Alzheimer's Disease Wards Off Brain Cancer

Researchers at the Roskamp Institute, in Sarasota, Fla., have shown that mice that naturally develop Alzheimer's disease (AD) are able to ward off the growth of brain cancer. In a series of experiments published in the Journal of Neuroscience, scientists found that cancers in the brains of the Alzheimer mice don't grow as they normally would because their blood supply is choked. It has long been known that in order to grow cancers need large blood supplies, which they hijack from existing normal blood supplies. That is true of the brain cancers tested in the mice. The Roskamp scientists reported that the small protein that causes AD, amyloid, stops cancer blood vessels growing and thus the supply of nutrients and oxygen to the cancer is stifled.

Diabetes and Air Pollution Linked

A national epidemiologic study found a strong, consistent correlation between adult diabetes and particulate air pollution that persists after adjustment for other risk factors like obesity and ethnicity. Researchers from Children's Hospital Boston reported that the relationship was seen even at exposure levels below the current EPA safety limit. Their report, published in Diabetes Care, is among the first large-scale population-based studies to link diabetes prevalence with air pollution. It is consistent with prior lab studies finding an increase in insulin resistance, a precursor to diabetes, in obese mice exposed to particulates, and an increase in markers of inflammation (which may contribute to insulin resistance) in both the mice and obese diabetic patients after particulate exposure.

Explaining Differences in Height

An international team of more than 200 institutions, led by researchers at Children's Hospital Boston, the Broad Institute, and a half-dozen other institutions in Europe and North America, has identified hundreds of genetic variants that together account for about 10 percent of the inherited variation of height among people. Known as the GIANT (Genetic Investigation of ANthropometric Traits) Consortium, the collaboration pooled data from more than 180,000 individuals, including millions of genetic results from each of 46 separate studies in the U.S., Canada, Europe and Australia. In Nature, the researchers reported hundreds of genetic variants associated with height, located in at least 180 different spots in the genome. They further showed that those variants cluster consistently around genes from at least six different biological pathways. Many are located near genes already known to be involved in skeletal growth syndromes, while others implicate previously unrecognized genetic growth regulators, opening up new frontiers for biological studies of height.

HCV Resistance Seen

In recent human trials for a promising new class of drug designed to target the hepatitis C virus (HCV) without shutting down the immune system, some of the HCV strains being treated exhibited signs of drug resistance. In response, an interdisciplinary team of Florida State University biologists, chemists and biomedical researchers devised a genetic screening method that can identify the drug-resistant HCV strains and the molecular-level mechanisms that make them that, helping drug developers to tailor specific therapies to circumvent them. In collaboration with Gilead Sciences and researchers from the University of Heidelberg, in Germany, the research team discovered how the latest drug for HCV works and what changes in the virus that makes it resistant to this unique therapy, according to a paper in PLoS Pathogens.

1,000th Protein Structure Released

The Structural Genomics Consortium (SGC), an international public-private partnership that aims to determine 3-D structures of medically important proteins, has released into the public domain its 1,000th high-resolution protein structure known as JmjD2C, which belongs to a class of proteins involved in epigenetic signaling, a key research area for the SGC. JmjD2C is already known to play a key role in the maintenance of self-renewal in stem cells as well as roles in cancer. Now that its 3-D structure is in the public domain, the group hopes it will spur other scientists to investigate its functions more deeply and understand more clearly its role in epigenetics.

Attacking Rheumatoid Arthritis

A study conducted at Copenhagen University Hospital showed that treatment of rheumatoid arthritis (RA) with disease modifying antirheumatic drugs (DMARDs), glucocorticoids, biologic agents or a combination of agents significantly reduced radiographic evidence of joint destruction, with a relative effect of 48 percent as compared with placebo. A direct comparison between the combination of a biologic agent plus methotrexate and the combination of two DMARDs plus initial glucocorticoids revealed no difference. Study findings were published in Arthritis & Rheumatism.

Spying on a Cell's Nucleus

Duke University bioengineers have not only figured out a way to sneak molecular spies through the walls of individual cells, they can now slip them into the nucleus, where they can report back important information or drop off payloads. Using silver nanoparticles cloaked in a protein from the HIV virus that has an uncanny ability to penetrate human cells, the scientists have demonstrated that they can enter the inner workings of the nucleus and detect subtle light signals from the "spy." The ultimate goal is to be able to spot the earliest possible moment when the genetic material within a cell begins to turn abnormal, leading to a host of disorders, especially cancer. The finding also showed how drugs or other payloads might be delivered directly into the nucleus. The Duke researchers reported their findings in a series of papers, culminating in the latest issue of Nanomedicine.

Immunotherapy Add-on Boosts Survival

Administering a new form of immunotherapy to children with neuroblastoma, a nervous system cancer, increased the percentage of those who were alive and free of disease progression after two years, according to researchers at the University of California, San Diego School of Medicine and fellow institutions. The percentage rose from 46 percent for children receiving a standard therapy to 66 percent for children receiving immunotherapy plus standard therapy, according to the study published in The New England Journal of Medicine. This is the first clinical trial to document that a combination of anticancer monoclonal antibody (mAb) with cytokines is an effective anticancer therapy, according to the researchers. Overall, the findings presented a clear paradigm shift and established immunotherapy as a cornerstone to high-risk neuroblastoma treatment, they reported.

ADHD is a Genetic Disorder

In a study published online first and in an upcoming issue of Lancet, researchers provided the first direct evidence that attention-deficit/hyperactivity disorder (ADHD) is a genetic condition. ADHD is a brain development disorder, concluded the article written by a team of scientists at the MRC Centre in Neuropsychiatric Genetics and Genomics and department of Psychological Medicine and Neurology, at Cardiff University, UK, and colleagues. The research was funded mostly by the Wellcome Trust. The study involved genetic analysis of DNA from 366 children with ADHD and 1,047 without the condition. The researchers found that children with ADHD were more likely to have small DNA segments duplicated or missing than controls. This type of genetic variation is found to be more common in brain disorders. Thus the new study provided the first direct evidence that ADHD is a neurodevelopmental disorder. They also found significant overlap between these segments, known as copy number variations, and those linked to autism and schizophrenia. While those disorders are currently thought to be entirely separate, there is some overlap between ADHD and autism in terms of symptoms and learning difficulties. The new research suggested there may be a shared biological basis to the two conditions.

Growth Hormone's Impact on Muscle

Growth hormone is used to treat children's growth disorders and has been used by some athletes to promote muscle growth and regeneration. That is because it coordinates skeletal muscle development, nutrient uptake and nutrient use. It is not clear, however, which of these effects are direct and which are indirectly mediated via growth hormone induction of the protein IGF-1. Now a team of researchers at Johns Hopkins University School of Medicine has used mice engineered to lack in their skeletal muscle either the molecule to which growth hormone binds or the molecule to which IGF-1 binds to show that growth hormone control of skeletal muscle development is dependent on IGF-1, whereas its control of nutrient uptake is independent of IGF-1. The authors hope that with additional work, those results will guide more informed use of growth hormone or growth hormone analogues for promoting muscle development and reducing muscle loss. A report of the work was published in the Journal of Clinical Investigation.

New Bacterial Foe in CF

Exacerbations in cystic fibrosis (CF) may be linked to chronic infection with a bacterium called Stenotrophomonas maltophilia, which was previously thought to simply colonize the CF lung. The finding that chronic infection with S. maltophilia is independently linked with an increased risk of exacerbations gives clinicians and researchers a new potential measure of the health status of CF patients, as well as a new potential target in fighting their disease. The findings were published online ahead of the print edition of the American Journal of Respiratory and Critical Care Medicine. The study showed that chronic infection with S. maltophilia, which was previously not regarded as prognostically significant, may have a real impact on the progression of CF in patients.