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2.
J Med Chem ; 67(4): 2487-2511, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38316747

RESUMO

AMG510, as the first approved inhibitor for KRASG12C mutation, has shown promising efficacy in nonsmall-cell lung cancer and colorectal cancer harboring KRASG12C mutation. However, the moderate response rate and the rapid emergence of acquired resistance limit the therapeutic potential of AMG510, highlighting the need for the development of combination strategies. Here, we observed the suppression of RAS-MAPK signaling induced by AMG510 was prolonged and enhanced by SOS1 knockdown. Thus, we design, synthesize, and characterize a potent and specific SOS1 degrader 23. Compound 23 showed efficient SOS1 degradation in KRAS-driven cancer cells and achieved significant antiproliferative potency. Importantly, the combination of 23 with AMG510 suppressed RAS signaling feedback activation, showing synergistic effects against KRASG12C mutant cells in vitro and in vivo. Our findings demonstrated that KRASG12C inhibition plus SOS1 degradation as a potential therapeutic strategy to improve antitumor response and overcome acquired resistance to KRASG12C inhibitor.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Mutação , Neoplasias Pulmonares/tratamento farmacológico
3.
J Med Chem ; 66(18): 12966-12989, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37695288

RESUMO

The NLRP3 inflammasome is a critical component of innate immunity involved in the pathophysiology of various inflammatory diseases. In this study, we designed and synthesized a series of NLRP3 inflammasome inhibitors based on MCC950. Specifically, we optimized the furan moiety, which is considered to be potentially associated with drug-induced liver injury. The representative inhibitor N14, 4-(2-(dimethylamino)ethyl)-N-((1,2,3,5,6,7-hexahydro-s-indacen-4-yl)carbamoyl)benzenesulfonamide, not only maintains the NLRP3 inhibitory activity of MCC950 with IC50 of 25 nM but also demonstrates improved tolerability in human hepatic cells line and mouse primary hepatocytes. In addition, N14 exhibits superior pharmacokinetic properties, with an oral bioavailability of 85.2%. In vivo studies demonstrate that N14 is more effective than MCC950 in multiple NLRP3-related animal model diseases, including nonalcoholic steatohepatitis, lethal septic shock, and colitis. Our research has provided a lead compound that directly targets the NLRP3 inflammasome and can be developed as a novel therapeutic candidate for NLRP3-driven diseases.


Assuntos
Colite , Hepatopatia Gordurosa não Alcoólica , Choque Séptico , Camundongos , Animais , Humanos , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Choque Séptico/tratamento farmacológico , Sulfonas/farmacologia , Colite/tratamento farmacológico , Compostos de Sulfonilureia/uso terapêutico , Camundongos Endogâmicos C57BL , Furanos/farmacologia , Furanos/uso terapêutico
4.
Sci China Life Sci ; 66(2): 211-225, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35829808

RESUMO

Genome-wide association studies have suggested a link between primary open-angle glaucoma and the function of ABCA1. ABCA1 is a key regulator of cholesterol efflux and the biogenesis of high-density lipoprotein (HDL) particles. Here, we showed that the POAG risk allele near ABCA1 attenuated ABCA1 expression in cultured cells. Consistently, POAG patients exhibited lower ABCA1 expression, reduced HDL, and higher cholesterol in white blood cells. Ablation of Abca1 in mice failed to form HDL, leading to elevated cholesterol levels in the retina. Counting retinal ganglion cells (RGCs) by using an artificial intelligence (AI) program revealed that Abca1-deficient mice progressively lost RGCs with age. Single-cell RNA sequencing (scRNA-seq) revealed aberrant oxidative phosphorylation in the Abca1-/- retina, as well as activation of the mTORC1 signaling pathway and suppression of autophagy. Treatment of Abca1-/- mice using atorvastatin reduced the cholesterol level in the retina, thereby improving metabolism and protecting RGCs from death. Collectively, we show that lower ABCA1 expression and lower HDL are risk factors for POAG. Accumulated cholesterol in the Abca1-/- retina causes profound aberrant metabolism, leading to a POAG-like phenotype that can be prevented by atorvastatin. Our findings establish statin use as a preventive treatment for POAG associated with lower ABCA1 expression.


Assuntos
Transportador 1 de Cassete de Ligação de ATP , Colesterol , Células Ganglionares da Retina , Animais , Camundongos , Inteligência Artificial , Atorvastatina , Transportador 1 de Cassete de Ligação de ATP/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Linhagem Celular , Colesterol/metabolismo , Estudo de Associação Genômica Ampla , Glaucoma de Ângulo Aberto , Homeostase , Células Ganglionares da Retina/metabolismo
5.
Artigo em Inglês | MEDLINE | ID: mdl-35154350

RESUMO

Tamoxifen is an effective drug for treating patients with advanced estrogen receptor-positive (ER+) breast cancer (BC), but not for all ER + BC patients. Drug tolerance is the biggest obstacle. In this study, we designed an experiment to investigate whether paeoniflorin affects the ER + BC cell's sensitivity to tamoxifen in the T47D and MCF-7 cell lines. Herein, we found that paeoniflorin inhibited cell proliferation without inducing apoptosis. However, it enhanced tamoxifen-induced apoptosis in both cell lines. Immunoblotting revealed that paeoniflorin significantly increased the already elevated Bax/Bcl2 protein expression ratio and the caspase 3 activity levels, both induced by tamoxifen. Paeoniflorin was also found to increase SIRT4 expression, and deletion of SIRT4 could significantly reverse the inhibition of cell proliferation induced by paeoniflorin and significantly decrease paeoniflorin-enhanced apoptosis induced by tamoxifen. Moreover, protein expression detection revealed that paeoniflorin enhanced the tamoxifen-induced inhibition of STAT3 activation. Besides, the deletion of SIRT4 could significantly increase STAT3 activation in the T47D and MCF-7 cells. In conclusion, paeoniflorin suppressed STAT3 activation to enhance the sensitivity of ER-positive breast cancer cells to tamoxifen through promoting SIRT4 expression.

6.
Transl Vis Sci Technol ; 9(6): 8, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32821505

RESUMO

Purpose: This study aims to develop an impedance-based drug screening platform that will help identify drugs that can enhance the vascular barrier function by stabilizing vascular endothelial cell junctions. Methods: Changes in permeability of cultured human retinal microvascular endothelial cells (HRMECs) monolayer were monitored in real-time with the xCELLigence RTCA system. Using this platform, we performed a primary screen of 2100 known drugs and confirmed hits using two additional secondary permeability assays: the transwell permeability assay and the XPerT assay. The cellular and molecular mechanisms of action and in vivo therapeutic efficacy were also assessed. Results: Eleven compounds blocked interleukin 1 beta (IL-1ß) induced hyperpermeability in the primary screen. Two of 11 compounds, apigenin and ethaverine hydrochloride, reproducibly blocked multiple cytokines induced hyperpermeability. In addition to HRMEC monolayers, the two compounds stabilized three other types of primary vascular endothelial cell monolayers. Preliminary mechanistic studies suggest that the two compounds stabilize the endothelium by blocking ADP-ribosylation factor 6 (ARF6) activation, which results in enhanced VE-cadherin membrane localization. The two compounds showed in vivo efficacy in an animal model of retinal permeability. Conclusions: We developed an impedance-based cellular phenotypic drug screening platform that can identify drugs that enhance vascular barrier function. We found apigenin and ethaverine hydrochloride stabilize endothelial cell junctions and enhance the vascular barrier by blocking ARF6 activation and increasing VE-cadherin membrane localization. Translational Relevance: The drugs identified from the phenotypic screen would have potential therapeutic efficacy in retinal vascular diseases regardless of the underlying mechanisms that promote vascular leak.


Assuntos
Permeabilidade Capilar , Células Endoteliais , Fator 6 de Ribosilação do ADP , Animais , Apigenina/farmacologia , Barreira Hematorretiniana , Humanos , Papaverina/análogos & derivados
7.
J Food Drug Anal ; 26(1): 409-415, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29389581

RESUMO

Pramlintide acetate (Symlin®), a synthetic analogue of the human hormone amylin. It was approved in March 2005 as a subcutaneous injection for the adjunctive treatment of patients who have type 1 or 2 diabetes mellitus. The objective of current investigation was to study the degradation behavior of pramlintide acetate under different ICH recommended stress conditions by HPLC and LC-MS. Pramlintide acetate was subjected to stress conditions of hydrolysis (acidic or alkaline), oxidation, photolysis and thermal decomposition. Extensive degradation products were observed under the hydrolysis, oxidation or thermal stress conditions, while minimal degradation was found in the photolytic conditions. Successful separation of drug from the degradation products was achieved by the validated chromatography (RP-HPLC and SCX-HPLC) methods. Subsequent to isolation, the molecular weight of each component was determined by LC-MS. The LC-MS m/z values and fragmentation patterns of 4 impurities matched with the predicted degradation products of pramlintide acetate.


Assuntos
Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Polipeptídeo Amiloide das Ilhotas Pancreáticas/análise , Polipeptídeo Amiloide das Ilhotas Pancreáticas/química , Espectrometria de Massas em Tandem , Estabilidade de Medicamentos , Humanos , Hidrólise , Polipeptídeo Amiloide das Ilhotas Pancreáticas/isolamento & purificação , Oxirredução , Fotólise , Temperatura
8.
J Clin Invest ; 127(12): 4569-4582, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29058688

RESUMO

The devastating sequelae of diabetes mellitus include microvascular permeability, which results in retinopathy. Despite clinical and scientific advances, there remains a need for new approaches to treat retinopathy. Here, we have presented a possible treatment strategy, whereby targeting the small GTPase ARF6 alters VEGFR2 trafficking and reverses signs of pathology in 4 animal models that represent features of diabetic retinopathy and in a fifth model of ocular pathological angiogenesis. Specifically, we determined that the same signaling pathway utilizes distinct GEFs to sequentially activate ARF6, and these GEFs exert distinct but complementary effects on VEGFR2 trafficking and signal transduction. ARF6 activation was independently regulated by 2 different ARF GEFs - ARNO and GEP100. Interaction between VEGFR2 and ARNO activated ARF6 and stimulated VEGFR2 internalization, whereas a VEGFR2 interaction with GEP100 activated ARF6 to promote VEGFR2 recycling via coreceptor binding. Intervening in either pathway inhibited VEGFR2 signal output. Finally, using a combination of in vitro, cellular, genetic, and pharmacologic techniques, we demonstrated that ARF6 is pivotal in VEGFR2 trafficking and that targeting ARF6-mediated VEGFR2 trafficking has potential as a therapeutic approach for retinal vascular diseases such as diabetic retinopathy.


Assuntos
Fatores de Ribosilação do ADP/metabolismo , Retinopatia Diabética/metabolismo , Transdução de Sinais , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Fator 6 de Ribosilação do ADP , Fatores de Ribosilação do ADP/genética , Linhagem Celular , Retinopatia Diabética/genética , Retinopatia Diabética/patologia , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Humanos , Transporte Proteico , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética
9.
Sci Rep ; 7(1): 9296, 2017 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-28839191

RESUMO

Phosphatidylserine (PS) is asymmetrically distributed between the outer and inner leaflets of the plasma membrane in eukaryotic cells. PS asymmetry on the plasma membrane depends on the activities of P4-ATPases, and disruption of PS distribution can lead to various disease conditions. Folding and transporting of P4-ATPases to their cellular destination requires the ß subunit TMEM30A proteins. However, the in vivo functions of Tmem30a remain unknown. To this end, we generated retinal-specific Tmem30a-knockout mice to investigate its roles in vivo for the first time. Our data demonstrated that loss of Tmem30a in mouse cone cells leads to mislocalization of cone opsin, loss of photopic electroretinogram (ERG) responses and loss of cone cells. Mechanistically, Tmem30a-mutant mouse embryonic fibroblasts (MEFs) exhibited diminished PS flippase activity and increased exposure of PS on the cell surface. The broad loss of Tmem30a in adult mice led to a reduced scotopic photoresponse, mislocalization of ATP8A2 to the inner segment and cell body, and increased apoptosis in the retina. Our data demonstrated novel essential roles of Tmem30a in the retina.


Assuntos
Visão de Cores , Proteínas de Membrana/metabolismo , Opsinas/metabolismo , Retina/patologia , Células Fotorreceptoras Retinianas Cones/patologia , Adenosina Trifosfatases/metabolismo , Animais , Apoptose , Células Cultivadas , Eletrorretinografia , Proteínas de Membrana/deficiência , Camundongos Knockout , Visão Noturna , Fosfatidilserinas/metabolismo , Proteínas de Transferência de Fosfolipídeos/metabolismo , Transporte Proteico
10.
BMC Med Genet ; 18(1): 69, 2017 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-28651521

RESUMO

BACKGROUND: Many osteoarthritis (OA) susceptibility genes have been identified in recent years. Given the overlap in the phenotype of joint inflammation between OA and Kashin-Beck disease (KBD), the aim of this study is to explore whether the reported OA susceptibility genes and two genes that may link to OA pathophysiology are associated with KBD in the Tibetan population. METHOD: Fifteen single-nucleotide polymorphisms (SNPs) in 12 candidate genes previously reported as OA susceptibility loci were selected for investigation. Genotyping was performed using the SNaPshot method for these SNPs in a Tibetan population composed of 849 KBD patients and 565 normal controls. Meanwhile, the coding regions of two genes, COL10A1 and HABP2, which may involve in the pathological mechanism of OA/KBD, were sequenced by Sanger sequencing to identify susceptibility coding variants for KBD in the Tibetan population. RESULTS: The two arthritis-susceptible candidate SNPs, rs7775 (p.Arg324Gly) in the FRZB gene and rs7033979 in the ASPN gene, showed associations with KBD (OR = 1.568, P = 4 × 10-3 and OR = 0.744, P = 8 × 10-3, respectively). The coding variants rs142463796 (p.Asp128Asn) and rs2228547 (p.Gly545Arg) in the COL10A1 gene (OR = 9.832 and P = 6 × 10-3 and OR = 1.242, P = 0.043, respectively) and rs548354451 (p.Asp272Glu) in the HABP2 gene (OR = 2.813, P = 0.010) were associated with KBD patients. CONCLUSION: These finding suggested that rs7775 in the FRZB gene may increase susceptibility to KBD, while rs7033979 in the ASPN gene may play a protective role in susceptibility to KBD in Tibetans. Moreover, genetic variants in chondrogenesis-related genes COL10A1 and HABP2 may play a role in the risk of developing KBD in the Tibetan population.


Assuntos
Predisposição Genética para Doença , Doença de Kashin-Bek/genética , Colágeno Tipo X/genética , Feminino , Estudos de Associação Genética , Glicoproteínas/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Serina Endopeptidases/genética , Tibet
11.
Genet Test Mol Biomarkers ; 20(7): 346-51, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27228167

RESUMO

BACKGROUND: Familial exudative vitreoretinopathy (FEVR, OMIM 133780) is a severe inherited retinal disorder characterized by incomplete retinal vascular development and neovascularization. At least five genes have been reported to be associated with FEVR, including NDP, LRP5, FZD4, TSPAN12, and ZNF408. Recently reported data showed that mutations in the KIF11 gene can also lead to FEVR conditions. Previous studies suggested that known mutations only explain approximately 40-60% of FEVR cases in different populations. PURPOSE: To investigate the causative genetic mutations in four Indian families with FEVR. METHODS: Whole exome sequencing was carried out to analyze the genomic DNA samples from the four FEVR proband patients and Sanger sequencing was utilized to verify all identified polymorphisms. A luciferase assay was used to test the mutant protein activity. RESULTS: We identified four novel LRP5 missense mutations in these FEVR families: c.C1042T (p.R348W), c.G1141A (p.D381N), c.C1870T (p.R624W), and c.A4550G (p.Y1517C). The luciferase assay demonstrated that all four of these LRP5 mutations led to significant reduction of enzymatic activity with response to NORRIN, suggesting that they are pathogenic. CONCLUSION: Our findings expand the mutational spectrum of FEVR in the Indian population and provide some guidelines in clinical diagnosis.


Assuntos
Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Doenças Retinianas/genética , Adolescente , Adulto , Sequência de Aminoácidos/genética , Povo Asiático/genética , Sequência de Bases , Pré-Escolar , Análise Mutacional de DNA , Exoma , Oftalmopatias Hereditárias , Vitreorretinopatias Exsudativas Familiares , Feminino , Predisposição Genética para Doença , Humanos , Índia , Recém-Nascido , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação , Mutação de Sentido Incorreto , Linhagem , Fenótipo , Polimorfismo Genético , Doenças Retinianas/metabolismo
12.
Nat Genet ; 48(6): 640-7, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27089177

RESUMO

Polypoidal choroidal vasculopathy (PCV), a subtype of 'wet' age-related macular degeneration (AMD), constitutes up to 55% of cases of wet AMD in Asian patients. In contrast to the choroidal neovascularization (CNV) subtype, the genetic risk factors for PCV are relatively unknown. Exome sequencing analysis of a Han Chinese cohort followed by replication in four independent cohorts identified a rare c.986A>G (p.Lys329Arg) variant in the FGD6 gene as significantly associated with PCV (P = 2.19 × 10(-16), odds ratio (OR) = 2.12) but not with CNV (P = 0.26, OR = 1.13). The intracellular localization of FGD6-Arg329 is distinct from that of FGD6-Lys329. In vitro, FGD6 could regulate proangiogenic activity, and oxidized phospholipids increased expression of FGD6. FGD6-Arg329 promoted more abnormal vessel development in the mouse retina than FGD6-Lys329. Collectively, our data suggest that oxidized phospholipids and FGD6-Arg329 might act synergistically to increase susceptibility to PCV.


Assuntos
Fatores de Troca do Nucleotídeo Guanina/genética , Mutação de Sentido Incorreto , Degeneração Macular Exsudativa/genética , Células Cultivadas , China , Estudos de Coortes , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Etnicidade , Perfilação da Expressão Gênica , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Polimorfismo de Nucleotídeo Único , Frações Subcelulares/metabolismo
13.
Sci Rep ; 5: 16120, 2015 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-26530129

RESUMO

Familial exudative vitreoretinopathy (FEVR) is a hereditary eye disease characterized by defects in the development of retinal vessels. However, known genetic mutations can only explain approximately 50% of FEVR patients. To assess the mutation frequency of Frizzled 4 (FZD4) in Chinese patients, we analysed patients with FEVR from 61 families from China to identify mutations in FZD4 and to study the effects of identified mutations on FZD4 function. All coding exons and adjacent intronic regions of FZD4 were amplified by polymerase chain reaction and subjected to Sanger sequencing analysis. Three mutations in the FZD4 gene were identified in these families. Of these, two were novel mutations: p.E134* and p.T503fs. Both mutations involve highly conserved residues and were not present in 800 normal individuals. Each of these two novel FZD4 mutations was introduced into wild-type FZD4 cDNA by site-directed mutagenesis. Wild-type and mutant FZD4 DNAs were introduced into HEK293 cells to analyse the function of FZD4 in Norrin-dependent activation of the Norrin/ß-catenin pathway using luciferase reporter assays. Both the p.E134* and p.T503fs mutants failed to induce luciferase reporter activity in response to Norrin. Our study identified two novel FZD4 mutations in Chinese patients with FEVR.


Assuntos
Povo Asiático/genética , Receptores Frizzled/genética , Doenças Retinianas/genética , Adulto , Angiografia , Sequência de Bases , Pré-Escolar , China , Oftalmopatias Hereditárias , Proteínas do Olho/metabolismo , Vitreorretinopatias Exsudativas Familiares , Feminino , Receptores Frizzled/metabolismo , Genótipo , Células HEK293 , Humanos , Masculino , Mutagênese Sítio-Dirigida , Proteínas do Tecido Nervoso/metabolismo , Linhagem , Fenótipo , Polimorfismo de Nucleotídeo Único , Doenças Retinianas/patologia , Via de Sinalização Wnt , beta Catenina/metabolismo
14.
PLoS One ; 10(10): e0140370, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26469335

RESUMO

Vitamin D is a known modulator of inflammation. Native dietary vitamin D3 is thought to be bio-inactive, and beneficial vitamin D3 effects are thought to be largely mediated by the metabolite 1,25(OH)2D3. Reduced serum levels of the most commonly measured precursor metabolite, 25(OH)D3, is linked to an increased risk of multiple inflammatory diseases, including: cardiovascular disease, arthritis, multiple sclerosis, and sepsis. Common to all of these diseases is the disruption of endothelial stability and an enhancement of vascular leak. We previously performed an unbiased chemical suppressor screen on a genetic model of vascular instability, and identified cholecalciferol (D3, dietary Vitamin D3) as a factor that had profound and immediate stabilizing and therapeutic effects in that model. In this manuscript we show that the presumed inactive sterol, D3, is actually a potent and general mediator of endothelial stability at physiologically relevant concentrations. We further demonstrate that this phenomenon is apparent in vitamin D3 metabolites 25(OH)D3 and 1,25(OH)2D3, and that the effects are independent of the canonical transcription-mediated vitamin D pathway. Our data suggests the presence of an alternative signaling modality by which D3 acts directly on endothelial cells to prevent vascular leak. The finding that D3 and its metabolites modulate endothelial stability may help explain the clinical correlations between low serum vitamin D levels and the many human diseases with well-described vascular dysfunction phenotypes.


Assuntos
Colecalciferol/farmacologia , Endotélio Vascular/efeitos dos fármacos , Vitaminas/farmacologia , Animais , Permeabilidade Capilar , Células Cultivadas , Colecalciferol/análogos & derivados , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Humanos , Camundongos
15.
J Hum Genet ; 60(10): 625-30, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26246154

RESUMO

Retinitis pigmentosa (RP) is a heterogenous group of inherited retinal degenerations caused by mutations in at least 50 genes. To identify genetic mutations underlying autosomal recessive RP (arRP), we performed whole-exome sequencing study on two consanguineous marriage Indian families (RP-252 and RP-182) and 100 sporadic RP patients. Here we reported novel mutation in FAM161A in RP-252 and RP-182 with two patients affected with RP in each family. The FAM161A gene was identified as the causative gene for RP28, an autosomal recessive form of RP. By whole-exome sequencing we identified several homozygous genomic regions, one of which included the recently identified FAM161A gene mutated in RP28-linked arRP. Sequencing analysis revealed the presence of a novel homozygous frameshift mutation p.R592FsX2 in both patients of family RP-252 and family RP-182. In 100 sporadic Indian RP patients, this novel homozygous frameshift mutation p.R592FsX2 was identified in one sporadic patient ARRP-S-I-46 by whole-exome sequencing and validated by Sanger sequencing. Meanwhile, this homozygous frameshift mutation was absent in 1000 ethnicity-matched control samples screened by direct Sanger sequencing. In conclusion, we identified a novel homozygous frameshift mutations of RP28-linked RP gene FAM161A in Indian population.


Assuntos
Exoma , Proteínas do Olho/genética , Mutação da Fase de Leitura , Homozigoto , Linhagem , Retinose Pigmentar/genética , Feminino , Genes Recessivos , Estudo de Associação Genômica Ampla , Humanos , Índia , Masculino
16.
Mol Vis ; 20: 1296-306, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25352738

RESUMO

PURPOSE: Familial exudative vitreoretinopathy (FEVR) is a group of inherited blinding eye diseases characterized by defects in the development of the retinal vessels. Recent studies have identified genetic variants in tetraspanin 12 (TSPAN12) as a cause of FEVR. The purpose of this study was to identify novel TSPAN12 mutations in Chinese patients with FEVR and to describe the associated phenotypes. METHODS: Mutation screening was performed by directly sequencing PCR products of genomic DNA with primers designed to amplify the seven coding exons and adjacent intronic regions of the FEVR-causing gene TSPAN12. Clinical phenotypes of the patients with TSPAN12 mutations were documented. Wild-type and mutant TSPAN12 proteins were assayed for the Norrin-ß-catenin signaling pathway with luciferase reporter assays. RESULTS: Three novel heterozygous mutations in TSPAN12 were identified: c.566G>A (p.C189Y), c.177delC (p.Y59fsX67), and c.C254T (p.T85M). All three mutations involved highly conserved residues and were not present in 200 normal individuals. Ocular phenotypes included increased ramification of the peripheral retinal vessels, a peripheral avascular zone, inferotemporal dragging of the optic disc and macula, and retinal folds. The probands showed relatively severe retinopathy, whereas the other family members were often asymptomatic. In SuperTopFlash (STF) cell line transfection studies, C189Y, Y59fsX67, and T85M mutants failed to induce luciferase reporter activity in response to Norrin. CONCLUSIONS: We found three novel TSPAN12 mutations in Chinese patients with autosomal dominant FEVR, and suggest that TSPAN12 mutations cause FEVR. The phenotypes associated with the TSPAN12 mutations showed extensive variation in disease severity among members of the same family, which implied the complexity of FEVR mutations and phenotypes.


Assuntos
Heterogeneidade Genética , Mutação , Fenótipo , Tetraspaninas/genética , Adolescente , Sequência de Aminoácidos , Povo Asiático , Sequência de Bases , Bioensaio , Estudos de Casos e Controles , Criança , Pré-Escolar , Éxons , Oftalmopatias Hereditárias , Proteínas do Olho/genética , Vitreorretinopatias Exsudativas Familiares , Feminino , Genótipo , Humanos , Lactente , Íntrons , Masculino , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/genética , Retina/metabolismo , Retina/patologia , Doenças Retinianas/etnologia , Doenças Retinianas/genética , Doenças Retinianas/patologia , Índice de Gravidade de Doença , beta Catenina/genética
17.
Mol Vis ; 20: 395-409, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24715757

RESUMO

PURPOSE: To investigate the clinical features and disease-causing mutations in two Chinese families with familial exudative vitreoretinopathy (FEVR). METHODS: Clinical data and genomic DNA were collected for patients with FEVR. The coding exons and adjacent intronic regions of FZD4, LRP5, TSPAN12, and NDP were amplified with PCR, and the resulting amplicons were analyzed with Sanger sequencing. Wild-type and mutant LRP5 proteins were assayed for the Norrin/ß-catenin pathway by luciferase reporter assays. RESULTS: Two novel heterozygous mutations in the LRP5 gene were identified in two relatives--p.A422T and p.L540P. Typical FEVR fundus change and mild reduced bone mineral density (BMD) was found in the two patients and the affected parent. In the luciferase studies, both p.A422T and p.L540P mutants displayed a significant reduction of the luciferase activity in SuperTopFlash (STF) cells in response to Norrin (87% reduction for p.A422T and 97% reduction for p.L540P). Both patients had an additional LRP5 sequence change (p.Q816P in Patient 1 from the unaffected mother and p.T852M in Patient 2 verified as a new mutation). Luciferase assay showed no reduction for p.Q816P and 94.9% reduction for the new mutation p.T852M, suggesting that p.Q816P may be not pathogenic and p.T852M may be pathogenic. CONCLUSIONS: Our findings demonstrated two new novel LRP5 mutations in Chinese patients with FEVR and mild reduced BMD. They emphasize the complexity of FEVR mutations and phenotypes.


Assuntos
Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Mutação/genética , Vitreorretinopatia Proliferativa/genética , Sequência de Aminoácidos , Sequência de Bases , Criança , Família , Feminino , Fundo de Olho , Genes Dominantes , Genes Reporter , Heterozigoto , Humanos , Lactente , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/química , Luciferases/metabolismo , Masculino , Dados de Sequência Molecular , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Linhagem , Alinhamento de Sequência , Transdução de Sinais/genética
18.
Cell Signal ; 26(3): 619-28, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24333668

RESUMO

New negative regulators of interferon (IFN) signaling, preferably with tissue specificity, are needed to develop therapeutic means to enhance the efficacy of type I IFNs (IFN-α/ß) and reduce their side effects. We conducted cell-based screening for IFN signaling enhancer and discovered that luteolin, a natural flavonoid, sensitized the antiproliferative effect of IFN-α in hepatoma HepG2 cells and cervical carcinoma HeLa cells. Luteolin promoted IFN-ß-induced Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway activation by enhancing the phosphorylation of Jak1, Tyk2, and STAT1/2, thereby promoting STAT1 accumulation in the nucleus and endogenous IFN-α-regulated gene expression. Of interest, inhibition of phosphodiesterase (PDE) abolished the effect of IFN-ß and luteolin on STAT1 phosphorylation. Luteolin also increased the cAMP-degrading activity of PDE bound with type I interferon receptor 2 (IFNAR2) and decreased the intracellular cAMP level, indicating that luteolin may act on the JAK/STAT pathway via PDE. Protein kinase A (PKA) was found to negatively regulate IFN-ß-induced JAK/STAT signaling, and its inhibitory effect was counteracted by luteolin. Pull-down and immunoprecipitation assays revealed that type II PKA interacted with IFNAR2 via the receptor for activated C-kinase 1 (RACK-1), and such interaction was inhibited by luteolin. Src homology domain 2 containing tyrosine phosphatase-2 (SHP-2) was further found to mediate the inhibitory effect of PKA on the JAK/STAT pathway. These data suggest that PKA/PDE-mediated cAMP signaling, integrated by RACK-1 to IFNAR2, may negatively regulate IFN signaling through SHP-2. Inhibition of this signaling may provide a new way to sensitize the efficacy of IFN-α/ß.


Assuntos
Interferon-alfa/farmacologia , Interferon beta/farmacologia , Janus Quinase 1/metabolismo , Luteolina/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores , Adjuvantes Imunológicos/farmacologia , Anticorpos/imunologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Colforsina/farmacologia , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/química , Proteínas de Ligação ao GTP , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Fatores Imunológicos/farmacologia , Janus Quinase 1/antagonistas & inibidores , Janus Quinase 1/imunologia , Proteínas de Neoplasias , Inibidores de Fosfodiesterase/farmacologia , Diester Fosfórico Hidrolases/metabolismo , Fosforilação/efeitos dos fármacos , Receptor de Interferon alfa e beta/química , Receptor de Interferon alfa e beta/metabolismo , Receptores de Quinase C Ativada , Receptores de Superfície Celular , Fator de Transcrição STAT1/antagonistas & inibidores , Fator de Transcrição STAT1/imunologia , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT2/antagonistas & inibidores , Fator de Transcrição STAT2/imunologia , Fator de Transcrição STAT2/metabolismo , Transdução de Sinais/efeitos dos fármacos , TYK2 Quinase/imunologia , TYK2 Quinase/metabolismo
19.
J Comput Chem ; 32(13): 2942-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21728180

RESUMO

BACKGROUND: To manage chemical structures in small laboratories is one of the important daily tasks. Few solutions are available on the internet, and most of them are closed source applications. The open-source applications typically have limited capability and basic cheminformatics functionalities. In this article, we describe an open-source solution to manage chemicals in research groups based on open source and free components. It has a user-friendly interface with the functions of chemical handling and intensive searching. RESULTS: MyMolDB is a micromolecular database solution that supports exact, substructure, similarity, and combined searching. This solution is mainly implemented using scripting language Python with a web-based interface for compound management and searching. Almost all the searches are in essence done with pure SQL on the database by using the high performance of the database engine. Thus, impressive searching speed has been archived in large data sets for no external Central Processing Unit (CPU) consuming languages were involved in the key procedure of the searching. AVAILABILITY: MyMolDB is an open-source software and can be modified and/or redistributed under GNU General Public License version 3 published by the Free Software Foundation (Free Software Foundation Inc. The GNU General Public License, Version 3, 2007. Available at: http://www.gnu.org/licenses/gpl.html). The software itself can be found at http://code.google.com/p/mymoldb/.


Assuntos
Sistemas de Gerenciamento de Base de Dados , Sistemas de Gerenciamento de Base de Dados/economia , Sistemas de Gerenciamento de Base de Dados/tendências , Bases de Dados Factuais/economia , Bases de Dados Factuais/tendências , Estrutura Molecular , Ferramenta de Busca/economia , Ferramenta de Busca/tendências , Fatores de Tempo , Interface Usuário-Computador
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