The Public Repository of Xenografts enables discovery and randomized phase II-like trials in mice

More than 90% of drugs with preclinical activity fail in human trials, largely due to insufficient efficacy. We hypothesized that adequately powered trials of patient-derived xenografts (PDX) in mice could efficiently define therapeutic activity across heterogeneous tumors. To address this hypothesis, we established a large, publicly available repository of well-characterized leukemia and lymphoma PDXs that undergo orthotopic engraftment, called the Public Repository of Xenografts (PRoXe). PRoXe includes all de-identified information relevant to the primary specimens and the PDXs derived from them. Using this repository, we demonstrate that large studies of acute leukemia PDXs that mimic human randomized clinical trials can characterize drug efficacy and generate transcriptional, functional, and proteomic biomarkers in both treatment-naive and relapsed/refractory disease

Structure Based Drug Design: Inhibition of E6 protein in immortalized HPV cell lines implicated in human epithelial cancers

Background:Human papillomavirus (HPV) has been implicated in nearly 100% of invasive cervical cancers worldwide. HPV DNA has been identified in 30-70% of sexually active women between the ages of 16 and 25 in the USA. Genital warts affect all races, genders and socioeconomic groups. According to the CDC, there are approximately 6.2 million new cases of genital warts annually. They report that there are approximately 20 million people currently infected with HPV in the USA. Concurrent immunosuppression, particularly with organ transplant or HIV, is associated with an increased occurrence of HPV and HPV-induced malignancy. HPV is a small double stranded DNA virus capable of infecting mucosal and cutaneous epithelial tissues. HPV types 16, 18, 31, 33, and 45 are considered “high-risk” as they are most frequently associated with malignant progression. DNA from the high-risk group has been isolated from over 95% of cervical cancers. Furthermore, HPV 16 DNA is found in approximately 50% of cervical cancers and is the most frequent isolate from head and neck cancers, 25-50% of which are attributable to HPV. The HPV E6 protein promotes viral replication and prevents against apoptosis by forming a ubiquitin ligase in complex with E6 associated protein (E6AP). Together, the ligase binds p53 and targets it for degradation. Normally, p53 up-regulates the expression of pro-apoptotic proteins in response to cellular stress. It is the most commonly disrupted tumor suppressor gene. The E6 protein in each of the high-risk viruses share amino acid sequences and are able to bind p53 and target it for degradation. Therefore, inhibition of E6 function is an ideal target for restoring the tumor suppressor function of p53 and allowing for apoptosis of infected cells. There is currently no specific antiviral treatment for HPV, despite its prevalence. Treatment of genital warts and cervical dysplasia involve destruction and removal of the affected tissue. While much effort has been made to develop vaccines against the E6 and E7 proteins of HPV, these options are likely several years from the market. Furthermore, they are a preventative measure and cannot treat the millions of people already infected. We aim to optimize a structure-based inhibitor of the HPV E6 protein. Given that warts tend to develop slowly and that it generally takes years for dysplasia to progress to malignancy, there is a window of opportunity for the treatment of these HPV-associated illnesses. Objectives: This project sought to identify a reproducible and accurate method of measuring the cytotoxic effects of pharmacophores created to inhibit the E6 protein of HPV infected cells. We hope to isolate specific structure-based in vivo inhibitors of HPV E6 and E7 proteins from a collection of previously derived and isolated pharmacophores, identified via in vitrohigh throughput assays. We further hypothesize that killing cells infected with HPV using these specific inhibitors occurs via a p53 dependent pathway. Therefore “priming” cells with agents known to induce p53 will allow for decreased dosing of the lead compounds such that IC50 values will fall into an acceptable “pre-clinical” range of low μM or nM concentrations. Methods:Using HPV16 immortalized SiHa cells containing E6 and E7, HPV18 immortalized HeLa cells, containing E6 and E7, and C33a cells as controls for toxicity, we tested the effect of a series of lead compounds on cell viability. SiHa, HeLa and c33a cell lines were grown in 96 well plates in the presence of varying concentrations of Doxorubicin (1.56nM-100nM), Mitomycin C (31.25nM- 2µM) or water. MTT cell viability assays were carried out at 24, 48 and 72 hours to determine the concentration and time point at which approximately 80% of cells continued to proliferate. Medium without phenol red was ultimately used for the MTT assay as several of the drugs tested have their own intrinsic color, which was found to affect absorbance values during analysis. The cell lines were then grown in the presence of both Mitomycin C (125nM) and varying concentrations of lead compounds. Those pharmacopores which showed killing of SiHa or HeLa cells at lower concentrations or earlier time points than c33a cells were repeated at a broader range of concentrations; MTT assay and data point collection was done at 48h, 72h, and 7 days. The medium and drug solution was changed every 48 hours to ensure adequate cellular nutrition. Results to Date:Approximately 80% of all three cell lines were viable in Mitomycin C at 125nM concentrations until 72hours, when all cell lines showed a drop to approximately 50% viability. Doxorubicin showed less consistent killing at low concentrations, so Mitomycin C was used for presumed synergistic up-regulation of p53. Preliminary assays using both Mitomycin C and pharmacophores (G1-1 through G1-14) showed now improvement in cytotoxicity in the presence of Mitomycin C. The MTT assays were then carried out on cells grown in the presence of pharmocophores verses medium. Lead compounds G1-4, G1-9, G1-13, C-8 and F-10 exhibited greater killing of both HeLa and SiHa cells at 7days, with concentrations between 1 and 10µM. Discussion: This aspect of the study is in its preliminary state. Several factors have affected the in vivo analysis of the isolated lead compounds. In vivoeffectiveness can be assessed by various methods, many of which would provide more specific and objectively analyzed data. However, alternative methods also require that far fewer compounds be assessed at a time. Looking at western blots for p53 protein in the presence of the pharmacophores would provide more information about the cellular pathway in question. Additionally, it would allow us to reassess if Mitomycin C is indeed acting in the way that we presume it to be acting. Coupling the evidence from MTT assay with objective increases in p53 levels would support our hypothesis that the pharmacophores are inducing cellular killing by disrupting the E6 protein. The preliminary data allowed us to determine that the pharmacophores tend to have greater efficacy when the assays are carried out to 7days. It is most accurate and reproducible when performed using phenol red –free medium. Further, the assay is dependant on having very similar cell numbers per well on the 96 well plate. SiHa cells tend to divide more slowly than HeLa cells. Thus, finding the ideal time point and plating cells such that the cell numbers are similar and not overly confluent at that time point is a critical step in preparation. The next step will likely be the use of this information for repeated analysis of the most promising compounds, in conjunction with western blots for p53

Aprepitant for refractory cutaneous T-cell lymphoma-associated pruritus: 4 cases and a review of the literature

Background: Aprepitant is an FDA-approved medication for chemotherapy-induced nausea and vomiting. It blocks substance P binding to neurokinin-1; substance P has been implicated in itch pathways both as a local and global mediator. Case presentations We report a series of four patients, diagnosed with cutaneous T-cell lymphoma, who experienced full body pruritus recalcitrant to standard therapies. All patients experienced rapid symptom improvement (within days) following aprepitant treatment. Conclusion: Aprepitant has been shown in small studies to be efficacious for treating chronic and malignancy-associated pruritus. Prior studies have shown no change in clinical efficacy of chemotherapeutics with concurrent aprepitant administration. These cases further demonstrate that aprepitant can be considered as a therapeutic option in malignancy-associated pruritus and further support the need for larger clinical trials

Assessment of known impacts of unmanned aerial systems (UAS) on marine mammals: data gaps and recommendations for researchers in the United States

The development of advanced technologies to enhance conservation science often outpaces the abilities of wildlife managers to assess and ensure such new tools are safely used in proximity to wild animals. Recently, unmanned aerial systems (UAS) have become more accessible to civilian operators and are quickly being integrated into existing research paradigms to replace manned aircraft. Several Federal statutes require scientists to obtain research permits to closely approach protected species of wildlife such as marine mammals, but the lack of available information on the effects of UAS operations on these species has made it difficult to evaluate and mitigate potential impacts. Here, we present a synthesis of the current state of scientific understanding of the impacts of UAS usage near marine mammals. We also identify key data gaps that are currently limiting the ability of marine resource managers to develop appropriate guidelines, policies or regulations for safe and responsible operation of UAS near marine mammals. We recommend researchers prioritize collecting, analyzing, and disseminating data on marine mammal responses to UAS when using the devices to better inform the scientific community, regulators and hobbyists about potential effects and assist with the development of appropriate mitigation measures.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author