title: Breast cancer proteomics reveals a positive correlation between glyoxalase             1 expression and high tumor grade.
abstract: Breast cancer is the neoplasia with the highest incidence in women worldwide.             Proteomics approaches have accelerated the discovery of diagnostic and prognostic             biomarkers. Here, we compared the proteomic profiles of breast tumors versus non-tumoral             tissues in order to identify modulated proteins, which could represent potential             markers associated to clinical features. By two-dimensional electrophoresis, we             detected 28 differentially expressed proteins. Among these, 21 proteins were up-regulated             and 7 were down-regulated in tumors (p<0.05). Proteins were identified using             LC/ESI-MS/MS tandem mass spectrometry. One protein was identified as glyoxalase             1 (GLO1), an enzyme involved in detoxification of methylglyoxal, a cytotoxic product             of glycolysis. GLO1 overexpression was confirmed by western blot assays in paired             normal and tumor breast tissues in clinical stages I-III, and by immunohistochemistry             on tissue microarrays (TMA) comprising a cohort of 98 breast tumors and 20 healthy             specimens. Results from TMA demonstrated that GLO1 is overexpressed in 79% of             tumors. Interestingly, GLO1 up-regulation correlates with advanced tumor grade             (p<0.05). These findings demonstrate the association of GLO1 overexpression             with tumor grade and pointed out for additional studies to establish the importance             of GLO1 in breast cancer.
authors.affiliation: Genomics Sciences Program, Oncogenomics and Cancer Proteomics Laboratory, Autonomous University of Mexico city, Mexico City, Mexico.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Fonseca-Sánchez
authors.forename: Sergio
authors.initials: S
authors.lastname: Rodríguez Cuevas
authors.forename: Guillermo
authors.initials: G
authors.lastname: Mendoza-Hernández
authors.forename: Veronica
authors.initials: V
authors.lastname: Bautista-Piña
authors.forename: Elena
authors.initials: E
authors.lastname: Arechaga Ocampo
authors.forename: Alfredo
authors.initials: A
authors.lastname: Hidalgo Miranda
authors.forename: Valeria
authors.initials: V
authors.lastname: Quintanar Jurado
authors.forename: Laurence A
authors.initials: LA
authors.lastname: Marchat
authors.forename: Elizbeth
authors.initials: E
authors.lastname: Alvarez-Sánchez
authors.forename: Carlos
authors.initials: C
authors.lastname: Pérez Plasencia
authors.forename: César
authors.initials: C
authors.lastname: López-Camarillo
mesh_terms: D000369:Aged, 80 and over; D000595:Amino Acid Sequence; D001943:Breast Neoplasms / Q000201:enzymology* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000201:enzymology* / Q000473:pathology; D016022:Case-Control Studies; D045744:Cell Line, Tumor; D015180:Electrophoresis, Gel, Two-Dimensional; D005260:Female; D015870:Gene Expression; D006801:Humans; D007791:Lactoylglutathione Lyase / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D008969:Molecular Sequence Data; D060787:Neoplasm Grading; D010446:Peptide Fragments / Q000737:chemistry; D020543:Proteome / Q000378:metabolism*; D040901:Proteomics; D046888:Tissue Array Analysis
chemical_list: D010446:Peptide Fragments; D020543:Proteome; D007791:Lactoylglutathione Lyase