In this week's Science, an international research group presents genome-wide chromatin accessibility profiles of 410 tumor samples across 23 cancer types from The Cancer Genome Atlas (TCGA), identifying 562,709 transposase-accessible DNA elements that "substantially extend the compendium of known cis-regulatory elements." Applying ATAC-seq — a sequencing-based method for studying transposase-accessible chromatin — to TCGA data reveals "a large number of putative distal enhancers that distinguish molecular subtypes of cancers, uncovers specific driving transcription factors via protein-DNA footprints, and nominates long-range gene-regulatory interactions in cancer." The findings demonstrate the potential of a systematic approach to studying the noncoding genome in cancer for disease diagnosis and therapy, the authors say. Genome Web as more on this, here.
And in Science Translational Medicine, a team led by Weill Cornell Medicine researchers reports a systems biology-based approach for repurposing drugs for medulloblastoma, the common form of pediatric brain cancer with subtypes that are difficult to treat due to intragroup heterogeneity. The investigators developed an approach that combines an algorithm with networks of drug responses derived from the genomic profiles of medulloblastoma patients with the difficult-to-treat subtypes, and apply it to more than 1,300 drug candidates. Among the findings are five approved heart failure drugs with potential as treatments for medulloblastoma — including one that prolonged survival in mouse models of the disease. "Our strategy could potentially be used to accelerate the repositioning of treatments for other human cancers that lack clearly defined rational targets," the researchers write.