TY - JOUR A1 - Franco, Hector L. A1 - Nagari, Anusha A1 - Malladi, Venkat S. A1 - Li, Wenqian A1 - Xi, Yuanxin A1 - Richardson, Dana A1 - Allton, Kendra L. A1 - Tanaka, Kaori A1 - Li, Jing A1 - Murakami, Shino A1 - Keyomarsi, Khandan A1 - Bedford, Mark T. A1 - Shi, Xiaobing A1 - Li, Wei A1 - Barton, Michelle C. A1 - Dent, Sharon Y.R. A1 - Kraus, W. Lee T1 - Enhancer transcription reveals subtype-specific gene expression programs controlling breast cancer pathogenesis Y1 - 2018/02/01 JF - Genome Research JO - Genome Research SP - 159 EP - 170 DO - 10.1101/gr.226019.117 VL - 28 IS - 2 UR - http://genome.cshlp.org/content/28/2/159.abstract N2 - Noncoding transcription is a defining feature of active enhancers, linking transcription factor (TF) binding to the molecular mechanisms controlling gene expression. To determine the relationship between enhancer activity and biological outcomes in breast cancers, we profiled the transcriptomes (using GRO-seq and RNA-seq) and epigenomes (using ChIP-seq) of 11 different human breast cancer cell lines representing five major molecular subtypes of breast cancer, as well as two immortalized (“normal”) human breast cell lines. In addition, we developed a robust and unbiased computational pipeline that simultaneously identifies putative subtype-specific enhancers and their cognate TFs by integrating the magnitude of enhancer transcription, TF mRNA expression levels, TF motif P-values, and enrichment of H3K4me1 and H3K27ac. When applied across the 13 different cell lines noted above, the Total Functional Score of Enhancer Elements (TFSEE) identified key breast cancer subtype-specific TFs that act at transcribed enhancers to dictate gene expression patterns determining growth outcomes, including Forkhead TFs, FOSL1, and PLAG1. FOSL1, a Fos family TF, (1) is highly enriched at the enhancers of triple negative breast cancer (TNBC) cells, (2) acts as a key regulator of the proliferation and viability of TNBC cells, but not Luminal A cells, and (3) is associated with a poor prognosis in TNBC breast cancer patients. Taken together, our results validate our enhancer identification pipeline and reveal that enhancers transcribed in breast cancer cells direct critical gene regulatory networks that promote pathogenesis. ER -