology. Our results address important molecular features (both specific and commonly shared) that explain the biological behavior of each subtype. Changes in proteins related to cytoskeletal organization were found in all tumor subtypes, indicating that breast tumors are under constant structural modifications to invade and metastasize. We also found changes in cell-adhesion processes in all molecular subtypes, corroborating that invasiveness is a common property of breast cancer cells. Luminal-HER2 and HER2 tumors also presented altered cell cycle regulation, as shown by the several DNA repair-related proteins. An altered immune response was also found as a common process in the Luminal A, Luminal-HER2, and TN subtypes, and complement was the most important pathway. Analysis of the TN subtype revealed blood coagulation as the most relevant biological process.
authors.affiliation: Laboratório de Células Tronco, Instituto Nacional do Câncer, INCA , Rio de Janeiro, Brazil.
authors.forename: Carolina
authors.initials: C
authors.lastname: Panis
authors.forename: Luciana
authors.initials: L
authors.lastname: Pizzatti
authors.forename: Ana Cristina
authors.initials: AC
authors.lastname: Herrera
authors.forename: Stephany
authors.initials: S
authors.lastname: Corrêa
authors.forename: Renata
authors.initials: R
authors.lastname: Binato
authors.forename: Eliana
authors.initials: E
authors.lastname: Abdelhay
mesh_terms: D015153:Blotting, Western; D001943:Breast Neoplasms / Q000145:classification* / Q000235:genetics* / Q000378:metabolism*; D002448:Cell Adhesion / Q000235:genetics / Q000502:physiology; D002853:Chromatography, Liquid; D003598:Cytoskeletal Proteins / Q000378:metabolism; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics / Q000502:physiology*; D057166:High-Throughput Screening Assays / Q000379:methods; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D013058:Mass Spectrometry; D009361:Neoplasm Invasiveness / Q000235:genetics / Q000503:physiopathology; D020543:Proteome / Q000235:genetics / Q000378:metabolism*; D040901:Proteomics / Q000379:methods
chemical_list: D003598:Cytoskeletal Proteins; D020543:Proteome
keywords: breast cancer; high-throughput proteomics; subtypes