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1.
Hematology ; 29(1): 2356292, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38785187

ABSTRACT

OBJECTIVES: This study aims to investigate the role of excessive Protein Tyrosine Phosphatase Non-Receptor Type 21 (PTPN21) in the proliferation of Acute Lymphoblastic Leukemia (ALL) cells with EGF stimulation. METHODS: PTPN21 was overexpressed in ALL cell lines by lentiviral transfection. Apoptosis was assayed by Annexin V/7-AAD staining. The proliferation and cell cycle of EGF-treated ALL cells were assessed by MTT and Ki-67/7-AAD staining respectively. The phosphorylation of Src tyrosine kinase and mediators of distinct MAPK pathways were assessed by Western blot. RESULTS: Overexpression of PTPN21 had minimal effect on the apoptosis of ALL cells, but significantly promoted the proliferation and cell cycle progression of ALL cells stimulated with EGF. The activity of Src tyrosine kinase and the MAPK pathways was elevated. Inhibition of MAPK pathways by specific inhibitors mitigated this pro-proliferative effect of excessive PTPN21 on EGF-stimulated ALL cells. CONCLUSION: PTPN21 may facilitate ALL progression by promoting cell proliferation via the Src/MAPK signaling pathways.


Subject(s)
Cell Proliferation , Epidermal Growth Factor , MAP Kinase Signaling System , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Protein Tyrosine Phosphatases, Non-Receptor , Humans , Apoptosis/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Epidermal Growth Factor/pharmacology , MAP Kinase Signaling System/drug effects , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/metabolism , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Protein Tyrosine Phosphatases, Non-Receptor/genetics , Protein Tyrosine Phosphatases, Non-Receptor/metabolism
2.
Pharmacol Res ; 205: 107236, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38797358

ABSTRACT

The rapid antidepressant effects of ketamine depend on the N-methyl-D-aspartate (NMDA) receptor containing 2B subunit (NR2B), whose function is influenced by its phosphorylated regulation and distribution within and outside synapses. It remains unclear if ketamine's rapid onset of antidepressant effects relies on the dynamic phosphorylated regulation of NR2B within and outside synapses. Here, we show that ketamine rapidlyalleviated depression-like behaviors and normalized abnormal expression of pTyr1472NR2B and striatal-enriched protein tyrosine phosphatase (STEP) 61 within and outside synapses in the medial prefrontal cortex (mPFC) induced by chronic unpredictable stress (CUS) and conditional knockdown of STEP 61, a key phosphatase of NR2B, within 1 hour after administration Together, our results delineate the rapid initiation of ketamine's antidepressant effects results from the restoration of NR2B phosphorylation homeostasis within and outside synapses. The dynamic regulation of phosphorylation of NR2B provides a new perspective for developing new antidepressant strategies.


Subject(s)
Antidepressive Agents , Depression , Ketamine , Mice, Inbred C57BL , Prefrontal Cortex , Receptors, N-Methyl-D-Aspartate , Receptors, N-Methyl-D-Aspartate/metabolism , Ketamine/pharmacology , Animals , Phosphorylation/drug effects , Antidepressive Agents/pharmacology , Antidepressive Agents/therapeutic use , Male , Prefrontal Cortex/metabolism , Prefrontal Cortex/drug effects , Depression/drug therapy , Depression/metabolism , Protein Tyrosine Phosphatases, Non-Receptor/metabolism , Protein Tyrosine Phosphatases, Non-Receptor/genetics , Tyrosine/metabolism , Mice , Stress, Psychological/metabolism , Stress, Psychological/drug therapy , Synapses/drug effects , Synapses/metabolism , Behavior, Animal/drug effects
3.
Proc Natl Acad Sci U S A ; 121(23): e2217971121, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38805272

ABSTRACT

Myogenesis is a multistep process that requires a spatiotemporal regulation of cell events resulting finally in myoblast fusion into multinucleated myotubes. Most major insights into the mechanisms underlying fusion seem to be conserved from insects to mammals and include the formation of podosome-like protrusions (PLPs) that exert a driving force toward the founder cell. However, the machinery that governs this process remains poorly understood. In this study, we demonstrate that MTM1 is the main enzyme responsible for the production of phosphatidylinositol 5-phosphate, which in turn fuels PI5P 4-kinase α to produce a minor and functional pool of phosphatidylinositol 4,5-bisphosphate that concentrates in PLPs containing the scaffolding protein Tks5, Dynamin-2, and the fusogenic protein Myomaker. Collectively, our data reveal a functional crosstalk between a PI-phosphatase and a PI-kinase in the regulation of PLP formation.


Subject(s)
Cell Fusion , Myoblasts , Phosphatidylinositol Phosphates , Podosomes , Animals , Phosphatidylinositol Phosphates/metabolism , Mice , Myoblasts/metabolism , Myoblasts/cytology , Podosomes/metabolism , Protein Tyrosine Phosphatases, Non-Receptor/metabolism , Protein Tyrosine Phosphatases, Non-Receptor/genetics , Muscle Development/physiology
4.
J Med Chem ; 67(11): 8817-8835, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38768084

ABSTRACT

Together with protein tyrosine kinases, protein tyrosine phosphatases (PTPs) control protein tyrosine phosphorylation and regulate numerous cellular functions. Dysregulated PTP activity is associated with the onset of multiple human diseases. Nevertheless, understanding of the physiological function and disease biology of most PTPs remains limited, largely due to the lack of PTP-specific chemical probes. In this study, starting from a well-known nonhydrolyzable phosphotyrosine (pTyr) mimetic, phosphonodifluoromethyl phenylalanine (F2Pmp), we synthesized 7 novel phosphonodifluoromethyl-containing bicyclic/tricyclic aryl derivatives with improved cell permeability and potency toward various PTPs. Furthermore, with fragment- and structure-based design strategies, we advanced compound 9 to compound 15, a first-in-class, potent, selective, and bioavailable inhibitor of human CDC14A and B phosphatases. This study demonstrates the applicability of the fragment-based design strategy in creating potent, selective, and bioavailable PTP inhibitors and provides a valuable probe for interrogating the biological roles of hCDC14 phosphatases and assessing their potential for therapeutic interventions.


Subject(s)
Enzyme Inhibitors , Phosphotyrosine , Humans , Phosphotyrosine/metabolism , Phosphotyrosine/chemistry , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/chemical synthesis , Structure-Activity Relationship , Protein Tyrosine Phosphatases, Non-Receptor/antagonists & inhibitors , Protein Tyrosine Phosphatases, Non-Receptor/metabolism , Protein Tyrosine Phosphatases, Non-Receptor/chemistry , Protein Tyrosine Phosphatases/antagonists & inhibitors , Protein Tyrosine Phosphatases/metabolism , Molecular Structure , Biological Availability
5.
Biochim Biophys Acta Mol Cell Res ; 1871(5): 119739, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38710289

ABSTRACT

The myotubularin family, encompassing myotubularin 1 (MTM1) and 14 myotubularin-related proteins (MTMRs), represents a conserved group of phosphatases featuring a protein tyrosine phosphatase domain. Nine members are characterized by an active phosphatase domain C(X)5R, dephosphorylating the D3 position of PtdIns(3)P and PtdIns(3,5)P2. Mutations in myotubularin genes result in human myopathies, and several neuropathies including X-linked myotubular myopathy and Charcot-Marie-Tooth type 4B. MTM1, MTMR6 and MTMR14 also contribute to Ca2+ signaling and Ca2+ homeostasis that play a key role in many MTM-dependent myopathies and neuropathies. Here we explore the evolving roles of MTM1/MTMRs, unveiling their influence on critical aspects of Ca2+ signaling pathways.


Subject(s)
Calcium Signaling , Calcium , Homeostasis , Protein Tyrosine Phosphatases, Non-Receptor , Humans , Protein Tyrosine Phosphatases, Non-Receptor/metabolism , Protein Tyrosine Phosphatases, Non-Receptor/genetics , Calcium/metabolism , Animals , Myopathies, Structural, Congenital/genetics , Myopathies, Structural, Congenital/metabolism , Mutation
6.
J Biol Chem ; 300(5): 107271, 2024 May.
Article in English | MEDLINE | ID: mdl-38588813

ABSTRACT

Lafora disease (LD) is an autosomal recessive myoclonus epilepsy with onset in the teenage years leading to death within a decade of onset. LD is characterized by the overaccumulation of hyperphosphorylated, poorly branched, insoluble, glycogen-like polymers called Lafora bodies. The disease is caused by mutations in either EPM2A, encoding laforin, a dual specificity phosphatase that dephosphorylates glycogen, or EMP2B, encoding malin, an E3-ubiquitin ligase. While glycogen is a widely accepted laforin substrate, substrates for malin have been difficult to identify partly due to the lack of malin antibodies able to detect malin in vivo. Here we describe a mouse model in which the malin gene is modified at the C-terminus to contain the c-myc tag sequence, making an expression of malin-myc readily detectable. Mass spectrometry analyses of immunoprecipitates using c-myc tag antibodies demonstrate that malin interacts with laforin and several glycogen-metabolizing enzymes. To investigate the role of laforin in these interactions we analyzed two additional mouse models: malin-myc/laforin knockout and malin-myc/LaforinCS, where laforin was either absent or the catalytic Cys was genomically mutated to Ser, respectively. The interaction of malin with partner proteins requires laforin but is not dependent on its catalytic activity or the presence of glycogen. Overall, the results demonstrate that laforin and malin form a complex in vivo, which stabilizes malin and enhances interaction with partner proteins to facilitate normal glycogen metabolism. They also provide insights into the development of LD and the rescue of the disease by the catalytically inactive phosphatase.


Subject(s)
Lafora Disease , Protein Tyrosine Phosphatases, Non-Receptor , Ubiquitin-Protein Ligases , Lafora Disease/metabolism , Lafora Disease/genetics , Lafora Disease/pathology , Animals , Mice , Ubiquitin-Protein Ligases/metabolism , Ubiquitin-Protein Ligases/genetics , Protein Tyrosine Phosphatases, Non-Receptor/metabolism , Protein Tyrosine Phosphatases, Non-Receptor/genetics , Humans , Dual-Specificity Phosphatases/metabolism , Dual-Specificity Phosphatases/genetics , Disease Models, Animal , Glycogen/metabolism , Glycogen/genetics
7.
FASEB J ; 38(8): e23590, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38656553

ABSTRACT

Studies have suggested that microglial IL-6 modulates inflammatory pain; however, the exact mechanism of action remains unclear. We therefore hypothesized that PKCε and MEG2 competitively bind to STAT3 and contribute to IL-6-mediated microglial hyperalgesia during inflammatory pain. Freund's complete adjuvant (FCA) and lipopolysaccharide (LPS) were used to induce hyperalgesia model mice and microglial inflammation. Mechanical allodynia was evaluated using von Frey tests in vivo. The interaction among PKCε, MEG2, and STAT3 was determined using ELISA and immunoprecipitation assay in vitro. The PKCε, MEG2, t-STAT3, pSTAT3Tyr705, pSTAT3Ser727, IL-6, GLUT3, and TREM2 were assessed by Western blot. IL-6 promoter activity and IL-6 concentration were examined using dual luciferase assays and ELISA. Overexpression of PKCε and MEG2 promoted and attenuated inflammatory pain, accompanied by an increase and decrease in IL-6 expression, respectively. PKCε displayed a stronger binding ability to STAT3 when competing with MEG2. STAT3Ser727 phosphorylation increased STAT3 interaction with both PKCε and MEG2. Moreover, LPS increased PKCε, MEG2, pSTAT3Tyr705, pSTAT3Ser727, IL-6, and GLUT3 levels and decreased TREM2 during microglia inflammation. IL-6 promoter activity was enhanced or inhibited by PKCε or MEG2 in the presence of STAT3 and LPS stimulation, respectively. In microglia, overexpression of PKCε and/or MEG2 resulted in the elevation of tSTAT3, pSTAT3Tyr705, pSTAT3Ser727, IL-6, and TREM2, and the reduction of GLUT3. PKCε is more potent than MEG2 when competitively binding to STAT3, displaying dual modulatory effects of IL-6 production, thus regulating the GLUT3 and TREM2 in microglia during inflammatory pain sensation.


Subject(s)
Hyperalgesia , Inflammation , Interleukin-6 , Microglia , Protein Kinase C-epsilon , STAT3 Transcription Factor , Animals , Male , Mice , Freund's Adjuvant , Hyperalgesia/metabolism , Inflammation/metabolism , Interleukin-6/metabolism , Interleukin-6/genetics , Lipopolysaccharides/toxicity , Lipopolysaccharides/pharmacology , Membrane Glycoproteins/metabolism , Membrane Glycoproteins/genetics , Mice, Inbred C57BL , Microglia/metabolism , Pain/metabolism , Phosphorylation , Protein Binding , Protein Kinase C-epsilon/metabolism , Protein Kinase C-epsilon/genetics , Receptors, Immunologic/metabolism , Receptors, Immunologic/genetics , STAT3 Transcription Factor/metabolism , Protein Tyrosine Phosphatases, Non-Receptor/metabolism
8.
Cancer Lett ; 588: 216783, 2024 Apr 28.
Article in English | MEDLINE | ID: mdl-38462034

ABSTRACT

Inhibition of K-RAS effectors like B-RAF or MEK1/2 is accompanied by treatment resistance in cancer patients via re-activation of PI3K and Wnt signaling. We hypothesized that myotubularin-related-protein-7 (MTMR7), which inhibits PI3K and ERK1/2 signaling downstream of RAS, directly targets RAS and thereby prevents resistance. Using cell and structural biology combined with animal studies, we show that MTMR7 binds and inhibits RAS at cellular membranes. Overexpression of MTMR7 reduced RAS GTPase activities and protein levels, ERK1/2 phosphorylation, c-FOS transcription and cancer cell proliferation in vitro. We located the RAS-inhibitory activity of MTMR7 to its charged coiled coil (CC) region and demonstrate direct interaction with the gastrointestinal cancer-relevant K-RASG12V mutant, favouring its GDP-bound state. In mouse models of gastric and intestinal cancer, a cell-permeable MTMR7-CC mimicry peptide decreased tumour growth, Ki67 proliferation index and ERK1/2 nuclear positivity. Thus, MTMR7 mimicry peptide(s) could provide a novel strategy for targeting mutant K-RAS in cancers.


Subject(s)
Neoplasms , Protein Tyrosine Phosphatases, Non-Receptor , Animals , Humans , Mice , Peptides , Phosphatidylinositol 3-Kinases/metabolism , Protein Tyrosine Phosphatases, Non-Receptor/genetics , Protein Tyrosine Phosphatases, Non-Receptor/metabolism , Signal Transduction
9.
Int Immunopharmacol ; 129: 111644, 2024 Mar 10.
Article in English | MEDLINE | ID: mdl-38330797

ABSTRACT

Residing obligatorily as amastigotes within the mammalian macrophages, the parasite Leishmania donovani inflicts the potentially fatal, globally re-emerging disease visceral leishmaniasis (VL) by altering intracellular signaling through kinases and phosphatases. Because the phosphatases that modulate the VL outcome in humans remained unknown, we screened a human phosphatase siRNA-library for anti-leishmanial functions in THP-1, a human macrophage-like cell line. Of the 251 phosphatases, the screen identified the Ca++-activated K+-channel-associated phosphatase myotubularin-related protein-6 (MTMR6) as the only phosphatase whose silencing reduced parasite load and IL-10 production in human macrophages. Virulent, but not avirulent, L. donovani infection increased MTMR6 expression in macrophages. As virulent L. donovani parasites expressed higher lipophosphoglycan, a TLR2-ligand, we tested the effect of TLR2 stimulation or blockade on MTMR6 expression. TLR1/TLR2-ligand Pam3CSK4 enhanced, but TLR2 blockade reduced, MTMR6 expression. L. donovani infection of macrophages ex vivo increased, but miltefosine treatment reduced, MTMR6 expression. Corroboratively, compared to endemic controls, untreated VL patients had higher, but miltefosine-treated VL patients had reduced, MTMR6 expression. The phosphatase siRNA-library screening thus identified MTMR6 as the first TLR2-modulated ion channel-associated phosphatase with significant implications in VL patients and anti-leishmanial functions.


Subject(s)
Leishmania donovani , Leishmaniasis, Visceral , Phosphorylcholine , Animals , Humans , Ion Channels , Leishmaniasis, Visceral/parasitology , Ligands , Mammals , Phosphorylcholine/analogs & derivatives , Protein Tyrosine Phosphatases, Non-Receptor , RNA, Small Interfering/genetics , Toll-Like Receptor 2
10.
Epilepsy Res ; 200: 107317, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38341935

ABSTRACT

Lafora disease is a rare and fatal form of progressive myoclonic epilepsy with onset during early adolescence. The disease is caused by mutations in EPM2A, encoding laforin, or EPM2B, encoding malin. Both proteins have functions that affect glycogen metabolism, including glycogen dephosphorylation by laforin and ubiquitination of enzymes involved in glycogen metabolism by malin. Lack of function of laforin or malin results in the accumulation of polyglucosan that forms Lafora bodies in the central nervous system and other tissues. Enzyme replacement therapy through intravenous administration of alglucosidase alfa (Myozyme®) has shown beneficial effects removing polyglucosan aggregates in Pompe disease. We evaluated the effectiveness of intracerebroventricular administration of alglucosidase alfa in the Epm2a-/- knock-out and Epm2aR240X knock-in mouse models of Lafora disease. Seven days after a single intracerebroventricular injection of alglucosidase alfa in 12-month-old Epm2a-/- and Epm2aR240X mice, the number of Lafora bodies was not reduced. Additionally, a prolonged infusion of alglucosidase alfa for 2 or 4 weeks in 6- and 9-month-old Epm2a-/- mice did not result in a reduction in the number of LBs or the amount of glycogen in the brain. These findings hold particular significance in guiding a rational approach to the utilization of novel therapies in Lafora disease.


Subject(s)
Lafora Disease , alpha-Glucosidases , Mice , Animals , Lafora Disease/drug therapy , Lafora Disease/genetics , Mice, Knockout , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Glycogen/metabolism , Protein Tyrosine Phosphatases, Non-Receptor/genetics
11.
J Biosci ; 492024.
Article in English | MEDLINE | ID: mdl-38287677

ABSTRACT

Lafora disease (LD) is a life-threatening autosomal recessive and progressive neurodegenerative disorder that primarily affects adolescents, resulting in mortality within a decade of onset. The symptoms of LD include epileptic seizures, ataxia, dementia, and psychosis. The underlying pathology involves the presence of abnormal glycogen inclusions in neurons and other tissues, which may contribute to neurodegeneration. LD is caused by loss-of-function mutations in either the EPM2A gene or the NHLRC1 gene. These two genes, respectively, code for laforin phosphatase and malin ubiquitin ligase, and are thought to function, as a functional complex, in diverse cellular pathways. One of the major pathways affected in LD is glycogen metabolism; defects here lead to abnormally higher levels of glycogen and its hyperphosphorylation and aggregation, resulting in the formation of Lafora inclusion bodies. Currently, there is no effective therapy for LD. Studies, particularly from animal models, provide distinct insights into the fundamental mechanisms of diseases and potential avenues for therapeutic interventions. The purpose of this review is to present a comprehensive overview of our current knowledge regarding the disease, its genetics, the animal models that have been developed, and the therapeutic strategies that are being developed based on an understanding of the disease mechanism.


Subject(s)
Lafora Disease , Animals , Lafora Disease/diagnosis , Lafora Disease/genetics , Lafora Disease/therapy , Protein Tyrosine Phosphatases, Non-Receptor/genetics , Neurons/metabolism , Mutation , Glycogen/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism
12.
Proc Natl Acad Sci U S A ; 121(5): e2319475121, 2024 Jan 30.
Article in English | MEDLINE | ID: mdl-38252824

ABSTRACT

miR-137 is a highly conserved brain-enriched microRNA (miRNA) that has been associated with neuronal function and proliferation. Here, we show that Drosophila miR-137 null mutants display increased body weight with enhanced triglyceride content and decreased locomotor activity. In addition, when challenged by nutrient deprivation, miR-137 mutants exhibit reduced motivation to feed and prolonged survival. We show through genetic epistasis and rescue experiments that this starvation resistance is due to a disruption in insulin signaling. Our studies further show that miR-137 null mutants exhibit a drastic reduction in levels of the phosphorylated/activated insulin receptor, InR (InR-P). We investigated if this is due to the predicted miR-137 target, Protein Tyrosine Phosphatase 61F (PTP61F), ortholog of mammalian TC-PTP/PTP1B, which are known to dephosphorylate InR-P. Indeed, levels of an endogenously tagged GFP-PTP61F are significantly elevated in miR-137 null mutants, and we show that overexpression of PTP61F alone is sufficient to mimic many of the metabolic phenotypes of miR-137 mutants. Finally, we knocked-down elevated levels of PTP61F in the miR-137 null mutant background and show that this rescues levels of InR-P, restores normal body weight and triglyceride content, starvation sensitivity, as well as attenuates locomotor and starvation-induced feeding defects. Our study supports a model in which miR-137 is critical for dampening levels of PTP61F, thereby maintaining normal insulin signaling and energy homeostasis.


Subject(s)
Drosophila Proteins , Insulin , MicroRNAs , Protein Tyrosine Phosphatases, Non-Receptor , Signal Transduction , Animals , Drosophila , Homeostasis , Insulin/metabolism , Mammals , MicroRNAs/metabolism , Phosphoric Monoester Hydrolases , Triglycerides/metabolism , Protein Tyrosine Phosphatases, Non-Receptor/metabolism , Drosophila Proteins/metabolism
13.
Int Immunopharmacol ; 129: 111589, 2024 Mar 10.
Article in English | MEDLINE | ID: mdl-38295542

ABSTRACT

The protozoan parasite Leishmania donovani resides within mammalian macrophages and alters its antigen-presenting functions to negatively regulate host-protective T cell responses. This negative regulation of human T cell responses in vitro is attributed to myotubularin-related protein-6 (MTMR6), an ion channel-associated phosphatase. As mouse and human MTMR6 share homology, we studied whether MTMR6 silencing by lentivirally expressed MTMR6shRNA (Lv-MTMR6shRNA) reduced Leishmania growth in macrophages and whether MTMR6 silencing in Leishmania-susceptible BALB/c mice reduced the infection and reinstated host-protective T cell functions. MTMR6 silencing reduced amastigote count and IL-10 production, increased IL-12 expression and, induced IFN-γ-secreting T cells with anti-leishmanial activity in macrophage-T cell co-cultures. Lv-MTMR6shRNA reduced the infection, accompanied by increased IFN-γ expression, in susceptible BALB/c mice. Delays in Lv-MTMR6shRNA treatment by 7 days post-infection significantly reduced the infection suggesting MTMR6 as a plausible therapeutic target. Priming of BALB/c mice with avirulent parasites and Lv-MTMR6shRNA reduced parasite burden in challenge infection. These results indicate that MTMR6 is the first receptor-regulated ion channel-associated phosphatase regulating anti-leishmanial immune responses.


Subject(s)
Leishmania donovani , Leishmaniasis, Visceral , Leishmaniasis , Mice , Humans , Animals , Protein Tyrosine Phosphatases, Non-Receptor/genetics , Mice, Inbred BALB C , Ion Channels , Mammals
14.
Mod Pathol ; 37(2): 100388, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37995913

ABSTRACT

Cemento-ossifying fibroma (COF) of the jaws is currently classified as a benign mesenchymal odontogenic tumor, and only targeted approaches have been used to assess its genetic alterations. A minimal proportion of COFs harbor CDC73 somatic mutations, and copy number alterations (CNAs) involving chromosomes 7 and 12 have recently been reported in a small proportion of cases. However, the genetic background of COFs remains obscure. We used a combination of whole-exome sequencing and RNA sequencing to assess somatic mutations, fusion transcripts, and CNAs in a cohort of 12 freshly collected COFs. No recurrent fusions have been identified among the 5 cases successfully analyzed by RNA sequencing, with in-frame fusions being detected in 2 cases (MARS1::GOLT1B and PARG::BMS1 in one case and NCLN::FZR1 and NFIC::SAMD1 in the other case) and no candidate fusions identified for the remaining 3 cases. No recurrent pathogenic mutations were detected in the 11 cases that had undergone whole-exome sequencing. A KRAS p.L19F missense variant was detected in one case, and 2 CDC73 deletions were detected in another case. The other variants were of uncertain significance and included variants in PC, ACTB, DOK6, HACE1, and COL1A2 and previously unreported variants in PTPN14, ATP5F1C, APOBEC1, HDAC5, ATF7IP, PARP2, and ACTR3B. The affected genes do not clearly converge on any signaling pathway. CNAs were detected in 5/11 cases (45%), with copy gains involving chromosome 12 occurring in 3/11 cases (27%). In conclusion, no recurrent fusions or pathogenic variants have been detected in the present COF cohort, with copy gains involving chromosome 12 occurring in 27% of cases.


Subject(s)
Cementoma , Fibroma, Ossifying , Odontogenic Tumors , Humans , Cementoma/pathology , Fibroma, Ossifying/genetics , Odontogenic Tumors/pathology , Genomics , Protein Tyrosine Phosphatases, Non-Receptor , Adaptor Proteins, Signal Transducing , Ubiquitin-Protein Ligases
15.
Med Sci (Paris) ; 39 Hors série n° 1: 32-36, 2023 Nov.
Article in French | MEDLINE | ID: mdl-37975768

ABSTRACT

Myotubular myopathy is a rare disease of genetic origin characterized by significant muscle weakness leading to respiratory disorders and for which no treatment exists today. In this paper, we show that inhibition of the activity of the enzyme PI3KC2ß prevents the development of this myopathy in a mouse model of the disease, thus identifying a therapeutic target to treat myotubular myopathy in humans.


Title: Une cible thérapeutique prometteuse dans la myopathie myotubulaire. Abstract: La myopathie myotubulaire est une maladie rare d'origine génétique caractérisée par une importante faiblesse musculaire entraînant des troubles respiratoires et pour laquelle aucun traitement n'existe aujourd'hui. Dans cet article, nous montrons que l'inhibition de l'activité de l'enzyme PI3KC2ß prévient le développement de cette myopathie dans un modèle murin de la maladie, identifiant ainsi une cible thérapeutique pour traiter la myopathie myotubulaire chez l'homme.


Subject(s)
Myopathies, Structural, Congenital , Animals , Mice , Disease Models, Animal , Myopathies, Structural, Congenital/genetics , Myopathies, Structural, Congenital/therapy , Protein Tyrosine Phosphatases, Non-Receptor/genetics
16.
Mol Biol Rep ; 50(12): 10073-10081, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37910386

ABSTRACT

BACKGROUND: Highly upregulated in liver cancer (HULC) is one of the LncRNAs that was documented to enhance cancer progression, and its downregulation is associated with cell cycle arrest and apoptosis. Myotubularin-related protein 3 (MTMR3) is required for autophagy, and many studies consider MTMR3 to be a negative regulator of autophagy processes. However, nothing is understood about how they regulate breast cancer. MATERIAL AND METHODS: This case-control study included 245 patients (Group A: 85 early BC Group B: 40 metastatic BC cases, Group C: 40 fibroadenoma cases; and Group D: 80 age matched healthy control subjects. TaqMan Real-time PCR was used to analyse rs7158663 and rs12537. MTMR3 and HULC gene expression levels were measured using RT-PCR. RESULT: Breast cancer patients exhibited elevated serum MTMR3 and HULC compared to fibroadenomas and control cases. The MTMR3 rs12537 "T/T" genotype was highly expressed in cases of breast cancer (early and metastatic) compared to controls (risk genotype). On the other hand, the HULC rs7158663 genotypes were not statistically associated with breast cancer. However, when compared to the control, the C/C genotype of the HULC gene is higher in the case.MTMR3 gene expression was higher in the T/T genotype compared to both the C/C and C/T genotypes, while HULC gene expression was lower in the A/C genotype compared to both the A/A and C/C genotypes. Positive correlation between MTMR3 and HULC. MTMR3 and ALT, as well as HULC and alkaline phosphatase, both showed a statistically significant positive correlation. CONCLUSION: Our findings reveal that MTMR3 and HULC serum expression and their SNPs (HULC rs7763881, MTMR3 rs12537) are associated with a higher risk for the development of breast cancer in the Egyptian population.


Subject(s)
Breast Neoplasms , Liver Neoplasms , RNA, Long Noncoding , Female , Humans , Breast Neoplasms/genetics , Case-Control Studies , Egypt , Genotype , Liver Neoplasms/genetics , Protein Tyrosine Phosphatases, Non-Receptor/genetics , RNA, Long Noncoding/genetics
17.
Sci Rep ; 13(1): 18701, 2023 10 31.
Article in English | MEDLINE | ID: mdl-37907649

ABSTRACT

Abnormal expression of myotubularin-related protein 2 (MTMR2) has been identified in certain types of cancer, leading to varying effects on tumor genesis and progression. However, the various biological significances of MTMR2 in hepatocellular carcinoma (HCC) have not been systematically and comprehensively studied. The aim of this study was to explore the role of MTMR2 in HCC. We obtained the raw data from Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Afterward, we analyzed the data using R and cBioPortal. We investigated the connection between MTMR2 and its expression, prognosis, clinical significance, methylation, genetic alterations, tumor microenvironment (TME), tumor mutation burden (TMB), and drug reactivity in HCC patients. MTMR2 expression levels in HCC cells were validated through western blotting and RT-qPCR. MTMR2 exhibits high levels of expression across a wide range of cancer types, including HCC. MTMR2 is diagnostically valuable in detecting HCC, with its up-regulated expression often being indicative of poor prognosis among HCC patients. The in vitro experiments confirmed elevated MTMR2 expression in HepG2, HUH-7, and MHCC-97H cells. Univariate and multivariate Cox analysis demonstrated that MTMR2 was an independent prognostic factor in HCC patients. The cg20195272 site has the highest degree of methylation in MTMR2, and it is positively correlated with MTMR2 expression. Patients with high levels of methylation at the cg20195272 site show poor prognosis. Analysis of the TME indicates that high expression of MTMR2 is associated with elevated ESTIMATE score and that MTMR2 expression correlates positively with infiltration by resting memory CD4 T cells, activated dendritic cells, as well as several immune checkpoints. There is a negative correlation between MTMR2 expression and TMB, and drug sensitivity analyses have shown that higher MTMR2 expression is associated with lower IC50 values. This study indicates that increased expression of MTMR2 may play a crucial role in the occurrence, progression, diagnosis, prognostic prediction and drug therapy of HCC.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/genetics , Prognosis , Liver Neoplasms/genetics , Blotting, Western , Cell Line , Tumor Microenvironment/genetics , Protein Tyrosine Phosphatases, Non-Receptor
18.
Cell Death Dis ; 14(10): 671, 2023 10 11.
Article in English | MEDLINE | ID: mdl-37821451

ABSTRACT

Aberrant overexpression or activation of EGFR drives the development of non-small cell lung cancer (NSCLC) and acquired resistance to EGFR tyrosine kinase inhibitors (TKIs) by secondary EGFR mutations or c-MET amplification/activation remains as a major hurdle for NSCLC treatment. We previously identified WDR4 as a substrate adaptor of Cullin 4 ubiquitin ligase and an association of WDR4 high expression with poor prognosis of lung cancer. Here, using an unbiased ubiquitylome analysis, we uncover PTPN23, a component of the ESCRT complex, as a substrate of WDR4-based ubiquitin ligase. WDR4-mediated PTPN23 ubiquitination leads to its proteasomal degradation, thereby suppressing lysosome trafficking and degradation of wild type EGFR, EGFR mutant, and c-MET. Through this mechanism, WDR4 sustains EGFR and c-MET signaling to promote NSCLC proliferation, migration, invasion, stemness, and metastasis. Clinically, PTPN23 is downregulated in lung cancer and its low expression correlates with WDR4 high expression and poor prognosis. Targeting WDR4-mediated PTPN23 ubiquitination by a peptide that competes with PTPN23 for binding WDR4 promotes EGFR and c-MET degradation to block the growth and progression of EGFR TKI-resistant NSCLC. These findings identify a central role of WDR4/PTPN23 axis in EGFR and c-MET trafficking and a potential therapeutic target for treating EGFR TKI-resistant NSCLC.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , ErbB Receptors/metabolism , Protein Kinase Inhibitors/pharmacology , Drug Resistance, Neoplasm/genetics , Mutation , Ubiquitination , Ubiquitin/metabolism , Cell Line, Tumor , Ligases/metabolism , Proto-Oncogene Proteins c-met/metabolism , GTP-Binding Proteins/metabolism , Protein Tyrosine Phosphatases, Non-Receptor/metabolism
19.
Eur J Obstet Gynecol Reprod Biol ; 291: 34-38, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37813004

ABSTRACT

Polyhydramnios can be caused by genetic defects at times. However, to establish an accurate diagnosis and provide a precise prenatal consultation in a given case is still a great challenge toward obstetricians. To uncover the genetic cause of polyhydramnios in the two consecutive pregnancies, we performed whole-exome sequencing of DNA for the second suffering fetuses, their parents, and targeted sanger sequencing of other members of this family. We discovered a hemizygous truncating variant in MTM1 gene, c.438_439 del (p. H146Q fs*10) in this Chinese family. In the light of the molecular discoveries, the fetus's clinical phenotype was considered to be a good fit for X-linked myotubular myopathy (XLMTM). There is no related research to the prenatal manifestations of MTM1-related XLMTM among Chinese population, and this is the first one to present. Though the etiology of polyhydramnios is complicated, WES may provide us with a creative avenue in prenatal diagnosis.


Subject(s)
Myopathies, Structural, Congenital , Polyhydramnios , Pregnancy , Female , Humans , Exome Sequencing , Polyhydramnios/diagnostic imaging , Polyhydramnios/genetics , Protein Tyrosine Phosphatases, Non-Receptor/genetics , Mutation , Myopathies, Structural, Congenital/diagnosis , Myopathies, Structural, Congenital/genetics , Myopathies, Structural, Congenital/pathology
20.
Nutr Bull ; 48(4): 559-571, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37905391

ABSTRACT

Childhood dyslipidaemia is associated with the occurrence of cardiovascular diseases in adulthood, so evaluating whether an individual has a genetic predisposition to this pathology is of great importance for early action of prevention and treatment. This study aimed to evaluate the association between the FTO (rs9939609), MC4R (rs17782313) and MTMR9 (rs2293855) polymorphisms, the obesity-related genetic risk score and atherogenic risk in Brazilian children. This is a cross-sectional study conducted in 544 children aged 4-9 years in the city of Viçosa, Minas Gerais state, Brazil. The single nucleotide polymorphisms rs9939609, rs17782313 and rs2293855, were identified by the system TaqMan SNP genotyping and the obesity-related genetic risk score was determined. The lipid profile (serum total cholesterol [TC], high density lipoprotein [HDL] cholesterol, low density lipoprotein [LDL] cholesterol, triglycerides) was analysed and the atherogenic indices (Castelli I and II indices), atherogenic coefficient (AC), lipoprotein combined index (LCI) and plasma atherogenic index (PAI) were calculated. A semi-structured questionnaire was applied, obtaining data on the sociodemographic, economic and lifestyle characteristics of the children. Weight and height measurements were performed in all children, and body composition was evaluated by Dual-Energy X-ray Absorptiometry (DXA). 55.5% of the sample had dyslipidaemia, while 28.5% of the sample had at least one polymorphism and 2.2% had three polymorphisms. Children with the AG/AA genotypes in the rs2293855 polymorphism had lower HDL cholesterol levels and higher TC/HDL cholesterol, LDL/HDL cholesterol ratios and AC. Those with one or more polymorphisms (rs9939609, rs17782313 and rs2293855) in the genetic risk score had lower HDL cholesterol levels and higher TC/HDL cholesterol ratios, AC, LCI and PAI. In conclusion, the risk allele of the rs2293855 polymorphism and a higher obesity-related genetic risk score were positively associated with higher atherogenic risk in Brazilian children.


Subject(s)
Dyslipidemias , Obesity , Child , Humans , Cholesterol, HDL , Genotype , Cross-Sectional Studies , Body Mass Index , Polymorphism, Single Nucleotide/genetics , Cholesterol , Lipoproteins, HDL/genetics , Dyslipidemias/epidemiology , Protein Tyrosine Phosphatases, Non-Receptor/genetics , Alpha-Ketoglutarate-Dependent Dioxygenase FTO/genetics
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