title: Co-amplification of CCND1 and EMSY is associated with an adverse outcome in ER-positive tamoxifen-treated breast cancers.
abstract: Amplification of chromosome 11q13 is commonly seen in breast carcinomas and candidate genes from this region include CCND1 and EMSY. Here, we investigate the prognostic significance of CCND1 and EMSY amplification in a large series of breast carcinomas and in BRCA1 and BRCA2 mutation positive breast cancers. Amplification of CCND1 and EMSY was assessed by fluorescent in situ hybridization. Both CCND1 and EMSY amplifications were associated with a significantly worse outcome in ER-positive patients treated with tamoxifen only, in contrast to nonamplified tumors (P = 8.55 x 10(-4) and P = 8.35 x 10(-5), respectively). In multivariable Cox models, which included standard prognostic markers, co-amplification of CCND1 and EMSY was significantly more predictive of outcome than was amplification of either gene alone or neither gene amplified in ER-positive tamoxifen-treated patients (P = 5.47 x 10(-5)). EMSY gene amplification was a significantly less common event in BRCA2 mutation carriers as compared to BRCA1 mutation carriers (9 versus 24%, respectively). In contrast, CCND1 amplification occurred at a similar frequency in both BRCA1 and BRCA2 breast cancers (22 versus 18%, respectively). In summary, co-amplification of CCND1 and EMSY identified a poor prognostic subset of ER-positive tamoxifen-treated patients. In addition, EMSY amplification occurred at a lower frequency in BRCA2 mutation carriers providing evidence to support EMSY amplification as a somatic surrogate for BRCA2 loss in sporadic breast cancer.
authors.affiliation: Center for Translational and Applied Genomics, British Columbia Cancer Agency, 600 W 10th Ave, Vancouver, BC V5Z 4E6, Canada. lbrown5@cw.bc.ca
authors.forename: Lindsay A
authors.initials: LA
authors.lastname: Brown
authors.forename: Karynn
authors.initials: K
authors.lastname: Johnson
authors.forename: Samuel
authors.initials: S
authors.lastname: Leung
authors.forename: Tarek A
authors.initials: TA
authors.lastname: Bismar
authors.forename: Javier
authors.initials: J
authors.lastname: Benítez
authors.forename: William D
authors.initials: WD
authors.lastname: Foulkes
authors.forename: David G
authors.initials: DG
authors.lastname: Huntsman
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics*; D019938:Cyclin D1 / Q000235:genetics*; D005260:Female; D005784:Gene Amplification; D019398:Genes, BRCA1; D024522:Genes, BRCA2; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008875:Middle Aged; D009154:Mutation; D009363:Neoplasm Proteins / Q000235:genetics*; D009687:Nuclear Proteins / Q000235:genetics*; D011379:Prognosis; D016016:Proportional Hazards Models; D011960:Receptors, Estrogen / Q000096:biosynthesis / Q000235:genetics*; D012097:Repressor Proteins / Q000235:genetics*; D020845:Selective Estrogen Receptor Modulators / Q000627:therapeutic use; D016019:Survival Analysis; D013629:Tamoxifen / Q000627:therapeutic use; D046888:Tissue Array Analysis; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; C480344:EMSY protein, human; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D011960:Receptors, Estrogen; D012097:Repressor Proteins; D020845:Selective Estrogen Receptor Modulators; D013629:Tamoxifen; D019938:Cyclin D1