Publications by authors named "Shannon He"

Pleomorphic xanthoastrocytoma (PXA) is a rare subset of primary pediatric glioma with 70% 5-year disease free survival. However, up to 20% of cases present with local recurrence and malignant transformation into more aggressive type anaplastic PXA (AXPA) or glioblastoma. The understanding of disease etiology and mechanisms driving PXA and APXA are limited, and there is no standard of care.

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Establishment of clinically annotated, molecularly characterized, patient-derived xenografts (PDXs) from treatment-naïve and pretreated patients provides a platform to test precision genomics-guided therapies. An integrated multi-OMICS pipeline was developed to identify cancer-associated pathways and evaluate stability of molecular signatures in a panel of pediatric and AYA PDXs following serial passaging in mice. Original solid tumor samples and their corresponding PDXs were evaluated by whole-genome sequencing, RNA-seq, immunoblotting, pathway enrichment analyses, and the drug−gene interaction database to identify as well as cross-validate actionable targets in patients with sarcomas or Wilms tumors.

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Chronic cerebral hypoperfusion (CCH) may amplify the neurotoxicity of nanoscale particulate matter (nPM), resulting in white matter injury. This study characterized the joint effects of nPM (diameter ≤ 200 nm) and CCH secondary to bilateral carotid artery stenosis (BCAS) exposure on neuronal and white matter injury in a murine model. nPM was collected near a highway and re-aerosolized for exposure.

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Despite improved therapeutic and clinical outcomes for patients with localized diseases, outcomes for pediatric and AYA sarcoma patients with high-grade or aggressive disease are still relatively poor. With advancements in next generation sequencing (NGS), precision medicine now provides a strategy to improve outcomes in patients with aggressive disease by identifying biomarkers of therapeutic sensitivity or resistance. The integration of NGS into clinical decision making not only increases the accuracy of diagnosis and prognosis, but also has the potential to identify effective and less toxic therapies for pediatric and AYA sarcomas.

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Purpose: Glioblastoma (GBM) is a malignant brain tumor with a poor long-term prognosis due to recurrence from highly resistant GBM cancer stem cells (CSCs), for which the current standard of treatment with temozolomide (TMZ) alone will unlikely produce a viable cure. In addition, CSCs regenerate rapidly and overexpress methyl transferase which overrides the DNA-alkylating mechanism of TMZ, leading to resistance. The objective of this research was to apply the concepts of nanotechnology to develop a multi-drug therapy, TMZ and idasanutlin (RG7388, a potent mouse double minute 2 (MDM2) antagonist), loaded in functionalized nanoparticles (NPs) that target the GBM CSC subpopulation, reduce the cell viability and provide possibility of in vivo preclinical imaging.

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Study Objectives: Sleep deprivation induces systemic inflammation that may contribute to stress vulnerability and other pathologies. We tested the hypothesis that immunization with heat-killed Mycobacterium vaccae NCTC 11659 (MV), an environmental bacterium with immunoregulatory and anti-inflammatory properties, prevents the negative impacts of 5 days of sleep disruption on stress-induced changes in sleep, behavior, and physiology in mice.

Methods: In a 2 × 2 × 2 experimental design, male C57BL/6N mice were given injections of either MV or vehicle on days -17, -10, and -3.

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Osteosarcoma (OS) patients exhibit poor overall survival, partly due to copy number variations (CNVs) resulting in dysregulated gene expression and therapeutic resistance. To identify actionable prognostic signatures of poor overall survival, we employed a systems biology approach using public databases to integrate CNVs, gene expression, and survival outcomes in pediatric, adolescent, and young adult OS patients. Chromosome 8 was a hotspot for poor prognostic signatures.

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Purpose: To explore postanesthesia care unit (PACU) nurses' interactions with technology during the critical Phase I recovery period.

Design: Interpretive description was used to understand nurses' experiences.

Methods: Nine PACU nurses were recruited from three mid-sized hospitals within the same health authority in a Western Canadian province.

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It has been established in recent years that the gut microbiome plays a role in health and disease, potentially via alterations in metabolites that influence host physiology. Although sleep disruption and gut dysbiosis have been associated with many of the same diseases, studies investigating the gut microbiome in the context of sleep disruption have yielded inconsistent results, and have not assessed the fecal metabolome. We exposed mice to five days of sleep disruption followed by four days of ad libitum recovery sleep, and assessed the fecal microbiome and fecal metabolome at multiple timepoints using 16S rRNA gene amplicons and untargeted LC-MS/MS mass spectrometry.

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The Hippo pathway coordinates extracellular signals onto the control of tissue homeostasis and organ size. Hippo signaling primarily regulates the ability of Yap1 to bind and co-activate TEA domain (TEAD) transcription factors. Yap1 tightly binds to TEAD4 via a large flat interface, making the development of small-molecule orthosteric inhibitors highly challenging.

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OBJECTIVE Improvement in treatment outcome for patients with glioblastoma multiforme (GBM) requires a multifaceted approach due to dysregulation of numerous signaling pathways. The murine double minute 2 (MDM2) protein may fulfill this requirement because it is involved in the regulation of growth, survival, and invasion. The objective of this study was to investigate the impact of modulating MDM2 function in combination with front-line temozolomide (TMZ) therapy in GBM.

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Triple-negative breast cancers (TNBC) are typically resistant to treatment, and strategies that build upon frontline therapy are needed. Targeting the murine double minute 2 (Mdm2) protein is an attractive approach, as Mdm2 levels are elevated in many therapy-refractive breast cancers. The Mdm2 protein-protein interaction inhibitor Nutlin-3a blocks the binding of Mdm2 to key signaling molecules such as p53 and p73α and can result in activation of cell death signaling pathways.

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Effective treatments for primary brain tumors and brain metastases represent a major unmet medical need. Targeting the CDK4/CDK6-cyclin D1-Rb-p16/ink4a pathway using a potent CDK4 and CDK6 kinase inhibitor has potential for treating primary central nervous system tumors such as glioblastoma and some peripheral tumors with high incidence of brain metastases. We compared central nervous system exposures of two orally bioavailable CDK4 and CDK6 inhibitors: abemaciclib, which is currently in advanced clinical development, and palbociclib (IBRANCE; Pfizer), which was recently approved by the U.

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Objectives: The purpose of the present study was to develop and validate noninvasive bioluminescence imaging methods for differentially monitoring primary and abdominal metastatic tumor growth in mouse orthotopic models of pancreatic cancer.

Methods: A semiautomated maximum entropy segmentation method was implemented for the primary tumor region of interest, and a rule-based method for manually drawing a region of interest for the abdominal metastatic region was developed for monitoring tumor growth in orthotopic models of pancreatic cancer. The 2 region-of-interest methods were validated by having 2 observers independently segment Panc-1 tumors, and the results were compared with the number of mesenteric lymph node nodules and histopathologic assessment of liver metastases.

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Using an innovative approach toward multiple carbon-carbon bond-formations that relies on the multifaceted catalytic properties of titanocene complexes we constructed a series of C1-C7 analogs of curcumin for evaluation as brain and peripheral nervous system anti-cancer agents. C2-Arylated analogs proved efficacious against neuroblastoma (SK-N-SH & SK-N-FI) and glioblastoma multiforme (U87MG) cell lines. Similar inhibitory activity was also evident in p53 knockdown U87MG GBM cells.

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We have explored the decahydroisoquinoline scaffold, bearing a phenyl tetrazole, as GluK1 antagonists with potential as oral analgesics. We have established the optimal linker atom between decahydroisoquinoline and phenyl rings and demonstrated an improvement of both the affinity for the GluK1 receptor and the selectivity against the related GluA2 receptor with proper phenyl substitution. In this Letter, we also disclose in vivo data that led to the discovery of LY545694·HCl, a compound with oral efficacy in two persistent pain models.

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The synthesis and structure-activity relationship of decahydroisoquinoline derivatives with various benzoic acid substitutions as GluK1 antagonists are described. Potent and selective antagonists were selected for a tailored prodrug approach in order to facilitate the evaluation of the new compounds in pain models after oral administration. Several diester prodrugs allowed for acceptable amino acid exposure and moderate efficacy in vivo.

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Pancreatic cancer often presents in advanced stages and is unresponsive to conventional treatments. Thus, the need to develop novel treatment strategies for pancreatic cancer has never been greater. Here, we report that combination of focal irradiation with hedgehog (Hh) signaling inhibition exerts better than additive effects on reducing metastases.

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Purpose: To evaluate the reproducibility of the measurement of the total choline-to-water ratio, and the effect of repositioning the subject between scans, using (1) H-magnetic resonance spectroscopy in a mouse U87MG xenograft model.

Materials And Methods: In vivo single-voxel MR spectra at 7T from xenograft tumors were obtained using both a water-suppressed and a nonwater-suppressed point-resolved spectroscopy (PRESS) sequence. Reproducibility of the total choline/water ratio was evaluated under the conditions of immediate rescan with no change in position of the animal or voxel, immediate reposition, and reposition after 1 or 7 days.

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The anticonvulsant ameltolide (LY201116) is a novel potential therapy for the treatment of canine epilepsy. Eight dogs were administered five different oral doses of ameltolide and clinical scoring of the maximal electroshock (MES) induced seizures at 3 and 24 h postdosing were determined in two separate crossover design studies. Plasma ameltolide concentrations were determined at the time of seizures in all dogs and complete plasma concentration-time profiles were also determined in a separate study.

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Selective inhibitors of the glycine transporter 1 (GlyT1) have been implicated in central nervous system disorders related to hypoglutamatergic function such as schizophrenia. The selective GlyT1 inhibitors ALX5407 (NFPS) and LY2365109 {[2-(4-benzo[1,3]dioxol-5-yl-2-tert-butylphenoxy)ethyl]-methylamino}-acetic acid increased cerebrospinal fluid levels of glycine and potentiated NMDA-induced increases in dialysate levels of neurotransmitters in the prefrontal cortex (PFC) and the striatum. However, higher doses produced both stimulatory and inhibitory effects on motor performance and impaired respiration, suggesting significant involvement of cerebellar and brain stem areas.

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The development and validation of the maximal electro-shock (MES) model using phenobarbital (Pb) as the positive control is described. This approach builds on previous work in rodent model systems, and has been adapted to dogs as a tool for pharmaceutical dose selection. Dogs, like rodents, exhibit generalized convulsions which manifest as progressive clinical signs in a dose (electrical current) dependent fashion.

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In humans, kappa opioid receptor agonists produce, among other effects, sedation and difficulty concentrating, suggesting that they may disrupt attention. The purpose of the present studies was therefore to evaluate the effects of kappa opioid receptor agonists on attention as assessed by a 5-choice serial reaction time task in rats. The kappa opioid receptor agonists (+)-U69,593 (0.

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The localization of serotonin-7 (5-HT(7)) receptors and the biological activity of ligands have suggested that 5-HT(7) receptors might be involved in pain, migraine, epilepsy, anxiety, depression, memory, and sleep. In the present study, the potential involvement of 5-HT(7) receptors in epilepsy and other seizure disorders was assessed by comparing the seizures produced by three types of electrical stimulation and three chemical convulsants in 5-HT(7) receptor-deficient (knockout, KO) mice to those seizures observed in wild-type (WT) mice. Thresholds for producing electroshock-induced clonic seizures did not differ between KO versus WT mice.

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Working memory is a theoretical concept referring to a set of cognitive processes that provide temporary maintenance and manipulation of the information necessary for complex cognitive tasks. The preponderance of working memory tasks emphasizes the maintenance of information, and, is spatially oriented. Working memory tasks which are not spatially oriented and which require not only the maintenance but also the manipulation of information are needed in order to further our understanding of working memory in animals.

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