scholarly journals DIPG-51. ACVR1 MUTATIONS PROMOTE TUMOR GROWTH IN MODELS OF DIFFUSE INTRINSIC PONTINE GLIOMA

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii296-iii297
Author(s):  
Jennifer Ocasio Adorno ◽  
Laura Hover ◽  
Chen He ◽  
Xiaoyan Zhu ◽  
David Goldhamer ◽  
...  
Keyword(s):  
Tumor Growth ◽  
Cell Fate ◽  
High Grade Glioma ◽  
Diffuse Intrinsic Pontine Glioma ◽  
Genetically Engineered ◽  
Gene Encoding ◽  
Human Patient ◽  
Complete Penetrance ◽  
Genetically Engineered Mice ◽  
Glial Progenitors

Abstract Mutations in the gene encoding activin A receptor type 1 (ACVR1) are found in approximately 25% of diffuse intrinsic pontine gliomas (DIPGs), a pediatric glioma with 2-year survival rate of less than 10%. ACVR1mutations frequently coincide with activating PIK3CA or PIK3R1 mutations, indicating a potential cooperative effect of BMP and PI3K signaling in gliomagenesis. We used genetically engineered mice with inducible knock-in of Acvr1R206H or Pik3caE545K alleles, such that cre-mediated recombination resulted in expression of the gain of function mutated genes from their endogenous promoters at physiological levels. Cre-mediated deletion in GFAP-CreER;Pik3caE545K/+;p53cKO mice (Pik3ca;p53) mediated Trp53 deletion and expression of Pik3caE545K in glial progenitors, and spontaneously induced high-grade glioma (HGG) in mice with complete penetrance. Heterozygous knock-in of the Acvr1R206H allele accelerated tumorigenesis and impaired survival in Pik3ca;p53 mice (Acvr1;Pik3ca;p53). Transcriptomic analysis of Acvr1;Pik3ca;p53 tumors compared to Pik3ca;p53 littermate controls, as in patient-derived tumors, revealed broad molecular signatures associated with cell fate commitment and chromosome maintenance. Pharmacologic inhibition of ACVR1 was sufficient to impair growth in human patient-derived DIPG cell lines. Together, our studies show that ACVR1 activation promotes tumor growth in spontaneous mouse HGG and patient-derived DIPG cells, suggesting that ACVR1 inhibition may produce a clinically significant therapeutic effect in DIPG.

scholarly journals TGF-β Signaling and the Epithelial-Mesenchymal Transition during Palatal Fusion

2018 ◽  
Vol 19 (11) ◽  
pp. 3638 ◽  
Author(s):  
Akira Nakajima ◽  
Charles F. Shuler ◽  
Alexander Gulka ◽  
Jun-ichi Hanai
Keyword(s):  
Cell Fate ◽  
Transforming Growth Factor ◽  
Epithelial Mesenchymal Transition ◽  
Genetically Engineered ◽  
Fusion Process ◽  
Mesenchymal Transition ◽  
Morphological Process ◽  
Palatal Fusion ◽  
Genetically Engineered Mice

Signaling by transforming growth factor (TGF)-β plays an important role in development, including in palatogenesis. The dynamic morphological process of palatal fusion occurs to achieve separation of the nasal and oral cavities. Critically and specifically important in palatal fusion are the medial edge epithelial (MEE) cells, which are initially present at the palatal midline seam and over the course of the palate fusion process are lost from the seam, due to cell migration, epithelial-mesenchymal transition (EMT), and/or programed cell death. In order to define the role of TGF-β signaling during this process, several approaches have been utilized, including a small interfering RNA (siRNA) strategy targeting TGF-β receptors in an organ culture context, the use of genetically engineered mice, such as Wnt1-cre/R26R double transgenic mice, and a cell fate tracing through utilization of cell lineage markers. These approaches have permitted investigators to distinguish some specific traits of well-defined cell populations throughout the palatogenic events. In this paper, we summarize the current understanding on the role of TGF-β signaling, and specifically its association with MEE cell fate during palatal fusion. TGF-β is highly regulated both temporally and spatially, with TGF-β3 and Smad2 being the preferentially expressed signaling molecules in the critical cells of the fusion processes. Interestingly, the accessory receptor, TGF-β type 3 receptor, is also critical for palatal fusion, with evidence for its significance provided by Cre-lox systems and siRNA approaches. This suggests the high demand of ligand for this fine-tuned signaling process. We discuss the new insights in the fate of MEE cells in the midline epithelial seam (MES) during the palate fusion process, with a particular focus on the role of TGF-β signaling.

scholarly journals HGG-12. HUMAN IPSC-DERIVED H3.3K27M NEUROSPHERES: A NOVEL MODEL FOR INVESTIGATING DIPG PATHOGENESIS AND DRUG RESPONSE

2021 ◽  
Vol 23 (Supplement_1) ◽  
pp. i19-i20
Author(s):  
Kasey Skinner ◽  
Tomoyuki Koga ◽  
Shunichiro Miki ◽  
Robert F Gruener ◽  
R Stephanie Huang ◽  
...  
Keyword(s):  
Principal Component ◽  
High Grade Glioma ◽  
Diffuse Intrinsic Pontine Glioma ◽  
Genetically Engineered ◽  
High Grade ◽  
Primary Tumors ◽  
Secondary Tumor ◽  
Immunodeficient Mice

Abstract Diffuse intrinsic pontine glioma (DIPG) is a subset of high-grade glioma that occurs predominantly in children and has no cure. Up to 80% of DIPG harbor a heterozygous point mutation that results in a lysine 27 to methionine substitution in histone variant H3.3 (H3.3K27M). Existing DIPG models have provided insight into the role of H3.3K27M but have limitations: genetically engineered murine models often rely on overexpression of the mutant histone to form tumors; patient-derived xenografts (PDX) are more genetically faithful but preclude examination of the effect of individual mutations on pathogenesis. To address these shortcomings and better recapitulate the genetics of human tumors, we designed a novel DIPG model based on human induced pluripotent stem cells (iPSC) edited via CRISPR to express heterozygous H3.3K27M. Edited iPSC were chemically differentiated into neural progenitor cells, which upon implantation into the brainstems of immunodeficient mice formed diffusely invasive tumors that were histologically consistent with high-grade glioma. Further, neurospheres cultured from primary tumors formed secondary tumors upon reimplantation with more diffuse invasion, suggesting in vivo evolution. To validate this model’s relevance to DIPG transcriptionally, we performed RNA-sequencing on a cohort of primary and secondary tumor neurospheres (termed primary and secondary iDIPG) and compared them to published RNA-seq data from pediatric PDX and patient tumor samples. Hierarchical clustering and principal component analysis on differentially expressed genes (P<0.05) showed that H3.3K27M iDIPG cluster with H3.3K27M PDX and patient tumors. Further, ssGSEA showed that H3.3K27M iDIPG are enriched for astrocytic and mesenchymal signature genes, a defining feature of H3.3K27M DIPG. Finally, we found that primary H3.3K27M iDIPG neurospheres are sensitive to panobinostat, an HDAC inhibitor shown to be effective against H3.3K27M DIPG cells in vitro. Overall, these data suggest that H3.3K27M iDIPG are a promising tool for investigating DIPG biology and new therapeutic strategies.

scholarly journals Toxicity modelling of Plk1-targeted therapies in genetically engineered mice and cultured primary mammalian cells

2011 ◽  
Vol 2 (1) ◽  
Author(s):  
Monika Raab ◽  
Sven Kappel ◽  
Andrea Krämer ◽  
Mourad Sanhaji ◽  
Yves Matthess ◽  
...  
Keyword(s):  
Targeted Therapies ◽  
Mammalian Cells ◽  
Genetically Engineered ◽  
Genetically Engineered Mice

scholarly journals DIPG-19. TARGETING ATM MUTATION IN METASTATIC DIFFUSE MIDLINE GLIOMA – A CASE OF SUSTAINED RESPONSE USING PARP INHIBITOR

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii290-iii291
Author(s):  
Karen Tsui ◽  
Andrew Law ◽  
Michael K Watson
Keyword(s):  
Parp Inhibitor ◽  
Standard Of Care ◽  
High Grade Glioma ◽  
Diffuse Intrinsic Pontine Glioma ◽  
Radiological Criteria ◽  
Metastatic Recurrence ◽  
Curative Therapy ◽  
First Case ◽  
Metastatic Relapse ◽  
Diffuse Midline Glioma

Abstract Diffuse midline glioma (DMG) with H3.3K27M mutation is associated with an extremely poor prognosis, with a median survival of 10 to 12 months. Radiation remains the standard of care however there is no established curative therapy available. We describe a patient diagnosed with a diffuse intrinsic pontine glioma at 5 years of age by clinical and radiological criteria. He was treated with focal radiation 59Gy which resulted in reduction in size of the tumour, and partial improvement of T2 changes on MRI. At 18 months post diagnosis, the patient developed metastatic recurrence at the anterior fornix. This was biopsied and histopathology demonstrated a high grade glioma. Next generation sequencing revealed a H3F3A K27M mutation, and an ATM R3008H mutation. He received whole ventricular radiation 36Gy and boost to the lesion to 45Gy, followed by Olaparib 135mg/m2/day twice daily. He remains in radiological remission 20 months post metastatic relapse and has no organ toxicity to Olaparib. CONCLUSION: H3.3K27M and ATM co-segregating mutations are described in DMG. This is the first case report of targeting ATM mutation with a PARP inhibitor which resulted in prolonged remission of metastatic DMG. Olaparib was well tolerated.

scholarly journals Tenascin-C in Heart Diseases—The Role of Inflammation

2021 ◽  
Vol 22 (11) ◽  
pp. 5828
Author(s):  
Kyoko Imanaka-Yoshida
Keyword(s):  
Ventricular Remodeling ◽  
Heart Diseases ◽  
Genetically Engineered ◽  
Matricellular Protein ◽  
Myocardial Repair ◽  
Inflammatory Reactions ◽  
Tenascin C ◽  
Genetically Engineered Mice

Tenascin-C (TNC) is a large extracellular matrix (ECM) glycoprotein and an original member of the matricellular protein family. TNC is transiently expressed in the heart during embryonic development, but is rarely detected in normal adults; however, its expression is strongly up-regulated with inflammation. Although neither TNC-knockout nor -overexpressing mice show a distinct phenotype, disease models using genetically engineered mice combined with in vitro experiments have revealed multiple significant roles for TNC in responses to injury and myocardial repair, particularly in the regulation of inflammation. In most cases, TNC appears to deteriorate adverse ventricular remodeling by aggravating inflammation/fibrosis. Furthermore, accumulating clinical evidence has shown that high TNC levels predict adverse ventricular remodeling and a poor prognosis in patients with various heart diseases. Since the importance of inflammation has attracted attention in the pathophysiology of heart diseases, this review will focus on the roles of TNC in various types of inflammatory reactions, such as myocardial infarction, hypertensive fibrosis, myocarditis caused by viral infection or autoimmunity, and dilated cardiomyopathy. The utility of TNC as a biomarker for the stratification of myocardial disease conditions and the selection of appropriate therapies will also be discussed from a clinical viewpoint.

scholarly journals IκBα targeting promotes oxidative stress-dependent cell death

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Giovanna Carrà ◽  
Giuseppe Ermondi ◽  
Chiara Riganti ◽  
Luisella Righi ◽  
Giulia Caron ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cell Fate ◽  
Protein Interactions ◽  
In Silico ◽  
Inverse Correlation ◽  
Ros Production ◽  
Gene Encoding ◽  
Specific Expression ◽  
Novel Approach ◽  
Stress Dependent

Abstract Background Oxidative stress is a hallmark of many cancers. The increment in reactive oxygen species (ROS), resulting from an increased mitochondrial respiration, is the major cause of oxidative stress. Cell fate is known to be intricately linked to the amount of ROS produced. The direct generation of ROS is also one of the mechanisms exploited by common anticancer therapies, such as chemotherapy. Methods We assessed the role of NFKBIA with various approaches, including in silico analyses, RNA-silencing and xenotransplantation. Western blot analyses, immunohistochemistry and RT-qPCR were used to detect the expression of specific proteins and genes. Immunoprecipitation and pull-down experiments were used to evaluate protein-protein interactions. Results Here, by using an in silico approach, following the identification of NFKBIA (the gene encoding IκBα) amplification in various cancers, we described an inverse correlation between IκBα, oxidative metabolism, and ROS production in lung cancer. Furthermore, we showed that novel IκBα targeting compounds combined with cisplatin treatment promote an increase in ROS beyond the tolerated threshold, thus causing death by oxytosis. Conclusions NFKBIA amplification and IκBα overexpression identify a unique cancer subtype associated with specific expression profile and metabolic signatures. Through p65-NFKB regulation, IκBα overexpression favors metabolic rewiring of cancer cells and distinct susceptibility to cisplatin. Lastly, we have developed a novel approach to disrupt IκBα/p65 interaction, restoring p65-mediated apoptotic responses to cisplatin due to mitochondria deregulation and ROS-production.

scholarly journals Characterization and visualization of murine coagulation factor VIII-producing cells in vivo

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Morisada Hayakawa ◽  
Asuka Sakata ◽  
Hiroko Hayakawa ◽  
Hikari Matsumoto ◽  
Takafumi Hiramoto ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Factor Viii ◽  
Fluorescent Protein ◽  
Coagulation Factor ◽  
Coagulation Factors ◽  
Genetically Engineered ◽  
Coagulation Factor Viii ◽  
Liver Sinusoidal Endothelial Cells ◽  
Genetically Engineered Mice

AbstractCoagulation factors are produced from hepatocytes, whereas production of coagulation factor VIII (FVIII) from primary tissues and cell species is still controversial. Here, we tried to characterize primary FVIII-producing organ and cell species using genetically engineered mice, in which enhanced green fluorescent protein (EGFP) was expressed instead of the F8 gene. EGFP-positive FVIII-producing cells existed only in thin sinusoidal layer of the liver and characterized as CD31high, CD146high, and lymphatic vascular endothelial hyaluronan receptor 1 (Lyve1)+. EGFP-positive cells can be clearly distinguished from lymphatic endothelial cells in the expression profile of the podoplanin− and C-type lectin-like receptor-2 (CLEC-2)+. In embryogenesis, EGFP-positive cells began to emerge at E14.5 and subsequently increased according to liver maturation. Furthermore, plasma FVIII could be abolished by crossing F8 conditional deficient mice with Lyve1-Cre mice. In conclusion, in mice, FVIII is only produced from endothelial cells exhibiting CD31high, CD146high, Lyve1+, CLEC-2+, and podoplanin− in liver sinusoidal endothelial cells.

scholarly journals Crosstalk between MUC1 and VEGF in angiogenesis and metastasis: a review highlighting roles of the MUC1 with an emphasis on metastatic and angiogenic signaling

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Farnaz Khodabakhsh ◽  
Parnaz Merikhian ◽  
Mohammad Reza Eisavand ◽  
Leila Farahmand
Keyword(s):  
Tumor Growth ◽  
Signaling Pathways ◽  
Cell Fate ◽  
Endothelial Cell Proliferation ◽  
Mucin 1 ◽  
Signaling Transduction ◽  
Growth And Survival ◽  
Angiogenic Proteins ◽  
Angiogenic Effect ◽  
And Migration

AbstractVEGF and its receptor family (VEGFR) members have unique signaling transduction system that play significant roles in most pathological processes, such as angiogenesis in tumor growth and metastasis. VEGF-VEGFR complex is a highly specific mitogen for endothelial cells and any de-regulation of the angiogenic balance implicates directly in endothelial cell proliferation and migration. Moreover, it has been shown that overexpressing Mucin 1 (MUC1) on the surface of many tumor cells resulting in upregulation of numerous signaling transduction cascades, such as growth and survival signaling pathways related to RTKs, loss of cell-cell and cell-matrix adhesion, and EMT. It promotes gene transcription of pro-angiogenic proteins such as HIF-1α during periods of oxygen scarcity (hypoxia) to enhance tumor growth and angiogenesis stimulation. In contrast, the cytoplasmic domain of MUC1 (MUC1-C) inhibits apoptosis, which in turn, impresses upon cell fate. Besides, it has been established that reduction in VEGF expression level correlated with silencing MUC1-C level indicating the anti-angiogenic effect of MUC1 downregulation. This review enumerates the role of MUC1-C oncoprotein and VEGF in angiogenesis and metastasis and describes several signaling pathways by which MUC1-C would mediate the pro-angiogenic activities of cancer cells.

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