scholarly journals Opposite regulation of Wnt/β-catenin and Shh signaling pathways by Rack1 controls mammalian cerebellar development

2019 ◽  
Vol 116 (10) ◽  
pp. 4661-4670 ◽  
Author(s):  
Haihong Yang ◽  
Qian Zhu ◽  
Juanxian Cheng ◽  
Yan Wu ◽  
Ming Fan ◽  
...  
Keyword(s):  
Signaling Pathways ◽  
Molecular Mechanisms ◽  
Treatment Options ◽  
Adaptor Protein ◽  
Cerebellar Development ◽  
Shh Signaling ◽  
Histone Deacetylase 1 ◽  
Complex Development ◽  
A Cell ◽  
Fissure Formation

The development of the cerebellum depends on intricate processes of neurogenesis, migration, and differentiation of neural stem cells (NSCs) and progenitor cells. Defective cerebellar development often results in motor dysfunctions and psychiatric disorders. Understanding the molecular mechanisms that underlie the complex development of the cerebellum will facilitate the development of novel treatment options. Here, we report that the receptor for activated C kinase (Rack1), a multifaceted signaling adaptor protein, regulates mammalian cerebellar development in a cell type-specific manner. Selective deletion of Rack1 in mouse NSCs or granule neuron progenitors (GNPs), but not Bergmann glial cells (BGs), causes severe defects in cerebellar morphogenesis, including impaired folia and fissure formation. NSCs and GNPs lacking Rack1 exhibit enhanced Wnt/β-catenin signaling but reduced Sonic hedgehog (Shh) signaling. Simultaneous deletion of β-catenin in NSCs, but not GNPs, significantly rescues theRack1mutant phenotype. Interestingly, Rack1 controls the activation of Shh signaling by regulating the ubiquitylation and stability of histone deacetylase 1 (HDAC1)/HDAC2. Suppression of HDAC1/HDAC2 activity in the developing cerebellum phenocopies theRack1mutant. Together, these results reveal a previously unknown role of Rack1 in controlling mammalian cerebellar development by opposite regulation of Wnt/β-catenin and Shh signaling pathways.

Adaptor Protein Lnk Negatively Regulates Mutant MPL and JAK2 Alleles Associated with Myeloproliferative Disorders

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 1531-1531
Author(s):  
Sigal Gery ◽  
Saskia Gueller ◽  
Julia Sohn ◽  
Shayne Nabavinouri ◽  
Amanda Leiter ◽  
...  
Keyword(s):  
Signaling Pathways ◽  
Molecular Mechanisms ◽  
Bone Marrow Cells ◽  
Adaptor Protein ◽  
Myeloproliferative Disorders ◽  
Sh2 Domain ◽  
Cytokine Receptor ◽  
Negative Regulator ◽  
Activating Mutations ◽  
Signaling Axis

Abstract Activating mutations in the cytokine receptor/JAK2 signaling axis are found at high frequency in myeloproliferative disorders (MPD). Lnk, an SH2-containing adaptor protein, is a negative regulator of several hematopoietic cytokine receptors including MPL and EpoR. Here, we assessed whether Lnk can attenuate the activity of mutant MPLW515L, JAK2V617F and JAK2K539L found in MPD patients. Lnk overexpression in Ba/F3-MPLW515L cells inhibited cytokine-independent growth, while suppression of Lnk in UT7-MPLW515L cells enhanced proliferation. Lnk-mediated growth inhibition was associated with downregulation of JAK/STAT, MAPK and PI3K signaling pathways. Similarly, Lnk inhibited cytokine-independent growth conferred by JAK2V617F and JAK2K539L in Ba/F3-EpoR cells. Following thrombopoietin stimulation, Lnk became tyrosyl-phosphorylated and associated with activated wild-type (WT) MPL and MPLW515L at the plasma membrane of Ba/F3 cells. An SH2 mutant Lnk (R392E) failed to bind and inhibit WT MPL and MPLW515L, demonstrating that the SH2 domain is essential for Lnk down-modulation of the receptors. The Lnk-MPL interaction was also detected with endogenously expressed proteins from cultured bone marrow cells. A series of C-terminally truncated Lnk constructs were used to determine which Lnk regions are required for Lnk inhibition of JAK2. Experiments in 293T cells indicated that Lnk SH2 domain binds to phosphorylated JAK2. In addition, other Lnk regions associated with non-phosphorylated JAK2, and these interactions were critical for Lnk inhibition of JAK2V617F and JAK2K539L constitutive activation. Our data suggest a model wherein Lnk downregulation of the receptor/JAK2 signaling involves two mechanisms; one is inhibition of the cytokine receptor utilizing JAK2, the second is direct suppression of JAK2 kinase activity. Furthermore, while the receptor mediated inhibition requires the SH2 domain, direct inhibition of JAK2 mutants, V617F and K539L, relies on other Lnk domains. Further elucidating the molecular mechanisms underlying Lnk inhibition of signaling pathways abnormally activated by oncogenic alleles, will provide insight into the pathogenesis of MPD and may have therapeutic value.

scholarly journals Whole-Genome Analysis of De Novo Somatic Point Mutations Reveals Novel Mutational Biomarkers in Pancreatic Cancer

Cancers ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 4376
Author(s):  
Amin Ghareyazi ◽  
Amir Mohseni ◽  
Hamed Dashti ◽  
Amin Beheshti ◽  
Abdollah Dehzangi ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Signaling Pathways ◽  
Molecular Mechanisms ◽  
De Novo ◽  
Treatment Options ◽  
Point Mutations ◽  
Growth Factor Receptor ◽  
Causative Mutation ◽  
Whole Genome Analysis ◽  
Cancer Subtypes

It is now known that at least 10% of samples with pancreatic cancers (PC) contain a causative mutation in the known susceptibility genes, suggesting the importance of identifying cancer-associated genes that carry the causative mutations in high-risk individuals for early detection of PC. In this study, we develop a statistical pipeline using a new concept, called gene-motif, that utilizes both mutated genes and mutational processes to identify 4211 3-nucleotide PC-associated gene-motifs within 203 significantly mutated genes in PC. Using these gene-motifs as distinguishable features for pancreatic cancer subtyping results in identifying five PC subtypes with distinguishable phenotypes and genotypes. Our comprehensive biological characterization reveals that these PC subtypes are associated with different molecular mechanisms including unique cancer related signaling pathways, in which for most of the subtypes targeted treatment options are currently available. Some of the pathways we identified in all five PC subtypes, including cell cycle and the Axon guidance pathway are frequently seen and mutated in cancer. We also identified Protein kinase C, EGFR (epidermal growth factor receptor) signaling pathway and P53 signaling pathways as potential targets for treatment of the PC subtypes. Altogether, our results uncover the importance of considering both the mutation type and mutated genes in the identification of cancer subtypes and biomarkers.

scholarly journals An Investigation of Point Mutations Discovers Novel Genes and Their Corresponding Motifs in Pancreatic Cancer

2021 ◽  
Author(s):  
Amin Ghareyazi ◽  
Amir Mohseni ◽  
Hamed Dashti ◽  
Abdollah Dehzangi ◽  
Hamid R. Rabiee ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Signaling Pathways ◽  
Molecular Mechanisms ◽  
Treatment Options ◽  
Point Mutations ◽  
Growth Factor Receptor ◽  
Causative Mutation ◽  
Cancer Subtypes ◽  
P53 Signaling ◽  
Pancreatic Cancers

It has now known that at least 10% of samples with pancreatic cancers (PC) contain a causative mutation in the known susceptibility genes, suggesting the importance of identifying cancer-associated genes that carry the causative mutations in high-risk individuals for early detection of PC. In this study, we develop a statistical pipeline using a new concept, called gene-motif, that utilizes both mutated genes and mutational processes to identify 4,211 3-nucleotide PC-associated gene-motifs within 203 significantly mutated genes in PC. Using these gene-motifs as distinguishable features for pancreatic cancer subtyping results in identifying five PC subtypes with distinguishable phenotypes and genotypes. Our comprehensive biological characterization reveals that these PC subtypes are associated with different molecular mechanisms including unique cancer related signaling pathways, in which for most of the subtypes targeted treatment options are currently available. Some of the pathways we identified in all five PC subtypes, including cell cycle and the Axon guidance pathway are frequently seen and mutated in cancer. We also identified Protein kinase C, EGFR (epidermal growth factor receptor) signaling pathway and P53 signaling pathways as potential targets for treatment of the PC subtypes. Altogether, our results uncover the importance of considering both the mutation type and mutated genes in the identification of cancer subtypes and biomarkers.

scholarly journals Novel strategies for treatment of pulmonary arterial hypertension

2017 ◽  
Vol 71 (1) ◽  
pp. 0-0
Author(s):  
Magdalena Jasińska-Stroschein ◽  
Daria Orszulak-Michalak
Keyword(s):  
Pulmonary Arterial Hypertension ◽  
Arterial Hypertension ◽  
Signaling Pathways ◽  
Molecular Mechanisms ◽  
Combined Therapy ◽  
Treatment Options ◽  
Premature Death ◽  
Right Heart Failure ◽  
Phosphodiesterase Type 5 Inhibitors ◽  
Pulmonary Arterial

Pulmonary hypertension (PH) is a rare disorder associated with abnormally elevated pulmonary pressures that, if untreated, leads to right heart failure and premature death. Special population include patents with pulmonary arterial hypertension (PAH). A greater understanding of the epidemiology, pathogenesis, and pathophysiology of PAH has led to significant advances over the past few years. Modern drug therapy provides a significant improvement in patient symptomatic status and a slower rate of clinical deterioration. Despite this, PAH remains a chronic disease without a cure. There is a need for the development of novel therapies and therapeutic strategies, as treatment options are neither universally available nor always effective, possibly due to the large number of mediator and signaling pathways with downstream effectors which are implicated in the pathobiology of PH, and which are not fully reversed during PAH therapy. In the following pages, we review novel strategies for treatment of PAH. For this purpose we summarized the role of specific drug therapies that involve: endothelin receptor antagonists (ERA), phosphodiesterase type 5 inhibitors (PDE-5i) and prostacyclin and prostanoids (PGI2). We focused on novel molecular mechanisms in PAH of recently approved: Guanylate cyclase stimulator and non-prostanoid IP receptor agonist. We discussed novel approach to combined therapy, as well as a new generation of investigational drugs and promising PAH-associated signaling pathways, such as, PDGF, RhoA/ROCK RAAS, HT-5 and others.

scholarly journals Potential Role of the Inflammasome-Derived Inflammatory Cytokines in Pulmonary Fibrosis

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Rupa Biswas ◽  
Melisa Bunderson-Schelvan ◽  
Andrij Holian
Keyword(s):  
Pulmonary Fibrosis ◽  
Molecular Mechanisms ◽  
Treatment Options ◽  
Adaptor Protein ◽  
Adaptive Immune ◽  
Fibrotic Process ◽  
Future Drug ◽  
The Usa ◽  
Adaptive Immune Systems

Pulmonary fibrosis is a progressive, disabling disease with mortality rates that appear to be increasing in the western population, including the USA. There are over 140 known causes of pulmonary fibrosis as well as many unknown causes. Treatment options for this disease are limited due to poor understanding of the molecular mechanisms of the disease progression. However, recent progress in inflammasome research has greatly contributed to our understanding of its role in inflammation and fibrosis development. The inflammasome is a multiprotein complex that is an important component of both the innate and adaptive immune systems. Activation of proinflammatory cytokines following inflammasome assembly, such as IL-1βand IL-18, has been associated with development of PF. In addition, components of the inflammasome complex itself, such as the adaptor protein ASC have been associated with PF development. Recent evidence suggesting that the fibrotic process can be reversed via blockade of pathways associated with inflammasome activity may provide hope for future drug strategies. In this paper we will give an introduction to pulmonary fibrosis and its known causes. In addition, we will discuss the importance of the inflammasome in the development of pulmonary fibrosis as well as discuss potential future treatment options.

Wnt/beta-catenin and PI3K/Akt/mTOR Signaling Pathways in Glioblastoma: Two Main Targets for Drug Design: A Review

2020 ◽  
Vol 26 (15) ◽  
pp. 1729-1741 ◽  
Author(s):  
Seyed H. Shahcheraghi ◽  
Venant Tchokonte-Nana ◽  
Marzieh Lotfi ◽  
Malihe Lotfi ◽  
Ahmad Ghorbani ◽  
...  
Keyword(s):  
Signaling Pathways ◽  
Molecular Mechanisms ◽  
Cellular Proliferation ◽  
Chemotherapy Resistance ◽  
Wnt Signaling Pathway ◽  
Therapeutic Interventions ◽  
Beta Catenin ◽  
Clinical Prognosis ◽  
Invasion And Migration ◽  
And Migration

: Glioblastoma (GBM) is the most common and malignant astrocytic glioma, accounting for about 90% of all brain tumors with poor prognosis. Despite recent advances in understanding molecular mechanisms of oncogenesis and the improved neuroimaging technologies, surgery, and adjuvant treatments, the clinical prognosis of patients with GBM remains persistently unfavorable. The signaling pathways and the regulation of growth factors of glioblastoma cells are very abnormal. The various signaling pathways have been suggested to be involved in cellular proliferation, invasion, and glioma metastasis. The Wnt signaling pathway with its pleiotropic functions in neurogenesis and stem cell proliferation is implicated in various human cancers, including glioma. In addition, the PI3K/Akt/mTOR pathway is closely related to growth, metabolism, survival, angiogenesis, autophagy, and chemotherapy resistance of GBM. Understanding the mechanisms of GBM’s invasion, represented by invasion and migration, is an important tool in designing effective therapeutic interventions. This review will investigate two main signaling pathways in GBM: PI3K/Akt/mTOR and Wnt/beta-catenin signaling pathways.

Melatonin As a Modulator of Degenerative and Regenerative Signaling Pathways in Injured Retinal Ganglion Cells

2019 ◽  
Vol 25 (28) ◽  
pp. 3057-3073 ◽  
Author(s):  
Kobra B. Juybari ◽  
Azam Hosseinzadeh ◽  
Habib Ghaznavi ◽  
Mahboobeh Kamali ◽  
Ahad Sedaghat ◽  
...  
Keyword(s):  
Optic Nerve ◽  
Mitochondrial Dysfunction ◽  
Signaling Pathways ◽  
Retinal Ganglion Cells ◽  
Molecular Mechanisms ◽  
Nitrosative Stress ◽  
Ganglion Cells ◽  
Axon Growth ◽  
Nerve Fibers ◽  
Retinal Ganglion

Optic neuropathies refer to the dysfunction or degeneration of optic nerve fibers caused by any reasons including ischemia, inflammation, trauma, tumor, mitochondrial dysfunction, toxins, nutritional deficiency, inheritance, etc. Post-mitotic CNS neurons, including retinal ganglion cells (RGCs) intrinsically have a limited capacity for axon growth after either trauma or disease, leading to irreversible vision loss. In recent years, an increasing number of laboratory evidence has evaluated optic nerve injuries, focusing on molecular signaling pathways involved in RGC death. Trophic factor deprivation (TFD), inflammation, oxidative stress, mitochondrial dysfunction, glutamate-induced excitotoxicity, ischemia, hypoxia, etc. have been recognized as important molecular mechanisms leading to RGC apoptosis. Understanding these obstacles provides a better view to find out new strategies against retinal cell damage. Melatonin, as a wide-spectrum antioxidant and powerful freeradical scavenger, has the ability to protect RGCs or other cells against a variety of deleterious conditions such as oxidative/nitrosative stress, hypoxia/ischemia, inflammatory processes, and apoptosis. In this review, we primarily highlight the molecular regenerative and degenerative mechanisms involved in RGC survival/death and then summarize the possible protective effects of melatonin in the process of RGC death in some ocular diseases including optic neuropathies. Based on the information provided in this review, melatonin may act as a promising agent to reduce RGC death in various retinal pathologic conditions.

Vitamin C as an Anticancer Agent: Regulation of Signaling Pathways

2020 ◽  
Vol 20 (21) ◽  
pp. 1868-1875
Author(s):  
Ghazala Butt ◽  
Ammad A. Farooqi ◽  
Aima Adylova ◽  
Rukset Attar ◽  
Seher Yilmaz ◽  
...  
Keyword(s):  
Vitamin C ◽  
Cancer Cells ◽  
Signaling Pathways ◽  
Scientific Evidence ◽  
Treatment Options ◽  
Published Data ◽  
New Era ◽  
Molecular Oncology ◽  
Anticancer Effects ◽  
Oncogenic Pathways

Treatment options for effective treatment of cancer with minimum off-target effects and maximum clinical outcomes have remained overarching goals in the clinical oncology. Vitamin C has remained in the shadows of controversy since the past few decades; burgeoning evidence has started to shed light on wide-ranging anticancer effects exerted by Vitamin C to induce apoptosis in drug-resistant cancer cells, inhibit uncontrolled proliferation of the cancer cells and metastatic spread. Landmark achievements in molecular oncology have ushered in a new era, and researchers have focused on the identification of oncogenic pathways regulated by Vitamin C in different cancers. However, there are visible knowledge gaps in our understanding related to the ability of Vitamin C to modulate a myriad of transduction cascades. There are scattered pieces of scientific evidence about promising potential of Vitamin C to regulate JAK-STAT, TGF/SMAD, TRAIL and microRNAs in different cancers. However, published data is insufficient and needs to be investigated comprehensively to enable basic and clinical researchers to reap full benefits and promote result-oriented transition of Vitamin C into various phases of clinical trials. In this review, we will emphasize on available evidence related to the regulation of oncogenic cell signaling pathways by Vitamin C in different cancers. We will also highlight the conceptual gaps, which need detailed and cutting-edge research.

The Protective Effects of Green Tea Catechins in the Management of Neurodegenerative Diseases: A Review

2019 ◽  
Vol 16 (1) ◽  
pp. 57-65 ◽  
Author(s):  
Tahereh Farkhondeh ◽  
Hanieh Shaterzadeh Yazdi ◽  
Saeed Samarghandian
Keyword(s):  
Neurodegenerative Diseases ◽  
Signaling Pathways ◽  
Green Tea ◽  
Molecular Mechanisms ◽  
Main Role ◽  
Related Factor ◽  
Protective Effects ◽  
Tea Catechins ◽  
Green Tea Catechins ◽  
And Control

Background: The therapeutic strategies to manage neurodegenerative diseases remain limited and it is necessary to discover new agents for their prevention and control. Oxidative stress and inflammation play a main role in the pathogenesis of neurodegenerative diseases. The aim of this study is to review the effects of green tea catechins against the Neurodegenerative Diseases. Methods: In this study, we extensively reviewed all articles on the terms of Green tea, catechins, CNS disorders, and different diseases in PubMed, Science Direct, Scopus, and Google Scholar databases between the years 1990 and 2017. Results: The present study found that catechins, the major flavonoids in green tea, are powerful antioxidants and radical scavengers which possess the potential roles in the management of neurodegenerative diseases. Catechins modulate the cellular and molecular mechanisms through the inflammation-related NF-&amp;#954;B and the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathways. Conclusion: The findings of the present review shows catechins could be effective against neurodegenerative diseases due to their antioxidation and anti-inflammation effects and the involved biochemical pathways including Nrf2 and NF-kB signaling pathways.<P&gt;

The Signaling Pathways in Nitric Oxide Production by Neutrophils Exposed to N-nitrosodimethylamine

2018 ◽  
Vol 16 (2) ◽  
pp. 194-199
Author(s):  
Wioletta Ratajczak-Wrona ◽  
Ewa Jablonska
Keyword(s):  
Nitric Oxide ◽  
Signaling Pathways ◽  
Molecular Mechanisms ◽  
Polymorphonuclear Neutrophils ◽  
Microbial Pathogens ◽  
Human Neutrophils ◽  
No Production ◽  
Oxide Synthase ◽  
Inducible Nitric Oxide

Background: Polymorphonuclear neutrophils (PMNs) play a crucial role in the innate immune system’s response to microbial pathogens through the release of reactive nitrogen species, including Nitric Oxide (NO). </P><P> Methods: In neutrophils, NO is produced by the inducible Nitric Oxide Synthase (iNOS), which is regulated by various signaling pathways and transcription factors. N-nitrosodimethylamine (NDMA), a potential human carcinogen, affects immune cells. NDMA plays a major part in the growing incidence of cancers. Thanks to the increasing knowledge on the toxicological role of NDMA, the environmental factors that condition the exposure to this compound, especially its precursors- nitrates arouse wide concern. Results: In this article, we present a detailed summary of the molecular mechanisms of NDMA’s effect on the iNOS-dependent NO production in human neutrophils. Conclusion: This research contributes to a more complete understanding of the mechanisms that explain the changes that occur during nonspecific cellular responses to NDMA toxicity.

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