In Nature this week, research led by Novartis' Feng Cong identified a new molecule in the Wnt signaling pathway that could potentially be a target in Wnt-dependent cancers. Using a chemical genetic screen, the scientists found that XAV939, a small molecule that selectively inhibits beta-catenin-mediated transcription, effectively stabilizes axin. Following up with a chemical proteomic approach, they found that XAV939 stabilizes axin by inhibiting the poly-ADP-ribosylating enzymes tankyrase 1 and tankyrase 2. A related News and Views says XAV939 is a "'druggable' member of the pathway [that] could change our fundamental understanding of Wnt signaling and provide an entrance point for finding drugs that target Wnt-dependent cancers."
Two papers in Nature Nanotechnology point to advances in devices that could save lives. In one, scientists led by Shana Kelley at the University of Toronto have created a small hand-held device that can detect low levels of cancer biomarkers. The work uses electrodes and nucleic acid sensors engineered on a nanoscale level to detect even slight traces of cancer, says a story at Scientific American. "Our team was able to measure biomolecules on an electronic chip the size of your fingertip," Kelley says. They hope it will be commercially available in Canada in the next five years.
In the second paper, led by the University of Cincinnati's Peixuan Guo, researchers modified a connector protein that's part of the bacteriophage phi29 DNA-packaging motor so that it could serve as a channel through which double-stranded DNA can pass between cell membranes. The packaging motor normally allows dsDNA to enter and exit the virus, enabled by connector proteins, one of which is between 3.6 and 6 nanometers wide. Here, they show that when modified and inserted into a lipid bilayer, this protein motor allows dsDNA to translocate across the membrane. The engineered channel could have applications in nanosensing, gene delivery, drug loading, and DNA sequencing, says a blog post at Scientific Blogging.
In work appearing in Nature Genetics, lead author Elaine Fuchs, an HHMI scientist at The Rockefeller University in New York, used a loss-of-function study to show that skin stem cells that lost TCF3 and TCF4 lost their ability to self-renew and repair cells as well as form new hair follicles. The Genetics and Health blog says this is exciting news. "There is so much benefit in this research in helping burn victims grow their skin back, replacing new skin for those who had extensive facial surgeries, and having hair grow back in those who suffer from hair loss."