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1.
BMC Med ; 22(1): 166, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38637816

RESUMO

BACKGROUND: The co-administration of drugs known to interact greatly impacts morbidity, mortality, and health economics. This study aims to examine the drug-drug interaction (DDI) phenomenon with a large-scale longitudinal analysis of age and gender differences found in drug administration data from three distinct healthcare systems. METHODS: This study analyzes drug administrations from population-wide electronic health records in Blumenau (Brazil; 133 K individuals), Catalonia (Spain; 5.5 M individuals), and Indianapolis (USA; 264 K individuals). The stratified prevalences of DDI for multiple severity levels per patient gender and age at the time of administration are computed, and null models are used to estimate the expected impact of polypharmacy on DDI prevalence. Finally, to study actionable strategies to reduce DDI prevalence, alternative polypharmacy regimens using drugs with fewer known interactions are simulated. RESULTS: A large prevalence of co-administration of drugs known to interact is found in all populations, affecting 12.51%, 12.12%, and 10.06% of individuals in Blumenau, Indianapolis, and Catalonia, respectively. Despite very different healthcare systems and drug availability, the increasing prevalence of DDI as patients age is very similar across all three populations and is not explained solely by higher co-administration rates in the elderly. In general, the prevalence of DDI is significantly higher in women - with the exception of men over 50 years old in Indianapolis. Finally, we show that using proton pump inhibitor alternatives to omeprazole (the drug involved in more co-administrations in Catalonia and Blumenau), the proportion of patients that are administered known DDI can be reduced by up to 21% in both Blumenau and Catalonia and 2% in Indianapolis. CONCLUSIONS: DDI administration has a high incidence in society, regardless of geographic, population, and healthcare management differences. Although DDI prevalence increases with age, our analysis points to a complex phenomenon that is much more prevalent than expected, suggesting comorbidities as key drivers of the increase. Furthermore, the gender differences observed in most age groups across populations are concerning in regard to gender equity in healthcare. Finally, our study exemplifies how electronic health records' analysis can lead to actionable interventions that significantly reduce the administration of known DDI and its associated human and economic costs.


Assuntos
Polimedicação , Masculino , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , Preparações Farmacêuticas , Prevalência , Interações Medicamentosas , Comorbidade
2.
medRxiv ; 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36798425

RESUMO

The co-administration of drugs known to interact has a high impact on morbidity, mortality, and health economics. We study the drug-drug interaction (DDI) phenomenon by analyzing drug administrations from population-wide Electronic Health Records (EHR) in Blumenau (Brazil), Catalonia (Spain), and Indianapolis (USA). Despite very different health care systems and drug availability, we find a common large risk of DDI administration that affected 13 to 20% of patients in these populations. In addition, the increasing risk of DDI as patients age is very similar across all three populations but is not explained solely by higher co-administration rates in the elderly. We also find that women are at higher risk of DDI overall- except for men over 50 years old in Indianapolis. Finally, we show that PPI alternatives to Omeprazole can reduce the number of patients affected by known DDIs by up to 21% in both Blumenau and Catalonia, and 2% in Indianapolis, exemplifying how analysis of EHR data can lead to a significant reduction of DDI and its associated human and economic costs. Although the risk of DDIs increases with age, administration patterns point to a complex phenomenon that cannot be solely explained by polypharmacy and multimorbidity. The lack of safer drug alternatives, particularly for chronic conditions, further overburdens health systems, thus highlighting the need for disruptive drug research.

3.
Clin Cancer Res ; 24(15): 3550-3559, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29588308

RESUMO

Purpose: Despite the wide use of antiangiogenic drugs in the clinical setting, predictive biomarkers of response to these drugs are still unknown.Experimental Design: We applied whole-exome sequencing of matched germline and basal plasma cell-free DNA samples (WES-cfDNA) on a RAS/BRAF/PIK3CA wild-type metastatic colorectal cancer patient with primary resistance to standard treatment regimens, including inhibitors to the VEGF:VEGFR2 pathway. We performed extensive functional experiments, including ectopic expression of VEGFR2 mutants in different cell lines, kinase and drug sensitivity assays, and cell- and patient-derived xenografts.Results: WES-cfDNA yielded a 77% concordance rate with tumor exome sequencing and enabled the identification of the KDR/VEGFR2 L840F clonal, somatic mutation as the cause of therapy refractoriness in our patient. In addition, we found that 1% to 3% of samples from cancer sequencing projects harbor KDR somatic mutations located in protein residues frequently mutated in other cancer-relevant kinases, such as EGFR, ABL1, and ALK. Our in vitro and in vivo functional assays confirmed that L840F causes strong resistance to antiangiogenic drugs, whereas the KDR hot-spot mutant R1032Q confers sensitivity to strong VEGFR2 inhibitors. Moreover, we showed that the D717V, G800D, G800R, L840F, G843D, S925F, R1022Q, R1032Q, and S1100F VEGFR2 mutants promote tumor growth in mice.Conclusions: Our study supports WES-cfDNA as a powerful platform for portraying the somatic mutation landscape of cancer and discovery of new resistance mechanisms to cancer therapies. Importantly, we discovered that VEGFR2 is somatically mutated across tumor types and that VEGFR2 mutants can be oncogenic and control sensitivity/resistance to antiangiogenic drugs. Clin Cancer Res; 24(15); 3550-9. ©2018 AACR.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Neoplasias Colorretais/genética , Neovascularização Patológica/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Quinase do Linfoma Anaplásico/genética , Inibidores da Angiogênese/efeitos adversos , Animais , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Ácidos Nucleicos Livres/sangue , Ácidos Nucleicos Livres/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias Colorretais/sangue , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Receptores ErbB/genética , Exoma/genética , Feminino , Xenoenxertos , Humanos , Camundongos , Mutação , Neovascularização Patológica/sangue , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Conformação Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-abl/genética , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/sangue , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/química , Sequenciamento do Exoma
4.
Elife ; 62017 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-28792888

RESUMO

SH2-containing-inositol-5-phosphatases (SHIPs) dephosphorylate the 5-phosphate of phosphatidylinositol-3,4,5-trisphosphate (PI(3,4,5)P3) and play important roles in regulating the PI3K/Akt pathway in physiology and disease. Aiming to uncover interdomain regulatory mechanisms in SHIP2, we determined crystal structures containing the 5-phosphatase and a proximal region adopting a C2 fold. This reveals an extensive interface between the two domains, which results in significant structural changes in the phosphatase domain. Both the phosphatase and C2 domains bind phosphatidylserine lipids, which likely helps to position the active site towards its substrate. Although located distant to the active site, the C2 domain greatly enhances catalytic turnover. Employing molecular dynamics, mutagenesis and cell biology, we identify two distinct allosteric signaling pathways, emanating from hydrophobic or polar interdomain interactions, differentially affecting lipid chain or headgroup moieties of PI(3,4,5)P3. Together, this study reveals details of multilayered C2-mediated effects important for SHIP2 activity and points towards interesting new possibilities for therapeutic interventions.


Assuntos
Fosfatos de Fosfatidilinositol/metabolismo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/química , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/metabolismo , Domínio Catalítico , Cristalografia por Raios X , Análise Mutacional de DNA , Humanos , Modelos Moleculares , Simulação de Dinâmica Molecular , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/genética , Fosfatidilserinas/metabolismo , Ligação Proteica , Conformação Proteica , Domínios Proteicos
5.
Biochemistry ; 55(41): 5854-5864, 2016 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-27682658

RESUMO

A 3,5-dihydro-5-methylidene-4H-imidazol-4-one (MIO) electrophilic moiety is post-translationally and autocatalytically generated in homotetrameric histidine ammonia-lyase (HAL) and other enzymes containing the tripeptide Ala-Ser-Gly in a suitably positioned loop. The backbone cyclization step is identical to that taking place during fluorophore formation in green fluorescent protein from the tripeptide Ser-Tyr-Gly, but dehydration, rather than dehydrogenation by molecular oxygen, is the reaction that gives rise to the mature MIO ring system. To gain additional insight into this unique process and shed light on some still unresolved issues, we have made use of extensive molecular dynamics simulations and hybrid quantum mechanics/molecular mechanics calculations implementing the self-consistent charge density functional tight-binding method on a fully solvated tetramer of Pseudomonas putida HAL. Our results strongly support the idea that mechanical compression of the reacting loop by neighboring protein residues in the precursor state is absolutely required to prevent formation of inhibitory main-chain hydrogen bonds and to enforce proper alignment of donor and acceptor orbitals for bond creation. The consideration of the protein environment in our computations shows that water molecules, which have been mostly neglected in previous theoretical work, play a highly relevant role in the reaction mechanism and, more importantly, that backbone cyclization resulting from the nucleophilic attack of the Gly amide lone pair on the π* orbital of the Ala carbonyl precedes side-chain dehydration of the central serine.


Assuntos
Histidina Amônia-Liase/metabolismo , Imidazóis/metabolismo , Cristalografia por Raios X , Histidina Amônia-Liase/química , Simulação de Dinâmica Molecular , Teoria Quântica
6.
J Med Chem ; 58(1): 237-51, 2015 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-25180654

RESUMO

A series of triazinic inhibitors of focal adhesion kinase (FAK) have been recently shown to exert antiangiogenic activity against HUVEC cells and anticancer efficacy against several cancer cell lines. We report herein that we further explored the heterocyclic core of these inhibitors by a fused imidazole ring with the triazine to provide imidazo[1,2-a][1,3,5]triazines. Importantly, these new compounds displayed 10(-7)-10(-8) M IC50 values, and the best inhibitor showed IC50 value of 50 nM against FAK enzymatic activity. Several inhibitors potently inhibited the proliferation of a panel of cancer cell lines expressing high levels of FAK. Apoptosis analysis in U87-MG and HCT-116 cell lines suggested that these compounds delayed cell cycle progression by arresting cells in the G2/M phase of the cell cycle, retarding cell growth. Further investigation demonstrated that these compounds strongly inhibited cell-matrix adhesion, migration, and invasion of U87-MG cells.


Assuntos
Antineoplásicos/farmacologia , Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Imidazóis/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Triazinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Desenho de Fármacos , Proteína-Tirosina Quinases de Adesão Focal/química , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Células HCT116 , Humanos , Imidazóis/síntese química , Imidazóis/química , Modelos Químicos , Modelos Moleculares , Estrutura Molecular , Fosforilação/efeitos dos fármacos , Ligação Proteica , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Estrutura Terciária de Proteína , Triazinas/síntese química , Triazinas/química
7.
Proc Natl Acad Sci U S A ; 111(31): E3177-86, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-25049397

RESUMO

Focal adhesion kinase (FAK) is a nonreceptor tyrosine kinase (NRTK) with key roles in integrating growth and cell matrix adhesion signals, and FAK is a major driver of invasion and metastasis in cancer. Cell adhesion via integrin receptors is well known to trigger FAK signaling, and many of the players involved are known; however, mechanistically, FAK activation is not understood. Here, using a multidisciplinary approach, including biochemical, biophysical, structural, computational, and cell biology approaches, we provide a detailed view of a multistep activation mechanism of FAK initiated by phosphatidylinositol-4,5-bisphosphate [PI(4,5)P2]. Interestingly, the mechanism differs from canonical NRTK activation and is tailored to the dual catalytic and scaffolding function of FAK. We find PI(4,5)P2 induces clustering of FAK on the lipid bilayer by binding a basic region in the regulatory 4.1, ezrin, radixin, moesin homology (FERM) domain. In these clusters, PI(4,5)P2 induces a partially open FAK conformation where the autophosphorylation site is exposed, facilitating efficient autophosphorylation and subsequent Src recruitment. However, PI(4,5)P2 does not release autoinhibitory interactions; rather, Src phosphorylation of the activation loop in FAK results in release of the FERM/kinase tether and full catalytic activation. We propose that PI(4,5)P2 and its generation in focal adhesions by the enzyme phosphatidylinositol 4-phosphate 5-kinase type Iγ are important in linking integrin signaling to FAK activation.


Assuntos
Proteína-Tirosina Quinases de Adesão Focal/química , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Fosfatidilinositol 4,5-Difosfato/farmacologia , Trifosfato de Adenosina/farmacologia , Regulação Alostérica/efeitos dos fármacos , Sequência de Aminoácidos , Aminoácidos/metabolismo , Biocatálise/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Análise por Conglomerados , Ativação Enzimática/efeitos dos fármacos , Transferência Ressonante de Energia de Fluorescência , Proteína-Tirosina Quinases de Adesão Focal/ultraestrutura , Técnicas de Silenciamento de Genes , Células HeLa , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Fosforilação/efeitos dos fármacos , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Ligação Proteica/efeitos dos fármacos , Estrutura Terciária de Proteína , Transdução de Sinais/efeitos dos fármacos , Quinases da Família src/metabolismo
8.
J Org Chem ; 76(5): 1452-5, 2011 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-21265527

RESUMO

Tris(trimethylsilyl)silane and azobis(cyclohexanenitrile) promoted the easy intramolecular arylation of aryl bromopyridine carbamates through a radical [1,6] ipso substitution process. These substrates showed a preference for this type of reaction over the alternative [1,7] addition. The results were rationalized by making use of quantum mechanical calculations and computer graphics.


Assuntos
Aminopiridinas/síntese química , Teoria Quântica , Aminopiridinas/química , Radicais Livres/química , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo
9.
Bioinformatics ; 26(14): 1804-5, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20501551

RESUMO

SUMMARY: Rapid expansion of available data about G Protein Coupled Receptor (GPCR) dimers/oligomers over the past few years requires an effective system to organize this information electronically. Based on an ontology derived from a community dialog involving colleagues using experimental and computational methodologies, we developed the GPCR-Oligomerization Knowledge Base (GPCR-OKB). GPCR-OKB is a system that supports browsing and searching for GPCR oligomer data. Such data were manually derived from the literature. While focused on GPCR oligomers, GPCR-OKB is seamlessly connected to GPCRDB, facilitating the correlation of information about GPCR protomers and oligomers. AVAILABILITY AND IMPLEMENTATION: The GPCR-OKB web application is freely available at http://www.gpcr-okb.org


Assuntos
Receptores Acoplados a Proteínas G/química , Software , Bases de Dados Factuais , Internet , Bases de Conhecimento
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