Well-known cancer gene NRAS produces 5 variants, study finds

A new study shows that a gene discovered 30 years ago and now known to play a fundamental role in cancer development produces five different gene variants (called isoforms), rather than just the one original form, as thought.The study of the NRAS gene by researchers at The Ohio State University Comprehensive Cancer Center — Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC — James) identified four previously unknown variants that the NRAS gene produces.The finding might help improve drugs for cancers in which aberrant activation of NRAS plays a crucial role. It also suggests that NRAS might affect additional target molecules in cells, the researchers say.The isoforms show striking differences in size, abundance and effects. For example, the historically known protein (isoform 1) is 189 amino-acids long, while one of the newly discovered variants, isoform 5, is only 20 amino-acids long.The study is published in the Proceedings of the National Academy of Sciences.”We believe that the existence of these isoforms may be one reason why NRAS inhibitors have so far been unsuccessful,” says corresponding author Albert de la Chapelle, MD, PhD, professor of Medicine and the Leonard J. Immke Jr. and Charlotte L. Immke Chair in Cancer Research.Co-senior author Clara D. Bloomfield, MD, Distinguished University Professor and Ohio State University Cancer Scholar, notes that one of the newly discovered isoforms might play a greater role in the development of some cancers than the known protein itself.”Targeting the NRAS pathway may have been unsuccessful in the past because we were unaware of the existence of additional targets of these novel isoforms,” says Bloomfield, who is also senior adviser to the OSUCCC — James and holds the William Greenville Pace III Endowed Chair in Cancer Research.”The discovery of these isoforms might open a new chapter in the study of NRAS,” says first author Ann-Kathrin Eisfeld, MD, a postdoctoral fellow in the laboratories of de la Chapelle and of Bloomfield. “Knowing that these isoforms exist may lead to the development of drugs that specifically decrease or increase the expression of one of them and provide more effective treatment for cancer patients.”For this study, de la Chapelle, Eisfeld and their colleagues analyzed expression of the NRAS isoforms in a variety of normal and matched tumor samples. …

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Will your grandmother’s diet increase your risk of colon cancer?

Will a multi-generational exposure to a western type diet increase offspring’s chance of developing colon cancer? Will cancer-fighting agents, like green tea, help combat that increased risk?Those are the two questions Abby Benninghoff, an assistant professor in Utah State University’s College of Agriculture and Applied Sciences, will attempt to answer thanks to a $500,000 grant from the U.S. Department of Agriculture.”Simply put, if your grandmother ate a poor diet, will green tea be beneficial for you or not,” Benninghoff said.Benninghoff and her two collaborators, Korry Hintze and Robert Ward, both associate professors of nutrition, dietetics and food sciences, have developed a diet that mimics typical U.S. nutrition for studies of human cancer using animal models. In this case, rodents with cancer will be studied, which will allow Benninghoff to look at the effects of the diet on multiple generations in a short period of time.Benninghoff, predicts that green tea will have a greater benefit to those mice that are exposed to the western diet than those on a healthy diet. She also believes that the more generations exposed to the western diet, the greater the risk of colon cancer in the offspring.”In the end, what we’re hoping is to be able to determine if there are certain populations that would benefit from a diet modification, an increase consumption of green tea,” Benninghoff said. She also hopes the consequences of this diet will be better understood for the benefit of future generations.Story Source:The above story is based on materials provided by Utah State University. Note: Materials may be edited for content and length.

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It’s alive! Bacteria-filled liquid crystals could improve biosensing

Plop living, swimming bacteria into a novel water-based, nontoxic liquid crystal and a new physics takes over. The dynamic interaction of the bacteria with the liquid crystal creates a novel form of soft matter: living liquid crystal.The new type of active material, which holds promise for improving the early detection of diseases, was developed by a research collaboration based at Ohio’s Kent State University and Illinois’ Argonne National Laboratory. The team will present their work at the 58th annual Biophysical Society Meeting, held in San Francisco, Feb.15-19.As a biomechanical hybrid, living liquid crystal moves and reshapes itself in response to external stimuli. It also stores energy just as living organisms do to drive its internal motion. And it possesses highly desirable optical properties. In a living liquid crystal system, with the aid of a simple polarizing microscope, you can see with unusual clarity the wake-like trail stimulated by the rotation of bacterial flagella just 24-nanometers thick, about 1/4000th the thickness of an average human hair.You can also control and guide active movements of the bacteria by manipulating variables such as oxygen availability, temperature or surface alignment, thus introducing a new design concept for creating microfluidic biological sensors. Living liquid crystal provides a medium to amplify tiny reactions that occur at the micro- and nano-scales — where molecules and viruses interact — and to also easily optically detect and analyze these reactions. That suits living liquid crystal to making sensing devices that monitor biological processes such as cancer growth, or infection. Such microfluidic technology is of increasing importance to biomedical sensing as a means of detecting disease in its earliest stages when it is most treatable, and most cost-effectively managed.”As far as we know, these things have never been done systematically as we did before in experimental physics,” explained Shuang Zhou, a Ph.D. candidate at Ohio’s Kent State University. …

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Android antiviral products easily evaded

May 30, 2013 — Think your antivirus product is keeping your Android safe? Think again. Northwestern University researchers, working with partners from North Carolina State University, tested 10 of the most popular antiviral products for Android and found each could be easily circumnavigated by even the most simple obfuscation techniques.

“The results are quite surprising,” said Yan Chen, associate professor of electrical engineering and computer science at Northwestern’s McCormick School of Engineering and Applied Science. “Many of these products are blind to even trivial transformation attacks not involving code-level changes — operations a teenager could perform.”

The researchers began by testing six known viruses on the fully functional versions of 10 of the most popular Android antiviral products, most of which have been downloaded by millions of users.

Using a tool they developed called DroidChameleon, the researchers then applied common techniques — such as simple switches in a virus’s binary code or file name, or running a command on the virus to repackage or reassemble it — to transform the viruses into slightly altered but equally damaging versions. Dozens of transformed viruses were then tested on the antiviral products, often slipping through the software unnoticed.

All of the antiviral products could be evaded, the researchers found, though their susceptibility to the transformed attacks varied.

The products’ shortcomings are due to their use of overly simple content-based signatures, special patterns the products use to screen for viruses, the researchers said. Instead, the researchers suggested, the products should use a more sophisticated static analysis to accurately seek out transformed attacks. Only one of the 10 tested tools currently utilizes a static analysis system.

The researchers chose to study Android products because it is the most commonly used operating system in the United States and worldwide, and because its open platform enabled the researchers to easily conduct analyses. They emphasized, however, that other operating systems are not necessarily more protected from virus attacks.

Antiviral products are improving. Last year, 45 percent of signatures could be evaded with trivial transformations. This year, the number has dropped to 16 percent.

“Still, these products are not as robust and effective as they must be to stop malware writers,” Chen said. “This is a cat-and-mouse game.”

A paper about the research, “Evaluating Android Anti-Malware Against Transformation Attacks,” was presented earlier this month at the 8th ACM Symposium on Information, Computer and Communications Security (ASIACCS 2013).

The research has been featured by numerous tech news outlets, including Dark Reading, Information Week, The H, Security Week, Slashdot, HelpNet Security, ISS Source, EFY Times, Tech News Daily, Fudzilla, and VirusFreePhone, as well as the German IT website Heise Security. It has also attracted the attention of several antivirus software manufacturers interested in the testing system, Chen said.

In addition to Chen, Vaibhav Rastogi, a PhD candidate at Northwestern, and Xuxian Jeng of North Carolina State University authored the work.

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