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A New Molecular Platform for Authentic Transmitted/Founder Viruses

In the past, nonhuman primate research has relied on only a few infectious molecular clones for numerous diverse research projects including pathogenesis, preclinical vaccine evaluations, transmissions, and host vs. pathogen interactions. But new data suggests that there is a selected phenotype of the simian immunodeficiency virus (SIV) that causes infection.

Study Illuminates K-Ras4B Activation, Which May Help Predict Drug Resistance

Until recently, researchers studying RAS, a family of proteins involved in transmitting signals within cells, believed that the exchange of guanosine 5’-diphosphate (GDP) by guanosine triphosphate (GTP) was sufficient to activate the protein. Once activated, RAS can cause unintended and overactive signaling in cells, which can lead to cell division and, ultimately, cancer.

HIV-1 Viral RNA Dynamics at the Plasma Membrane May Provide Insight into Viral Assembly

Many aspects of how infectious viruses assemble in cells have yet to be completely deciphered. However, as reported in a recent Journal of Virology paper, researchers may be one step closer to understanding how HIV-1, the virus that causes AIDS, assembles and replicates.

Novel Method Developed to Further the Understanding of DNA Palindromes

Editor's note: Platinum Highlight articles are noteworthy publications selected periodically by Dr. Craig Reynolds, associate director, National Cancer Institute, from among the most recently published Platinum Publications.Platinum Highlight Icon

When Alison Rattray and colleagues in the Gene Regulation and Chromosome Biology Laboratory (GRCBL) examined a mutant yeast cell they had isolated in a screen, they noticed something strange.

The DNA exhibited a “very specific, but weird, rearrangement,” she explained. The arrangement turned out to be a DNA palindrome, “opening the door to studying these elusive DNA motifs,” she said.

A Novel Ras Effector Pathway Found to Play Significant Role in Tumor Suppression

By Nancy Parrish, Staff Writer; photo by Richard Frederickson, Staff PhotographerPlatinum Highlight Icon

Normal cells have mechanisms to prevent the development of cancer. Among these is a type of tumor suppressor mechanism known as oncogene-induced senescence, or OIS, which halts the uncontrolled growth of cells caused by mutations in oncogenes. The oncogene Ras plays a crucial role in inducing OIS through a specific cascade of proteins, as reported in a recent article in Molecular and Cellular Biology by Jacqueline Salotti, Ph.D., and colleagues in the Eukaryotic Transcriptional Regulation Section of the Mouse Cancer Genetics Program, Center for Cancer Research (CCR).

Interaction between EphrinB1 and CNK1 Found to Play Role in Tumor Progression

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By Nancy Parrish, Staff Writer

The family of proteins known as ephrins plays a critical role in a variety of biological processes. In a recent article in the Journal of Biological Chemistry, Hee Jun Cho, Ph.D., and colleagues report on the interaction between proteins CNK1 and ephrinB1 that promotes cell movement. Their findings may have an important implication in developing new therapeutics for reducing metastases in certain cancers.

“Eph and ephrin signaling has become an area of intense interest due to the influence these molecules exert on the control of cell adhesion and cell movement,” Cho said. “This signaling affects the formation of tissues during development and has been shown to play an instructive role in angiogenesis, as well as tumor cell invasion.”

Monomeric CH3: A Small, Stable Antibody Domain with Therapeutic Promise

By Ashley DeVine, Staff WriterPlatinum Highlight Icon

Antibody domains are emerging as promising biopharmaceuticals because of their relatively small size compared to full-sized antibodies, which are too large to effectively penetrate tumors and bind to sterically restricted therapeutic targets.

In an article published in The Journal of Biological Chemistry, Tianlei Ying, Ph.D., Dimiter Dimitrov, Ph.D., and their colleagues in the Protein Interactions Group, Cancer and Inflammation Program, Center for Cancer Research, reported their design of a novel antibody domain, monomeric CH3 (mCH3).

Gut Microorganisms Found Necessary for Successful Cancer Therapy

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By Nancy Parrish, Staff Writer

Humans play host to trillions of microorganisms that help our bodies perform basic functions, like digestion, growth, and fighting disease. In fact, bacterial cells outnumber the human cells in our bodies by 10 to 1.1

The tens of trillions of microorganisms thriving in our intestines are known as gut microbiota, and those that are not harmful to us are referred to as commensal microbiota. In a recent paper in Science, NCI scientists described their discovery that, in mice, the presence of commensal microbiota is needed for successful response to cancer therapy.

New Approach for Producing and Purifying IL-15 Heterodimers That Have Potent Immune Effect

Platinum Highlight IconBy Nancy Parrish, Staff Writer

Cytokines are proteins that play a crucial role in the human immune system by delivering messages that trigger the activation of immune cells to fight off attacks from viruses or other invaders.

Cristina Bergamaschi, Ph.D., NCI Center for Cancer Research, has been studying the mechanism of expression and function of a cytokine known as interleukin-15 (IL-15) for the last five years, in collaboration with Elena Chertova, Ph.D., and other researchers in the Retroviral Protein Chemistry Core (RPCC) of the AIDS and Cancer Virus Program (ACVP), Frederick National Laboratory for Cancer Research.