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1.
J Biol Chem ; 300(2): 105650, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38237681

RESUMO

Individual oncogenic KRAS mutants confer distinct differences in biochemical properties and signaling for reasons that are not well understood. KRAS activity is closely coupled to protein dynamics and is regulated through two interconverting conformations: state 1 (inactive, effector binding deficient) and state 2 (active, effector binding enabled). Here, we use 31P NMR to delineate the differences in state 1 and state 2 populations present in WT and common KRAS oncogenic mutants (G12C, G12D, G12V, G13D, and Q61L) bound to its natural substrate GTP or a commonly used nonhydrolyzable analog GppNHp (guanosine-5'-[(ß,γ)-imido] triphosphate). Our results show that GppNHp-bound proteins exhibit significant state 1 population, whereas GTP-bound KRAS is primarily (90% or more) in state 2 conformation. This observation suggests that the predominance of state 1 shown here and in other studies is related to GppNHp and is most likely nonexistent in cells. We characterize the impact of this differential conformational equilibrium of oncogenic KRAS on RAF1 kinase effector RAS-binding domain and intrinsic hydrolysis. Through a KRAS G12C drug discovery, we have identified a novel small-molecule inhibitor, BBO-8956, which is effective against both GDP- and GTP-bound KRAS G12C. We show that binding of this inhibitor significantly perturbs state 1-state 2 equilibrium and induces an inactive state 1 conformation in GTP-bound KRAS G12C. In the presence of BBO-8956, RAF1-RAS-binding domain is unable to induce a signaling competent state 2 conformation within the ternary complex, demonstrating the mechanism of action for this novel and active-conformation inhibitor.


Assuntos
Proteínas Proto-Oncogênicas p21(ras) , Proteínas ras , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteínas ras/metabolismo , Guanosina Trifosfato/metabolismo , Espectroscopia de Ressonância Magnética , Transdução de Sinais , Mutação
2.
Anal Chem ; 96(13): 5223-5231, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38498381

RESUMO

Development of new targeted inhibitors for oncogenic KRAS mutants may benefit from insight into how a given mutation influences the accessibility of protein residues and how compounds interact with mutant or wild-type KRAS proteins. Targeted proteomic analysis, a key validation step in the KRAS inhibitor development process, typically involves both intact mass- and peptide-based methods to confirm compound localization or quantify binding. However, these methods may not always provide a clear picture of the compound binding affinity for KRAS, how specific the compound is to the target KRAS residue, and how experimental conditions may impact these factors. To address this, we have developed a novel top-down proteomic assay to evaluate in vitro KRAS4B-compound engagement while assessing relative quantitation in parallel. We present two applications to demonstrate the capabilities of our assay: maleimide-biotin labeling of a KRAS4BG12D cysteine mutant panel and treatment of three KRAS4B proteins (WT, G12C, and G13C) with small molecule compounds. Our results show the time- or concentration-dependence of KRAS4B-compound engagement in context of the intact protein molecule while directly mapping the compound binding site.


Assuntos
Proteômica , Proteínas Proto-Oncogênicas p21(ras) , Proteínas Proto-Oncogênicas p21(ras)/genética , Mutação , Sítios de Ligação
3.
Int J Mol Sci ; 23(23)2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36499641

RESUMO

Huntington's disease (HD) is caused by the production of mutant Huntingtin (mHTT), characterized by long polyglutamine repeats with toxic effects. There are currently no clinically validated therapeutic agents that slow or halt HD progression, resulting in a significant clinical unmet need. The striatum-derived STHdh cell line, generated from mHTT knock-in mouse embryos (STHdhQ111/Q111), represents a useful model to study mechanisms behind pathogenesis of HD and to investigate potential new therapeutic targets. Indeed, these cells show susceptibility to nucleolar stress, activated DNA damage response and apoptotic signals, and elevated levels of H3K9me3 that all together concur in the progressive HD pathogenesis. We have previously shown that the adeno-associated viral vector-mediated delivery of the longevity-associated variant (LAV) of BPIFB4 prevents HD progression in a mouse model of HD. Here, we show that LAV-BPIFB4 stably infected in STHdhQ111/Q111 cells reduces (i) nucleolar stress and DNA damage through the improvement of DNA repair machinery, (ii) apoptosis, through the inhibition of the caspase 3 death signaling, and (iii) the levels of H3K9me3, by accelerating the histone clearance, via the ubiquitin-proteasome pathway. These findings pave the way to propose LAV-BPIFB4 as a promising target for innovative therapeutic strategies in HD.


Assuntos
Doença de Huntington , Animais , Camundongos , Apoptose/genética , Corpo Estriado/metabolismo , Modelos Animais de Doenças , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo , Doença de Huntington/metabolismo , Neostriado/metabolismo , Neuroproteção/genética , Variação Genética
4.
Aging Clin Exp Res ; 33(9): 2369-2377, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33170488

RESUMO

Bitter taste receptors (TAS2R) are involved in a variety of non-tasting physiological processes, including immune-inflammatory ones. Therefore, their genetic variations might influence various traits. In particular, in different populations of South Italy (Calabria, Cilento, and Sardinia), polymorphisms of TAS2R16 and TAS238 have been analysed in association with longevity with inconsistent results. A meta-analytic approach to quantitatively synthesize the possible effect of the previous variants and, possibly, to reconcile the inconsistencies has been used in the present paper. TAS2R38 variants in the Cilento population were also analysed for their possible association with longevity and the obtained data have been included in the relative meta-analysis. In population from Cilento no association was found between TAS2R38 and longevity, and no association was observed as well, performing the meta-analysis with data of the other studies. Concerning TAS2R16 gene, instead, the genotype associated with longevity in the Calabria population maintained its significance in the meta-analysis with data from Cilento population, that, alone, were not significant in the previously published study. In conclusion, our results suggest that TAS2R16 genotype variant is associated with longevity in South Italy.


Assuntos
Longevidade , Paladar , Genótipo , Humanos , Longevidade/genética , Polimorfismo de Nucleotídeo Único , Receptores Acoplados a Proteínas G/genética , Paladar/genética
5.
Eur Heart J ; 41(26): 2487-2497, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-31289820

RESUMO

AIMS: Here, we aimed to determine the therapeutic effect of longevity-associated variant (LAV)-BPIFB4 gene therapy on atherosclerosis. METHODS AND RESULTS: ApoE knockout mice (ApoE-/-) fed a high-fat diet were randomly allocated to receive LAV-BPIFB4, wild-type (WT)-BPIFB4, or empty vector via adeno-associated viral vector injection. The primary endpoints of the study were to assess (i) vascular reactivity and (ii) atherosclerotic disease severity, by Echo-Doppler imaging, histology and ultrastructural analysis. Moreover, we assessed the capacity of the LAV-BPIFB4 protein to shift monocyte-derived macrophages of atherosclerotic mice and patients towards an anti-inflammatory phenotype. LAV-BPIFB4 gene therapy rescued endothelial function of mesenteric and femoral arteries from ApoE-/- mice; this effect was blunted by AMD3100, a CXC chemokine receptor type 4 (CXCR4) inhibitor. LAV-BPIFB4-treated mice showed a CXCR4-mediated shift in the balance between Ly6Chigh/Ly6Clow monocytes and M2/M1 macrophages, along with decreased T cell proliferation and elevated circulating levels of interleukins IL-23 and IL-27. In vitro conditioning with LAV-BPIFB4 protein of macrophages from atherosclerotic patients resulted in a CXCR4-dependent M2 polarization phenotype. Furthermore, LAV-BPIFB4 treatment of arteries explanted from atherosclerotic patients increased the release of atheroprotective IL-33, while inhibiting the release of pro-inflammatory IL-1ß, inducing endothelial nitric oxide synthase phosphorylation and restoring endothelial function. Finally, significantly lower plasma BPIFB4 was detected in patients with pathological carotid stenosis (>25%) and intima media thickness >2 mm. CONCLUSION: Transfer of the LAV of BPIFB4 reduces the atherogenic process and skews macrophages towards an M2-resolving phenotype through modulation of CXCR4, thus opening up novel therapeutic possibilities in cardiovascular disease.


Assuntos
Aterosclerose , Placa Aterosclerótica , Idoso , Animais , Apolipoproteínas E , Aterosclerose/genética , Espessura Intima-Media Carotídea , Feminino , Humanos , Inflamação , Peptídeos e Proteínas de Sinalização Intercelular , Longevidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Knockout para ApoE , Pessoa de Meia-Idade , Fosfoproteínas , Receptores CXCR4
6.
Immun Ageing ; 16: 5, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30833980

RESUMO

BACKGROUND: Innate immunity utilizes components of sensory signal transduction such as bitter and sweet taste receptors. In fact, empirical evidence has shown bitter and sweet taste receptors to be an integral component of antimicrobial immune response in upper respiratory tract infections. Since an efficient immune response plays a key role in the attainment of longevity, it is not surprising that the rs978739 polymorphism of the bitter taste receptor TAS2R16 gene has been shown to be associated with longevity in a population of 941 individuals ranging in age from 20 to 106 years from Calabria (Italy). There are many possible candidate genes for human longevity, however of the many genes tested, only APOE and FOXO3 survived to association in replication studies. So, it is necessary to validate in other studies genes proposed to be associated with longevity. Thus, we analysed the association of the quoted polymorphism in a population of long lived individuals (LLIs) and controls from another Italian population from Cilento. METHODS: The analysis has been performed on data previously obtained with genome-wide association study on a population of LLIs (age range 90-109 years) and young controls (age range 18-45 years) from Cilento (Italy). RESULTS: Statistical power calculations showed that the analysed cohort represented by 410 LLIs and 553 young controls was sufficiently powered to replicate the association between rs978739 and the longevity phenotype according to the effect size and frequencies described in the previous paper, under a dominant and additive genetic model. However, no evidence of association between rs978739 and the longevity phenotype was observed according to the additive or dominant model. CONCLUSION: There are several reasons for the failure of the confirmation of a previous study. However, the differences between the two studies in terms of environment of the population adopted and of the criteria of inclusion have made difficult the replication of the findings.

7.
Immun Ageing ; 15: 26, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30450119

RESUMO

BACKGROUND: The aim of this study was to analyse the role of GM allotypes, i.e. the hereditary antigenic determinants expressed on immunoglobulin polypeptide chains, in the attainment of longevity. The role played by immunoglobulin allotypes in the control of immune responses is well known as well as the role of an efficient immune response in longevity achievement. So, it is conceivable that particular GM allotypes may contribute to the generation of an efficient immune response that supports successful ageing, hence longevity. METHODS: In order to show if GM allotypes play a role in the achievement of longevity, we typed the DNA of 95 Long-living individuals (LLIs) and 96 young control individuals (YCs) from South Italy for GM3/17 and GM23+/- alleles. RESULTS: To demonstrate the role of GM allotypes in the attainment of longevity we compared genotype and allele frequencies of GM allotypes between LLIs and YCs. A global chi-square test (3 × 2) shows that the distribution of genotypes at the GM 3/17 locus is highly significantly different in LLIs from that observed in YCs (p < 0.0001). The 2 × 2 chi-square test shows that the carriers of the GM3 allele contribute to this highly significant difference. Accordingly, GM3 allele is significantly overrepresented in LLIs. No significant differences were instead observed regarding GM23 allele. CONCLUSION: These preliminary results show that GM3 allotype is significantly overrepresented in LLIs. To best of our knowledge, this is the first study performed to assess the role of GM allotypes in longevity. So, it should be necessary to verify the data in a larger sample of individuals to confirm GM role in the attainment of longevity.

8.
Int J Mol Sci ; 19(10)2018 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-30347645

RESUMO

Evolutionary forces select genetic variants that allow adaptation to environmental stresses. The genomes of centenarian populations could recapitulate the evolutionary adaptation model and reveal the secrets of disease resistance shown by these individuals. Indeed, longevity phenotype is supposed to have a genetic background able to survive or escape to age-related diseases. Among these, cardiovascular diseases (CVDs) are the most lethal and their major risk factor is aging and the associated frailty status. One example of genetic evolution revealed by the study of centenarians genome is the four missense Single Nucleotide Polymorphisms (SNPs) haplotype in bactericidal/permeability-increasing fold-containing family B, member 4 (BPIFB4) locus that is enriched in long living individuals: the longevity associated variant (LAV). Indeed, LAV-BPIFB4 is able to improve endothelial function and revascularization through the increase of endothelial nitric oxide synthase (eNOS) dependent nitric oxide production. This review recapitulates the beneficial effects of LAV-BPIFB4 and its therapeutic potential for the treatment of CVDs.


Assuntos
Doenças Cardiovasculares/genética , Longevidade/genética , Fosfoproteínas/genética , Polimorfismo de Nucleotídeo Único , Seleção Genética , Evolução Molecular , Humanos , Peptídeos e Proteínas de Sinalização Intercelular
9.
Circ Res ; 117(4): 333-45, 2015 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-26034043

RESUMO

RATIONALE: Long living individuals show delay of aging, which is characterized by the progressive loss of cardiovascular homeostasis, along with reduced endothelial nitric oxide synthase activity, endothelial dysfunction, and impairment of tissue repair after ischemic injury. OBJECTIVE: Exploit genetic analysis of long living individuals to reveal master molecular regulators of physiological aging and new targets for treatment of cardiovascular disease. METHODS AND RESULTS: We show that the polymorphic variant rs2070325 (Ile229Val) in bactericidal/permeability-increasing fold-containing-family-B-member-4 (BPIFB4) associates with exceptional longevity, under a recessive genetic model, in 3 independent populations. Moreover, the expression of BPIFB4 is instrumental to maintenance of cellular and vascular homeostasis through regulation of protein synthesis. BPIFB4 phosphorylation/activation by protein-kinase-R-like endoplasmic reticulum kinase induces its complexing with 14-3-3 and heat shock protein 90, which is facilitated by the longevity-associated variant. In isolated vessels, BPIFB4 is upregulated by mechanical stress, and its knock-down inhibits endothelium-dependent vasorelaxation. In hypertensive rats and old mice, gene transfer of longevity-associated variant-BPIFB4 restores endothelial nitric oxide synthase signaling, rescues endothelial dysfunction, and reduces blood pressure levels. Furthermore, BPIFB4 is implicated in vascular repair. BPIFB4 is abundantly expressed in circulating CD34(+) cells of long living individuals, and its knock-down in endothelial progenitor cells precludes their capacity to migrate toward the chemoattractant SDF-1. In a murine model of peripheral ischemia, systemic gene therapy with longevity-associated variant-BPIFB4 promotes the recruitment of hematopoietic stem cells, reparative vascularization, and reperfusion of the ischemic muscle. CONCLUSIONS: Longevity-associated variant-BPIFB4 may represent a novel therapeutic tool to fight endothelial dysfunction and promote vascular reparative processes.


Assuntos
Células Progenitoras Endoteliais/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Longevidade/genética , Músculo Esquelético/irrigação sanguínea , Neovascularização Fisiológica , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteínas 14-3-3/metabolismo , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Animais , Pressão Sanguínea , Movimento Celular , Modelos Animais de Doenças , Europa (Continente) , Feminino , Estudos de Associação Genética , Terapia Genética , Genótipo , Células HEK293 , Proteínas de Choque Térmico HSP90/metabolismo , Membro Posterior , Humanos , Hipertensão/genética , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Hipertensão/terapia , Peptídeos e Proteínas de Sinalização Intercelular , Isquemia/genética , Isquemia/metabolismo , Isquemia/fisiopatologia , Isquemia/terapia , Masculino , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Óxido Nítrico Sintase Tipo III/metabolismo , Fenótipo , Fosforilação , Interferência de RNA , Ratos Endogâmicos SHR , Transdução de Sinais , Estresse Mecânico , Transfecção , Estados Unidos , Vasodilatação , eIF-2 Quinase/metabolismo
10.
Oral Health Prev Dent ; 15(3): 259-268, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28674706

RESUMO

PURPOSE: Systemic immune activation has been recently linked to chronic inflammatory disorders of the oral cavity, particularly to periodontitis. The purpose of this study was to determine whether treatment of a fungus-induced oral inflammation, namely denture-related stomatitis (DRS), can affect the activation of the systemic immune response. MATERIALS AND METHODS: Peripheral blood from patients with denture-related stomatitis caused by Candida albicans infection (n = 15) was collected at three time points: before treatment with nystatin, at the end of therapy and 2 months after finishing therapy. Activation of T cells and monocytes was assessed by flow cytometry. RESULTS: The percentages of peripheral lymphocytes, T cells and their subpopulations, as well as monocytes were similar before, immediately following and two months after nystatin treatment. Cells expressing early activation marker CD69 and RANTES C-C chemokine receptor type 5 significantly increased immediately after treatment and returned to baseline levels after two months. Th17 cells, which have been implicated in the pathogenesis of DRS, remained unchanged. Central memory CD4+ subset and intermediate subset of monocytes were lower after therapy and this effect was sustained for two months. CONCLUSION: Treatment of denture-related stomatitis does not seem to affect the general state of the cellular components of the immune system. The results suggest a potential proinflammatory effect of the antifungal agent, nystatin. Although transient and not intense, this effect might be of particular clinical importance, because of relationships between inflammation and certain diseases. Further studies are required to clarify this aspect.


Assuntos
Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candidíase Bucal/sangue , Candidíase Bucal/dietoterapia , Monócitos/efeitos dos fármacos , Nistatina/farmacologia , Nistatina/uso terapêutico , Estomatite sob Prótese/sangue , Estomatite sob Prótese/tratamento farmacológico , Linfócitos T/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estomatite sob Prótese/microbiologia
11.
J Prosthodont ; 26(1): 19-28, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26883670

RESUMO

PURPOSE: Chronic inflammatory disorders of the oral cavity, such as periodontitis, were recently linked to systemic immune activation. Since fungal oral infections have not yet been studied in this respect, the aim of our study is to determine whether the local inflammation caused by oral fungal infection of the palatal tissue (denture stomatitis-DS) is associated with the systemic inflammatory response. This question is becoming essential as the population ages. MATERIALS AND METHODS: Peripheral blood of DS patients (n = 20) and control patients (n = 24) was assessed with flow cytometry to determine lymphocyte and monocyte profiles. Intracellular cytometric analysis was carried out to establish cytokine production by T cells. DS was diagnosed based on clinical symptoms of DS such as swelling and redness of oral mucosa, confirmed by microbiological swabs for fungal colonization with Candida species. The control group was recruited from denture users without clinical and microbiological signs of oral infections. RESULTS: Percentages of peripheral lymphocytes, T cells, monocytes, and their subpopulations were similar in both studied groups. The exception was median percentages of CD25+ T cell subsets, which were significantly lower in DS patients than in control subjects. This reduction was observed in both CD4 T cell subset (16.7% and 28.1%; p = 0.0006) and CD8 T cell subset (4.6% and 7.0%; p = 0.007) CONCLUSIONS: While DS and associated local fungal infection do not overtly affect activation of monocytes or lymphocytes, the number of CD 25+ T cells is significantly lower in the DS patients, possibly indicating limited potential for the infection clearance in denture-using aging patients.


Assuntos
Subunidade alfa de Receptor de Interleucina-2/metabolismo , Estomatite sob Prótese/imunologia , Subpopulações de Linfócitos T/metabolismo , Idoso , Candidíase Bucal/imunologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estomatite sob Prótese/microbiologia , Subpopulações de Linfócitos T/imunologia
12.
Nucleic Acids Res ; 42(3): 2085-97, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24194608

RESUMO

Control over the simultaneous delivery of different functionalities and their synchronized intracellular activation can greatly benefit the fields of RNA and DNA biomedical nanotechnologies and allow for the production of nanoparticles and various switching devices with controllable functions. We present a system of multiple split functionalities embedded in the cognate pairs of RNA-DNA hybrids which are programmed to recognize each other, re-associate and form a DNA duplex while also releasing the split RNA fragments which upon association regain their original functions. Simultaneous activation of three different functionalities (RNAi, Förster resonance energy transfer and RNA aptamer) confirmed by multiple in vitro and cell culture experiments prove the concept. To automate the design process, a novel computational tool that differentiates between the thermodynamic stabilities of RNA-RNA, RNA-DNA and DNA-DNA duplexes was developed. Moreover, here we demonstrate that besides being easily produced by annealing synthetic RNAs and DNAs, the individual hybrids carrying longer RNAs can be produced by RNA polymerase II-dependent transcription of single-stranded DNA templates.


Assuntos
DNA/química , RNA/química , Aptâmeros de Nucleotídeos/química , Linhagem Celular Tumoral , Transferência Ressonante de Energia de Fluorescência , Humanos , Modelos Moleculares , Interferência de RNA , RNA Polimerase II/metabolismo , Termodinâmica , Transcrição Gênica
13.
BMC Genet ; 16: 15, 2015 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-25888430

RESUMO

BACKGROUND: Lone atrial flutter (AFL) and atrial fibrillation (AF) are common and sometimes consequential cardiac conduction disorders with a strong heritability, as underlined by recent genome-wide association studies that identified genetic modifiers. Follow-up family-based genetic analysis also identified Mendelian transmission of disease alleles. Three affected members were exome-sequenced for the identification of potential causative mutations, which were subsequently validated by direct sequencing in the other 3 affected members. Taqman assay was then used to confirm the role of any mutation in an independent population of sporadic lone AFL/AF cases. RESULTS: The family cluster analysis provided evidence of genetic inheritance of AFL in the family via autosomal dominant transmission. The exome-sequencing of 3 family members identified 7 potential mutations: of these, rs58238559, a rare missense genetic variant in the ATP-binding cassette sub-family B, member 4 (ABCB4) gene was carried by all affected members. Further analysis of 82 subjects with sporadic lone AF, 63 subjects with sporadic lone AFL, and 673 controls revealed that the allele frequency for this variation was significantly higher in cases than in the controls (0.05 vs. 0.01; OR = 3.73; 95% CI = 1.16-11.49; P = 0.013). CONCLUSIONS: rs58238559 in ABCB4 is a rare missense variant with a significant effect on the development of AFL/AF.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Fibrilação Atrial/genética , Flutter Atrial/genética , Mutação de Sentido Incorreto , Polimorfismo de Nucleotídeo Único , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , Exoma , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Linhagem
14.
Bioorg Med Chem ; 23(15): 4980-4988, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26043946

RESUMO

PABA/NO [O(2)-{2,4-dinitro-5-[4-(N-methylamino)benzoyloxy]phenyl} 1-(N,N-dimethylamino) diazen-1-ium-1,2-diolate] is a nitric oxide (NO)-releasing arylating agent designed to be selectively activated by reaction with glutathione (GSH) on catalysis by glutathione S-transferase P1 (GSTP1), an enzyme frequently overexpressed in cancer cells. PABA/NO has proven active in several cancer models in vitro and in vivo, but its tendency to be metabolized via a variety of pathways, some that generate inactive metabolites and hydrolysis products, limits its potential as a drug. Here we show that a simple replacement of cyano for nitro at the 4 position to give compound 4b ('p-cyano-PABA/NO') has the dual effect of slowing the undesired side reactions while enhancing the proportion of NO release and arylating activity on catalysis by GSTP1. Compound 4b showed increased resistance to hydrolysis and uncatalyzed reaction with GSH, along with a more favorable product distribution in the presence of GSTP1. It also showed significant proapoptotic activity. The data suggest p-cyano-PABA/NO to be a more promising prodrug than PABA/NO, with better selectivity toward cancer cells.


Assuntos
Ácido 4-Aminobenzoico/química , Glutationa S-Transferase pi/metabolismo , Óxido Nítrico/química , Ácido 4-Aminobenzoico/metabolismo , Ácido 4-Aminobenzoico/farmacologia , Biocatálise , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Glutationa/química , Glutationa/metabolismo , Glutationa S-Transferase pi/química , Células HL-60 , Humanos , Isomerismo , Cinética , Conformação Molecular , Óxido Nítrico/metabolismo , Óxido Nítrico/toxicidade
15.
Immun Ageing ; 12: 27, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26675039

RESUMO

BACKGROUND: People that reach extreme ages (Long-Living Individuals, LLIs) are object of intense investigation for increase/decrease of genetic variant frequencies, genetic methylation levels, protein abundance in serum and tissues. The aim of these studies is the discovery of the mechanisms behind LLIs extreme longevity and the identification of markers of well-being. We have recently associated a BPIFB4 haplotype (LAV) with exceptional longevity under a homozygous genetic model, and identified that CD34(+) of LLIs subjects express higher BPIFB4 transcript as compared to CD34(+) of control population. It would be of interest to correlate serum BPIFB4 protein levels with exceptional longevity and health status of LLIs. METHODS: Western blots on cellular medium to detect BPIFB4 secretion in transfected HEK293T cells with plasmid carrying BPIFB4 and ELISA on LLIs serum to detect BPIFB4 levels. RESULTS: Here we show that BPIFB4 is a secreted protein and its levels are increased in serum of LLIs, and high BPIFB4 levels classify their health status. CONCLUSIONS: Serum BPIFB4 protein levels classify longevity and health status in LLIs. Further studies are required to evaluate the possible role of BPIFB4 in monitoring disease progression.

16.
Nat Genet ; 38(8): 888-95, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16862160

RESUMO

We performed a whole-genome association analysis of lung tumor susceptibility using dense SNP maps ( approximately 1 SNP per 20 kb) in inbred mice. We reproduced the pulmonary adenoma susceptibility 1 (Pas1) locus identified in previous linkage studies and further narrowed this quantitative trait locus (QTL) to a region of less than 0.5 Mb in which at least two genes, Kras2 (Kirsten rat sarcoma oncogene 2) and Casc1 (cancer susceptibility candidate 1; also known as Las1), are strong candidates. Casc1 knockout mouse tumor bioassays showed that Casc1-deficient mice were susceptible to chemical induction of lung tumors. We also found three more genetic loci for lung adenoma development. Analysis of one of these candidate loci identified a previously uncharacterized gene Lasc1, bearing a nonsynonymous substitution (D102E). We found that the Lasc1 Glu102 allele preferentially promotes lung tumor cell growth. Our findings demonstrate the prospects for using dense SNP maps in laboratory mice to refine previous QTL regions and identify genetic determinants of complex traits.


Assuntos
Predisposição Genética para Doença , Neoplasias Pulmonares/genética , Adenoma/genética , Adenoma/patologia , Alelos , Animais , Mapeamento Cromossômico , Genoma , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos , Camundongos Knockout , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
17.
Immun Ageing ; 11(1): 19, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25469153

RESUMO

BACKGROUND: LMNA/C mutations have been linked to the premature aging syndrome Hutchinson's progeria, dilated cardiomyopathy 1A, skeletal myopathies (such as the autosomal dominant variant of Emery-Dreifuss muscular dystrophy and limb-girdle muscular dystrophy), Charcot-Marie-Tooth disorder type 2B1, mandibuloacral dysplasia, autosomal dominant partial lipodystrophy, and axonal neuropathy. Atrioventricular block (AVB) can be associated with several cardiac disorders and it can also be a highly heritable, primitive disease. One of the most common pathologies associated with AVB is dilated cardiomyopathy (DCM), which is characterized by cardiac dilatation and reduced systolic function. In this case, onset has been correlated with several mutations in genes essential for the proper maturation of cardiomyocytes, such as the gene for lamin A/C. However, no clear genotype-phenotype relationship has been reported to date between LMNA/C mutations and cardiomyopathies. RESULTS: DNA and medical histories were collected from (n = 11) members of different generations of one family, the proband of which was implanted with a pacemaker for lone, type II AVB. Exome sequencing analysis was performed on three relatives with AVB, and the mutations therein identified validated in a further three AVB-affected family members. In the initial three AVB family members, we identified 10 shared nonsynonymous single-nucleotide variations with a rare or unreported allele frequency in the 1000 Genomes Project database. Follow-up genetic screening in the additional three affected relatives disclosed a correlation between the lone AVB phenotype and the single-nucleotide polymorphism rs56816490, which generates an E317K change in lamin A/C. Although this mutation has already been described by others in a DCM-affected proband with familiarity for AVB and sudden death, the absence of DCM in our large, AVB-affected family is indicative of genotype-phenotype correlation between rs56816490 and a familial, autosomal dominant form of lone AVB. CONCLUSIONS: Screening for G613A in LMNA/C in patients with lone AVB and their relatives might prevent sudden death in families affected by AVB but without familiarity for DCM. Lone AVB is an age-related disease caused by mutations in LMNA/C gene rather than a complication of DCM.

18.
Methods Mol Biol ; 2797: 145-157, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38570458

RESUMO

MALDI-TOF mass spectrometry enables high-throughput screening of covalent fragment libraries and SAR compound progressions of selective KRAS G12C inhibitors. Using the MALDI-TOF platform instead of the more traditional ESI-MS TOF/orbitrap instrumentation can radically shorten sample acquisition time, allowing up to 384 samples to be screened in 30 min. The typical throughput for a covalent library screen is 1152 samples per 8 h, including processing, calculation, and reporting steps. The throughput can be doubled without any significant assay modification.


Assuntos
Ensaios de Triagem em Larga Escala , Proteínas Proto-Oncogênicas p21(ras) , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Proteínas Proto-Oncogênicas p21(ras)/genética , Ensaios de Triagem em Larga Escala/métodos , Mutação
19.
Br Dent J ; 236(12): 949-954, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38942856

RESUMO

As temporomandibular disorders (TMDs) become ever more prevalent in both primary and secondary care settings, successful management is increasingly challenging in both sectors. The authors aim to explore the dilemma of TMD management as the patient journeys through from primary to secondary care and offer educational tools to support practitioners in managing this complex patient cohort, as well as outlining alternative solutions for the delivery of TMD management strategies.


Assuntos
Transtornos da Articulação Temporomandibular , Humanos , Transtornos da Articulação Temporomandibular/terapia , Atenção Primária à Saúde , Atenção Secundária à Saúde
20.
Methods Mol Biol ; 2797: 271-285, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38570467

RESUMO

With recent advances proving that effective inhibition of KRAS is possible, there have been significant efforts made to develop inhibitors of specific mutant alleles. Here we describe a detailed protocol that employs homogeneous time-resolved fluorescence (HTRF) to identify compounds acting on KRAS signaling in malignant cell lines. This method allows for high-throughput, cell-based screens of large compound libraries for the development of RAS-targeted therapeutics.


Assuntos
Antineoplásicos , Proteínas Proto-Oncogênicas p21(ras) , Proteínas Proto-Oncogênicas p21(ras)/genética , Antineoplásicos/farmacologia , Linhagem Celular , Transdução de Sinais , Ensaios de Triagem em Larga Escala/métodos , Linhagem Celular Tumoral
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