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1.
Am J Pathol ; 194(5): 708-720, 2024 May.
Article in English | MEDLINE | ID: mdl-38320628

ABSTRACT

Psoriasis is a chronic inflammatory skin disease characterized by the activation of keratinocytes and the infiltration of immune cells. Overexpression of the transcription factor LIM-domain only protein 4 (LMO4) promoted by IL-23 has critical roles in regulating the proliferation and differentiation of psoriatic keratinocytes. IL-6, an autocrine cytokine in psoriatic epidermis, is a key mediator of IL-23/T helper 17-driven cutaneous inflammation. However, little is known about how IL-6 regulates the up-regulation of LMO4 expression in psoriatic lesions. In this study, human immortalized keratinocyte cells, clinical biopsy specimens, and an animal model of psoriasis induced by imiquimod cream were used to investigate the role of IL-6 in the regulation of keratinocyte proliferation and differentiation. Psoriatic epidermis showed abnormal expression of IL-6 and LMO4. IL-6 up-regulated the expression of LMO4 and promoted keratinocyte proliferation and differentiation. Furthermore, in vitro and in vivo studies showed that IL-6 up-regulates LMO4 expression by activating the mitogen-activated extracellular signal-regulated kinase (MEK)/extracellular signal-regulated kinase (ERK)/NF-κB signaling pathway. These results suggest that IL-6 can activate the NF-κB signaling pathway, up-regulate the expression of LMO4, lead to abnormal proliferation and differentiation of keratinocytes, and promote the occurrence and development of psoriasis.


Subject(s)
Extracellular Signal-Regulated MAP Kinases , Psoriasis , Animals , Humans , Adaptor Proteins, Signal Transducing/metabolism , Extracellular Signal-Regulated MAP Kinases/metabolism , Interleukin-23/adverse effects , Interleukin-23/metabolism , Interleukin-6/metabolism , Keratinocytes/pathology , LIM Domain Proteins/metabolism , Mitogen-Activated Protein Kinase Kinases/metabolism , NF-kappa B/metabolism , Psoriasis/pathology
2.
J Cell Sci ; 135(18)2022 09 15.
Article in English | MEDLINE | ID: mdl-36148798

ABSTRACT

Swift and complete spindle disassembly in late mitosis is essential for cell survival, yet how it happens is largely unknown in mammalian cells. Here we used real-time live cell microscopy and biochemical assays to show that the primordial dwarfism (PD)-related cysteine-rich protein CRIPT dictates the spindle disassembly in a redox-dependent manner in human cells. This previously reported cytoplasmic protein was found to have a confined nuclear localization with a nucleolar concentration during interphase but was distributed to spindles and underwent redox modifications to form disulfide bonds in CXXC pairs during mitosis. Then, it directly interacted with, and might transfer a redox response to, tubulin subunits via a putative redox exchange among cysteine residues to induce microtubule depolymerization. Expression of CRIPT proteins with mutations of these cysteine residues blocked spindle disassembly, generating two cell types with long-lasting metaphase spindles or spindle remnants. Live-cell recordings of a disease-relevant mutant (CRIPTC3Y) revealed that microtubule depolymerization at spindle ends during anaphase and the entire spindle dissolution during telophase might share a common CRIPT-bearing redox-controlled mechanism.


Subject(s)
Spindle Apparatus , Tubulin , Adaptor Proteins, Signal Transducing/metabolism , Anaphase , Animals , Cysteine/metabolism , Disulfides/metabolism , Humans , Mammals/metabolism , Metaphase , Microtubules/metabolism , Mitosis , Oxidation-Reduction , Spindle Apparatus/metabolism , Tubulin/metabolism
5.
Int J Infect Dis ; 99: 84-91, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32758689

ABSTRACT

BACKGROUND: The antiviral effects of Novaferon, a potent antiviral protein drug, on COVID-19 was evaluated in the laboratory, and in a randomized, open-label, parallel-group trial. METHODS: In the laboratory, Novaferon's inhibition of viral replication in cells infected with SARS-CoV-2, and prevention of SARS-CoV-2 entry into healthy cells was determined. Antiviral effects of Novaferon in COVID-19 patients with treatment of Novaferon, Novaferon plus Lopinavir/Ritonavir, or Lopinavir/Ritonavir were evaluated. The primary endpoint was the SARS-CoV-2 clearance rates on day six of treatment, and the secondary endpoint was the time to SARS-CoV-2 clearance. RESULTS: Novaferon inhibited viral replication (EC50=1.02ng/ml), and prevented viral infection (EC50=0.10ng/ml). Results from the 89 enrolled COVID-19 patients showed that both Novaferon and Novaferon plus Lopinavir/Ritonavir groups had significantly higher viral clearance rates on day six than Lopinavir/Ritonavir group (50.0% vs. 24.1%, p=0.0400, and 60.0% vs. 24.1%, p=0.0053). The median time to viral clearance was six days, six days, and nine days for three groups, respectively, a 3-day reduction in both the Novaferon and Novaferon plus Lopinavir/Ritonavir groups compared with the Lopinavir/Ritonavir group. CONCLUSIONS: Novaferon exhibited anti-SARS-CoV-2 effects in vitro and in COVID-19 patients. These data justify further evaluation of Novaferon. TRIAL REGISTRATION NUMBER: Number ChiCTR2000029496 at the Chinese Clinical Trial Registry (http://www.chictr.org.cn/).


Subject(s)
Betacoronavirus/drug effects , Coronavirus Infections/drug therapy , Interferons/therapeutic use , Pneumonia, Viral/drug therapy , Administration, Inhalation , Antiviral Agents/administration & dosage , Antiviral Agents/therapeutic use , COVID-19 , Female , Humans , Interferons/administration & dosage , Male , Pandemics , Recombinant Proteins/administration & dosage , Recombinant Proteins/therapeutic use , SARS-CoV-2 , Virus Replication/drug effects , COVID-19 Drug Treatment
6.
Aging (Albany NY) ; 12(12): 11296-11305, 2020 06 22.
Article in English | MEDLINE | ID: mdl-32575073

ABSTRACT

BACKGROUND: SARS-CoV-2 causes high mortality risk in older patients. This study aims to characterize the clinical features of older and younger SARS-CoV-2 infected patients. RESULTS: A total of 239 patients were divided into the younger group (<60 years; n=181) and the older group (≥60 years; n=58). In both groups, fever and cough were common symptoms. However, dyspnea was more frequent in older patients than younger patients (20.7% versus 9.9%, p=0.032). Compared with younger patients, older patients harbored more severe cases (37.9% versus 17.1%, p=0.001) and comorbidities (58.6% versus 21.0%, p<0.001) such as hypertension and diabetes. The baseline values of eosinophils and C-reactive protein were abnormal in older and younger groups. From baseline to day 14, significant decreases of three biomarkers (C-reactive protein, hemoglobin, albumin) and dramatic increases of three biomarkers (lymphocytes, platelets, blood urea nitrogen) were observed in older patients. CONCLUSION: Older and younger patients exhibited differences in dyspnea, comorbidities, and proportions of severe cases. Moreover, the disease progression of SARS-CoV-2 in older patients is observed with the dynamics of laboratory biomarkers, supporting their potential use in disease monitoring. METHODS: We retrieved clinical symptoms, laboratory findings, comorbidities, and hospitalization information of SARS-CoV-2 cases in Changsha.


Subject(s)
Aging , Betacoronavirus , Coronavirus Infections/pathology , Pneumonia, Viral/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Biomarkers , COVID-19 , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Pandemics , Risk Factors , SARS-CoV-2 , Young Adult
7.
Aging (Albany NY) ; 12(12): 11224-11237, 2020 06 17.
Article in English | MEDLINE | ID: mdl-32554861

ABSTRACT

With the outbreak of coronavirus disease-19 (COVID-19), Changsha faced an increasing burden of treating the Wuhan migrants and their infected patients. This study is a retrospective, single-center case series of the 238 consecutive hospitalized patients with confirmed COVID-19 at the First Hospital of Changsha city, China, from 01/21 to 02/14, 2020; the final date of follow-up was 02/27, 2020. Of 238 patients 43.7% visited Wuhan, 58.4% got in touch with Wuhan people, and 47.5% had contacted with diagnosed patients. 37.8% patients had family members infected. 190 cases had mild / general disease, and 48 cases had severe / critical disease. Compared to mild or general patients, more severe or critical patients visited Wuhan (59.6% vs 40.2%; P=0.02) and contacted with Wuhan people (74.5% vs 55.0%; P=0.02). All patients received antiviral treatment, including Lopinavir / Ritonavir (29.3%), Interferon (14.6%) and their combination (40.6%), Arbidol (6.7%), Xuebijing (7.1%) and Chloroquine phosphate (1.3%). Severe and critical patients received glucocorticoid, Gamma-globulin and oxygen inhalation. Some received mechanic ventilation support. As of 02/27, 161 patients discharged. The median length of hospital stay was 13 days. The 10-, 14-, 20- and 28-day discharge rate was 19.1%, 42.8%, 65.0% and 76.4%, respectively. No hospital-related transmission was observed.


Subject(s)
Antiviral Agents/therapeutic use , Betacoronavirus , Coronavirus Infections/epidemiology , Coronavirus Infections/therapy , Pneumonia, Viral/epidemiology , Pneumonia, Viral/therapy , Respiration, Artificial , Adult , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , COVID-19 , China/epidemiology , Chloroquine/analogs & derivatives , Chloroquine/therapeutic use , Drug Combinations , Drugs, Chinese Herbal/therapeutic use , Female , Glucocorticoids/therapeutic use , Hospitalization , Humans , Immunologic Factors/therapeutic use , Indoles/therapeutic use , Interferons/therapeutic use , Lopinavir/therapeutic use , Male , Middle Aged , Oxygen/therapeutic use , Pandemics , Retrospective Studies , Ritonavir/therapeutic use , SARS-CoV-2 , gamma-Globulins/therapeutic use
8.
Proteomics ; 20(10): e1900310, 2020 05.
Article in English | MEDLINE | ID: mdl-32311217

ABSTRACT

Artemisia annua is well known for biosynthesizing the antimalarial drug artemisinin. Here, a global proteomic profiling of A. annua is conducted with identification of a total of 13 403 proteins based on the genome sequence annotation database. Furthermore, a spectral library is generated to perform quantitative proteomic analysis using data independent acquisition mass spectrometry. Specifically, proteins between two chemotypes that produce high (HAP) and low (LAP) artemisinin content, respectively, are comprehensively quantified and compared. 182 proteins are identified with abundance significantly different between these two chemotypes means after the statistic use the p-value and fold change it is found 182 proteins can reach the demand conditions which represent the expression are significantly different between the high artemisnin content plants (HAPs) and the low artemisnin content plants (LAPs). Data are available via ProteomeXchange with identifier PXD015547. Overall, this current study globally identifies the proteome of A. annua and quantitatively compares the targeted sub-proteomes between the two cultivars of HAP and LAP, providing systematic information on metabolic pathways of A. annua.


Subject(s)
Artemisia annua/genetics , Artemisinins/metabolism , Proteome/genetics , Proteomics , Artemisia annua/metabolism , Gene Expression Regulation, Plant/genetics , Mass Spectrometry
9.
Transl Cancer Res ; 9(4): 2390-2401, 2020 Apr.
Article in English | MEDLINE | ID: mdl-35117599

ABSTRACT

BACKGROUND: Bone metastasis is the third most common metastatic cancers worldwide. It is a group of highly heterogeneous diseases with various potential cancer primaries. Among them, one third was diagnosed as bone metastasis of unknown primary (BMUP) due to lack of indication for the primary tumor even after comprehensive examinations. Thus, the prognosis of BMUP is often very poor since the treatment was largely empirical and untargeted. To assist identification of the primary tumor, a series of molecular markers including traditional tissue-specific histochemistry as well as gene and mRNA markers were developed with moderate to good sensitivity and specificity. METHODS: In this paper, we carried out a comprehensive expression profiling for fresh-frozen tissue samples of bone metastasis from lung, prostate and liver cancers using high resolution, data-independent-acquisition mass spectrometry (DIA-MS). The proteome variation was analyzed and protein classifiers were prioritized. RESULTS: Over 6,000 proteins were quantified from 18 samples, which, to the best of our knowledge, was never achieved before. Further statistical analysis and bioinformatics data mining revealed 4 significant proteins (RFIP1, CK15, ESYT2, and MAL2) with excellent discriminating capabilities with AUCs higher than 0.8. CONCLUSIONS: The comprehensive proteome map of bone metastases will complement available genomic and transcriptomic data. Newly discovered protein classifiers will expand current diagnostic arsenal for tissue of origin studies in BMUP. Furthermore, the proteome map generated in this study by DIA-MS allows future data re-mining as our knowledge advances to assist investigation of bone metastasis and progression of tumors as well as the development of diagnostic tools and prognosis management for BMUPs.

10.
Anal Cell Pathol (Amst) ; 2019: 7653230, 2019.
Article in English | MEDLINE | ID: mdl-31781478

ABSTRACT

Liver metastasis is the most common form of metastatic colorectal cancers during the course of the disease. The global change in protein abundance in liver metastatic colorectal cancers and its role in metastasis establishment have not been comprehensively analyzed. In the present study, fresh-frozen tissue samples including normal colon/localized/liver metastatic CRCs from each recruited patient were analyzed by quantitative proteomics using a multiplexed TMT labeling strategy. Around 5000 protein groups were quantified from all samples. The proteomic profile of localized/metastatic CRCs varied greatly from that of normal colon tissues; differential proteins were mainly from extracellular regions and participate in immune activities, which is crucial for the chronic inflammation signaling pathways in the tumor microenvironment. Further statistical analysis revealed 47 proteins exhibiting statistical significance between localized and metastatic CRCs, of which FILI1P1 and PLG were identified for the first time in proteomic data, which were highly associated with liver metastasis in CRCs.


Subject(s)
Colorectal Neoplasms/pathology , Liver Neoplasms/metabolism , Liver Neoplasms/secondary , Mass Spectrometry , Neoplasm Proteins/metabolism , Proteomics , Colon/metabolism , Colon/pathology , Female , Humans , Male , Middle Aged , Proteome/metabolism
12.
Mol Cell Neurosci ; 90: 22-32, 2018 May 23.
Article in English | MEDLINE | ID: mdl-29802938

ABSTRACT

Neocortical projection neurons consist of intracortical connected upper layer (UL, layer II-IV) neurons and subcortical connected lower layer (LL, layer V-VI) neurons. Afferent activity from the thalamus regulates layer-specific gene expression during postnatal development, which is critical for the formation of proper neocortical cytoarchitecture. Here, we show that activity-dependent gene regulation is confined to UL cortical neurons, but not LL neurons, and that this distinction is likely due to epigenetic modifications of chromatin. We found that the immediate early genes (IEGs), EGR1 and c-FOS, are downregulated in all cortical laminar layers in the absence of afferent activity in vivo. Transcriptional assays demonstrated that EGR1 and c-FOS are able to bind to the promoters of UL- and LL-specific genes to induce transcription. Furthermore, we discovered that LL neurons express higher levels of heterochromatin markers, such as H3K9m3 and H4K20m3, compared to UL neurons. Our results suggest that differential epigenetic modifications of chromatin is an intrinsic mechanism that underlies the different sensitivities of cortical neurons to activity-dependent gene regulation.

13.
Biochem Biophys Res Commun ; 499(4): 856-861, 2018 05 23.
Article in English | MEDLINE | ID: mdl-29625113

ABSTRACT

Exosomes are cell-derived vesicles containing RNA, lipid, and protein, which act in body immune response, intercellular signaling and some other important biological processes. Exosomes have been extensively studied in the past several years on their disease related mechanisms and potential roles to monitor disease progression as biomarkers. Compared with analyzing exosome RNA, comprehensive proteome profiling of exosomes in clinical samples (e.g. blood) are highly demanded but limited mainly due to lack of a reproducible method for efficient exosome extraction. In this study, we evaluated and optimized an exosome preparation approach using one-step ultracentrifugation through an Optiprep™ cushion. Exosomes prepared via this method and analyzed by mass spectrometry using Q-Exactive plus, has led to reproducible identification and quantification of 200 + proteins from human plasma samples of as little as 300 µL. Therefore, such a straightforward exosome extract method has enable us to deeply profile exosome proteomes from human blood at a scale of clinical studies. As a proof of principal, we practiced this approach in analyzing the exosome proteomic profiles of blood samples collected from a sepsis patient during six time points after diagnosis. Among the 238 proteins identified and quantified across the 6 samples, protein SPTLC3 involved in the sphingolipid metabolism, shows a negative correlation (p = 0.02, correlation coefficient = -0.984) with disease progression indicated by body temperature (BD) and C-reactive protein (CRP). Therefore, SPTLC3 could be an interesting target for future study on molecular mechanism of sepsis development, as well as potential classifier to monitor clinical progression of sepsis.


Subject(s)
Disease Progression , Exosomes/metabolism , Plasma/metabolism , Proteome/metabolism , Proteomics/methods , Sepsis/blood , Sepsis/diagnosis , Aged , Humans , Male , Reproducibility of Results , Sepsis/pathology , Time Factors
14.
Virol Sin ; 32(4): 290-297, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28721632

ABSTRACT

Diverse species of rodents and shrews, which are abundant worldwide, harbor a variety of viruses; some of these are closely related to human viruses and possess zoonotic potential. Previously studies have demonstrated that the mammarenavirus and hantavirus carried by rodents or shrews could cause diseases in human population. To determine the distribution of zoonotic viruses in Shenzhen city, the major city in southern China with a high population density, we analyzed 225 rodents (Rattus norvegicus and Rattus flavipectus) and 196 shrews (Suncus murinus) from urban and rural districts for the presence of mammarenavirus, hantavirus, and hepatitis E virus (HEV) by RT-PCR targeting the conserved regions. The infection rates for mammarenavirus, hantaviruses, and HEV in rodents and shrews were 3.56%, 6.89%, and 1.66%, respectively. Partial genome fragment analysis indicated that mammarenavirus and hantavirus strains had more than 90% and 99% nucleic acid identity with Cardamones virus and Seoul virus, respectively, which cause diseases in humans. Although the present HEV strains identified are typically found worldwide, phylogenetic analysis demonstrated a divergence of 16%. To our knowledge, the present work is the first report of the prevalence of mammarenavirus, hantaviruses, and rat HEV strains in rodents and shrews from Shenzhen city, China. Our findings highlight the zoonotic potential of rodent- and shrew-borne mammarenavirus and hantavirus, and the biodiversity of rat HEV isolates in Shenzhen city. The present work suggests that utilization of good hygiene habits is important to minimize the risk of zoonosis.


Subject(s)
Arenaviridae/genetics , Orthohantavirus/isolation & purification , Animals , Arenaviridae/isolation & purification , China , Orthohantavirus/genetics , Hepatitis E/genetics , Rats , Reverse Transcriptase Polymerase Chain Reaction , Shrews , Zoonoses/virology
15.
Neuropharmacology ; 112(Pt A): 46-56, 2017 01.
Article in English | MEDLINE | ID: mdl-27157711

ABSTRACT

Synaptic recruitment of AMPA receptors (AMPARs) represents a key postsynaptic mechanism driving functional development and maturation of glutamatergic synapses. At immature hippocampal synapses, PKA-driven synaptic insertion of GluA4 is the predominant mechanism for synaptic reinforcement. However, the physiological significance and molecular determinants of this developmentally restricted form of plasticity are not known. Here we show that PKA activation leads to insertion of GluA4 to synaptic sites with initially weak or silent AMPAR-mediated transmission. This effect depends on a novel mechanism involving the extreme C-terminal end of GluA4, which interacts with the membrane proximal region of the C-terminal domain to control GluA4 trafficking. In the absence of GluA4, strengthening of AMPAR-mediated transmission during postnatal development was significantly delayed. These data suggest that the GluA4-mediated activation of silent synapses is a critical mechanism facilitating the functional maturation of glutamatergic circuitry during the critical period of experience-dependent fine-tuning. This article is part of the Special Issue entitled 'Ionotropic glutamate receptors'.


Subject(s)
CA1 Region, Hippocampal/metabolism , Cyclic AMP-Dependent Protein Kinases/metabolism , Excitatory Postsynaptic Potentials , Neurons/metabolism , Receptors, AMPA/metabolism , Synapses/metabolism , Animals , CA1 Region, Hippocampal/growth & development , Glutamic Acid/metabolism , Primary Cell Culture , Protein Subunits/metabolism , Protein Transport , Rats, Wistar
16.
Sci Rep ; 6: 23417, 2016 Mar 23.
Article in English | MEDLINE | ID: mdl-27005320

ABSTRACT

Voltage-gated ether à go-go (EAG) K(+) channels are expressed in various types of cancer cells and also in the central nervous system. Aberrant overactivation of human EAG1 (hEAG1) channels is associated with cancer and neuronal disorders such as Zimmermann-Laband and Temple-Baraitser syndromes. Although hEAG1 channels are recognized as potential therapeutic targets, regulation of their functional properties is only poorly understood. Here, we show that the membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP2) is a potent inhibitory gating modifier of hEAG1 channels. PIP2 inhibits the channel activity by directly binding to a short N-terminal segment of the channel important for Ca(2+)/calmodulin (CaM) binding as evidenced by bio-layer interferometry measurements. Conversely, depletion of endogenous PIP2 either by serotonin-induced phospholipase C (PLC) activation or by a rapamycin-induced translocation system enhances the channel activity at physiological membrane potentials, suggesting that PIP2 exerts a tonic inhibitory influence. Our study, combining electrophysiological and direct binding assays, demonstrates that hEAG1 channels are subject to potent inhibitory modulation by multiple phospholipids and suggests that manipulations of the PIP2 signaling pathway may represent a strategy to treat hEAG1 channel-associated diseases.


Subject(s)
Calmodulin/metabolism , Ether-A-Go-Go Potassium Channels/chemistry , Ether-A-Go-Go Potassium Channels/metabolism , Membrane Potentials , Phosphatidylinositol 4,5-Diphosphate/metabolism , Binding Sites , Electrophysiological Phenomena , Gene Expression Regulation , HEK293 Cells , Humans , Membrane Potentials/drug effects , Microscopy, Confocal , Protein Binding , Serotonin/pharmacology , Signal Transduction/drug effects , Sirolimus/pharmacology
17.
Zhonghua Yi Xue Za Zhi ; 95(16): 1226-9, 2015 Apr 28.
Article in Chinese | MEDLINE | ID: mdl-26081506

ABSTRACT

OBJECTIVE: To analyze the phylogeny of the VP1 region of Coxsackie virus A4 (CVA4) from herpangina cases of Shenzhen in 2012 and 2014. METHODS: Real-time reverse transcription(RT)-PCR method was used to test virus such as human enterovirus71, coxsackievirus A16, coxsackievirus A4, coxsackievirus A6 and coxsackievirus A10. The VP1 gene of CVA4 positive samples were amplified by RT-PCR and sequenced. Then the homology and phylogeny analysis of the CVA4 VP1 region was performed. RESULTS: The six CVA4 isolates identified in the herpangina cases during 2012 and 2014 were mostly closed with GIb genotypes. The nucleotide and amino acid homology between them were 94.1% (nucleotide mutation rate was 5.9%) and 98.3%, five amino acid mutation were found in CVA4 strain 2014 of Shenzhen: aa22N-S, aa34T-A, aa63N-S, aa165A-D, aa200T-A. The phylogenetic analysis based on VP1 region demonstrates that CVA4 strain of Shenzhen in 2012 had the nearest genetic relationship with CVA4 strain of Shandong isolated in 2010 (KF150144). However, CVA4 strain of Shenzhen in 2014 had the nearest genetic relationship with CVA4 strain of Jilin (JQ715709) isolated in 2006. CONCLUSIONS: It reveals that all CVA4 strains from the two outbreak of herpangina belong to genotype GIb, the degree of variation in VP1 region of CVA4 strain of Shenzhen in 2014 is obvious compared with that in 2012.There is an obvious difference on internal trend of evolution lineage between the CVA4 strains from 2012 and 2014.


Subject(s)
Enterovirus , Herpangina , China , Genotype , Humans , Mutation Rate , Phylogeny
18.
Cell Cycle ; 11(9): 1773-81, 2012 May 01.
Article in English | MEDLINE | ID: mdl-22510613

ABSTRACT

FNDC3B was recently identified in an oncogenomic screen for amplified oncogenes in hepatocellular carcinoma. It is located at 3q26 and is amplified in over 20% of cancers, usually as part of a broad amplified region encompassing the entire 3q arm. Consistent with an oncogenic role in multiple cancer types, we show here that overexpression of FNDC3B is capable of malignantly transforming mammary and kidney epithelial cells in addition to hepatocytes. To explore how FNDC3B transforms cells, we determined the cellular localization of its gene product and the cancer pathways that it activates. We found that the FNDC3B oncoprotein localizes to the Golgi network, and that its correct localization is essential for its transforming function. We found that overexpression of FNDC3B induces the epithelial-to-mesenchymal transition (EMT) and activates several cancer pathways, including PI3-kinase/Akt, Rb1 and TGFß signaling. For TGFß signaling, we analyzed the point in the pathway at which FNDC3B operates and obtained evidence that it induces expression of all three TGFß ligands and also promotes TGFBR1 cell-surface localization. We found that RNAi-mediated knockdown of FNDC3B in cancer cells with 3q amplification suppressed their clonogenicity and tumorigenicity, but that the same RNAi knockdown had no effect on single-copy 3q cancer cells. These results indicate that FNDC3B is an important oncogenic driver gene of the 3q amplicon, adding to the growing list of oncogenic drivers within this commonly amplified region.


Subject(s)
Cell Transformation, Neoplastic , Chromosomes, Human, Pair 3/genetics , Fibronectins/genetics , Gene Expression Regulation, Neoplastic , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Chromosomes, Human, Pair 3/metabolism , Epithelial-Mesenchymal Transition , Fibronectins/metabolism , Gene Dosage , Gene Knockdown Techniques , Genetic Vectors/genetics , Genetic Vectors/metabolism , Golgi Apparatus/metabolism , Humans , Immunoprecipitation , Oncogenes , Phosphatidylinositol 3-Kinases/genetics , Phosphatidylinositol 3-Kinases/metabolism , Protein Serine-Threonine Kinases/metabolism , RNA Interference , Receptor, Transforming Growth Factor-beta Type I , Receptors, Transforming Growth Factor beta/metabolism , Retroviridae/genetics , Retroviridae/metabolism , Signal Transduction , Transcriptional Activation , Transfection , Transforming Growth Factor beta/metabolism
19.
Cancer Cell ; 19(3): 347-58, 2011 Mar 08.
Article in English | MEDLINE | ID: mdl-21397858

ABSTRACT

We screened 124 genes that are amplified in human hepatocellular carcinoma (HCC) using a mouse hepatoblast model and identified 18 tumor-promoting genes, including CCND1 and its neighbor on 11q13.3, FGF19. Although it is widely assumed that CCND1 is the main driving oncogene of this common amplicon (15% frequency in HCC), both forward-transformation assays and RNAi-mediated inhibition in human HCC cells established that FGF19 is an equally important driver gene in HCC. Furthermore, clonal growth and tumorigenicity of HCC cells harboring the 11q13.3 amplicon were selectively inhibited by RNAi-mediated knockdown of CCND1 or FGF19, as well as by an anti-FGF19 antibody. These results show that 11q13.3 amplification could be an effective biomarker for patients most likely to respond to anti-FGF19 therapy.


Subject(s)
Carcinoma, Hepatocellular/genetics , Fibroblast Growth Factors/genetics , Liver Neoplasms/genetics , Oncogene Proteins/genetics , Animals , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/pharmacology , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Chromosomes, Human, Pair 11/genetics , Cyclin D1/genetics , Cyclin D1/metabolism , Female , Fibroblast Growth Factors/immunology , Fibroblast Growth Factors/metabolism , Gene Amplification , Gene Expression Regulation, Neoplastic , Genetic Predisposition to Disease , Genomics/methods , Humans , Immunoblotting , Liver Neoplasms/drug therapy , Liver Neoplasms/pathology , Mice , Mice, Nude , Oncogene Proteins/metabolism , RNA Interference , Tumor Burden/drug effects , Xenograft Model Antitumor Assays
20.
PLoS One ; 5(1): e8715, 2010 Jan 14.
Article in English | MEDLINE | ID: mdl-20090852

ABSTRACT

BACKGROUND: Specific delivery to synapses of alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptors with long-tailed subunits is believed to be a key event in many forms of activity-dependent changes in synaptic strength. GluA1, the best characterized long-tailed AMPA receptor subunit, contains a C-terminal class I PDZ binding motif, which mediates its interaction with scaffold and trafficking proteins, including synapse-associated protein 97 (SAP97). In GluA4, another long-tailed subunit implicated in synaptic plasticity, the PDZ motif is blocked by a single proline residue. This feature is highly conserved in vertebrates, whereas the closest invertebrate homologs of GluA4 have a canonical class I PDZ binding motif. In this work, we have examined the role of GluA4 in PDZ interactions. METHODOLOGY/PRINCIPAL FINDINGS: Deletion of the carboxy-terminal proline residue of recombinant GluA4 conferred avid binding to SAP97 in cultured cells as shown by coimmunoprecipitation, whereas wild-type GluA4 did not associate with SAP97. Native GluA4 and SAP97 coimmunoprecipitated from mouse brain independently of the GluA1 subunit, supporting the possibility of in vivo PDZ interaction. To obtain evidence for or against the exposure of the PDZ motif by carboxyterminal processing of native GluA4 receptors, we generated an antibody reagent specific for proline-deleted GluA4 C-terminus. Immunoprecipitation and mass spectrometric analyses indicated that the carboxyl-terminus of native GluA4 AMPA receptors is intact and that the postulated single-residue cleavage does not occur to any significant extent. CONCLUSION/SIGNIFICANCE: We conclude that native GluA4 receptors are not capable of canonical PDZ interactions and that their association with SAP97 is likely to be indirect.


Subject(s)
Glutamic Acid/metabolism , PDZ Domains , Receptors, AMPA/metabolism , Adaptor Proteins, Signal Transducing/chemistry , Adaptor Proteins, Signal Transducing/metabolism , Amino Acid Sequence , Animals , Cell Line , Discs Large Homolog 1 Protein , Guanylate Kinases , Humans , Membrane Proteins/chemistry , Membrane Proteins/metabolism , Mice , Molecular Sequence Data , Receptors, AMPA/chemistry , Sequence Homology, Amino Acid , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
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