Integrated Proteogenomic Characterization across Major Histological Types of Pediatric Brain Cancer.

We report a comprehensive proteogenomics analysis, including whole-genome sequencing, RNA sequencing, and proteomics and phosphoproteomics profiling, of 218 tumors across 7 histological types of childhood brain cancer: low-grade glioma (n = 93), ependymoma (32), high-grade glioma (25), medulloblastoma (22), ganglioglioma (18), craniopharyngioma (16), and atypical teratoid rhabdoid tumor (12). Proteomics data identify common biological themes that span histological boundaries, suggesting that treatments used for one histological type may be applied effectively to other tumors sharing similar proteomics features. Immune landscape characterization reveals diverse tumor microenvironments across and within diagnoses. Proteomics data further reveal functional effects of somatic mutations and copy number variations (CNVs) not evident in transcriptomics data. Kinase-substrate association and co-expression network analysis identify important biological mechanisms of tumorigenesis. This is the first large-scale proteogenomics analysis across traditional histological boundaries to uncover foundational pediatric brain tumor biology and inform rational treatment selection.

Depletion of autoreactive plasma cells and treatment of lupus nephritis in mice using CEP-33779, a novel, orally active, selective inhibitor of JAK2.

Accumulating evidence suggests that autoreactive plasma cells play an important role in systemic lupus erythematosus (SLE). In addition, several proinflammatory cytokines promote autoreactive B cell maturation and autoantibody production. Hence, therapeutic targeting of such cytokine pathways using a selective JAK2 inhibitor, CEP-33779 (JAK2 enzyme IC(50) = 1.3 nM; JAK3 enzyme IC(50)/JAK2 enzyme IC(50) = 65-fold), was tested in two mouse models of SLE. Age-matched, MRL/lpr or BWF1 mice with established SLE or lupus nephritis, respectively, were treated orally with CEP-33779 at 30 mg/kg (MRL/lpr), 55 mg/kg or 100 mg/kg (MRL/lpr and BWF1). Studies included reference standard, dexamethasone (1.5 mg/kg; MRL/lpr), and cyclophosphamide (50 mg/kg; MRL/lpr and BWF1). Treatment with CEP-33779 extended survival and reduced splenomegaly/lymphomegaly. Several serum cytokines were significantly decreased upon treatment including IL-12, IL-17A, IFN-α, IL-1ß, and TNF-α. Anti-nuclear Abs and frequencies of autoantigen-specific, Ab-secreting cells declined upon CEP-33779 treatment. Increased serum complement levels were associated with reduced renal JAK2 activity, histopathology, and spleen CD138(+) plasma cells. The selective JAK2 inhibitor CEP-33779 was able to mitigate several immune parameters associated with SLE advancement, including the protection and treatment of mice with lupus nephritis. These data support the possibility of using potent, orally active, small-molecule inhibitors of JAK2 to treat the debilitative disease SLE.

A multi-institutional pediatric dataset of clinical radiology MRIs by the Children's Brain Tumor Network.

Pediatric brain and spinal cancers remain the leading cause of cancer-related death in children. Advancements in clinical decision-support in pediatric neuro-oncology utilizing the wealth of radiology imaging data collected through standard care, however, has significantly lagged other domains. Such data is ripe for use with predictive analytics such as artificial intelligence (AI) methods, which require large datasets. To address this unmet need, we provide a multi-institutional, large-scale pediatric dataset of 23,101 multi-parametric MRI exams acquired through routine care for 1,526 brain tumor patients, as part of the Children's Brain Tumor Network. This includes longitudinal MRIs across various cancer diagnoses, with associated patient-level clinical information, digital pathology slides, as well as tissue genotype and omics data. To facilitate downstream analysis, treatment-naïve images for 370 subjects were processed and released through the NCI Childhood Cancer Data Initiative via the Cancer Data Service. Through ongoing efforts to continuously build these imaging repositories, our aim is to accelerate discovery and translational AI models with real-world data, to ultimately empower precision medicine for children.

The children's brain tumor network (CBTN) - Accelerating research in pediatric central nervous system tumors through collaboration and open science.

Pediatric brain tumors are the leading cause of cancer-related death in children in the United States and contribute a disproportionate number of potential years of life lost compared to adult cancers. Moreover, survivors frequently suffer long-term side effects, including secondary cancers. The Children's Brain Tumor Network (CBTN) is a multi-institutional international clinical research consortium created to advance therapeutic development through the collection and rapid distribution of biospecimens and data via open-science research platforms for real-time access and use by the global research community. The CBTN's 32 member institutions utilize a shared regulatory governance architecture at the Children's Hospital of Philadelphia to accelerate and maximize the use of biospecimens and data. As of August 2022, CBTN has enrolled over 4700 subjects, over 1500 parents, and collected over 65,000 biospecimen aliquots for research. Additionally, over 80 preclinical models have been developed from collected tumors. Multi-omic data for over 1000 tumors and germline material are currently available with data generation for > 5000 samples underway. To our knowledge, CBTN provides the largest open-access pediatric brain tumor multi-omic dataset annotated with longitudinal clinical and outcome data, imaging, associated biospecimens, child-parent genomic pedigrees, and in vivo and in vitro preclinical models. Empowered by NIH-supported platforms such as the Kids First Data Resource and the Childhood Cancer Data Initiative, the CBTN continues to expand the resources needed for scientists to accelerate translational impact for improved outcomes and quality of life for children with brain and spinal cord tumors.

Optimization of a novel kinase inhibitor scaffold for the dual inhibition of JAK2 and FAK kinases.

The elaboration of a novel scaffold for the inhibition of JAK2 and FAK kinases was targeted in order to provide a dual inhibitor that could target divergent pathways for tumor cell progression.

2,7-Pyrrolo[2,1-f][1,2,4]triazines as JAK2 inhibitors: modification of target structure to minimize reactive metabolite formation.

The JAK2/STAT pathway has important roles in hematopoiesis. With the discovery of the JAK2 V617F mutation and its presence in many patients with myeloproliferative neoplasms, research in the JAK2 inhibitor arena has dramatically increased. We report a novel series of potent JAK2 inhibitors containing a 2,7-pyrrolotriazine core. To minimize potential drug-induced toxicity, targets were analyzed for the ability to form a glutathione adduct. Glutathione adduct formation was decreased by modification of the aniline substituent at C2.

A Cellular Assay for Inhibitors of the Fatty Acid Biosynthetic Pathway Using Scintillating Microplates.

A simplified method for monitoring the incorporation of radiolabeled acetate into lipids in a cellular system is described. The assay eliminates the commonly employed labor-intensive organic extraction step by plating the cells in 96-well tissue culture-treated ScintiPlates(®) that enable direct measurement of radiolabeled cell membrane-embedded lipids. Since the scintillant is entrenched in the plates, radioactivity in close proximity to the scintillant is measured without the need for liquid scintillation cocktail. The utility of this method for evaluating inhibitors of the de novo fatty acid synthetic pathway is demonstrated here with fatty acid synthase (FASN). Due to the upregulation of FASN activity in many tumor types, development of inhibitors to block the FASN activity in cells shows promise as an attractive and tractable approach for therapeutic intervention.

Comparison of LanthaScreen Eu kinase binding assay and surface plasmon resonance method in elucidating the binding kinetics of focal adhesion kinase inhibitors.

An understanding of the dynamics of drug-target interactions is important in the drug discovery process. Information related to the binding kinetics of a drug toward its target or off-target aids in determining the efficacy or toxicity of a drug. Biophysical techniques such as surface plasmon resonance (SPR) have been available for over 20 years, but have been predominantly utilized to characterize protein-protein interactions. With improvements in instrument sensitivity and data analysis software, interactions between proteins (such as kinases) and small molecules have been successfully evaluated. More recently, the LanthaScreen Eu kinase binding assay for characterizing kinase inhibitors has been described. This assay monitors displacement of an Alexa Fluor 647-labeled tracer from the ATP-binding site of an epitope-tagged kinase by a test compound. Such behavior results in a decrease in time-resolved fluorescence energy transfer signal. In this report, a side-by-side comparison of the LanthaScreen Eu kinase binding assay and the SPR method was performed using inhibitors of focal adhesion kinase. The two methods yielded comparable results and identified compounds with time-dependent inhibition and relatively slow dissociation.

Comparison of two homogeneous cell-based kinase assays for JAK2 V617F: SureFire pSTAT5 and GeneBLAzer fluorescence resonance energy transfer assays.

The Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway plays an important role in cellular responses to cytokines and growth factors. Recent studies have identified a recurrent somatic activating mutation (JAK2 V617F) in majority of patients with myeloproliferative disorders (MPDs). Development of drugs that target JAK2 V617F is, therefore, of therapeutic relevance. To discover small molecule inhibitors for this target, robust and reliable cell-based assays are important. Here, we present a comparison of two homogeneous, 384-well plate-based cellular assays using Invitrogen's CellSensor® JAK2 V617F interferon regulatory factor-1 (irf1)-beta-lactamase (bla) human erythroleukemia line (HEL): (1) SureFire® pSTAT5 AlphaScreen® assay from PerkinElmer; and (2) GeneBLAzer® fluorescence resonance energy transfer assay from Invitrogen. HEL cells are growth factor-independent due to JAK2 V617F mutation that causes constitutive STAT5 activation. The SureFire assay measures levels of phosphorylated STAT5 downstream of JAKs, while the GeneBLAzer assay is a reporter assay that monitors bla activity further downstream of STAT5. Evaluation of a number of chemically diverse JAK2 inhibitors in the two cellular assays yielded comparable half-maximal inhibitory concentration (IC50) values, boding well for the utility of these assay formats in compound profiling.

Time-resolved fluorescence resonance energy transfer as a versatile tool in the development of homogeneous cellular kinase assays.

Homogeneous cellular assays can streamline product detection in the drug discovery process. One commercially available assay employing time-resolved fluorescence resonance energy transfer (TR-FRET) that detects phosphorylated products was used to evaluate inhibitors of the receptor tyrosine kinase AXL in a cell line expressing an AXL-green fluorescent protein fusion protein. This TR-FRET assay was modified to evaluate the phosphorylation state of the AXL family member MER in a cell line expressing MER with a V5 tag by adding a fluorescein-labeled anti-V5 antibody. This homogeneous cellular assay was further modified to evaluate the nonreceptor tyrosine kinase focal adhesion kinase (FAK) in cell lines that expressed an untagged kinase by the inclusion of a commercially available anti-FAK antibody conjugated with an acceptor dye. The methods described here can be further adapted for TR-FRET detection of other cellular kinase activities.

A selective, orally bioavailable 1,2,4-triazolo[1,5-a]pyridine-based inhibitor of Janus kinase 2 for use in anticancer therapy: discovery of CEP-33779.

Members of the JAK family of nonreceptor tyrosine kinases play a critical role in the growth and progression of many cancers and in inflammatory diseases. JAK2 has emerged as a leading therapeutic target for oncology, providing a rationale for the development of a selective JAK2 inhibitor. A program to optimize selective JAK2 inhibitors to combat cancer while reducing the risk of immune suppression associated with JAK3 inhibition was undertaken. The structure-activity relationships and biological evaluation of a novel series of compounds based on a 1,2,4-triazolo[1,5-a]pyridine scaffold are reported. Para substitution on the aryl at the C8 position of the core was optimum for JAK2 potency (17). Substitution at the C2 nitrogen position was required for cell potency (21). Interestingly, meta substitution of C2-NH-aryl moiety provided exceptional selectivity for JAK2 over JAK3 (23). These efforts led to the discovery of CEP-33779 (29), a novel, selective, and orally bioavailable inhibitor of JAK2.

Modification of CellSensor irf1-bla TF-1 and irf1-bla HEL assays for direct comparison of wild-type JAK2 and JAK2 V617F inhibition.

The Janus kinase (JAK)-signal transducer and activator of transcription pathway is an important therapeutic target because of its role in the regulation of cell growth. Aberrant, constitutive activation of JAK2 signaling has been implicated in myeloproliferative disorders with a single, activating somatic V617F mutation in the JH2 pseudokinase domain of JAK2 as the prevalent molecular lesion. Invitrogen has developed the CellSensor(®) cell lines interferon regulatory factor-1 (irf1)-beta-lactamase (bla) TF-1 and irf1-bla HEL for use in evaluating inhibitors of wild-type JAK2 and mutant JAK2 V617F, respectively. Both contain a bla reporter gene downstream of the irf1 response element stably integrated into either TF-1 or HEL cells. A fluorescence resonance energy transfer-based bla substrate is utilized to give a robust detection of JAK2 activity. Examination of Invitrogen's protocols for the two cell lines revealed significant differences that are not conducive to direct comparison of inhibitor activities against wild-type and mutant JAK2. Systematic changes to standardize the two assays were incorporated and evaluated for effects on assay response ratio, assay quality, and potency for a diverse series of inhibitors.

Lymphatic malformations of the tongue base.

PURPOSE: In light of the paucity of literature on lymphatic malformations of the tongue base, our aim was to present our experience and long-term outcomes of patients with this rare and challenging pathologic entity. METHODS: Medical records of 25 patients treated by the 3 senior authors (RGA, MTC, and RTC) between 1974 and 2003 were retrospectively reviewed, and comprehensive clinical data were collected and analyzed. RESULTS: Twenty-one patients (13 female and 12 male infants) were diagnosed either prenatally or at birth. Of these patients, 18 required early airway stabilization; 17 required tracheotomy. Four patients were diagnosed after 1 year of age and had no airway problems. Follow-up ranged from 2 days (owing to death) to 28 years, with a mean of 10 years. In 21 patients, pathology was extensive, involving contiguous anatomical areas such as the anterior tongue, larynx, pharynx, and floor of mouth. Multiple resections and debulking procedures were performed to restore function and improve cosmesis. Four patients died, all with laryngeal involvement. Of the 14 survivors who had tracheotomies, only 5 are decannulated. Normal oral feeding has been achieved in 14 patients and normal speech, in 8 patients. Cosmesis has improved with time. Orthodontic and dental problems are common, and 9 patients have significant macrognathia. CONCLUSIONS: Although most patients with lymphatic malformations of the tongue base achieve normal oral feeding, airway, speech, and cosmesis issues remain problematic throughout life. Laryngeal involvement signifies extensive disease and is the most significant risk factor for serious complications and death.