title: Practical implications of gene-expression-based assays for breast oncologists.
abstract: Gene-expression profiling has had a considerable impact on our understanding of breast cancer biology, and more recently on clinical care. Two statistical approaches underlie these advancements. Supervised analyses have led to the development of gene-expression signatures designed to predict survival and/or treatment response, which has resulted in the development of new clinical assays. Unsupervised analyses have identified numerous biological signatures including signatures of cell type of origin, signaling pathways, and of cellular proliferation. Included within these biological signatures are the molecular subtypes known as the 'intrinsic' subtypes of breast cancer. This classification has expanded our appreciation of the heterogeneity of breast cancer and has provided a way to sub-classify the disease in a manner that might have clinical utility. In this Review, we discuss the clinical utility of gene-expression-based assays and their technical potential as clinical tools vis-a-vis the performance of breast cancer biomarkers that are the current standard of care.
authors.affiliation: Department of Genetics and Pathology, Lineberger Comprehensive Cancer Center, University of North Carolina, 450 West Drive, Chapel Hill, NC 27599, USA.
authors.forename: Aleix
authors.initials: A
authors.lastname: Prat
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Ellis
authors.forename: Charles M
authors.initials: CM
authors.lastname: Perou
mesh_terms: D014408:Biomarkers, Tumor; D001943:Breast Neoplasms / Q000235:genetics* / Q000401:mortality; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods*; D018734:Genes, erbB-2 / Q000235:genetics; D006305:Health Status Indicators; D006801:Humans; D008495:Medical Oncology / Q000379:methods* / Q000706:statistics & numerical data; D046228:Microarray Analysis; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D014481:United States
chemical_list: D014408:Biomarkers, Tumor; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone