Overview of Gene Expression Profiling and Novel Translational Technologies in Breast Cancer.

Abstract

Abstract Gene expression profiling has had an enormous impact on many aspects of breast cancer, including elucidation of the basic mechanisms of carcinogenesis and mammary development, prediction of outcome and response to treatment, and identification of new subtypes of disease. Importantly, gene expression profiling in breast cancer has allowed the development of biomarkers that are being used in the clinic and/or will become part of routine clinical care in the near future. Genomic profiling is accomplished nowadays by using genome-wide DNA microarray assays, which evaluate thousands of genes with relatively low sensitivity, or qRT-PCR assays, which evaluate small numbers of genes with high sensitivity. The majority of these assays focus on mRNA molecules; however, in recent years, DNA microarrays evaluating other functionally important classes of RNA molecules, such as microRNAs and non-coding RNAs, have been developed and will likely have an impact on our understanding of breast cancer biology. Nonetheless, DNA microarrays and qRT-PCR assays based on mRNA have provided robust platforms for the investigation of breast cancer transcriptomes, and each has resulted in the development of clinically useful prognostic tests (i.e. OncotypeDX and Mammaprint). However, as with all technologies, new methods and platforms are constantly being developed, offering higher speed, lower cost and increased accuracy. Importantly, many of these promising new technologies are compatible with RNA derived from archival formalin-fixed paraffin embedded materials. Therefore, it is likely that gene expression-based assays will continue to play a critical role in the development of novel biomarkers, and the discovery of new targets. In this session, we will cover the basics of DNA microarrays and microarray statistics, and discuss the next generation of technologies to further study the gene expression patterns of breast cancers. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr ES3-1.