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A large G4C2-repeat expansion in C9orf72 is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Neuronal degeneration associated with this expansion arises from a loss of C9orf72 protein, the accumulation of RNA foci, the expression of dipeptide repeat (DPR) proteins, or all these factors. We report the discovery of a new targeting sequence that is common to all C9orf72 transcripts but enables preferential knockdown of repeat-containing transcripts in multiple cellular models and C9BAC transgenic mice. We optimize stereopure oligonucleotides that act through this site, and we demonstrate that their preferential activity depends on both backbone stereochemistry and asymmetric wing design. In mice, stereopure oligonucleotides produce durable depletion of pathogenic signatures without disrupting protein expression. These oligonucleotides selectively protect motor neurons harboring C9orf72-expansion mutation from glutamate-induced toxicity. We hypothesize that targeting C9orf72 with stereopure oligonucleotides may be a viable therapeutic approach for the treatment of C9orf72-associated neurodegenerative disorders., C9orf72 expansion mutations are the most common genetic cause of ALS and FTD, which have limited therapies. The authors generate stereopure oligonucleotides that selectively deplete expansion-containing transcripts and protect against expansion-associated pathologies in preclinical models.

Colleagues and team members of Arti Hurria, MD will remember that despite her lengthy list of achievements, she was always thinking to the future. Shortly before she passed, Dr. Hurria compiled a "Top 10 Dream List" of items she most wanted to accomplish moving forward. Among the wishes on her list was the development of telehealth-delivered, multidisciplinary, customized care programs for older adults with cancer, especially for those who would otherwise not have access to it. At the time of her passing, Dr. Hurria was in the process of evaluating telehealth interventions within geriatric oncology.

Discovering new medicines is difficult and increasingly expensive. The pharmaceutical industry has responded to this challenge by embracing open innovation to access external ideas. Historically, partnerships were usually bilateral, and the drug discovery process was shrouded in secrecy. This model is rapidly changing. With the advent of the Internet, drug discovery has become more decentralised, bottom-up, and scalable than ever before. The term open innovation is now accepted as just one of many terms that capture different but overlapping levels of openness in the drug discovery process. Many pharmaceutical companies recognise the advantages of revealing some proprietary information in the form of results, chemical tools, or unsolved problems in return for valuable insights and ideas. For example, such selective revealing can take the form of openly shared chemical tools to explore new biological mechanisms or by publicly admitting what is not known in the form of an open call. The essential ingredient for addressing these problems is access to the wider scientific crowd. The business of crowdsourcing, a form of outsourcing in which individuals or organisations solicit contributions from Internet users to obtain ideas or desired services, has grown significantly to fill this need and takes many forms today. Here, we posit that open-innovation approaches are more successful when they establish a reliable framework for converting creative ideas of the scientific crowd into practice with actionable plans.

Recombinant HIV-1 Rev protein was overexpressed in Escherichia coli using translational coupling to the beta-glucuronidase gene and demonstrated to interact with high affinity and specificity with the Rev responsive element (RRE). A complex Rev-dependent binding pattern was observed using the gel shift assay which could be simplified to one or two primary bands in the presence of stoichiometric concentrations of RRE. Competition of these bands with a series of homopolymer RNA species demonstrated that Rev is essentially a poly-G binding protein, although poly-I was also shown to compete for specific RRE binding. The stoichiometry of the Rev-dependent gel shift complexes was determined using 125I-labeled Rev. The stable, lowest mobility complex was determined to possess a ratio of between 7 and 8 Rev molecules per RRE containing RNA fragment while the two fastest migrating complexes contained ratios of one and two Rev molecules per RRE, respectively. Using the Hill equation as a model for cooperative interactions, a Hill coefficient of n(app) = 2 was obtained from fitting of direct nitrocellulose filter binding assays, reflecting cooperatively bound Rev molecules on the RRE under equilibrium binding conditions. An increase in ionic strength from 0.0 to 0.3 M NaCl reduced cooperative Rev binding to the RRE, but specificity of Rev for the RRE relative to antisense RNA was increased 100,000-fold. At molar ratios of Rev to RRE above 2, Rev dissociated from the RRE with a T1/2 of approximately 20-25 min.(ABSTRACT TRUNCATED AT 250 WORDS)

The AP-2 transcription factor family is linked with development of the head and limbs in both vertebrate and invertebrate species. Recent evidence has also implicated this gene family in the evolution of the neural crest in chordates, a critical step that allowed the development and elaboration of the vertebrate craniofacial skeleton. In mice, the inappropriate embryonic expression of one particular AP-2 gene, Tcfap2a, encoding AP-2alpha, results in multiple developmental abnormalities, including craniofacial and limb defects. Thus, Tcfap2a provides a valuable genetic resource to analyze the regulatory hierarchy responsible for the evolution and development of the face and limbs. Previous studies have identified a 2-kilobase intronic region of both the mouse and human AP-2alpha locus that directs expression of a linked LacZ transgene to the facial processes and the distal mesenchyme of the limb bud in transgenic mice. Further analysis identified two highly conserved regions of approximately 200-400 bp within this tissue-specific enhancer. We have now initiated a transgenic and biochemical analysis of the most important of these highly conserved regions. Our analysis indicates that although the sequences regulating face and limb expression have been integrated into a single enhancer, different cis-acting sequences ultimately control these two expression domains. Moreover, these studies demonstrate that a conserved STAT binding site provides a major contribution to the expression of Tcfap2a in the facial prominences.

RNA-based drugs have redefined the universe of tractable targets by putting virtually anything that is gene encoded within reach of a disease-modifying agent, turning RNA into the biotech industry's de facto third drug modality.

A UNC Chapel Hill team has found a way to block multiple pain receptors by antagonizing the lipid kinase PIP5K1C. Although a PIP5K1C inhibitor alleviates chronic pain in multiple mouse models, the lethality of PIP5K1C mutations suggests that titrating the right dose will be key for safety.

Rare pediatric diseases are getting a boost from Alexion Pharmaceuticals, who recently announced a research collaboration with Cincinnati Children's Hospital Medical Center.

As the Structural Genomics Consortium enters its second decade, SciBX spoke with Aled Edwards about how the open-access business model has evolved globally and the organization's plans to engage clinician scientists and add a site in South America.

Although the therapeutic utility of CRISPR-based approaches has yet to be demonstrated, venture dollars are flowing into new companies developing the platform. Proof of concept may come faster than expected as new findings show that a CRISPR-based therapeutic can correct a mutation in adult mice with genetic liver disease.

An international team has found a new pathway in NK cells that leads to the rejection of metastatic tumors. It remains unclear which components of the pathway will make the best targets.

The nanoscale, tiny by any definition, ranges from approximately 1 to 100 nanometers; for reference, a human hair is roughly 80,000 nanometers in width. Nanotechnology or molecular engineering at the nanoscale promises great benefits to molecular medicine. The merger of these fields necessitates the types of interdisciplinary collaborations that foster ingenuity. Nanotechnology offers new options for drug delivery and nanomaterials can enhance the development of medical imaging modalities. Nanoscale sensors offer impressive improvements in sensitivity for disease biomarkers, and nanoscale bioengineering offers a multitude of opportunities to study and treat disease with synthetic biomolecules or via tissue regeneration.The unique physical, chemical and biological properties of nanomaterials also raise questions about safety and therefore offer new challenges to regulatory bodies. In 2006, the US Food and Drug Administration (FDA) initiated the Nanotechnology Task Force to assess the state of the science and to evaluate regulatory issues; the report produced by this group is available for download via the website of the FDA (http://www.fda.gov/ScienceResearch/SpecialTopics/Nanotechnology/NanotechnologyTaskForceReport2007/default.htm). Around the same time, the European Medicines Agency (EMEA) created the Innovation Task Force (ITF; http://www.emea.eu.int/htms/human/itf/itfintro.htm) to ensure coordination and regulatory competence for emerging technologies. Although regulatory agencies continue to monitor developments in nanotechnology and policies surrounding the use of nanomaterials will continue to evolve, both the FDA and EMEA encourage scientists and manufacturers to communicate with them early in the development process for products using these materials.Against this backdrop, Trends in Molecular Medicine is pleased to present a special issue devoted to Nanomedicine. Given the breadth of molecular medicine and the multitude of areas where nanotechnology is impacting this field, the collection of articles in this issue reflects merely a sample of the exciting advances in this arena.Molecular imaging, a powerful tool for the diagnosis and monitoring of diseases including cancer, cardiovascular disease and neurological disorders, is an area where nanotechnology is already impacting medicine. Importantly, nanomaterials increase the sensitivity of molecular imaging modalities creating opportunities for clinicians to detect disease earlier. In this issue, Cho and colleagues review advances in the development of inorganic particle-based contrast agents that promise to improve existing imaging modalities and create new options for multimodal technologies. Although iron oxide nanoparticles are already in clinical use, this review offers an overview of additional particles in preclinical development, and how various surface modifications can impact the behavior of these molecules in circulation and enhance their functionality.He and colleagues review advances in near-infrared (NIR) fluorescent nanoprobes and the advantages they offer over conventional NIR probes and other fluorescent dyes as well as different modes of targeting NIR fluorescence to tumors, including passive targeting, active targeting and the generation of activatable probes. These developments, among others, are moving this technology rapidly towards the clinic; however, the authors conclude by highlighting challenges that must be overcome for this work to translate into improved patient care.In addition to serving as molecular imaging agents, nanoparticles can carry cargo, such as small-molecule drugs for cancer treatment. Chen reviews nanocarriers that can affect features of small-molecule drugs making them more suitable for clinical use, improving their efficacy and reducing their toxicity. Chen also reviews mechanisms for achieving controlled release of agents in tumors; she further highlights targeting tumor metastasis as a major area of ongoing research, identifying important questions that remain.Nanotechnology has also improved the sensitivity of biosensors, including those used by patients with diabetes to monitor their blood glucose levels. Cash and Clark review the ways nanomaterials are improving properties of available sensors and allowing the fabrication of new sensors. The authors also review the emergence of “smart tattoos”, temporary sensors in the skin that change color in response to fluctuations in glucose levels, that could replace the invasive finger-prick devices currently used by patients and provide around-the-clock monitoring, which should empower patients to better manage their disease.Bioengineering with nanomaterials is opening new doors for research, treatment and regeneration. In this issue, Luthi and colleagues review strategies to treat atherosclerosis by affecting levels of circulating cholesterol. A common goal of current preventative therapies in heart disease is to increase the levels of high-density lipoproteins (HDLs), a heterogeneous collection of lipoprotein cholesterol transporters. Emerging evidence indicates that disparate HDL species are not biologically equivalent. The authors suggest that nanotechnology offers the opportunity to synthesize well-defined and disparate HDL species so their biological properties can be systematically studied, potentially paving the way for therapies with synthetic HDLs or improving imaging options for detecting and monitoring atherosclerotic plaques.One common outstanding question identified by authors in this issue is: how do the physical and chemical properties of nanoparticles influence biodistribution and toxicity? Cho and colleagues suggest this question will have to be addressed on a particle-by-particle basis; however, because this appears to be such an important issue, which will affect the use of the various nanoparticles in humans, we hope these reviews will inspire new efforts to address this important question.Finally, Trends in Molecular Medicine would like to thank all of the contributors to this special issue, the authors and the referees, for making this issue possible, and we hope you enjoy the articles as much as we did.

The AP-2 family of transcription factors are defined by the presence of a novel DNA binding domain, termed a 'basic helix-span-helix' motif. The AP-2 genes regulate important aspects of vertebrate embryogenesis and have also been linked to the control of cell proliferation and tumorigenesis, but the cellular targets that the AP-2 proteins control are largely undefined. In particular, since only a limited number of sequences have previously been utilized to define the nature of the AP-2 binding site, the range of DNA sequences recognized by the AP-2 proteins remains unknown. We have therefore utilized a SELEX analysis to identify multiple new AP-2[alpha] binding sites. Moreover, we have devised a novel missing phosphate and nucleotide competition analysis to characterize the residues in the binding site required for AP-2[alpha] protein:DNA contact. These studies suggest that the AP-2[alpha] protein:DNA complex is flexible and indicate that AP-2[alpha] can bind three related sequence motifs: GCC N3 GGC, GCC N4 GGC and GCC N3/4 GGG. The availability of these more refined consensus sequences should assist in the identification of target genes for this critical transcription factor.

Researchers have found that inhibiting either factor XII or factor XI can provide thromboprotection without increasing the risk of bleeding. Both targets could eliminate the main drawback of existing anticoagulants.

Although siRNAs have been validated as therapeutics to knock down gene expression, short double-stranded RNAs can also turn on gene expression. An academic team sponsored by MiNA Therapeutics has attacked liver cancer in rats by using a short activating RNA to upregulate expression of a tumor suppressor.

UCSF- and Harvard Medical School–led teams have independently synthesized the first covalent inhibitors of a common oncogenic form of KRAS. Araxes has licensed the UCSF team's findings and has partnered with Johnson & Johnson to optimize the compounds for in vivo testing.

VEGF-A to repair post–myocardial infarction heart damage has stumbled in the clinic because of delivery issues. Now, a multinational team thinks it has solved the delivery problem by using synthetic RNA. The molecule is partnered with Moderna and AstraZeneca.

An information explosion on the numbers and mechanisms of functional RNAs has spurred oligonucleotide-based therapeutic development. Pharmas and big biotechs are carving up the space via partnerships, adding multiple nucleic acid–based technologies to their drug discovery toolboxes. The newest kids on the block are noncoding RNAs such as microRNAs and long noncoding RNAs, which can selectively turn on expression of a given gene and thus achieve therapeutic outcomes that no other drug platform can.

The Research Center for Molecular Medicine of the Austrian Academy of Sciences and Haplogen have generated a library of haploid knockout human cells that allows for the systematic investigation of gene function in vitro. Haplogen is using the library for its drug discovery programs.

Determining whether a compound binds its intended target is a fundamental question in drug discovery, but assays for measuring target engagement in vivo can be indirect. A Swedish group has remedied the situation with a new assay and founded a biotech, Pelago, to optimize the technology.

A German team has identified a compound that disrupts a protein-protein interaction that localizes K-Ras to the cell membrane, thus selectively inhibiting tumor growth. The interface provides a new small molecule binding site for the handful of companies and academics working on ways to tackle the previously undruggable Ras family.

An international team led by Novartis and the J. Craig Venter Institute has improved the speed and accuracy of seed influenza virus production for large-scale vaccine manufacture. Adoption of the platform could shave weeks off the time needed to generate vaccine in response to a pandemic.

Aragon researchers have uncovered how a specific androgen receptor mutation turns second-generation antagonists for prostate cancer into agonists. The results could allow the company, which is being acquired by Johnson & Johnson, to develop third-generation molecules that overcome the resistance mechanism.