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Purpose: The Wnt/β-catenin (β-cat) signaling cascade is a key regulator of development, and dysregulation of Wnt/β-cat contributes to selected cancers, such as colorectal, breast, and hepatocellular carcinoma, through abnormal activation of Wnt target genes. To identify novel modulators of the Wnt/β-cat pathway that may emerge as therapeutic targets, we did an unbiased high-throughput RNA interference screen.Experimental Design: A synthetic oligonucleotide small interfering RNA library targeting 691 known and predicted human kinases was screened in Wnt3a-stimulated human cells in a live cell luciferase assay for modulation of Wnt/β-cat–dependent transcription. Follow-up studies of a selected high-confidence “hit” were conducted.Results: A robust quartile-based statistical analysis and secondary screen yielded several kinases worthy of further investigation, including Cdc2L1, Lmtk3, Pank2, ErbB3, and, of note, vascular endothelial growth factor receptor (VEGFR)1/Flt1, a receptor tyrosine kinase (TK) with putative weak kinase activity conventionally believed to be a negative regulator of angiogenesis. A series of loss-of-function, genetic null, and VEGFR TK inhibitor assays further revealed that VEGFR1 is a positive regulator of Wnt signaling that functions in a glycogen synthase kinase-3β (GSK3β)–independent manner as a potential synthetic lethal target in Wnt/β-cat–addicted colon carcinoma cells.Conclusions: This unanticipated non-endothelial link between VEGFR1 TK activity and Wnt/β-cat signaling may refine our understanding of aberrant Wnt signaling in colon carcinoma and points to new combinatorial therapeutics targeted to the tumor cell compartment, rather than angiogenesis, in the context of colon cancer. (Clin Cancer Res 2009;15(24):7529–37)

CCR Translation for the Article from Vascular Endothelial Growth Factor Receptor-1 Is Synthetic Lethal to Aberrant β-Catenin Activation in Colon Cancer

Supplementary Data from Vascular Endothelial Growth Factor Receptor-1 Is Synthetic Lethal to Aberrant β-Catenin Activation in Colon Cancer

Purpose: The Wnt/β-catenin (β-cat) signaling cascade is a key regulator of development, and dysregulation of Wnt/β-cat contributes to selected cancers, such as colorectal, breast, and hepatocellular carcinoma, through abnormal activation of Wnt target genes. To identify novel modulators of the Wnt/β-cat pathway that may emerge as therapeutic targets, we did an unbiased high-throughput RNA interference screen. Experimental Design: A synthetic oligonucleotide small interfering RNA library targeting 691 known and predicted human kinases was screened in Wnt3a-stimulated human cells in a live cell luciferase assay for modulation of Wnt/β-cat–dependent transcription. Follow-up studies of a selected high-confidence “hit” were conducted. Results: A robust quartile-based statistical analysis and secondary screen yielded several kinases worthy of further investigation, including Cdc2L1, Lmtk3, Pank2, ErbB3, and, of note, vascular endothelial growth factor receptor (VEGFR)1/Flt1, a receptor tyrosine kinase (TK) with putative weak kinase activity conventionally believed to be a negative regulator of angiogenesis. A series of loss-of-function, genetic null, and VEGFR TK inhibitor assays further revealed that VEGFR1 is a positive regulator of Wnt signaling that functions in a glycogen synthase kinase-3β (GSK3β)–independent manner as a potential synthetic lethal target in Wnt/β-cat–addicted colon carcinoma cells. Conclusions: This unanticipated non-endothelial link between VEGFR1 TK activity and Wnt/β-cat signaling may refine our understanding of aberrant Wnt signaling in colon carcinoma and points to new combinatorial therapeutics targeted to the tumor cell compartment, rather than angiogenesis, in the context of colon cancer. (Clin Cancer Res 2009;15(24):7529–37)

A new type of initiative is empowering graduate students and postdocs to reshape their academic training, providing another avenue to express their passion for research.

Although chronobiology is of growing interest to scientists, physicians, and the general public, access to recent discoveries and historical perspectives is limited. Wikipedia is an online, user-written encyclopedia that could enhance public access to current understanding in chronobiology. However, Wikipedia is lacking important information and is not universally trusted. Here, 46 students in a university course edited Wikipedia to enhance public access to important discoveries in chronobiology. Students worked for an average of 9 h each to evaluate the primary literature and available Wikipedia information, nominated sites for editing, and, after voting, edited the 15 Wikipedia pages they determined to be highest priorities. This assignment ( http://www.nslc.wustl.edu/courses/Bio4030/wikipedia_project.html ) was easy to implement, required relatively short time commitments from the professor and students, and had measurable impacts on Wikipedia and the students. Students created 3 new Wikipedia sites, edited 12 additional sites, and cited 347 peer-reviewed articles. The targeted sites all became top hits in online search engines. Because their writing was and will be read by a worldwide audience, students found the experience rewarding. Students reported significantly increased comfort with reading, critiquing, and summarizing primary literature and benefited from seeing their work edited by other scientists and editors of Wikipedia. We conclude that, in a short project, students can assist in making chronobiology widely accessible and learn from the editorial process.