ScienceDaily (June 19, 2012) Double-stranded breaks in cellular DNA can trigger tumorigenesis. LMU researchers have now determined the structure of a protein involved in the repair and signaling of DNA double-strand breaks. The work throws new light on the origins of neurodegenerative diseases and certain tumor types. Agents such as radiation or environmental toxins can cause double-stranded breaks in genomic DNA, which facilitate the development of tumors or the neurodegenerative disorders ataxia telangiectasia (AT) and AT-like disease (ATLD). Hence efficient repair mechanisms are essential for cell survival and function. The so-called MRN complex is an important component of one such system, and its structure has just been elucidated by a team led by Professor Karl-Peter Hopfner of LMU's Gene Center. Malignant mutations The MRN complex consists of the nuclease Mre11, the ATPase Rad50 and the protein Nbs1. Nbs1 is responsible for recruiting the protein ATM, which plays a central role in early stages of the cellular response to DNA damage, to the site of damage. "How the MRN complex actually recognizes double-stranded breaks is still not clear," says Hopfner. He and his colleagues therefore set out to clarify the issue by analyzing the structures of mutant, functionally defective versions of … Continue reading →

CARLSBAD, Calif., June 19, 2012 /PRNewswire/ -- Life Technologies Corporation (LIFE) today announced it has partnered with The Hospital for Sick Children (SickKids) to advance pediatric genomic research on the Ion Proton Sequencer. Under the agreement, the semiconductor-based platform will be the primary instrument on which multiple clinical research samples will be mapped daily on four sequencers in the hospital's newly launched Centre for Genetic Medicine. SickKids and Life Technologies will collaborate on developing sequencing workflows and protocols for the Ion Proton System that are tailored for studies of interest to researchers in the Centre. The first collaborative project will focus on sequencing clinical research samples to better understand the genetics behind autism, with a long-term goal to sequence up to 10,000 genomes per year to study various diseases in children. "The perfect storm of unparalleled advances in genome sequencing technology and information science, and a captivated hospital striving for new ways to move forward in medical treatment, bring us to this important day," says the new Centre's Co-Director, Dr. Stephen Scherer, who also leads The Centre for Applied Genomics at SickKids and the University of Toronto's McLaughlin Centre. "We are very excited to work with Life Technologies to enhance … Continue reading →

Psychiatrists often try two or more medications in a patient suffering with major depression before settling on the one that seems to work best for that individual. Sometimes, after several are tried and abandoned, two (or even three) are used in combination. Medication selection is part of the art of psychiatry, but, now, testing is available that promises to make it more of a science. A company called AssureRx Health now offers what it calls GeneSightRxpharmacogenomic laboratory testing that helps identify which antidepressants are a good match for a persons genetic makeup, and which are not so good a match. Sometimes, the testing reveals why three or four antidepressants havent worked for a patient, while pointing in the direction of one that might. This is extremely good news, because psychiatrists have several different kinds of antidepressants to choose fromsome which increase the activity of the brain chemical messenger serotonin, some which increase the activity of the brain chemical messenger norepinephrine and some which increase both. And they do so by varying mechanisms, requiring the activity of different enzymes. The technology behind GeneSightRx actually determines which genetic variantsin terms of the enzymes that are activated by antidepressantsa person possesses. Different antidepressants … Continue reading →

Public release date: 19-Jun-2012 [ | E-mail | Share ] Contact: Jeremy Moore jeremy.moore@aacr.org 215-446-7109 American Association for Cancer Research LAKE TAHOE, Nev. Results of some preclinical trials have shown that low doses of the antidiabetic drug metformin may effectively destroy cancer stem cells, a group of cells that are considered to be responsible for tumor initiation and, because they are resistant to standard chemotherapies, tumor relapse. In addition, when metformin was combined with a standard chemotherapy used for pancreatic cancer, the combination treatment was able to efficiently eradicate both cancer stem cells and more differentiated cancer cells, which form the bulk of the tumor, according to data presented by Christopher Heeschen, M.D., Ph.D., at the American Association for Cancer Research's Pancreatic Cancer: Progress and Challenges conference, held in Lake Tahoe, Nev., from June 18-21, 2012. Heeschen is professor for experimental medicine at the Spanish National Cancer Research Centre in Madrid, Spain. Most clinical trials of pancreatic cancer conducted during the last 15 years have failed to show marked improvement in median survival, suggesting that the selected approaches were not sufficient for several reasons, according to Heeschen. In recent years, researchers have identified cancer stem cells which, as opposed to … Continue reading →