Tick abundance and infection with three zoonotic bacteria are heterogeneous in a Belgian peri-urban forest.

Ixodes ricinus is a vector of several pathogens of public health interest. While forests are the primary habitat for I. ricinus, its abundance and infection prevalence are expected to vary within forest stands. This study assesses the spatio-temporal variations in tick abundance and infection prevalence with three pathogens in and around a peri-urban forest where human exposure is high. Ticks were sampled multiple times in 2016 and 2018 in multiple locations with a diversity of undergrowth, using the consecutive drags method. Three zoonotic pathogens were screened for, Borrelia burgdorferi s.l., Coxiella burnetii, and Francisella tularensis. The influence of season, type of site and micro-environmental factors on tick abundance were assessed with negative binomial generalized linear mixed-effects models. We collected 1642 nymphs and 181 adult ticks. Ticks were most abundant in the spring, in warmer temperatures, and where undergrowth was higher. Sites with vegetation unaffected by human presence had higher abundance of ticks. Forest undergrowth type and height were significant predictors of the level of tick abundance in a forest. The consecutive drags method is expected to provide more precise estimates of tick abundance, presumably through more varied contacts with foliage. Borrelia burgdorferi s.l. prevalence was estimated from pooled ticks at 5.33%, C. burnetii was detected in six pools and F. tularensis was not detected. Borrelia afzelii was the dominant B. burgdorferi genospecies. Tick abundance and B. burgdorferi s.l. infection prevalence were lower than other estimates in Belgian forests.

Changing incentives to ACCELERATE drug development for paediatric cancer.

BACKGROUND: More effective incentives are needed to motivate paediatric oncology drug development, uncoupling it from dependency on adult drug development. Although the current European and North-American legislations aim to promote drug development for paediatrics and rare diseases, children and adolescents with cancer have not benefited as expected from these initiatives and cancer remains the first cause of death by disease in children older than one. Drug development for childhood cancer remains dependent on adult cancer indications and their potential market. The balance between the investment needed to execute a Paediatric Investigation Plan (PIP) in Europe and an initial Paediatric Study Plan (iPSP) in the US, coupled with the potential financial reward has not been sufficiently attractive to incite the pharmaceutical industry to develop drugs for rare indications such as childhood cancer. METHODS: We propose changes in the timing and nature of the rewards within the European Paediatric Medicine Regulation (PMR) and Regulation on Orphan Medicinal Products (both currently under review), which would drive earlier initiation of paediatric oncology studies and provide incentives for drug development specifically for childhood indications. RESULTS: We suggest modifying the PMR to ensure mechanism-of-action driven mandatory PIP and reorganization of incentives to a stepwise and incremental approach. Interim and final deliverables should be defined within a PIP or iPSP, each attracting a reward on completion. A crucial change would be the introduction of the interim deliverable requiring production of paediatric data that inform the go/no-go decisions on whether to take a drug forward to paediatric efficacy trials. CONCLUSION: Additionally, to address the critical gap in the current framework where there is a complete lack of incentives to promote paediatric-specific cancer drug development, we propose the introduction of early rewards in the Orphan Regulation, with a variant on the US-Creating Hope Act and its priority review vouchers.

Individualized, heterologous chimpanzee adenovirus and self-amplifying mRNA neoantigen vaccine for advanced metastatic solid tumors: phase 1 trial interim results.

Checkpoint inhibitor (CPI) therapies provide limited benefit to patients with tumors of low immune reactivity. T cell-inducing vaccines hold promise to exert long-lasting disease control in combination with CPI therapy. Safety, tolerability and recommended phase 2 dose (RP2D) of an individualized, heterologous chimpanzee adenovirus (ChAd68) and self-amplifying mRNA (samRNA)-based neoantigen vaccine in combination with nivolumab and ipilimumab were assessed as primary endpoints in an ongoing phase 1/2 study in patients with advanced metastatic solid tumors (NCT03639714). The individualized vaccine regimen was safe and well tolerated, with no dose-limiting toxicities. Treatment-related adverse events (TRAEs) >10% included pyrexia, fatigue, musculoskeletal and injection site pain and diarrhea. Serious TRAEs included one count each of pyrexia, duodenitis, increased transaminases and hyperthyroidism. The RP2D was 1012 viral particles (VP) ChAd68 and 30 µg samRNA. Secondary endpoints included immunogenicity, feasibility of manufacturing and overall survival (OS). Vaccine manufacturing was feasible, with vaccination inducing long-lasting neoantigen-specific CD8 T cell responses. Several patients with microsatellite-stable colorectal cancer (MSS-CRC) had improved OS. Exploratory biomarker analyses showed decreased circulating tumor DNA (ctDNA) in patients with prolonged OS. Although small study size limits statistical and translational analyses, the increased OS observed in MSS-CRC warrants further exploration in larger randomized studies.

ACCELERATE - Five years accelerating cancer drug development for children and adolescents.

Rapid evaluation and subsequent regulatory approval of new drugs are critical to improving survival and reducing long-term side-effects for children and adolescents with cancer. The international multi-stakeholder organisation ACCELERATE was created to advance the timely investigation of new anti-cancer drugs. ACCELERATE has enhanced communication and understanding between academia, industry, patient advocates and regulators. It has promoted a mechanism-of-action driven drug development approach and developed Paediatric Strategy Forums. These initiatives have facilitated prioritisation of medicinal products and a focused and sequential strategy for drug development where there are multiple potential agents. ACCELERATE has championed the early assessment of promising drugs in adolescents through their inclusion in adult early phase trials. ACCELERATE has strongly supported alignment between the European Medicines Agency and the US Food and Drug Administration and identification of unmet medical needs through multi-stakeholder collaboration. Early engagement between all stakeholders in the development of new drugs is critical. Innovative clinical trial designs are required, necessitating early discussion with sponsors and regulators. Amplifying the patient advocate voice through inclusion across the drug development continuum will lead to better, patient-centric trials. By these means, children and adolescents with cancer can maximally and rapidly benefit from innovative products to improve outcomes and reduce burdensome sequelae.

The Isolation of Culturable Bacteria in Ixodes ricinus Ticks of a Belgian Peri-Urban Forest Uncovers Opportunistic Bacteria Potentially Important for Public Health.

Most bacteria found in ticks are not pathogenic to humans but coexist as endosymbionts and may have effects on tick fitness and pathogen transmission. In this study, we cultured and isolated 78 bacteria from 954 Ixodes ricinus ticks collected in 7 sites of a Belgian peri-urban forest. Most isolated species were non-pathogenic environmental microorganisms, and were from the Firmicutes (69.23%), Actinobacteria (17.95%) and Proteobacteria (3.84%) phyla. One bacterium isolate was particularly noteworthy, Cedecea davisae, a rare opportunistic bacterium, naturally resistant to various antibiotics. It has never been isolated from ticks before and this isolated strain was resistant to ampicillin, cefoxitin and colistin. Although cultivable bacteria do not represent the complete tick microbiota, the sites presented variable bacterial compositions and diversities. This study is a first attempt to describe the culturable microbiota of ticks collected in Belgium. Further collections and analyses of ticks of different species, from various areas and using other bacterial identification methods would strengthen these results. However, they highlight the importance of ticks as potential sentinel for opportunistic bacteria of public health importance.

Environmental determinants of Anaplasma phagocytophilum infection in cattle using a kernel density function.

The study of vector-borne zoonotic diseases often relies on partial data, because of the constraints associated with observing various elements of the transmission cycle: the pathogen, the vector, the host - wild or domestic. Each angle comes with its own practical challenges, leading to data reflecting poorly either on spatial or temporal dynamics, or both. In this study, we investigated the effect of landscape on the presence of bovine ehrlichiosis infection in Walloon cattle. This disease is transmitted to cattle through the bite of a tick infected by the bacterium Anaplasma phagocytophilum. The first case of bovine ehrlichiosis in the southern region of Belgium (Wallonia) was detected in 2005 and the high seroprevalence found in herds suggests that the disease is endemic. The presence of antibodies of A. phagocytophilum in one cow selected in each of 1445 herds in 2010 and 2011 was detected using indirect immunofluorescence. Samples were geolocated at the farm. However, the precise location of infection remains uncertain. To account for the data sparsity, we elaborated a spatial index for the intensity of the presence of seropositive animals, based on a non-parametric kernel density estimation. We examined this index with the landscape surrounding the pastures, using multiple regressions. Landscape factors were selected using a conceptual framework based on the ecological resources needed for the transmission cycle of A. phagocytophilum. Results suggest that our spatial index adequately reflected infection presence in cattle in Wallonia, which was highest in central regions, corresponding to more forested and fragmented landscapes. We noticed that the presence of large hosts, wild or domestic, as well as the composition and configuration of the landscape of the pasture, influenced the capacity of the pasture to support the presence of bovine ehrlichiosis in Walloon herds. This is consistent with the ecology of A. phagocytophilum and current knowledge about risk factors of tick-borne diseases in cattle at the regional scale. The nature of the kernel density index, based on uncertainties over the location of cases positive to A. phagocytophilum, reflected the infectiousness profile at the landscape and not at the pasture level. Results also highlighted that the effects of some environmental variables remain, even when considering the different agro-geographic regions of Wallonia, which present contrasted landscapes and different levels of intensity of A. phagocytophilum infection. The kernel density index is a useful tool to help veterinary practitioner to quickly target areas where A. phagocytophilum infection is likely.

Radiological Evaluation of Newly Diagnosed Non-Brainstem Pediatric High-Grade Glioma in the HERBY Phase II Trial.

PURPOSE: The HERBY trial evaluated the benefit of the addition of the antiangiogenic agent Bevacizumab (BEV) to radiotherapy/temozolomide (RT/TMZ) in pediatric patients with newly diagnosed non-brainstem high-grade glioma (HGG). The work presented here aims to correlate imaging characteristics and outcome measures with pathologic and molecular data. EXPERIMENTAL DESIGN: Radiological, pathologic, and molecular data were correlated with trial clinical information to retrospectively re-evaluate event-free survival (EFS) and overall survival (OS). RESULTS: One-hundred thirteen patients were randomized to the RT/TMZ arm (n = 54) or the RT/TMZ+BEV (BEV arm; n = 59). The tumor arose in the cerebral hemispheres in 68 patients (Cerebral group) and a midline location in 45 cases (Midline group). Pathologic diagnosis was available in all cases and molecular data in 86 of 113. H3 K27M histone mutations were present in 23 of 32 Midline cases and H3 G34R/V mutations in 7 of 54 Cerebral cases. Total/near-total resection occurred in 44 of 68 (65%) Cerebral cases but in only 5 of 45 (11%) Midline cases (P < 0.05). Leptomeningeal metastases (27 cases, 13 with subependymal spread) at relapse were more frequent in Midline (17/45) than in Cerebral tumors (10/68, P < 0.05). Mean OS (14.1 months) and EFS (9.0 months) in Midline tumors were significantly lower than mean OS (20.7 months) and EFS (14.9 months) in Cerebral tumors (P < 0.05). Pseudoprogression occurred in 8 of 111 (6.2%) cases. CONCLUSIONS: This study has shown that the poor outcome of midline tumors (compared with cerebral) may be related to (1) lesser surgical resection, (2) H3 K27M histone mutations, and (3) higher leptomeningeal dissemination.

Accelerating Pediatric Cancer Drug Development: Challenges and Opportunities for Pediatric Master Protocols.

Although outcomes for children with cancer have significantly improved over the past 40 years, there has been little progress in the treatment of some pediatric cancers, particularly when advanced. Additionally, clinical trial options and availability are often insufficient. Improved genomic and immunologic understanding of pediatric cancers, combined with innovative clinical trial designs, may provide an enhanced opportunity to study childhood cancers. Master protocols, which incorporate the use of precision medicine approaches, coupled with the ability to quickly assess the safety and effectiveness of new therapies, have the potential to accelerate early-phase clinical testing of novel therapeutics and which may result in more rapid approval of new drugs for children with cancer. Designing and conducting master protocols for children requires addressing similar principles and requirements as traditional adult oncology trials, but there are also unique considerations for master protocols conducted in children with cancer. The purpose of this paper is to define the key challenges and opportunities associated with this approach in order to ensure that master protocols can be adapted to benefit children and adolescents and ensure that adequate data are captured to advance, in parallel, the clinical development of investigational agents for children with cancer.

Deep learning using tumor HLA peptide mass spectrometry datasets improves neoantigen identification.

Neoantigens, which are expressed on tumor cells, are one of the main targets of an effective antitumor T-cell response. Cancer immunotherapies to target neoantigens are of growing interest and are in early human trials, but methods to identify neoantigens either require invasive or difficult-to-obtain clinical specimens, require the screening of hundreds to thousands of synthetic peptides or tandem minigenes, or are only relevant to specific human leukocyte antigen (HLA) alleles. We apply deep learning to a large (N = 74 patients) HLA peptide and genomic dataset from various human tumors to create a computational model of antigen presentation for neoantigen prediction. We show that our model, named EDGE, increases the positive predictive value of HLA antigen prediction by up to ninefold. We apply EDGE to enable identification of neoantigens and neoantigen-reactive T cells using routine clinical specimens and small numbers of synthetic peptides for most common HLA alleles. EDGE could enable an improved ability to develop neoantigen-targeted immunotherapies for cancer patients.

New Business Models to Accelerate Innovation in Pediatric Oncology Therapeutics: A Review.

Importance: Few patient populations are as helpless and in need of advocacy as children with cancer. Pharmaceutical companies have historically faced significant financial disincentives to pursue pediatric oncology therapeutics, including low incidence, high costs of conducting pediatric trials, and a lack of funding for early-stage research. Observations: Review of published studies of pediatric oncology research and the cost of drug development, as well as clinical trials of pediatric oncology therapeutics at ClinicalTrials.gov, identified 77 potential drug development projects to be included in a hypothetical portfolio. The returns of this portfolio were simulated so as to compute the financial returns and risk. Simulated business strategies include combining projects at different clinical phases of development, obtaining partial funding from philanthropic grants, and obtaining government guarantees to reduce risk. The purely private-sector portfolio exhibited expected returns ranging from -24.2% to 10.2%, depending on the model variables assumed. This finding suggests significant financial disincentives for pursuing pediatric oncology therapeutics and implies that financial support from the public and philanthropic sectors is essential. Phase diversification increases the likelihood of a successful drug and yielded expected returns of -5.3% to 50.1%. Standard philanthropic grants had a marginal association with expected returns, and government guarantees had a greater association by reducing downside exposure. An assessment of a proposed venture philanthropy fund demonstrated stronger performance than the purely private-sector-funded portfolio or those with traditional amounts of philanthropic support. Clinical Relevance: A combination of financial and business strategies has the potential to maximize expected return while eliminating some downside risk-in certain cases enabling expected returns as high as 50.1%-that can overcome current financial disincentives and accelerate the development of pediatric oncology therapeutics.

Phase II, Open-Label, Randomized, Multicenter Trial (HERBY) of Bevacizumab in Pediatric Patients With Newly Diagnosed High-Grade Glioma.

Purpose Bevacizumab (BEV) is approved in more than 60 countries for use in adults with recurrent glioblastoma. We evaluated the addition of BEV to radiotherapy plus temozolomide (RT+TMZ) in pediatric patients with newly diagnosed high-grade glioma (HGG). Methods The randomized, parallel group, multicenter, open-label HERBY trial ( ClinicalTrials.gov identifier: NCT01390948) enrolled patients age ≥ 3 years to ≤ 18 years with localized, centrally neuropathology-confirmed, nonbrainstem HGG. Eligible patients were randomly assigned to receive RT + TMZ (RT: 1.8 Gy, 5 days per week, and TMZ: 75 mg/m2 per day for 6 weeks; 4-week treatment break; then up to 12 × 28-day cycles of TMZ [cycle 1: 150 mg/m2 per day, days 1 to 5; cycles 2 to 12: 200 mg/m2 per day, days 1 to 5]) with or without BEV (10 mg/kg every 2 weeks). The primary end point was event-free survival (EFS) as assessed by a central radiology review committee that was blinded to treatment. We report findings of EFS at 12 months after the enrollment of the last patient. Results One hundred twenty-one patients were enrolled (RT+TMZ [n = 59]; BEV plus RT+TMZ [n = 62]). Central radiology review committee-assessed median EFS did not differ significantly between treatment groups (RT+TMZ, 11.8 months; 95% CI, 7.9 to 16.4 months; BEV plus RT+TMZ, 8.2 months; 95% CI, 7.8 to 12.7 months; hazard ratio, 1.44; P = .13 [stratified log-rank test]). In the overall survival analysis, the addition of BEV did not reduce the risk of death (hazard ratio, 1.23; 95% CI, 0.72 to 2.09). More patients in the BEV plus RT+TMZ group versus the RT+TMZ group experienced one or more serious adverse events (n = 35 [58%] v n = 27 [48%]), and more patients who received BEV discontinued study treatment as a result of adverse events (n = 13 [22%] v n = 3 [5%]). Conclusion Adding BEV to RT+TMZ did not improve EFS in pediatric patients with newly diagnosed HGG. Our findings were not comparable to those of previous adult trials, which highlights the importance of performing pediatric-specific studies.

Multi-criteria Decision Analysis to Model Ixodes ricinus Habitat Suitability.

Tick-borne diseases present a major threat to both human and livestock health throughout Europe. The risk of infection is directly related to the presence of its vector. Thereby it is important to know their distribution, which is strongly associated with environmental factors: the presence and availability of a suitable habitat, of a suitable climate and of hosts. The present study models the habitat suitability for Ixodes ricinus in Ireland, where data on tick distribution are scarce. Tick habitat suitability was estimated at a coarse scale (10 km) with a multi-criteria decision analysis (MCDA) method according to four different scenarios (depending on the variables used and on the weights granted to each of them). The western part of Ireland and the Wicklow mountains in the East were estimated to be the most suitable areas for I. ricinus in the island. There was a good level of agreement between results from the MCDA and recorded tick presence. The different scenarios did not affect the spatial outputs substantially. The current study suggests that tick habitat suitability can be mapped accurately at a coarse scale in a data-scarce context using knowledge-based methods. It can serve as a guideline for future countrywide sampling that would help to determine local risk of tick presence and refining knowledge on tick habitat suitability in Ireland.

Halotolerant bioanodes: The applied potential modulates the electrochemical characteristics, the biofilm structure and the ratio of the two dominant genera.

The development of economically-efficient microbial electrochemical technologies remains hindered by the low ionic conductivity of the culture media used as the electrolyte. To overcome this drawback, halotolerant bioanodes were designed with salt marsh sediment used as the inoculum in electrolytes containing NaCl at 30 or 45g/L (ionic conductivity 7.0 or 10.4S·m(-1)). The bioanodes were formed at four different potentials -0.4, -0.2, 0.0 and 0.2V/SCE to identify the effect on the electrochemical kinetic parameters, the biofilm structures and the composition of the microbial communities. The bioanodes formed at -0.4V/SCE were largely dominated by Marinobacter spp. Voltammetry showed that they provided higher currents than the other bioanodes in the range of low potentials, but the maximum currents were limited by the poor surface colonization. The bioanodes formed at -0.2, 0.0 and 0.2V/SCE showed similar ratios of Marinobacter and Desulfuromonas spp. and higher values of the maximum current density. The combined analysis of kinetic parameters, biofilm structure and biofilm composition showed that Marinobacter spp., which ensured a higher electron transfer rate, were promising species for the design of halotolerant bioanodes. The challenge is now to overcome its limited surface colonization in the absence of Desulfuromonas spp.

Implementation of mechanism of action biology-driven early drug development for children with cancer.

An urgent need remains for new paediatric oncology drugs to cure children who die from cancer and to reduce drug-related sequelae in survivors. In 2007, the European Paediatric Regulation came into law requiring industry to create paediatric drug (all types of medicinal products) development programmes alongside those for adults. Unfortunately, paediatric drug development is still largely centred on adult conditions and not a mechanism of action (MoA)-based model, even though this would be more logical for childhood tumours as these have much fewer non-synonymous coding mutations than adult malignancies. Recent large-scale sequencing by International Genome Consortium and Paediatric Cancer Genome Project has further shown that the genetic and epigenetic repertoire of driver mutations in specific childhood malignancies differs from more common adult-type malignancies. To bring about much needed change, a Paediatric Platform, ACCELERATE, was proposed in 2013 by the Cancer Drug Development Forum, Innovative Therapies for Children with Cancer, the European Network for Cancer Research in Children and Adolescents and the European Society for Paediatric Oncology. The Platform, comprising multiple stakeholders in paediatric oncology, has three working groups, one with responsibility for promoting and developing high-quality MoA-informed paediatric drug development programmes, including specific measures for adolescents. Key is the establishment of a freely accessible aggregated database of paediatric biological tumour drug targets to be aligned with an aggregated pipeline of drugs. This will enable prioritisation and conduct of early phase clinical paediatric trials to evaluate these drugs against promising therapeutic targets and to generate clinical paediatric efficacy and safety data in an accelerated time frame. Through this work, the Platform seeks to ensure that potentially effective drugs, where the MoA is known and thought to be relevant to paediatric malignancies, are evaluated in early phase clinical trials, and that this approach to generate pre-clinical and clinical data is systematically pursued by academia, sponsors, industry, and regulatory bodies to bring new paediatric oncology drugs to front-line therapy more rapidly.

In Vitro and In Vivo Comparison of Lymphocytes Transduced with a Human CD16 or with a Chimeric Antigen Receptor Reveals Potential Off-Target Interactions due to the IgG2 CH2-CH3 CAR-Spacer.

The present work was designed to compare two mechanisms of cellular recognition based on Ab specificity: firstly, when the anti-HER2 mAb trastuzumab bridges target cells and cytotoxic lymphocytes armed with a Fc receptor (ADCC) and, secondly, when HER2 positive target cells are directly recognized by cytotoxic lymphocytes armed with a chimeric antigen receptor (CAR). To compare these two mechanisms, we used the same cellular effector (NK-92) and the same signaling domain (FcεRIγ). The NK-92 cytotoxic cell line was transfected with either a FcγRIIIa-FcεRIγ (NK-92(CD16)) or a trastuzumab-based scFv-FcεRIγ chimeric receptor (NK-92(CAR)). In vitro, the cytotoxic activity against HER2 positive target cells after indirect recognition by NK-92(CD16) was always inferior to that observed after direct recognition by NK-92(CAR). In contrast, and somehow unexpectedly, in vivo, adoptive transfer of NK-92(CD16) + trastuzumab but not of NK-92(CAR) induced tumor regression. Analysis of the in vivo xenogeneic system suggested that the human CH2-CH3 IgG2 used as a spacer in our construct was able to interact with the FcR present at the cell surface of the few NSG-FcR+ remaining immune cells. This interaction, leading to blockage of the NK-92(CAR) in the periphery of the engrafted tumor cells, stresses the critical role of the composition of the spacer domain.

Electrochemical characterization of microbial bioanodes formed on a collector/electrode system in a highly saline electrolyte.

Bioanodes were formed with electrodes made of carbon felt and equipped with a titanium electrical collector, as commonly used in microbial fuel cells. Electrochemical impedance spectroscopy (EIS) performed on the abiotic electrode system evidenced two time constants, one corresponding to the "collector/carbon felt" contact, the other to the "carbon felt/solution" interface. Such a two time constant system was characteristics of the two-material electrode, independent of biofilm presence. EIS was then performed during the bioanode formation around the constant applied potential of 0.1 V/SCE. The equivalent electrical model was similar to that of the abiotic system. Due to the high salinity of the electrolyte (45 g·L(-1) NaCl) the electrolyte resistance was always very low. The bioanode development induced kinetic heterogeneities that were taken into account by replacing the pure capacitance of the abiotic system by a constant phase element for the "carbon felt/solution" interface. The current increase from 0 to 20.6 A·m(-2) was correlated to the considerable decrease of the charge transfer resistance of the "carbon felt/solution" interface from 2.4 10(4) to 92 Ω·cm(2). Finally, EIS implemented at 0.4 V/SCE showed that the limitation observed at high potential values was not related to mass transfer but to a biofilm-linked kinetics.

Pre-clinical evaluation of the MDM2-p53 antagonist RG7388 alone and in combination with chemotherapy in neuroblastoma.

Neuroblastoma is a predominantly p53 wild-type (wt) tumour and MDM2-p53 antagonists offer a novel therapeutic strategy for neuroblastoma patients. RG7388 (Roche) is currently undergoing early phase clinical evaluation in adults. This study assessed the efficacy of RG7388 as a single-agent and in combination with chemotherapies currently used to treat neuroblastoma in a panel of neuroblastoma cell lines. RG7388 GI50 concentrations were determined in 21 p53-wt and mutant neuroblastoma cell lines of varying MYCN, MDM2 and p14(ARF) status, together with MYCN-regulatable Tet21N cells. The primary determinant of response was the presence of wt p53, and overall there was a >200-fold difference in RG7388 GI50 concentrations for p53-wt versus mutant cell lines. Tet21N MYCN+ cells were significantly more sensitive to RG7388 compared with MYCN- cells. Using median-effect analysis in 5 p53-wt neuroblastoma cell lines, selected combinations of RG7388 with cisplatin, doxorubicin, topotecan, temozolomide and busulfan were synergistic. Furthermore, combination treatments led to increased apoptosis, as evident by higher caspase-3/7 activity compared to either agent alone. These data show that RG7388 is highly potent against p53-wt neuroblastoma cells, and strongly supports its further evaluation as a novel therapy for patients with high-risk neuroblastoma and wt p53 to potentially improve survival and/or reduce toxicity.

Creating a unique, multi-stakeholder Paediatric Oncology Platform to improve drug development for children and adolescents with cancer.

Seven years after the launch of the European Paediatric Medicine Regulation, limited progress in paediatric oncology drug development remains a major concern amongst stakeholders - academics, industry, regulatory authorities, parents, patients and caregivers. Restricted increases in early phase paediatric oncology trials, legal requirements and regulatory pressure to propose early Paediatric Investigation Plans (PIPs), missed opportunities to explore new drugs potentially relevant for paediatric malignancies, lack of innovative trial designs and no new incentives to develop drugs against specific paediatric targets are some unmet needs. Better access to new anti-cancer drugs for paediatric clinical studies and improved collaboration between stakeholders are essential. The Cancer Drug Development Forum (CDDF), previously Biotherapy Development Association (BDA), with Innovative Therapy for Children with Cancer Consortium (ITCC), European Society for Paediatric Oncology (SIOPE) and European Network for Cancer Research in Children and Adolescents (ENCCA) has created a unique Paediatric Oncology Platform, involving multiple stakeholders and the European Union (EU) Commission, with an urgent remit to improve paediatric oncology drug development. The Paediatric Oncology Platform proposes to recommend immediate changes in the implementation of the Regulation and set the framework for its 2017 revision; initiatives to incentivise drug development against specific paediatric oncology targets, and repositioning of drugs not developed in adults. Underpinning these changes is a strategy for mechanism of action and biology driven selection and prioritisation of potential paediatric indications rather than the current process based on adult cancer indications. Pre-competitive research and drug prioritisation, early portfolio evaluation, cross-industry cooperation and multi-compound/sponsor trials are being explored, from which guidance for innovative trial designs will be provided.

Modelling potential/current distribution in microbial electrochemical systems shows how the optimal bioanode architecture depends on electrolyte conductivity.

The theoretical bases for modelling the distribution of the electrostatic potential in microbial electrochemical systems are described. The secondary potential distribution (i.e. without mass transport limitation of the substrate) is shown to be sufficient to validly address microbial electrolysis cells (MECs). MECs are modelled with two different ionic conductivities of the solution (1 and 5.3 S m(-1)) and two bioanode kinetics (jmax = 5.8 or 34 A m(-2)). A conventional reactor configuration, with the anode and the cathode face to face, is compared with a configuration where the bioanode perpendicular to the cathode implements the electrochemical reaction on its two sides. The low solution conductivity is shown to have a crucial impact, which cancels out the advantages obtained by setting the bioanode perpendicular to the cathode. For the same reason, when the surface area of the anode is increased by multiplying the number of plates, care must be taken not to create too dense anode architecture. Actually, the advantages of increasing the surface area by multiplying the number of plates can be lost through worsening of the electrochemical conditions in the multi-layered anode, because of the increase of the electrostatic potential of the solution inside the anode structure. The model gives the first theoretical bases for scaling up MECs in a rather simple but rigorous way.

Anti-MDR1 siRNA restores chemosensitivity in chemoresistant breast carcinoma and osteosarcoma cell lines.

BACKGROUND: Reversion of chemoresistance by inhibition of P-glycoprotein (P-gp) expression may overcome the chemoresistance observed in many cancer types and may allow for improved therapeutic ratio. We investigated whether siRNA specific for ABCB1 (MDR1) mRNA might restore sensitivity to chemotherapy in tumor cell lines known to overexpress the MDR1 gene. MATERIALS AND METHODS: MDR1-expressing tumor cell lines were transiently transfected with anti-MDR1 silencing RNA (siRNA) before exposure to doxorubicin or methotrexate. The capacity of siRNA to reduce cell proliferation and increase the IC50 of the tested chemotherapies was investigated. RESULTS: siRNA down-regulated MDR1 mRNA expression by 50% in breast carcinoma and osteosarcoma cell lines, and significantly inhibited tumor cell proliferation up to 90% (p<0.01), when co-administered with doxorubicin or methotrexate, despite the known chemoresistance of the cell lines. siRNAs reduced the IC50 of doxorubicin and methotrexate by more than 10-fold (p<0.01). CONCLUSION: These results suggest the potential clinical application of anti-MDR1 siRNA to restore chemosensitivity and possibly improve the therapeutic ratio of these cytotoxic drugs.