35 research outputs found
Integrated self-healing thermal protection for high-speed vehicles
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EHD2 Promotes Store-Operated Calcium Entry (SOCE) and Cellular Migration in Ovarian Cancer Cells
Ovarian cancer (OC) ranks as the 5th most common cause of cancer deaths of women, reflecting late diagnoses and lack of targeted therapies. EHD2, a member of the Eps15 homology (EH) domain containing (EHD) proteins family, regulates cell surface expression of Orai1, the mediator of store-operated calcium entry (SOCE) in breast cancer. Disrupting the EHD2-Orai1 axis in OC could provide novel targeted therapies against metastatic disease.https://digitalcommons.unmc.edu/surp2023/1002/thumbnail.jp
Comparative Immunohistochemical Analysis of EHD1 Expression in Adjacent, Metastatic, and Normal Thyroid Tissue
The discovery of prognostic biomarkers plays a crucial role in enhancing the treatment and care of individuals with differentiated thyroid cancer (DTC) who are at risk of disease progression. A significant breakthrough came with earlier research, which revealed higher levels of the EHD1 protein in papillary DTC when compared to the surrounding healthy tissue. This exciting finding served as the driving force behind the initiation of a more extensive investigation aimed at validating EHD1 as a potential biomarker and exploring its connection with clinical outcomes. By unraveling the potential implications of EHD1 in DTC cases, this study holds the promise of advancing our understanding and approach to managing this type of cancer effectively.https://digitalcommons.unmc.edu/surp2023/1001/thumbnail.jp
Loss of Cbl and Cbl-b ubiquitin ligases abrogates hematopoietic stem cell quiescence and sensitizes leukemic disease to chemotherapy.
Cbl and Cbl-b are tyrosine kinase-directed RING finger type ubiquitin ligases (E3s) that negatively regulate cellular activation pathways. E3 activity-disrupting human Cbl mutations are associated with myeloproliferative disorders (MPD) that are reproduced in mice with Cbl RING finger mutant knock-in or hematopoietic Cbl and Cbl-b double knockout. However, the role of Cbl proteins in hematopoietic stem cell (HSC) homeostasis, especially in the context of MPD is unclear. Here we demonstrate that HSC expansion and MPD development upon combined Cbl and Cbl-b deletion are dependent on HSCs. Cell cycle analysis demonstrated that DKO HSCs exhibit reduced quiescence associated with compromised reconstitution ability and propensity to undergo exhaustion. We show that sustained c-Kit and FLT3 signaling in DKO HSCs promotes loss of colony-forming potential, and c-Kit or FLT3 inhibition in vitro protects HSCs from exhaustion. In vivo, treatment with 5-fluorouracil hastens DKO HSC exhaustion and protects mice from death due to MPD. Our data reveal a novel and leukemia therapy-relevant role of Cbl and Cbl-b in the maintenance of HSC quiescence and protection against exhaustion, through negative regulation of tyrosine kinase-coupled receptor signaling
EHD1 is Required for IGF-1R-mediated Oncogenic Signaling in Ewing Sarcoma
Background and Significance: Ewing Sarcoma (EWS) is the second most common malignant bone tumor of children and adolescents. Patients with metastatic or recurrent disease have very poor outcomes. The receptor tyrosine kinase(RTK) insulin-like-growth-factor-1-receptor (IGF-1R) is upregulated in 93% of EWS patients with anti-IGF-1R antibodies and kinase inhibitors in clinical studies. However, with only ~10% of patients achieving objective responses, delineation of novel pathways that facilitate IGF-1R-driven oncogenesis in EWS could provide avenues for more effective therapy. The RTK levels and compartmentalization at the cell surface determine their access to growth factors, thus dictating the downstream oncogenic signaling. Our lab has demonstrated that EPS15-homology-domain-containing-protein-1 (EHD1) regulates traffic of cell surface receptors, including RTKs. We observed high frequency (67%) of EHD1 overexpression in 266 primary EWS patient tumor tissues, and Kaplan-Meier survival analysis of publicly available mRNA expression data showed that high EHD1 expression was associated with shorter patient survival.
Objective/Question: This study aims to comprehend the underlying role of EHD1 in EWS oncogenesis.
Experimental design and Results: In both dox-inducible EHD1-shRNA knockdown and EHD1-CRISPR-Cas9-knockout (KO) EWS cell line models(TC71, A673, and SKES1), we observed a significant impairment of in vitro oncogenic properties namely, cell proliferation, migration, invasion, soft-agar colony formation, and tumor-sphere formation, and the phenotypes were restored upon mouse-EHD1 rescue. Furthermore, by orthotopically implanting TC71 cells in the tibia of nude mice(xenograft model), we demonstrated a significant reduction in tumor size upon EHD1-depletion. Using a phospho-RTK profiling antibody array, we found reduced phospho-IGF-1R levels upon EHD1-KD, identifying IGF-1R as a potential target of regulation by EHD1. EHD1-KO reduced surface IGF-1R levels under steady-state and ligand-free conditions in EWS cells. IGF-1R and EHD1 were also found to colocalize intracellularly and co-immunoprecipitate after IGF-1 stimulation. Notably, EHD1-KO impaired the IGF-1R-mediated activation of downstream AKT and MAPK pathways. Mechanistically, EHD1 was shown to regulate traffic of newly synthesized IGF-1R and recycled pools from the Golgi to the cell surface, and in absence of EHD1, intracellular IGF-1R was shunted to the lysosome resulting in degradation. Finally, by dual targeting of EHD1 (genetic depletion) and IGF-1R (small-molecule-inhibitor Linsitinib), we observed an additive effect on inhibition of EWS cell proliferation and migration and upregulation of apoptosis.
Conclusions: Our studies indicate a novel regulatory pathway of EHD1 requirement in IGF-1R cell surface display and sustaining IGF-1R-mediated oncogenesis in EWS. This highlights the prospects of therapeutic co-targeting of EHD1 and IGF-1R, thus enhancing IGF-1R targeted therapies in EWS.https://digitalcommons.unmc.edu/chri_forum/1040/thumbnail.jp
Mechanistically-guided materials chemistry: synthesis of new ternary nitrides, CaZrN and CaHfN
Recent computational studies have predicted many new ternary nitrides,
revealing synthetic opportunities in this underexplored phase space. However,
synthesizing new ternary nitrides is difficult, in part because intermediate
and product phases often have high cohesive energies that inhibit diffusion.
Here, we report the synthesis of two new phases, calcium zirconium nitride
(CaZrN) and calcium hafnium nitride (CaHfN), by solid state metathesis
reactions between CaN and Cl ( = Zr, Hf). Although the
reaction nominally proceeds to the target phases in a 1:1 ratio of the
precursors via CaN + Cl CaN + 2 CaCl,
reactions prepared this way result in Ca-poor materials (CaN,
). A small excess of CaN (ca. 20 mol\%) is needed to yield
stoichiometric CaN, as confirmed by high-resolution synchrotron powder
X-ray diffraction. In situ synchrotron X-ray diffraction studies reveal that
nominally stoichiometric reactions produce Zr intermediates early in the
reaction pathway, and the excess CaN is needed to reoxidize Zr
intermediates back to the Zr oxidation state of CaZrN. Analysis of
computationally-derived chemical potential diagrams rationalizes this synthetic
approach and its contrast from the synthesis of MgZrN. These findings
additionally highlight the utility of in situ diffraction studies and
computational thermochemistry to provide mechanistic guidance for synthesis
Ways of Asking, Ways of Telling: A Methodological Comparison of Ethnographic and Research Diagnostic Interviews
The interpretive understanding that can be derived from interviews is highly influenced by methods of data collection, be they structured or semistructured, ethnographic, clinical, life-history or survey interviews. This article responds to calls for research into the interview process by analyzing data produced by two distinctly different types of interview, a semistructured ethnographic interview and the Structured Clinical Interview for DSM, conducted with participants in the Navajo Healing Project. We examine how the two interview genres shape the context of researcher-respondent interaction and, in turn, influence how patients articulate their lives and their experience in terms of illness, causality, social environment, temporality and self/identity. We discuss the manner in which the two interviews impose narrative constraints on interviewers and respondents, with significant implications for understanding the jointly constructed nature of the interview process. The argument demonstrates both divergence and complementarity in the construction of knowledge by means of these interviewing methods
Ecdysoneless Overexpression Drives Mammary Tumorigenesis through Upregulation of C-MYC and Glucose Metabolism
Ecdysoneless (ECD) protein is essential for embryogenesis, cell-cycle progression, and cellular stress mitigation with an emerging role in mRNA biogenesis. We have previously shown that ECD protein as well as its mRNA are overexpressed in breast cancer and ECD overexpression predicts shorter survival in patients with breast cancer. However, the genetic evidence for an oncogenic role of ECD has not been established. Here, we generated transgenic mice with mammary epithelium-targeted overexpression of an inducible human ECD transgene (ECDTg). Significantly, ECDTg mice develop mammary hyperplasia, preneoplastic lesions, and heterogeneous tumors with occasional lung metastasis. ECDTg tumors exhibit epithelial to mesenchymal transition and cancer stem cell characteristics. Organoid cultures of ECDTg tumors showed ECD dependency for in vitro oncogenic phenotype and in vivo growth when implanted in mice. RNA sequencing (RNA-seq) analysis of ECDTg tumors showed a c-MYC signature, and alterations in ECD levels regulated c-MYC mRNA and protein levels as well as glucose metabolism. ECD knockdown-induced decrease in glucose uptake was rescued by overexpression of mouse ECD as well as c-MYC. Publicly available expression data analyses showed a significant correlation of ECD and c-MYC overexpression in breast cancer, and ECD and c-MYC coexpression exhibits worse survival in patients with breast cancer. Taken together, we establish a novel role of overexpressed ECD as an oncogenesis driver in the mouse mammary gland through upregulation of c-MYC-mediated glucose metabolism.
IMPLICATIONS: We demonstrate ECD overexpression in the mammary gland of mice led to the development of a tumor progression model through upregulation of c-MYC signaling and glucose metabolism
Developing the Enquiring Student and Enhancing the Research-Teaching Interface: Student-led Pedagogical Research and Educational Initiatives in Enquiry Based Learning
This paper describes the progress of a project running at the University of Glasgow to develop elements of Enquiry Based Learning (EBL) in undergraduate degree courses across a range of disciplines. It focuses on the second part of the project but an overview of the first part is also given. During phase 1 of the project, in the summer of 2007, seven undergraduate students spent four weeks working together exploring enquiry based learning (EBL) in the institutionâs central, educational development unit. This phase was approached as an EBL exercise itself; the student groups were given full responsibility for the process with the proviso that by the end of this phase they would have developed a guide for staff and students about EBL. The second phase of the project continues throughout the academic year 07/08. Here, each student worked alongside a member of staff from their department of study to develop discipline specific EBL activities taking a research-informed approach to this development. All pairings were charged with introducing EBL such that no major course change procedures had to be followed; this hopefully ensured the sustainability of such adjustments. Staff and students involved in the project represent dentistry, chemistry, biology, theology, law and psychology and the courses under development range from large first year classes to small honours level courses. An overview of the range of enquiry-based learning developments within the courses will be described
Developing the Enquiring Student and Enhancing the Research-Teaching Interface: Student-led Pedagogical Research and Educational Initiatives in Enquiry Based Learning
This paper describes the progress of a project running at the University of Glasgow to develop elements of Enquiry Based Learning (EBL) in undergraduate degree courses across a range of disciplines. It focuses on the second part of the project but an overview of the first part is also given. During phase 1 of the project, in the summer of 2007, seven undergraduate students spent four weeks working together exploring enquiry based learning (EBL) in the institutionâs central, educational development unit. This phase was approached as an EBL exercise itself; the student groups were given full responsibility for the process with the proviso that by the end of this phase they would have developed a guide for staff and students about EBL. The second phase of the project continues throughout the academic year 07/08. Here, each student worked alongside a member of staff from their department of study to develop discipline specific EBL activities taking a research-informed approach to this development. All pairings were charged with introducing EBL such that no major course change procedures had to be followed; this hopefully ensured the sustainability of such adjustments. Staff and students involved in the project represent dentistry, chemistry, biology, theology, law and psychology and the courses under development range from large first year classes to small honours level courses. An overview of the range of enquiry-based learning developments within the courses will be described