title: Molecular classification and molecular forecasting of breast cancer: ready for clinical application?
abstract: Profiling breast cancer with expression arrays has become common, and it has been suggested that the results from early studies will lead to understanding of the molecular differences between clinical cases and allow individualization of care. We critically review two main applications of expression profiling; studies unraveling novel breast cancer classifications and those that aim to identify novel markers for prediction of clinical outcome. Breast cancer may now be subclassified into luminal, basal, and HER2 subtypes with distinct differences in prognosis and response to therapy. However, profiling studies to identify predictive markers have suffered from methodologic problems that prevent general application of their results. Future work will need to reanalyze existing microarray data sets to identify more representative sets of candidate genes for use as prognostic signatures and will need to take into account the new knowledge of molecular subtypes of breast cancer when assessing predictive effects.
authors.affiliation: Cancer Genomics Program, Department of Oncology, University of Cambridge, Hutchison/MRC Research Centre, Cambridge, United Kingdom CB22XZ.
authors.forename: James D
authors.initials: JD
authors.lastname: Brenton
authors.forename: Lisa A
authors.initials: LA
authors.lastname: Carey
authors.forename: Ahmed Ashour
authors.initials: AA
authors.lastname: Ahmed
authors.forename: Carlos
authors.initials: C
authors.lastname: Caldas
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics*; D001943:Breast Neoplasms / Q000145:classification / Q000235:genetics*; D005260:Female; D005544:Forecasting; D020869:Gene Expression Profiling; D005819:Genetic Markers; D006801:Humans; D017063:Outcome Assessment, Health Care; D011237:Predictive Value of Tests
chemical_list: D014408:Biomarkers, Tumor; D005819:Genetic Markers