title: Subdivision of molecularly-classified groups by new gene signatures             in breast cancer patients.
abstract: Gene expression patterns as well as gene interactions are under investigation             for their involvement in tumour heterogeneity. The molecular classification of             breast cancer based on hormone receptor expression, grade and HER2 receptor levels,             is indicative but not adequate enough to complete the prognostic data. The objectives             of this study were to validate the prognostic value of 19 genes, solely, and as             parts of classifiers (sets of genes), in breast cancer patients and to determine             whether the expression of these genes and classifiers is correlated with breast             cancer molecular classification. Gene expression was examined in the blood of             88 breast cancer patients and 50 healthy controls using multiplex quantitative             real-time PCR. Patients with a second primary malignancy showed a statistically             significant difference when compared with: i) patients with a single breast cancer,             for an 8-gene classifier (p<0.02); and ii) healthy individuals (classifier             FBX033, FLJ339115) (p<0.01), with respect to gene expression. The classifier             ENY2, USP38 was associated with the development of primary breast cancer. A newly             established classifier (ENY2, USP38, RPS7, Osbpl-1 and ETF1) indicated a statistically             significant association with HER2 subtype patients, compared to patients with             a different molecular classification (p<0.04). The gene FLJ33915 was differentially             expressed in a subgroup of HER2-positive patients with infiltrated axillary lymph             nodes (p<0.028). We validated the prognostic value of 4 classifiers for primary             and second primary malignancy. Evidence of a classifier predicting the HER2 subtype             and the gene FLJ33915 which subdivides HER2 subtype patients is also presented.
authors.affiliation: Laboratory of Experimental Physiology, Medical School, National and Kapodestrian University of Athens, Athens 11527, Greece. aarmakol@med.uoa.gr
authors.forename: Athanasios
authors.initials: A
authors.lastname: Armakolas
authors.forename: George P
authors.initials: GP
authors.lastname: Stathopoulos
authors.forename: Adrianos
authors.initials: A
authors.lastname: Nezos
authors.forename: Apostolos
authors.initials: A
authors.lastname: Theos
authors.forename: Martha
authors.initials: M
authors.lastname: Stathaki
authors.forename: Michael
authors.initials: M
authors.lastname: Koutsilieris
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics*; D001943:Breast Neoplasms / Q000097:blood* / Q000235:genetics*; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008875:Middle Aged; D011379:Prognosis; D059467:Transcriptome
chemical_list: D014408:Biomarkers, Tumor