Elucidation of the mutational landscape of human cancer has progressed rapidly and been accompanied by the development of therapeutics targeting mutant oncogenes. However, a comprehensive mapping of cancer dependencies has lagged behind and the discovery of therapeutic targets for counteracting tumor suppressor gene loss is needed. To identify vulnerabilities relevant to specific cancer subtypes, we conducted a large-scale RNAi screen in which viability effects of mRNA knockdown were assessed for 7,837 genes using an average of 20 shRNAs per gene in 398 cancer cell lines.
View Article and Find Full Text PDFResistance to cancer therapies presents a significant clinical challenge. Recent studies have revealed intratumoral heterogeneity as a source of therapeutic resistance. However, it is unclear whether resistance is driven predominantly by pre-existing or de novo alterations, in part because of the resolution limits of next-generation sequencing.
View Article and Find Full Text PDFAssessing the functional significance of novel putative oncogenes remains a significant challenge given the limitations of current loss-of-function tools. Here, we describe a method that employs TALEN or CRISPR/Cas9-mediated knock-in of inducible degron tags (Degron-KI) that provides a versatile approach for the functional characterization of novel cancer genes and addresses many of the shortcomings of current tools. The Degron-KI system allows for highly specific, inducible, and allele-targeted inhibition of endogenous protein function, and the ability to titrate protein depletion with this system is able to better mimic pharmacologic inhibition compared with RNAi or genetic knockout approaches.
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