Microglia Require CD4 T Cells to Complete the Fetal-to-Adult Transition.

The brain is a site of relative immune privilege. Although CD4 T cells have been reported in the central nervous system, their presence in the healthy brain remains controversial, and their function remains largely unknown. We used a combination of imaging, single cell, and surgical approaches to identify a CD69+ CD4 T cell population in both the mouse and human brain, distinct from circulating CD4 T cells. The brain-resident population was derived through in situ differentiation from activated circulatory cells and was shaped by self-antigen and the peripheral microbiome. Single-cell sequencing revealed that in the absence of murine CD4 T cells, resident microglia remained suspended between the fetal and adult states. This maturation defect resulted in excess immature neuronal synapses and behavioral abnormalities. These results illuminate a role for CD4 T cells in brain development and a potential interconnected dynamic between the evolution of the immunological and neurological systems. VIDEO ABSTRACT.

Astrocyte-targeted gene delivery of interleukin 2 specifically increases brain-resident regulatory T cell numbers and protects against pathological neuroinflammation.

The ability of immune-modulating biologics to prevent and reverse pathology has transformed recent clinical practice. Full utility in the neuroinflammation space, however, requires identification of both effective targets for local immune modulation and a delivery system capable of crossing the blood-brain barrier. The recent identification and characterization of a small population of regulatory T (Treg) cells resident in the brain presents one such potential therapeutic target. Here, we identified brain interleukin 2 (IL-2) levels as a limiting factor for brain-resident Treg cells. We developed a gene-delivery approach for astrocytes, with a small-molecule on-switch to allow temporal control, and enhanced production in reactive astrocytes to spatially direct delivery to inflammatory sites. Mice with brain-specific IL-2 delivery were protected in traumatic brain injury, stroke and multiple sclerosis models, without impacting the peripheral immune system. These results validate brain-specific IL-2 gene delivery as effective protection against neuroinflammation, and provide a versatile platform for delivery of diverse biologics to neuroinflammatory patients.

The tissue-resident regulatory T cell pool is shaped by transient multi-tissue migration and a conserved residency program.

The tissues are the site of many important immunological reactions, yet how the immune system is controlled at these sites remains opaque. Recent studies have identified Foxp3+ regulatory T (Treg) cells in non-lymphoid tissues with unique characteristics compared with lymphoid Treg cells. However, tissue Treg cells have not been considered holistically across tissues. Here, we performed a systematic analysis of the Treg cell population residing in non-lymphoid organs throughout the body, revealing shared phenotypes, transient residency, and common molecular dependencies. Tissue Treg cells from different non-lymphoid organs shared T cell receptor (TCR) sequences, with functional capacity to drive multi-tissue Treg cell entry and were tissue-agnostic on tissue homing. Together, these results demonstrate that the tissue-resident Treg cell pool in most non-lymphoid organs, other than the gut, is largely constituted by broadly self-reactive Treg cells, characterized by transient multi-tissue migration. This work suggests common regulatory mechanisms may allow pan-tissue Treg cells to safeguard homeostasis across the body.

In situ tumour arrays reveal early environmental control of cancer immunity.

The immune phenotype of a tumour is a key predictor of its response to immunotherapy1-4. Patients who respond to checkpoint blockade generally present with immune-inflamed5-7 tumours that are highly infiltrated by T cells. However, not all inflamed tumours respond to therapy, and even lower response rates occur among tumours that lack T cells (immune desert) or that spatially exclude T cells to the periphery of the tumour lesion (immune excluded)8. Despite the importance of these tumour immune phenotypes in patients, little is known about their development, heterogeneity or dynamics owing to the technical difficulty of tracking these features in situ. Here we introduce skin tumour array by microporation (STAMP)-a preclinical approach that combines high-throughput time-lapse imaging with next-generation sequencing of tumour arrays. Using STAMP, we followed the development of thousands of arrayed tumours in vivo to show that tumour immune phenotypes and outcomes vary between adjacent tumours and are controlled by local factors within the tumour microenvironment. Particularly, the recruitment of T cells by fibroblasts and monocytes into the tumour core was supportive of T cell cytotoxic activity and tumour rejection. Tumour immune phenotypes were dynamic over time and an early conversion to an immune-inflamed phenotype was predictive of spontaneous or therapy-induced tumour rejection. Thus, STAMP captures the dynamic relationships of the spatial, cellular and molecular components of tumour rejection and has the potential to translate therapeutic concepts into successful clinical strategies.

Multitask Deep Neural Networks for Ames Mutagenicity Prediction.

The Ames mutagenicity test constitutes the most frequently used assay to estimate the mutagenic potential of drug candidates. While this test employs experimental results using various strains of Salmonella typhimurium, the vast majority of the published in silico models for predicting mutagenicity do not take into account the test results of the individual experiments conducted for each strain. Instead, such QSAR models are generally trained employing overall labels (i.e., mutagenic and nonmutagenic). Recently, neural-based models combined with multitask learning strategies have yielded interesting results in different domains, given their capabilities to model multitarget functions. In this scenario, we propose a novel neural-based QSAR model to predict mutagenicity that leverages experimental results from different strains involved in the Ames test by means of a multitask learning approach. To the best of our knowledge, the modeling strategy hereby proposed has not been applied to model Ames mutagenicity previously. The results yielded by our model surpass those obtained by single-task modeling strategies, such as models that predict the overall Ames label or ensemble models built from individual strains. For reproducibility and accessibility purposes, all source code and datasets used in our experiments are publicly available.

Improving patient selection for immuno-oncology phase 1 trials: External validation of six prognostic scores in a French Cancer Center.

We compared the performance of six prognostic scores (Royal Marsden Hospital, MDACC: MD Anderson Clinical Center and MDACC + NLR: neutrophil-to-lymphocyte ratio, MD Anderson - immune checkpoint inhibitors (MDA-ICI), GRIm: Gustave Roussy Immune Score and LIPI: Lung Immune Prognostic Index) in predicting overall survival (OS) in phase I trial patients treated with immune checkpoint inhibitors (ICI). Medical records of patients with advanced solid tumors enrolled in ICI phase I trials between 2015 and 2018 at Institut Universitaire du Cancer de Toulouse-Oncopole were reviewed. The performance of prognostic scores on OS was compared using different criteria. A total of 259 patients were included. Median age was 63 years (range: 18-83). Main primary cancers were melanoma (19%), head and neck (16%), lung (13%) and bladder (10%). With a median follow-up of 15 months (95% confidence interval [CI] = [11.6;17.5]), median OS was 12.5 months (95% CI = [10.3;16.0]). All scores were associated with OS. The MDACC, LIPI and GRIm scores performed better than the others. Concordance of risk group assignment between the scoring systems was poor. According to our results, the MDACC, GRIm and LIPI scores better suited to ICI phase I settings. Adequate scoring would allow better patient selection in early ICI trials, especially during the critical period of dose escalation, and in proof-of-concept expansion cohorts.

Murine myeloproliferative disorder as a consequence of impaired collaboration between dendritic cells and CD4 T cells.

Dendritic cells (DCs) are a key cell type in the initiation of the adaptive immune response. Recently, an additional role for DCs in suppressing myeloproliferation was discovered. Myeloproliferative disorder (MPD) was observed in murine studies with constitutive depletion of DCs, as well as in patients with congenital deficiency in DCs caused by mutations in GATA2 or IRF8 The mechanistic link between DC deficiency and MPD was not predicted through the known biology and has remained an enigma. Prevailing models suggest numerical DC deficiency leads to MPD through compensatory myeloid differentiation. Here, we formally tested whether MPD can also arise through a loss of DC function without numerical deficiency. Using mice whose DCs are deficient in antigen presentation, we find spontaneous MPD that is characterized by splenomegaly, neutrophilia, and extramedullary hematopoiesis, despite normal numbers of DCs. Disease development was dependent on loss of the MHC class II (MHCII) antigen-presenting complex on DCs and was eliminated in mice deficient in total lymphocytes. Mice lacking MHCII and CD4 T cells did not develop disease. Thus, MPD was paradoxically contingent on the presence of CD4 T cells and on a failure of DCs to activate CD4 T cells, trapping the cells in a naive Flt3 ligand-expressing state. These results identify a novel requirement for intercellular collaboration between DCs and CD4 T cells to regulate myeloid differentiation. Our findings support a new conceptual framework of DC biology in preventing MPD in mice and humans.

AI in drug development: a multidisciplinary perspective.

The introduction of a new drug to the commercial market follows a complex and long process that typically spans over several years and entails large monetary costs due to a high attrition rate. Because of this, there is an urgent need to improve this process using innovative technologies such as artificial intelligence (AI). Different AI tools are being applied to support all four steps of the drug development process (basic research for drug discovery; pre-clinical phase; clinical phase; and postmarketing). Some of the main tasks where AI has proven useful include identifying molecular targets, searching for hit and lead compounds, synthesising drug-like compounds and predicting ADME-Tox. This review, on the one hand, brings in a mathematical vision of some of the key AI methods used in drug development closer to medicinal chemists and, on the other hand, brings the drug development process and the use of different models closer to mathematicians. Emphasis is placed on two aspects not mentioned in similar surveys, namely, Bayesian approaches and their applications to molecular modelling and the eventual final use of the methods to actually support decisions. Promoting a perfect synergy.

From presentation to paper: Gender disparities in oncological research.

Gender disparities in scientific publications have been identified in oncological research. Oral research presentations at major conferences enhance visibility of presenters. The share of women presenting at such podia is unknown. We aim to identify gender-based differences in contributions to presentations at two major oncological conferences. Abstracts presented at plenary sessions of the American Society of Clinical Oncology (ASCO) Annual Meetings and European Society for Medical Oncology (ESMO) Congresses were collected. Trend analyses were used to analyze female contribution over time. The association between presenter's sex, study outcome (positive/negative) and journals' impact factors (IFs) of subsequently published papers was assessed using Chi-square and Mann-Whitney U tests. Of 166 consecutive abstracts presented at ASCO in 2011-2018 (n = 34) and ESMO in 2008-2018 (n = 132), 21% had female presenters, all originating from Northern America (n = 17) or Europe (n = 18). The distribution of presenter's sex was similar over time (p = 0.70). Of 2,425 contributing authors to these presented abstracts, 28% were women. The proportion of female abstract authors increased over time (p < 0.05) and was higher in abstracts with female (34%) compared to male presenters (26%; p < 0.01). Presenter's sex was not associated with study outcome (p = 0.82). Median journals' IFs were lower in papers with a female first author (p < 0.05). In conclusion, there is a clear gender disparity in research presentations at two major oncological conferences, with 28% of authors and 21% of presenters of these studies being female. Lack of visibility of female presenters could impair acknowledgement for their research, opportunities in their academic career and even hamper heterogeneity in research.

Phase 1 study of the immunotoxin LMB-100 in patients with mesothelioma and other solid tumors expressing mesothelin.

BACKGROUND: LMB-100 is an antibody-toxin conjugate with an antimesothelin Fab linked to a 24-kilodalton portion of Pseudomonas exotoxin A with mutations that decrease immunogenicity. The objective of the current first-in-human phase 1 study was to determine the maximum tolerated dose (MTD) and safety in patients with advanced solid tumors expressing mesothelin. METHODS: Cohorts of 1 to 7 patients received intravenous LMB-100 at 7 dose levels from 40 µg/kg to 250 µg/kg intravenously on days 1, 3, and 5 of a 21-day cycle. RESULTS: Of the 25 patients accrued, 17 had mesothelioma, 3 each had ovarian or pancreatic cancer, and 2 patients had gastric cancer. Dose-limiting toxicities occurred in 2 of 4 patients treated at a dose of 250 µg/kg (capillary leak syndrome) and in 3 of 7 patients treated at a dose of 170 µg/kg (creatinine increase). The MTD of LMB-100 was 140 µg/kg. Of the 10 patients with mesothelioma who were treated at doses of 170 µg/kg or 140 µg/kg, 8 had stable disease and 2 developed progressive disease. Peak LMB-100 plasma concentrations were dose-dependent during cycle 1. The development of antidrug antibodies decreased LMB-100 blood levels in 8 of 21 patients (38%) who received cycle 2 and 9 of 11 patients (81.8%) who received cycle 3. CONCLUSIONS: The MTD for single-agent LMB-100 was found to be 140 µg/kg given on a schedule of every other day for 3 doses every 3 weeks. Although less immunogenic than the first-generation antimesothelin immunotoxin SS1P, the majority of patients developed antidrug antibodies after 2 cycles, indicating that LMB-100 has limited antitumor efficacy as a single agent. Phase 2 studies of LMB-100 plus pembrolizumab currently are ongoing for patients with mesothelioma and lung cancer. LAY SUMMARY: Mesothelin, a cell surface antigen, is an attractive target for cancer therapy given its limited expression in normal human tissues and high expression in many human cancers. LMB-100 is a recombinant antimesothelin immunotoxin consisting of a humanized antimesothelin antibody fragment fused to a truncated Pseudomonas exotoxin A. In the current study, the authors determined the safety, maximum tolerated dose, and pharmacokinetics of LMB-100, as well as the generation of antidrug antibodies. Ongoing phase 2 clinical trials are evaluating the combination of LMB-100 plus pembrolizumab in patients with treatment-refractory mesothelioma and non-small cell lung cancer.

A Phase 1 dose-escalation study to evaluate safety, pharmacokinetics and pharmacodynamics of AsiDNA, a first-in-class DNA repair inhibitor, administered intravenously in patients with advanced solid tumours.

BACKGROUND: AsiDNA, a first-in-class oligonucleotide-mimicking double-stranded DNA breaks, acts as a decoy agonist to DNA damage response in tumour cells. It also activates DNA-dependent protein kinase and poly (adenosine diphosphate [ADP]-ribose) polymerase enzymes that induce phosphorylation of H2AX and protein PARylation. METHODS: The aim of this Phase 1 study was to determine dose-limiting toxicities (DLTs), maximum tolerated dose (MTD), safety and pharmacokinetics/pharmacodynamics of AsiDNA administered daily for 3 days in the first week then weekly thereafter. Twenty-two patients with advanced solid tumours were enrolled in 5 dose levels: 200, 400, 600, 900, and 1300 mg, using a 3 + 3 design. RESULTS: The MTD was not reached. IV AsiDNA was safe. Two DLTs (grade 4 and grade 3 hepatic enzymes increased at 900 and 1300 mg), and two related SAE at 900 mg (grade 3 hypotension and grade 4 hepatic enzymes increased) were reported. AsiDNA PK increased proportionally with dose. A robust activation of DNA-PK by a significant posttreatment increase of γH2AX was evidenced in tumour biopsies. CONCLUSION: The dose of 600 mg was identified as the optimal dose for further clinical development. CLINICAL TRIAL REGISTRATION: Clinical trial registration (NCT number): NCT03579628.

Modernizing adverse events analysis in oncology clinical trials using alternative approaches: rationale and design of the MOTIVATE trial.

In oncology clinical research, the analysis and reporting of adverse events is of major interest. A consistent depiction of the safety profile of a new treatment is as crucial in establishing how to use it as its antitumor activity. The advent of new therapeutics has led to major changes in the management of patients and targeted therapies or immune checkpoint inhibitors are administered continuously for months or even years. However, the classical methods of adverse events analysis are no longer adequate to properly assess their safety profile. Indeed, the worst grade method and time-to-event analysis cannot capture the duration or the evolution of adverse events induced by extended treatment durations. Many authors have highlighted this issue and argue that the analysis of safety data from clinical trials should be modernized by considering the dimension of time and the recurrent nature of adverse events. This paper aims to illustrate the limitations of current methods and discusses the value of alternative approaches such as the prevalence function, Q-TWiST, the ToxT and the recurrent event approaches. The rationale and design of the MOTIVATE trial, which aims to model the evolution of toxicities over time using the prevalence function in patients treated by immunotherapy, is also presented ( ClinicalTrials.gov Identifier: NCT03447483; Date of registration: 27 February 2018).

Machine learning identifies an immunological pattern associated with multiple juvenile idiopathic arthritis subtypes.

OBJECTIVES: Juvenile idiopathic arthritis (JIA) is the most common class of childhood rheumatic diseases, with distinct disease subsets that may have diverging pathophysiological origins. Both adaptive and innate immune processes have been proposed as primary drivers, which may account for the observed clinical heterogeneity, but few high-depth studies have been performed. METHODS: Here we profiled the adaptive immune system of 85 patients with JIA and 43 age-matched controls with indepth flow cytometry and machine learning approaches. RESULTS: Immune profiling identified immunological changes in patients with JIA. This immune signature was shared across a broad spectrum of childhood inflammatory diseases. The immune signature was identified in clinically distinct subsets of JIA, but was accentuated in patients with systemic JIA and those patients with active disease. Despite the extensive overlap in the immunological spectrum exhibited by healthy children and patients with JIA, machine learning analysis of the data set proved capable of discriminating patients with JIA from healthy controls with ~90% accuracy. CONCLUSIONS: These results pave the way for large-scale immune phenotyping longitudinal studies of JIA. The ability to discriminate between patients with JIA and healthy individuals provides proof of principle for the use of machine learning to identify immune signatures that are predictive to treatment response group.

NFIL3 mutations alter immune homeostasis and sensitise for arthritis pathology.

OBJECTIVES: NFIL3 is a key immunological transcription factor, with knockout mice studies identifying functional roles in multiple immune cell types. Despite the importance of NFIL3, little is known about its function in humans. METHODS: Here, we characterised a kindred of two monozygotic twin girls with juvenile idiopathic arthritis at the genetic and immunological level, using whole exome sequencing, single cell sequencing and flow cytometry. Parallel studies were performed in a mouse model. RESULTS: The patients inherited a novel p.M170I in NFIL3 from each of the parents. The mutant form of NFIL3 demonstrated reduced stability in vitro. The potential contribution of this mutation to arthritis susceptibility was demonstrated through a preclinical model, where Nfil3-deficient mice upregulated IL-1ß production, with more severe arthritis symptoms on disease induction. Single cell sequencing of patient blood quantified the transcriptional dysfunctions present across the peripheral immune system, converging on IL-1ß as a pivotal cytokine. CONCLUSIONS: NFIL3 mutation can sensitise for arthritis development, in mice and humans, and rewires the innate immune system for IL-1ß over-production.

First-in-human phase I study of the microtubule inhibitor plocabulin in patients with advanced solid tumors.

Background Plocabulin (PM060184) is a novel marine-derived microtubule inhibitor that acts as an antitumor agent. This first-in-human study evaluated dose-limiting toxicities (DLT) to define the maximum tolerated dose (MTD) and phase II recommended dose (RD) of plocabulin given as a 10-min infusion on Day (D) 1, D8 and D15 every four weeks. Patients and methods Forty-four patients with advanced solid tumors received plocabulin following an accelerated titration design. Results Plocabulin was escalated from 1.3 mg/m2 to 14.5 mg/m2, which was defined as the MTD. No RD was confirmed, because frequent dose delays and omissions resulted in low relative dose intensity (66%) at the 12.0 mg/m2 expansion cohort. The main DLT was grade 3 peripheral sensory neuropathy (PSN); other DLTs were grade 4 tumor lysis syndrome, grade 4 cardiac failure and grade 3 myalgia. Toxicities were mainly mild to moderate, and included abdominal pain, myalgia, fatigue, nausea, and vomiting. Myelosuppression was transient and manageable. Plocabulin had a half-life of ~4 h and a wide diffusion to peripheral tissues. Antitumor response was observed in cervix carcinoma and heavily pretreated metastatic non-small cell lung cancer patients, and disease stabilization (≥3 months) in patients with colorectal, thymic, gastrointestinal stromal and breast tumors, among others. The clinical benefit rate was 33%. Conclusion The main DLT of plocabulin was PSN, as anticipated for a tubulin-binding agent. Since encouraging antitumor activity was observed, efforts to improve toxicity and to find the RD were planned in other trials evaluating D1&D8 and D1-D3 plus D15-D17 schedules.

Phase I dose-escalation study of F14512, a polyamine-vectorized topoisomerase II inhibitor, in patients with platinum-refractory or resistant ovarian cancer.

Purpose To determine the maximum tolerated dose (MTD) of F14512, a topoisomerase II inhibitor designed to target cancer cells through the polyamine transport system, (three-hour daily infusion given for 3 consecutive days every 3 weeks) in platinum-refractory or resistant ovarian cancer. Other objectives were safety, pharmacokinetics (PK), PK/pharmacodynamics relationship, and efficacy. Methods This was an open-label, dose-escalation, multicenter phase I study. Results Eleven patients were enrolled and were treated at dose levels (DLs) of 10 and 5 mg/m2/day. All patients received the 3 injections per cycle as per study protocol (median, 1 cycle (Ferlay et al. Int J Cancer 136:E359-386, 2015; Siegel et al. CA Cancer J Clin 65:5-29, 2015; Oronsky et al. Med Oncol 34:103, 2017; Barret et al. Cancer Res 68:9845-9853, 2008; Ballot et al. Apoptosis 17:364-376, 2012; Brel et al. Biochem Pharmacol 82:1843-1852, 2011; Gentry et al. Biochemistry 50:3240-3249, 2011; Kruczynski et al. Investig New Drugs 29:9-21, 2011; Chelouah et al. PLoS One 6:e23597, 2011)) with no dose reductions. At DL 10 mg/m2/day, 6 dose-limiting toxicities (DLTs) were reported (3/4 evaluable patients: 2 grade 3 febrile neutropenia, 1 grade 4 neutropenia lasting at least 7 days, 1 grade 3 nausea, 1 decreased appetite, and 1 grade 3 asthenia). At dose 5 mg/m2/day, 2 DLTs were reported (2/6 treated patients: 2 grade 3 febrile neutropenia). Both DLs were defined as MTD. Stable disease was reported as best overall response in 2 (40%) patients having both received 9 cycles, one at each DL. 90.9% of patients experienced grade 4 neutropenia, but for only one (9.1%) it was reported as a serious adverse event. Conclusion Although there was some encouraging efficacy signal, grade 4 neutropenia led to complications and it was decided to stop the study. A DL below 5 mg/m2/day was not tested as this would not allow reaching the minimum serum concentration needed for the pharmacological activity of the drug.

Dose-painting multicenter phase III trial in newly diagnosed glioblastoma: the SPECTRO-GLIO trial comparing arm A standard radiochemotherapy to arm B radiochemotherapy with simultaneous integrated boost guided by MR spectroscopic imaging.

BACKGROUND: Glioblastoma, a high-grade glial infiltrating tumor, is the most frequent malignant brain tumor in adults and carries a dismal prognosis. External beam radiotherapy (EBRT) increases overall survival but this is still low due to local relapses, mostly occurring in the irradiation field. As the ratio of spectra of choline/N acetyl aspartate> 2 (CNR2) on MR spectroscopic imaging has been described as predictive for the site of local relapse, we hypothesized that dose escalation on these regions would increase local control and hence global survival. METHODS/DESIGN: In this multicenter prospective phase III trial for newly diagnosed glioblastoma, 220 patients having undergone biopsy or surgery are planned for randomization to two arms. Arm A is the Stupp protocol (EBRT 60 Gy on contrast enhancement + 2 cm margin with concomitant temozolomide (TMZ) and 6 months of TMZ maintenance); Arm B is the same treatment with an additional simultaneous integrated boost of intensity-modulated radiotherapy (IMRT) of 72Gy/2.4Gy delivered on the MR spectroscopic imaging metabolic volumes of CHO/NAA > 2 and contrast-enhancing lesions or resection cavity. Stratification is performed on surgical and MGMT status. DISCUSSION: This is a dose-painting trial, i.e. delivery of heterogeneous dose guided by metabolic imaging. The principal endpoint is overall survival. An online prospective quality control of volumes and dose is performed in the experimental arm. The study will yield a large amount of longitudinal multimodal MR imaging data including planning CT, radiotherapy dosimetry, MR spectroscopic, diffusion and perfusion imaging. TRIAL REGISTRATION: NCT01507506 , registration date December 20, 2011.

From simple quinoxalines to potent oxazolo[5,4-f]quinoxaline inhibitors of glycogen-synthase kinase 3 (GSK3).

2,7-Disubstituted oxazolo[5,4-f]quinoxalines were synthesized from 6-amino-2-chloroquinoxaline in four steps (iodination at C5, substitution of the chloro group, amidation and copper-catalysed cyclization) affording 28 to 44% overall yields. 2,8-Disubstituted oxazolo[5,4-f]quinoxaline was similarly obtained from 6-amino-3-chloroquinoxaline (39% overall yield). For the synthesis of other oxazolo[5,4-f]quinoxalines, amidation was rather performed before substitution; moreover, time-consuming purification steps were avoided between the amines and the final products (38 to 54% overall yields). Finally, a more efficient method involving merging of the last two steps in a sequential process was developed to access more derivatives (37 to 65% overall yields). Most of the oxazolo[5,4-f]quinoxalines were evaluated for their activity on a panel of protein kinases, and a few 2,8-disubstituted derivatives proved to inhibit GSK3 kinase. While experiments showed an ATP-competitive inhibition on GSK3ß, structure-activity relationships allowed us to identify 2-(3-pyridyl)-8-(thiomorpholino)oxazolo[5,4-f]quinoxaline as the most potent inhibitor with an IC50 value of about 5 nM on GSK3α.

Phase I dose-escalation trial of afatinib, an irreversible ErbB family blocker, in combination with gemcitabine or docetaxel in patients with relapsed or refractory solid tumors.

Background Afatinib, an irreversible ErbB family blocker, has shown synergistic antitumor activity and manageable tolerability in combination with chemotherapy. This phase I study assessed oral afatinib plus intravenous gemcitabine or docetaxel in patients with relapsed/refractory solid tumors. Methods Patients received afatinib (30, 40, or 50 mg) plus gemcitabine (1000 or 1250 mg/m2) or docetaxel (60 or 75 mg/m2). Dose escalation proceeded via a 3 + 3 design until the maximum tolerated dose (MTD) was reached. Adverse events (AEs), pharmacokinetics and antitumor activity were also assessed. Results Dose-limiting toxicities during Cycle 1 were reported in 6/39 patients receiving afatinib/gemcitabine (most commonly diarrhea, thrombocytopenia and vomiting) and 16/54 patients receiving afatinib/docetaxel (most commonly febrile neutropenia and stomatitis). The MTDs were established as afatinib 40 mg/gemcitabine 1000 mg/m2 and afatinib 30 mg/docetaxel 60 mg/m2. The most common drug-related AEs were diarrhea, asthenia and rash with afatinib/gemcitabine, and diarrhea, asthenia and stomatitis with afatinib/docetaxel. No relevant pharmacokinetic interactions were observed for either combination. Both combinations demonstrated clinical activity and durable disease control at the MTDs. Compared with the MTD, higher response rates were achieved with afatinib 30 mg/docetaxel 75 mg/m2 (28% vs 6%); however, this regimen was associated with problematic febrile neutropenia, an expected AE with docetaxel, that is often managed with growth factor support. Conclusions Afatinib/gemcitabine and afatinib/docetaxel demonstrated manageable safety profiles, with evidence of clinical efficacy at the MTDs. For afatinib/docetaxel, a dose level of afatinib 30 mg/docetaxel 75 mg/m2 produced higher response rates. Trial registration: NCT01251653 ( ClinicalTrials.gov ).

Identification of new allosteric sites and modulators of AChE through computational and experimental tools.

Allosteric sites on proteins are targeted for designing more selective inhibitors of enzyme activity and to discover new functions. Acetylcholinesterase (AChE), which is most widely known for the hydrolysis of the neurotransmitter acetylcholine, has a peripheral allosteric subsite responsible for amyloidosis in Alzheimer's disease through interaction with amyloid ß-peptide. However, AChE plays other non-hydrolytic functions. Here, we identify and characterise using computational tools two new allosteric sites in AChE, which have allowed us to identify allosteric inhibitors by virtual screening guided by structure-based and fragment hotspot strategies. The identified compounds were also screened for in vitro inhibition of AChE and three were observed to be active. Further experimental (kinetic) and computational (molecular dynamics) studies have been performed to verify the allosteric activity. These new compounds may be valuable pharmacological tools in the study of non-cholinergic functions of AChE.