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1.
Nature ; 568(7753): 551-556, 2019 04.
Article in English | MEDLINE | ID: mdl-30971823

ABSTRACT

Synthetic lethality-an interaction between two genetic events through which the co-occurrence of these two genetic events leads to cell death, but each event alone does not-can be exploited for cancer therapeutics1. DNA repair processes represent attractive synthetic lethal targets, because many cancers exhibit an impairment of a DNA repair pathway, which can lead to dependence on specific repair proteins2. The success of poly(ADP-ribose) polymerase 1 (PARP-1) inhibitors in cancers with deficiencies in homologous recombination highlights the potential of this approach3. Hypothesizing that other DNA repair defects would give rise to synthetic lethal relationships, we queried dependencies in cancers with microsatellite instability (MSI), which results from deficient DNA mismatch repair. Here we analysed data from large-scale silencing screens using CRISPR-Cas9-mediated knockout and RNA interference, and found that the RecQ DNA helicase WRN was selectively essential in MSI models in vitro and in vivo, yet dispensable in models of cancers that are microsatellite stable. Depletion of WRN induced double-stranded DNA breaks and promoted apoptosis and cell cycle arrest selectively in MSI models. MSI cancer models required the helicase activity of WRN, but not its exonuclease activity. These findings show that WRN is a synthetic lethal vulnerability and promising drug target for MSI cancers.


Subject(s)
Microsatellite Instability , Microsatellite Repeats/genetics , Neoplasms/genetics , Synthetic Lethal Mutations/genetics , Werner Syndrome Helicase/genetics , Apoptosis/genetics , CRISPR-Cas Systems/genetics , Cell Cycle Checkpoints/genetics , Cell Line, Tumor , DNA Breaks, Double-Stranded , Humans , Models, Genetic , Neoplasms/pathology , RNA Interference , Tumor Suppressor Protein p53/metabolism , Werner Syndrome Helicase/deficiency
2.
Gut ; 73(8): 1280-1291, 2024 07 11.
Article in English | MEDLINE | ID: mdl-38621923

ABSTRACT

OBJECTIVE: Genomic studies of gastric cancer have identified highly recurrent genomic alterations impacting RHO signalling, especially in the diffuse gastric cancer (DGC) histological subtype. Among these alterations are interchromosomal translations leading to the fusion of the adhesion protein CLDN18 and RHO regulator ARHGAP26. It remains unclear how these fusion constructs impact the activity of the RHO pathway and what is their broader impact on gastric cancer development. Herein, we developed a model to allow us to study the function of this fusion protein in the pathogenesis of DGC and to identify potential therapeutic targets for DGC tumours with these alterations. DESIGN: We built a transgenic mouse model with LSL-CLDN18-ARHGAP26 fusion engineered into the Col1A1 locus where its expression can be induced by Cre recombinase. Using organoids generated from this model, we evaluated its oncogenic activity and the biochemical effects of the fusion protein on the RHOA pathway and its downstream cell biological effects in the pathogenesis of DGC. RESULTS: We demonstrated that induction of CLDN18-ARHGAP26 expression in gastric organoids induced the formation of signet ring cells, characteristic features of DGC and was able to cooperatively transform gastric cells when combined with the loss of the tumour suppressor geneTrp53. CLDN18-ARHGAP26 promotes the activation of RHOA and downstream effector signalling. Molecularly, the fusion promotes activation of the focal adhesion kinase (FAK) and induction of the YAP pathway. A combination of FAK and YAP/TEAD inhibition can significantly block tumour growth. CONCLUSION: These results indicate that the CLDN18-ARHGAP26 fusion is a gain-of-function DGC oncogene that leads to activation of RHOA and activation of FAK and YAP signalling. These results argue for further evaluation of emerging FAK and YAP-TEAD inhibitors for these deadly cancers.


Subject(s)
Claudins , GTPase-Activating Proteins , Mice, Transgenic , Signal Transduction , Stomach Neoplasms , Transcription Factors , YAP-Signaling Proteins , rhoA GTP-Binding Protein , Animals , Stomach Neoplasms/genetics , Stomach Neoplasms/pathology , Stomach Neoplasms/metabolism , GTPase-Activating Proteins/genetics , GTPase-Activating Proteins/metabolism , Mice , rhoA GTP-Binding Protein/metabolism , rhoA GTP-Binding Protein/genetics , Claudins/genetics , Claudins/metabolism , YAP-Signaling Proteins/metabolism , YAP-Signaling Proteins/genetics , Transcription Factors/genetics , Transcription Factors/metabolism , Humans , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism , Oncogene Proteins, Fusion/genetics , Oncogene Proteins, Fusion/metabolism , Focal Adhesion Protein-Tyrosine Kinases/metabolism , Focal Adhesion Protein-Tyrosine Kinases/genetics , TEA Domain Transcription Factors , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Disease Models, Animal , Organoids/metabolism , Organoids/pathology
3.
J Cell Sci ; 134(3)2021 02 05.
Article in English | MEDLINE | ID: mdl-33443093

ABSTRACT

Expression of synphilin-1 in neurons induces hyperphagia and obesity in a Drosophila model. However, the molecular pathways underlying synphilin-1-linked obesity remain unclear. Here, Drosophila models and genetic tools were used to study the synphilin-1-linked pathways in energy balance by combining molecular biology and pharmacological approaches. We found that expression of human synphilin-1 in flies increased AMP-activated kinase (AMPK) phosphorylation at Thr172 compared with that in non-transgenic flies. Knockdown of AMPK reduced AMPK phosphorylation and food intake in non-transgenic flies, and further suppressed synphilin-1-induced AMPK phosphorylation, hyperphagia, fat storage and body weight gain in transgenic flies. Expression of constitutively activated AMPK significantly increased food intake and body weight gain in non-transgenic flies, but it did not alter food intake in the synphilin-1 transgenic flies. In contrast, expression of dominant-negative AMPK reduced food intake in both non-transgenic and synphilin-1 transgenic flies. Treatment with STO-609 also suppressed synphilin-1-induced AMPK phosphorylation, hyperphagia and body weight gain. These results demonstrate that the AMPK signaling pathway plays a critical role in synphilin-1-induced hyperphagia and obesity. These findings provide new insights into the mechanisms of synphilin-1-controlled energy homeostasis.


Subject(s)
AMP-Activated Protein Kinases , Carrier Proteins/genetics , Drosophila , Hyperphagia , Nerve Tissue Proteins/genetics , Obesity , AMP-Activated Protein Kinases/genetics , AMP-Activated Protein Kinases/metabolism , Animals , Animals, Genetically Modified , Drosophila/genetics , Drosophila/metabolism , Humans , Hyperphagia/genetics , Obesity/genetics , Signal Transduction/genetics
4.
J Cell Physiol ; 235(10): 7309-7320, 2020 10.
Article in English | MEDLINE | ID: mdl-32180220

ABSTRACT

Parkinson's disease (PD) is one of the most common movement disorders with loss of dopaminergic neurons and the presence of Lewy bodies in certain brain areas. However, it is not clear how Lewy body (inclusion with protein aggregation) formation occurs. Mutations in leucine-rich repeat kinase 2 (LRRK2) can cause a genetic form of PD and contribute to sporadic PD with the typical Lewy body pathology. Here, we used our recently identified LRRK2 GTP-binding inhibitors as pharmacological probes to study the LRRK2-linked ubiquitination and protein aggregation. Pharmacological inhibition of GTP-binding by GTP-binding inhibitors (68 and Fx2149) increased LRRK2-linked ubiquitination predominantly via K27 linkage. Compound 68- or Fx2149 increased G2019S-LRRK2-linked ubiquitinated aggregates, which occurred through the atypical linkage types K27 and K63. Coexpression of K27R and K63R, which prevented ubiquitination via K27 and K63 linkages, reversed the effects of 68 and Fx2149. Moreover, 68 and Fx2149 also promoted G2019S-LRRK2-linked aggresome (Lewy body-like inclusion) formation via K27 and K63 linkages. These findings demonstrate that LRRK2 GTP-binding activity is critical in LRRK2-linked ubiquitination and aggregation formation. These studies provide novel insight into the LRRK2-linked Lewy body-like inclusion formation underlying PD pathogenesis.


Subject(s)
Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/metabolism , Lewy Bodies/metabolism , Animals , Brain/drug effects , Brain/metabolism , Brain/pathology , Guanosine Triphosphate/metabolism , HEK293 Cells , Humans , Inclusion Bodies/metabolism , Inclusion Bodies/pathology , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/chemistry , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/genetics , Lewy Bodies/pathology , Mice , Mice, Inbred C57BL , Mutant Proteins/chemistry , Mutant Proteins/genetics , Mutant Proteins/metabolism , Mutation , Parkinson Disease/genetics , Parkinson Disease/metabolism , Parkinson Disease/pathology , Protein Aggregation, Pathological/genetics , Protein Aggregation, Pathological/metabolism , Protein Aggregation, Pathological/pathology , Protein Binding , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Ubiquitination
5.
Int J Mol Sci ; 21(12)2020 Jun 18.
Article in English | MEDLINE | ID: mdl-32570982

ABSTRACT

A role for the cytoplasmic protein synphilin-1 in regulating energy balance has been demonstrated recently. Expression of synphilin-1 increases ATP levels in cultured cells. However, the mechanism by which synphilin-1 alters cellular energy status is unknown. Here, we used cell models and biochemical approaches to investigate the cellular functions of synphilin-1 on the AMP-activated protein kinase (AMPK) signaling pathway, which may affect energy balance. Overexpression of synphilin-1 increased AMPK phosphorylation (activation). Moreover, synphilin-1 interacted with AMPK by co-immunoprecipitation and GST (glutathione S-transferase) pull-down assays. Knockdown of synphilin-1 reduced AMPK phosphorylation. Overexpression of synphilin-1 also altered AMPK downstream signaling, i.e., a decrease in acetyl CoA carboxylase (ACC) phosphorylation, and an increase in p70S6K phosphorylation. Treatment of compound C (an AMPK inhibitor) reduced synphilin-1 binding with AMPK. In addition, compound C diminished synphilin-1-induced AMPK phosphorylation, and the increase in cellular ATP (adenosine triphosphate) levels. Our results demonstrated that synphilin-1 couples with AMPK, and they exert mutual effects on each other to regulate cellular energy status. These findings not only identify novel cellular actions of synphilin-1, but also provide new insights into the roles of synphilin-1 in regulating energy currency, ATP.


Subject(s)
AMP-Activated Protein Kinases/metabolism , Adenosine Triphosphate/metabolism , Carrier Proteins/metabolism , Nerve Tissue Proteins/metabolism , Acetyl-CoA Carboxylase/metabolism , HEK293 Cells , Humans , Phosphorylation , Protein Binding , Pyrazoles/pharmacology , Pyrimidines/pharmacology , Signal Transduction/drug effects
6.
Hum Mol Genet ; 25(4): 672-80, 2016 Feb 15.
Article in English | MEDLINE | ID: mdl-26744328

ABSTRACT

Mutations in leucine-rich repeat kinase 2 (LRRK2) cause autosomal-dominant Parkinsonism with pleomorphic pathology including deposits of aggregated protein and neuronal degeneration. The pathogenesis of LRRK2-linked Parkinson's disease (PD) is not fully understood. Here, using co-immunoprecipitation, we found that LRRK2 interacted with synphilin-1 (SP1), a cytoplasmic protein that interacts with α-synuclein and has implications in PD pathogenesis. LRRK2 interacted with the N-terminus of SP1 whereas SP1 predominantly interacted with the C-terminus of LRRK2, including kinase domain. Co-expression of SP1 with LRRK2 increased LRRK2-induced cytoplasmic aggregation in cultured cells. Moreover, SP1 also attenuated mutant LRRK2-induced toxicity and reduced LRRK2 kinase activity in cultured cells. Knockdown of SP1 by siRNA enhanced LRRK2 neuronal toxicity. In vivo Drosophila studies, co-expression of SP1 and mutant G2019S-LRRK2 in double transgenic Drosophila increased survival and improved locomotor activity. Expression of SP1 protects against G2019S-LRRK2-induced dopamine neuron loss and reduced LRRK2 phosphorylation in double transgenic fly brains. Our findings demonstrate that SP1 attenuates mutant LRRK2-induced PD-like phenotypes and plays a neural protective role.


Subject(s)
Carrier Proteins/metabolism , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/metabolism , Nerve Tissue Proteins/metabolism , Parkinson Disease/metabolism , Animals , Animals, Genetically Modified , Carrier Proteins/genetics , Cell Line, Tumor , Disease Models, Animal , Dopamine/metabolism , Drosophila , Gene Knockdown Techniques , HEK293 Cells , Humans , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/genetics , Mice , Mutation , Nerve Degeneration/genetics , Nerve Tissue Proteins/genetics , Neurons/enzymology , Neurons/metabolism , Neurons/pathology , Parkinson Disease/enzymology , Parkinson Disease/genetics , Parkinson Disease/pathology , Phosphorylation , Protein Interaction Domains and Motifs , alpha-Synuclein/genetics , alpha-Synuclein/metabolism
7.
Biochem Cell Biol ; 96(4): 441-449, 2018 08.
Article in English | MEDLINE | ID: mdl-29268033

ABSTRACT

Although the pathogenesis of Parkinson's disease (PD) remains unclear, mutations in leucine-rich repeat kinase 2 (Lrrk2) are among the major causes of familial PD. Most of these mutations disrupt Lrrk2 kinase and (or) GTPase domain function, resulting in neuronal degeneration. However, the signal pathways underlying Lrrk2-induced neuronal degeneration are not fully understood. There is an expanding body of evidence that suggests a link between Lrrk2 function and MAP kinase (MAPK) cascades. To further investigate this link in vivo, genetic RNAi screens of the MAPK pathways were performed in a Drosophila model to identify genetic modifier(s) that can suppress G2019S-Lrrk2-induced PD-like phenotypes. The results revealed that the knockdown of hemipterous (hep, or JNKK) increased fly survival time, improved locomotor function, and reduced loss of dopaminergic neurons in G2019S-Lrrk2 transgenic flies. Expression of the dominant-negative allele of JNK (JNK-DN), a kinase that is downstream of hep in G2019S-Lrrk2 transgenic flies, elicited a similar effect. Moreover, treatment with the JNK inhibitor SP600125 partially reversed the G2019S-Lrrk2-induced loss of dopaminergic neurons. These results indicate that the hep pathway plays an important role in Lrrk2-linked Parkinsonism in flies. These studies provide new insights into the molecular mechanisms underlying Lrrk2-linked PD pathogenesis and aid in identifying potential therapeutic targets.


Subject(s)
Dopaminergic Neurons/metabolism , Drosophila Proteins/genetics , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/genetics , Neurodegenerative Diseases/genetics , Protein Serine-Threonine Kinases/metabolism , Animals , Animals, Genetically Modified , Disease Models, Animal , Drosophila melanogaster , Mutation/genetics , Signal Transduction/physiology
8.
Hum Mol Genet ; 23(23): 6212-22, 2014 Dec 01.
Article in English | MEDLINE | ID: mdl-24993787

ABSTRACT

Mutations in the leucine-rich repeat kinase-2 (LRRK2) gene cause autosomal-dominant Parkinson's disease (PD) and contribute to sporadic PD. LRRK2 contains Guanosine-5'-triphosphate (GTP) binding, GTPase and kinase activities that have been implicated in the neuronal degeneration of PD pathogenesis, making LRRK2, a potential drug target. To date, there is no disease-modifying drug to slow the neuronal degeneration of PD and no published LRRK2 GTP domain inhibitor. Here, the biological functions of two novel GTP-binding inhibitors of LRRK2 were examined in PD cell and mouse models. Through a combination of computer-aided drug design (CADD) and LRRK2 bio-functional screens, two novel compounds, 68: and 70: , were shown to reduce LRRK2 GTP binding and to inhibit LRRK2 kinase activity in vitro and in cultured cell assays. Moreover, these two compounds attenuated neuronal degeneration in human SH-SY5Y neuroblastoma cells and mouse primary neurons expressing mutant LRRK2 variants. Although both compounds inhibited LRRK2 kinase activity and reduced neuronal degeneration, solubility problems with 70: prevented further testing in mice. Thus, only 68: was tested in a LRRK2-based lipopolysaccharide (LPS)-induced pre-inflammatory mouse model. 68: reduced LRRK2 GTP-binding activity and kinase activity in brains of LRRK2 transgenic mice after intraperitoneal injection. Moreover, LPS induced LRRK2 upregulation and microglia activation in mouse brains. These findings suggest that disruption of GTP binding to LRRK2 represents a potential novel therapeutic approach for PD intervention and that these novel GTP-binding inhibitors provide both tools and lead compounds for future drug development.


Subject(s)
Guanosine Triphosphate/metabolism , Neurons/drug effects , Parkinson Disease/pathology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Sulfones/pharmacology , Thiazoles/pharmacology , Animals , Brain/drug effects , Brain/metabolism , Brain/pathology , Cell Survival/drug effects , Cells, Cultured , Disease Models, Animal , Humans , Inflammation/metabolism , Inflammation/pathology , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2 , Lipopolysaccharides/pharmacology , Mice , Mice, Transgenic , Microglia/drug effects , Microglia/metabolism , Microglia/pathology , Mutation , Neurons/metabolism , Neurons/pathology , Parkinson Disease/drug therapy , Parkinson Disease/enzymology , Phosphorylation , Protein Binding , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Sulfones/therapeutic use , Thiazoles/therapeutic use
9.
Biomolecules ; 14(9)2024 Sep 22.
Article in English | MEDLINE | ID: mdl-39334961

ABSTRACT

Barrett's esophagus (BE) is a common precancerous lesion that can progress to esophageal adenocarcinoma (EAC). There are significant alterations in the esophageal microbiome in the progression from healthy esophagus to BE to EAC, including an increased abundance of a variety of lactate-producing bacteria and an increase of lactate in the tumor microenvironment, as predicted by metabolic modeling. The role of bacterial lactate in EAC is unknown. Here, we utilize patient-derived organoid (PDO) models of EAC and demonstrate that lactate inhibits the growth and proliferation of EAC PDOs through alterations in the tumor NADH/NAD+ redox state. Further RNA sequencing of EAC PDOs identifies ID1 and RSAD2 as potential regulatory molecules crucial in mediating lactate's ability to suppress glycolysis and proliferation. Gene ontology analysis also identifies the activation of inflammatory and immunological pathways in addition to alterations in the metabolic pathways in EAC PDOs exposed to lactate, suggesting a multi-faceted role for lactate in the pathogenesis of EAC.


Subject(s)
Adenocarcinoma , Cell Proliferation , Esophageal Neoplasms , Lactic Acid , NAD , Organoids , Oxidation-Reduction , Esophageal Neoplasms/metabolism , Esophageal Neoplasms/pathology , Humans , Adenocarcinoma/metabolism , Adenocarcinoma/pathology , Organoids/metabolism , Organoids/drug effects , NAD/metabolism , Lactic Acid/metabolism , Cell Proliferation/drug effects , Glycolysis/drug effects , Barrett Esophagus/metabolism , Barrett Esophagus/pathology , Tumor Microenvironment
10.
Protein Pept Lett ; 31(3): 229-235, 2024.
Article in English | MEDLINE | ID: mdl-38288820

ABSTRACT

OBJECTIVES: In this study, we employed an in vitro culturing technique to investigate the impact of p53 on the modulation of growth-associated protein-43 (GAP-43) within the primary cortical neurons of rat specimens. METHODS: (1) Within the first 24 hours after birth, the bilateral cortex was extracted from newborn Wistar rats and primary cortical neurons were cultured and identified. (2) The changes in the mRNA and protein expressions of GAP-43 induced by p53 in rat primary cortical neurons cultured in vitro were identified utilizing real-time polymerase chain reaction and western blot techniques. RESULTS: (1) Lentiviral transfection of p53 within primary cortical neurons of rats elicited elevated levels of both mRNA and protein expressions of GAP-43, consequently culminating in a noteworthy augmentation of p53 expression. (2) The introduction of a p53 inhibitor in rat primary cortical neurons resulted in a reduction in both mRNA and protein expressions of GAP-43. CONCLUSION: Within primary rat cortical neurons, p53 has the potential to prompt an augmentation in both the transcriptional and protein expression levels of the GAP-43 protein.


Subject(s)
Cerebral Cortex , GAP-43 Protein , Neurons , Rats, Wistar , Tumor Suppressor Protein p53 , Up-Regulation , Animals , Rats , Cells, Cultured , Cerebral Cortex/metabolism , Cerebral Cortex/cytology , GAP-43 Protein/metabolism , GAP-43 Protein/genetics , Neurons/metabolism , Neurons/cytology , RNA, Messenger/genetics , RNA, Messenger/metabolism , Tumor Suppressor Protein p53/metabolism , Tumor Suppressor Protein p53/genetics
11.
bioRxiv ; 2024 Oct 09.
Article in English | MEDLINE | ID: mdl-39416037

ABSTRACT

The human esophagus, derived from the anterior foregut endoderm, requires proper dorsal-ventral patterning for development. The transcription factor SOX2, crucial in this process, when dysregulated, leads to congenital esophageal abnormalities. EPHA2, a receptor tyrosine kinase, is vital in various developmental processes and cancer models, where it activates SOX2. This study demonstrates that EPHA2 regulates SOX2 expression during esophageal development using human iPSCs and iPSC-derived human esophageal organoids (HEO). Inhibition of EPHA2 decreased iPSC-derived HEO formation and SOX2 expression. These findings provide evidence of EPHA2 as being a key regulator of SOX2 signaling in early esophageal development. Highlights: SOX2 is crucial for proper esophageal development.EPHA2 is a receptor tyrosine kinase involved in various developmental processes.EPHA2 activates SOX2.Inhibition of EPHA2 decreased SOX2 expression and human esophageal organoid formation.

12.
JCI Insight ; 8(3)2023 02 08.
Article in English | MEDLINE | ID: mdl-36752207

ABSTRACT

Gastroesophageal adenocarcinomas (GEAs) harbor recurrent amplification of KRAS, leading to marked overexpression of WT KRAS protein. We previously demonstrated that SHP2 phosphatase, which acts to promote KRAS and downstream MAPK pathway activation, is a target in these tumors when combined with MEK inhibition. We hypothesized that SHP2 inhibitors may serve as a foundation for developing novel combination inhibitor strategies for therapy of KRAS-amplified GEA, including with targets outside the MAPK pathway. Here, we explore potential targets to effectively augment the efficacy of SHP2 inhibition, starting with genome-wide CRISPR screens in KRAS-amplified GEA cell lines with and without SHP2 inhibition. We identify candidate targets within the MAPK pathway and among upstream RTKs that may enhance SHP2 efficacy in KRAS-amplified GEA. Additional in vitro and in vivo experiments demonstrated the potent cytotoxicity of pan-ERBB kinase inhibitions in vitro and in vivo. Furthermore, beyond targets within the MAPK pathway, we demonstrate that inhibition of CDK4/6 combines potently with SHP2 inhibition in KRAS-amplified GEA, with greater efficacy of this combination in KRAS-amplified, compared with KRAS-mutant, tumors. These results suggest therapeutic combinations for clinical study in KRAS-amplified GEAs.


Subject(s)
Neoplasms , Proto-Oncogene Proteins p21(ras) , Proto-Oncogene Proteins p21(ras)/metabolism , Protein Tyrosine Phosphatase, Non-Receptor Type 11/genetics , Mutation , Cell Line, Tumor
13.
Clin Cancer Res ; 29(1): 197-208, 2023 01 04.
Article in English | MEDLINE | ID: mdl-36278961

ABSTRACT

PURPOSE: Diffuse gastric cancer (DGC) is an aggressive and frequently lethal subtype of gastric cancer. Because DGC often lacks genomic aberrations that indicate clear candidate therapeutic targets, it has been challenging to develop targeted therapies for this gastric cancer subtype. Our previous study highlighted the contribution of focal adhesion kinase (FAK) in the tumorigenesis of DGC and the potential efficacy of small-molecule FAK inhibitors. However, drug resistance to monotherapy often hinders the efficacy of treatment. EXPERIMENTAL DESIGN: We generated a genome-scale library of open reading frames (ORF) in the DGC model of Cdh1-/-RHOAY42C/+ organoids to identify candidate mechanisms of resistance to FAK inhibition. Compensatory activated pathways were also detected following treatment with FAK inhibitors. Candidates were investigated by cotargeting in vitro and in vivo experiments using DGC. RESULTS: We found that cyclin-dependent kinase 6 (CDK6) promoted FAK inhibitor resistance in ORF screen. In addition, FAK inhibitor treatment in DGC models led to compensatory MAPK pathway activation. Small-molecule CDK4/6 inhibitors or MAPK inhibitors effectively enhanced FAK inhibitor efficacy in vitro and in vivo. CONCLUSIONS: Our data suggest that FAK inhibitors combined with MAPK inhibitors or CDK4/6 inhibitors warrant further testing in clinical trials for DGC.


Subject(s)
Stomach Neoplasms , Humans , Focal Adhesion Protein-Tyrosine Kinases/metabolism , Stomach Neoplasms/drug therapy , Stomach Neoplasms/genetics , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use
14.
Neurobiol Dis ; 47(3): 385-92, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22668778

ABSTRACT

Parkinson's disease (PD) is a neurodegenerative disorder characterized by selective loss of dopaminergic neurons and the presence of Lewy bodies. The pathogenesis of PD is believed to involve both genetic susceptibility and environmental factors. Mutations in Leucine-rich repeat kinase 2 (LRRK2) cause genetic forms of PD, and the LRRK2 locus contributes to sporadic PD. Environmental toxins are believed to act in part by causing oxidative stress. Here we employed cell and Drosophila models to investigate the interaction between LRRK2 genetic mutations and oxidative stress. We found that H(2)O(2) increased LRRK2 kinase activity and enhanced LRRK2 cell toxicity in cultured cells and mouse primary cortical neurons. Furthermore, a sub-toxic dose of H(2)O(2) significantly shortened the survival of LRRK2 transgenic flies and augmented LRRK2-induced locomotor defects and dopamine neuron loss. Treatment with a LRRK2 kinase inhibitor (GW5074) or an anti-oxidant (curcumin) significantly suppressed these PD-like phenotypes in flies. Moreover, curcumin significantly reduced LRRK2 kinase activity and the levels of oxidized proteins, and thus acted as not only an antioxidant but also a LRRK2 kinase inhibitor. These results indicate that LRRK2 genetic alterations can interact with oxidative stress, converging on a pathogenic pathway that may be related to PD. These studies also identified curcumin as a LRRK2 kinase inhibitor that may be a useful candidate for LRRK2-linked PD intervention.


Subject(s)
Curcumin/pharmacology , Drosophila Proteins/genetics , Enzyme Inhibitors/pharmacology , Mutation/genetics , Protein Serine-Threonine Kinases/drug effects , Protein Serine-Threonine Kinases/genetics , Analysis of Variance , Animals , Animals, Genetically Modified , Cell Survival/drug effects , Cell Survival/genetics , Cerebral Cortex/cytology , Dopamine/metabolism , Drosophila , Drosophila Proteins/metabolism , Drug Interactions , Gene Expression Regulation/drug effects , Gene Expression Regulation/genetics , Green Fluorescent Proteins/metabolism , Humans , Hydrogen Peroxide/pharmacology , Immunoprecipitation , Indoles/pharmacology , Mice , Models, Animal , Motor Activity/drug effects , Motor Activity/genetics , Neurons/drug effects , Neurons/physiology , Oxidants/pharmacology , Oxidation-Reduction/drug effects , Phenols/pharmacology , Phosphorylation/drug effects , Phosphorylation/genetics , Protein Serine-Threonine Kinases/metabolism , Survival Analysis , Transfection
15.
Am J Physiol Gastrointest Liver Physiol ; 302(9): G948-57, 2012 May 01.
Article in English | MEDLINE | ID: mdl-22301113

ABSTRACT

Endothelin-1 (ET-1), a powerful vasoconstrictor peptide, is produced by activated hepatic stellate cells (HSC) and promotes cell proliferation, fibrogenesis, and contraction, the latter of which has been thought to be mechanistically linked to portal hypertension in cirrhosis. Interferon-γ (IFNγ), a Th1 cytokine produced by T cells, inhibits stellate cell proliferation, fibrogenesis, and muscle-specific gene expression. Whether IFNγ-induced inhibitory effects are linked to regulation of ET-1 expression in activated stellate cells remains unknown. Here we examined IFNγ's effects on preproET-1 mRNA expression and the signaling pathways underlying this process. We demonstrated that preproET-1 mRNA expression in HSCs was prominently increased during cell culture-induced activation; IFNγ significantly inhibited both preproET-1 mRNA expression and ET-1 peptide production. Similar results were found in an in vivo model of liver injury and intraperitoneal administration of IFNγ. PreproET-1 promoter analysis revealed that IFNγ-induced inhibition of preproET-1 mRNA expression was closely linked to the AP-1 and Smad3 signaling pathways. Furthermore, IFNγ reduced JNK phosphorylation, which tightly was associated with decreased phosphorylation of downstream factors c-Jun and Smad3 and decreased binding activity of c-Jun and Smad3 in the preprpET-1 promoter. Importantly, IFNγ reduced both c-Jun mRNA and protein levels. Given the important role of ET-1 in wound healing, our results suggest a novel negative signaling network by which IFNγ inhibits preproET-1 expression, highlighting one potential molecular mechanism for IFNγ-induced host immunomodulation of liver fibrogenesis.


Subject(s)
Endothelin-1/metabolism , Interferon-gamma/metabolism , Animals , Base Sequence , Cells, Cultured , Down-Regulation/physiology , Endothelin-1/genetics , Hepatic Stellate Cells , Molecular Sequence Data , Rats , Rats, Sprague-Dawley
16.
J Environ Public Health ; 2022: 8275938, 2022.
Article in English | MEDLINE | ID: mdl-36225754

ABSTRACT

In order to build a harmonious economic society, show the legal function in the society, enable people to live and work in a better environment, and increase people's practicality in the legal society, it needs to be analyzed from the perspective of social psychology. This paper comprehensively analyzes the current public legal knowledge, uses a deep neural network model, and implements the cultivation of public legal awareness. On this basis, it integrates the data and information before and after 2020, uses the method of book case distribution training, constructs a legal framework, relies on the data distribution technology, constructs a web legal awareness training system, and increases the conditions for promoting the cultivation of public legal awareness based on the background operation of the integrated website. It can be seen that in the perspective of social psychology, the importance of the cultivation of public legal awareness can be achieved through new algorithms, so that people can pay attention to the cultivation of legal awareness, which can provide corresponding protection for the operation and maintenance of the legal system.


Subject(s)
Consciousness , Psychology, Social , Humans
17.
Nat Sci Sleep ; 14: 1009-1019, 2022.
Article in English | MEDLINE | ID: mdl-35642211

ABSTRACT

Purpose: Insomnia is a recognized feature of generalized anxiety disorder (GAD). The underlying neural substrate of insomnia in GAD is still unclear. Cortical folding is a reliable index and possibly an endophenotype of psychiatric disease. The aim of this study was to explore whether the aberrant cortical morphology was associated with insomnia in GAD. Patients and Methods: We enrolled 73 patients with GAD and 74 matched healthy controls (HCs) to undergo neuropsychiatric assessment and 3.0 T magnetic resonance imaging scanning. Neuropsychiatric batteries included the 14-item Hamilton Anxiety Rating Scale (HAMA) and the Insomnia Severity Index (ISI). Using FreeSurfer7.1.1, we calculated local gyrification index, cortical thickness and surface area and identified group differences in these parameters. Then, we calculated the functional connectivity of these identified regions and determined functional alterations. The relationship between these neuroimaging indicators and clinical measurement was explored. Results: Compared with HCs, the LGI in the bilateral orbitofrontal cortex (OFC), bilateral insula, left middle frontal gyrus, left temporal pole, and left fusiform area was significantly decreased in GAD. GAD patients had concurrent decreased surface area in the left OFC and thicker right OFC. GAD patients also exhibited increased functional connectivity between the left insula and frontoparietal control network. In addition, a negative relationship was observed between decreased LGI in these limbic regions and ISI score. Conclusion: GAD patients presented aberrant cortical folding in limbic network. Cortical morphology is a potential endophenotype in GAD, corresponding to an insomnia phenotype.

18.
Front Pediatr ; 9: 618059, 2021.
Article in English | MEDLINE | ID: mdl-33643973

ABSTRACT

Objective: The aim of the present study is to explore the clinical and genetic characteristics of 3p deletion syndrome to improve clinicians' understanding of the disease. Methods: The clinical manifestations, process of diagnosis and treatment, and genetic characteristics of an individual case of 3p deletion syndrome were analyzed. CNKI, Wanfang Data, and the Biomedical Literature Database (PubMed) were searched. The search time limit, using "3p deletion syndrome" and "BRPF1" as keywords, was from the creation of the database up to June 2020. Related data were reviewed. Results: The proband was a male child with general developmental and intellectual disabilities, special facial features and congenital heart disease. The child was the parents' first pregnancy and first born. Gene microarray analysis showed a 10.095 Mb deletion in the 3p26.3-p25.3 region, resulting in a heterozygous mutation of the BRPF1 gene; thus, the patient was diagnosed with 3p deletion syndrome. At the time of diagnosis, the child was 1 year of age and was responding to comprehensive rehabilitation training. A total of 29 well-documented cases were found in the literature, of which 19 cases had an onset within 1 year of birth, and mainly manifested with mental and motor development disabilities and abnormal facial features, with different gene deletions, depending on the size and location of the 3p deletion. Conclusion: The genetic test results of the child in this study indicated a heterozygous deletion of the BRPF1 gene on the short arm of chromosome 3, which was a unique feature of this study, since it was rarely mentioned in other reports of 3p deletion syndrome. The clinical phenotype of this syndrome is complex as it can include intellectual and motor development backwardness, low muscle tone, certain abnormal facial features (low hairline, bilateral ptosis, widely spaced eyes, a forward nose, left ear auricle deformity, a high-arched palate, a small jaw), and the deformation of systems such as the gastrointestinal tract and the urinary tract malformation or symptoms of epilepsy. As clinical manifestations can be relatively mild, the syndrome is easy to miss or misdiagnose. Clinical workers need to be aware of this disease when they find that children have special features, such as stunted growth, low muscle tone or ptosis, and it needs to be diagnosed through genetic testing. Most children are able to develop certain social skills after rehabilitation treatment.

19.
Cells ; 10(2)2021 02 23.
Article in English | MEDLINE | ID: mdl-33672296

ABSTRACT

Mutations in the leucine-rich repeat kinase-2 (LRRK2) gene cause autosomal-dominant Parkinson's disease (PD) and contribute to sporadic PD. Common genetic variation in LRRK2 modifies susceptibility to immunological disorders including Crohn's disease and leprosy. Previous studies have reported that LRRK2 is expressed in B lymphocytes and macrophages, suggesting a role for LRRK2 in immunological functions. In this study, we characterized the LRRK2 protein expression and phosphorylation using human lymphoblasts. Lipopolysaccharide (LPS), a proinflammatory agent, induced the increase of LRRK2 expression and kinase activities in human lymphoblasts in a time-dependent manner. Moreover, LPS activated the Toll-like receptor (TLR) signaling pathway, increased TRAF6/LRRK2 interaction, and elevated the phosphorylation levels of MAPK (JNK1/2, p38, and ERK1/2) and IkBα. Treatment with LRRK2 inhibitor 68 reduced LPS-induced TRAF6/LRRK2 interaction and MAPK and IkBα phosphorylation, thereby reducing TNF-α secretion. These results indicate that LRRK2 is actively involved in proinflammatory responses in human lymphoblasts, and inhibition of GTP binding by 68 results in an anti-inflammation effect against proinflammatory stimuli. These findings not only provide novel insights into the mechanisms of LRRK2-linked immune and inflammatory responses in B-cell-like lymphoblasts, but also suggest that 68 may also have potential therapeutic value for LRRK2-linked immunological disorders.


Subject(s)
Guanosine Triphosphate/metabolism , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/metabolism , Lipopolysaccharides/pharmacology , Lymphocytes/metabolism , Signal Transduction , Tumor Necrosis Factor-alpha/metabolism , Enzyme Activation/drug effects , HEK293 Cells , Humans , Lymphocytes/drug effects , MAP Kinase Signaling System/drug effects , Models, Biological , NF-KappaB Inhibitor alpha/metabolism , Phosphorylation/drug effects , Protein Binding/drug effects , TNF Receptor-Associated Factor 6/metabolism
20.
Brain Behav ; 11(8): e2219, 2021 08.
Article in English | MEDLINE | ID: mdl-34292674

ABSTRACT

BACKGROUND: The chromosomal 15q11-q13 regions are structurally complex, and their abnormalities are associated with various neuropsychiatric disorders, including autism spectrum disorder (ASD), epilepsy, Angelman syndrome, and Prader-Willi syndrome. CASE DESCRIPTION: A 6-year-old child was admitted to the hospital as a result of an "epileptic status" showing ASD, intractable epilepsy, and total developmental retardation. Chromosome gene detection showed repetitive variation in the 15q11-q13 regions, and the video electroencephalogram was abnormal. Although children are currently given antiepileptic treatment and rehabilitation training, intermittent seizures can still occur. CONCLUSION: The clinical phenotypes of 15q11-q13 repetitive syndrome are complex, and vary in severity. Children with intractable epilepsy, ASD, and language and motor retardation should be considered to have this syndrome, which requires confirmation by multiplex ligation-dependent probe amplification and gene detection. These approaches can enable early rehabilitation treatment and improve the patients' quality of life.


Subject(s)
Angelman Syndrome , Autism Spectrum Disorder , Prader-Willi Syndrome , Angelman Syndrome/genetics , Child , Humans , Phenotype , Quality of Life
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