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1.
Mol Biol Evol ; 40(9)2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37695804

RESUMO

Uric acid is the main means of nitrogen excretion in uricotelic vertebrates (birds and reptiles) and the end product of purine catabolism in humans and a few other mammals. While uricase is inactivated in mammals unable to degrade urate, the presence of orthologous genes without inactivating mutations in avian and reptilian genomes is unexplained. Here we show that the Gallus gallus gene we name cysteine-rich urate oxidase (CRUOX) encodes a functional protein representing a unique case of cysteine enrichment in the evolution of vertebrate orthologous genes. CRUOX retains the ability to catalyze urate oxidation to hydrogen peroxide and 5-hydroxyisourate (HIU), albeit with a 100-fold reduced efficiency. However, differently from all uricases hitherto characterized, it can also facilitate urate regeneration from HIU, a catalytic property that we propose depends on its enrichment in cysteine residues. X-ray structural analysis highlights differences in the active site compared to known orthologs and suggests a mechanism for cysteine-mediated self-aggregation under H2O2-oxidative conditions. Cysteine enrichment was concurrent with the transition to uricotelism and a shift in gene expression from the liver to the skin where CRUOX is co-expressed with ß-keratins. Therefore, the loss of urate degradation in amniotes has followed opposite evolutionary trajectories: while uricase has been eliminated by pseudogenization in some mammals, it has been repurposed as a redox-sensitive enzyme in the reptilian skin.


Assuntos
Cisteína , Répteis , Pele , Urato Oxidase , Animais , Cisteína/genética , Peróxido de Hidrogênio , Pele/enzimologia , Urato Oxidase/genética , Urato Oxidase/metabolismo , Ácido Úrico , Galinhas/genética , Répteis/genética , Répteis/metabolismo
2.
Angew Chem Int Ed Engl ; 62(10): e202216309, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36622129

RESUMO

Propylene gas is produced worldwide by steam cracking on million-metric-ton scale per year. It serves as a valuable starting material for π-bond functionalization but is rarely applied in transition metal-catalyzed allylic C-H functionalization for fine chemical synthesis. Herein, we report that a newly-developed cationic cyclopentadienyliron dicarbonyl complex allows for the conversion of propylene to its allylic C-C bond coupling products under catalytic conditions. This approach was also found applicable to the allylic functionalization of simple α-olefins with distinctive branched selectivity. Experimental and computational mechanistic studies supported the allylic deprotonation of the metal-coordinated alkene as the turnover-limiting step and led to insights into the multifaceted roles of the newly designed ligand in promoting allylic C-H functionalization with enhanced reactivity and stereoselectivity.

3.
Ann Oncol ; 33(8): 814-823, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35513244

RESUMO

BACKGROUND: Difference in pathologic complete response (pCR) rate after neoadjuvant chemotherapy does not capture the impact of treatment on downstaging of residual cancer in the experimental arm. We developed a method to compare the entire distribution of residual cancer burden (RCB) values between clinical trial arms to better quantify the differences in cytotoxic efficacy of treatments. PATIENTS AND METHODS: The Treatment Efficacy Score (TES) reflects the area between the weighted cumulative distribution functions of RCB values from two trial arms. TES is based on a modified Kolmogorov-Smirnov test with added weight function to capture the importance of high RCB values and uses the area under the difference between two distribution functions as a statistical metric. The higher the TES the greater the shift to lower RCB values in the experimental arm. We developed TES from the durvalumab + olaparib arm (n = 72) and corresponding controls (n = 282) of the I-SPY2 trial. The 11 other experimental arms and control cohorts (n = 947) were used as validation sets to assess the performance of TES. We compared TES to Kolmogorov-Smirnov, Mann-Whitney, and Fisher's exact tests to identify trial arms with higher cytotoxic efficacy and assessed associations with trial arm level survival differences. Significance was assessed with a permutation test. RESULTS: In the validation set, TES identified arms with a higher pCR rate but was more accurate to identify regimens as less effective if treatment did not reduce the frequency of high RCB values, even if the pCR rate improved. The correlation between TES and survival was higher than the correlation between the pCR rate difference and survival. CONCLUSIONS: TES quantifies the difference between the entire distribution of pathologic responses observed in trial arms and could serve as a better early surrogate to predict trial arm level survival differences than pCR rate difference alone.


Assuntos
Antineoplásicos , Neoplasias da Mama , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/patologia , Feminino , Humanos , Terapia Neoadjuvante , Neoplasia Residual/tratamento farmacológico , Neoplasia Residual/patologia , Resultado do Tratamento
4.
Nat Ecol Evol ; 4(9): 1239-1246, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32601391

RESUMO

Among amniotes, reptiles and mammals are differently adapted to terrestrial life. It is generally appreciated that terrestrialization required adaptive changes of vertebrate metabolism, particularly in the mode of nitrogen excretion. However, the current paradigm is that metabolic adaptation to life on land did not involve synthesis of enzymatic pathways de novo, but rather repurposing of existing ones. Here, by comparing the inventory of pyridoxal 5'-phosphate-dependent enzymes in different amniotes, we identify in silico a pathway for sulfur metabolism present in chick embryos but not in mammals. Cysteine lyase contains haem and pyridoxal 5'-phosphate co-factors and converts cysteine and sulfite into cysteic acid and hydrogen sulfide, respectively. A specific cysteic acid decarboxylase produces taurine, while hydrogen sulfide is recycled into cysteine by cystathionine beta-synthase. This reaction sequence enables the formation of sulfonated amino acids during embryo development in the egg at no cost of reduced sulfur. The pathway originated around 300 million years ago in a proto-reptile by cystathionine beta-synthase duplication, cysteine lyase neofunctionalization and cysteic acid decarboxylase co-option. Our findings indicate that adaptation to terrestrial life involved innovations in metabolic pathways, and reveal the molecular mechanisms by which such innovations arose in amniote evolution.


Assuntos
Cistationina gama-Liase , Sulfeto de Hidrogênio , Animais , Embrião de Galinha , Cistationina beta-Sintase/genética , Cisteína , Enxofre
5.
Bone Joint J ; 101-B(11): 1392-1401, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31674241

RESUMO

AIMS: The aim of this study was to estimate the cost-effectiveness of negative-pressure wound therapy (NPWT) in comparison with standard wound management after initial surgical wound debridement in adults with severe open fractures of the lower limb. PATIENTS AND METHODS: An economic evaluation was conducted from the perspective of the United Kingdom NHS and Personal Social Services, based on evidence from the 460 participants in the Wound Management of Open Lower Limb Fractures (WOLLF) trial. Economic outcomes were collected prospectively over the 12-month follow-up period using trial case report forms and participant-completed questionnaires. Bivariate regression of costs (given in £, 2014 to 2015 prices) and quality-adjusted life-years (QALYs), with multiple imputation of missing data, was conducted to estimate the incremental cost per QALY gained associated with NPWT dressings. Sensitivity and subgroup analyses were undertaken to assess the impacts of uncertainty and heterogeneity, respectively, surrounding aspects of the economic evaluation. RESULTS: The base case analysis produced an incremental cost-effectiveness ratio of £267 910 per QALY gained, reflecting higher costs on average (£678; 95% confidence interval (CI) -£1082 to £2438) and only marginally higher QALYS (0.002; 95% CI -0.054 to 0.059) in the NPWT group. The probability that NPWT is cost-effective in this patient population did not exceed 27% regardless of the value of the cost-effectiveness threshold. This result remained robust to several sensitivity and subgroup analyses. CONCLUSION: This trial-based economic evaluation suggests that NPWT is unlikely to be a cost-effective strategy for improving outcomes in adult patients with severe open fractures of the lower limb. Cite this article: Bone Joint J 2019;101-B:1392-1401.


Assuntos
Ossos da Extremidade Inferior/lesões , Fraturas Expostas/economia , Tratamento de Ferimentos com Pressão Negativa/economia , Adolescente , Adulto , Idoso , Análise Custo-Benefício , Utilização de Instalações e Serviços , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Readmissão do Paciente/estatística & dados numéricos , Anos de Vida Ajustados por Qualidade de Vida , Reoperação/estatística & dados numéricos , Resultado do Tratamento , Adulto Jovem
6.
J Am Acad Orthop Surg ; 27(6): e293-e300, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30358636

RESUMO

BACKGROUND: Averaging length of stay (LOS) ignores patient complexity and is a poor metric for quality control in geriatric hip fracture programs. We developed a predictive model of LOS that compares patient complexity to the logistic effects of our institution's hip fracture care pathway. METHODS: A retrospective analysis was performed on patients enrolled into a hip fracture co-management pathway at an academic level I trauma center from 2014 to 2015. Patient complexity was approximated using the Charlson Comorbidity Index and ASA score. A predictive model of LOS was developed from patient-specific and system-specific variables using a multivariate linear regression analysis; it was tested against a sample of patients from 2016. RESULTS: LOS averaged 5.95 days. Avoidance of delirium and reduced time to surgery were found to be notable predictors of reduced LOS. The Charlson Comorbidity Index was not a strong predictor of LOS, but the ASA score was. Our predictive LOS model worked well for 63% of patients from the 2016 group; for those it did not work well for, 80% had postoperative complications. DISCUSSION: Predictive LOS modeling accounting for patient complexity was effective for identifying (1) reasons for outliers to the expected LOS and (2) effective measures to target for improving our hip fracture program. LEVEL OF EVIDENCE: III.


Assuntos
Avaliação Geriátrica/estatística & dados numéricos , Fraturas do Quadril/cirurgia , Tempo de Internação/estatística & dados numéricos , Modelos Estatísticos , Procedimentos Ortopédicos/estatística & dados numéricos , Idoso , Delírio/complicações , Delírio/epidemiologia , Feminino , Fraturas do Quadril/psicologia , Humanos , Escala de Gravidade do Ferimento , Modelos Lineares , Masculino , Análise Multivariada , Estudos Retrospectivos , Fatores de Tempo
7.
J Pain Res ; 11: 1343-1354, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30050318

RESUMO

BACKGROUND: Assessment of function and functional interference is an important component of chronic pain assessment and treatment and is commonly based on self-report questionnaires. Existing questionnaires for assessing functional interference are language dependent, which can limit their utility for patients across cultures with literacy, fluency, or cognitive restrictions. OBJECTIVE: The objectives of this study were to create a tool with minimal language dependence and literacy requirement for measuring functional interference due to chronic pain and evaluate the psychometric properties and usability of this new assessment scale, the Pictorial Pain Interference Questionnaire (PPIQ), in a clinical sample of participants with chronic pain. DESIGN: The study employed a prospective, cross-sectional design in a clinical chronic pain setting. PARTICIPANTS AND METHODS: A total of 113 participants with chronic non-cancer pain were recruited from a private chronic pain clinic. A pictorial scale was developed and tested via psychometric procedures, including comparisons with validated measures of functional interference and related chronic pain constructs. RESULTS: Excellent internal consistency reliability (a=0.91), good construct validity (total score: r=0.72-0.81), and adequate-to-good convergent and discriminant validities were demonstrated through comparative analyses with existing self-report questionnaires. A scoring metric for classifying low, moderate, and high levels of interference was found to have good construct validity. Evaluation of satisfaction revealed adequate understanding of the PPIQ among most users. CONCLUSION: Initial support for the PPIQ as an alternative to language-based questionnaires for assessing functional interference from chronic pain was found. Subsequent research will help to clarify psychometric properties of the PPIQ and user response among various chronic pain subgroups.

8.
J Phys Chem A ; 122(9): 2329-2343, 2018 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-29442510

RESUMO

(D3-)Methanol-nitrogen monoxide (CH3OH/CD3OH-NO) ices were exposed to ionizing radiation to facilitate the eventual determination of the CH3NO2 potential energy surface (PES) in the condensed phase. Reaction intermediates and products were monitored via infrared spectroscopy (FTIR) and photoionization reflectron time-of-flight mass spectrometry (PI-ReTOF-MS) during the irradiation and temperature controlled desorption (TPD) phase, respectively. Distinct photoionization energies were utilized to discriminate the isomer(s) formed in these processes. The primary methanol radiolysis products were the methoxy (CH3O) and hydroxymethyl (CH2OH) radicals along with atomic hydrogen. The former was found to react barrierlessly with nitrogen monoxide resulting in the formation of cis- and trans-methyl nitrite (CH3ONO), which is the most abundant product that can be observed in the irradiated samples. On the other hand, the self-recombination of hydroxymethyl radicals yielding ethylene glycol (HO(CH2)2OH) and glycerol (HOCH2CH2(OH)CH2OH) is preferred over the recombination with nitrogen monoxide to nitrosomethanol (HOCH2NO).

9.
J Bone Joint Surg Am ; 99(13): 1119-1128, 2017 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-28678125

RESUMO

BACKGROUND: We studied children and adolescents with symbrachydactyly to determine whether hand function depends on digit opposability and whether scores for function and quality-of-life measures differ from population norms. METHODS: Participants were grouped on the basis of hand morphology: Group A lacked opposable digits, and Group B had ≥2 digits that were opposable. The groups were compared with each other and with norms with respect to pinch strength, the performance of bimanual activities and in-hand manipulation, and questionnaires regarding psychosocial status and the ability to perform activities of daily living (ADLs). Participants and parents also rated the appearance and function of the hand. RESULTS: Pinch strength was higher for participants in Group B (4.1 compared with 2.4 kg; p = 0.008), but the groups did not differ with respect to the proportion of participants outside of pinch norms. Participants in Group B were more likely to actively use their affected hand to perform bimanual activities (p ≤ 0.0009), and to use normal or supination strategies to accomplish in-hand manipulation (p = 0.031). The groups did not differ in the proportion of ADLs rated "difficult" or "impossible," and both groups tested within normal limits for psychosocial function. Participants from both groups and their parents rated their satisfaction with hand appearance and function similarly high. CONCLUSIONS: Participants with ≥2 opposable digits incorporated their hand better in bimanual activities and used more effective strategies to accomplish in-hand manipulation than those who did not. These groups reported no difference in the ability to perform ADLs or with psychosocial function, which was within the normal range. Children and adolescents with symbrachydactyly demonstrated and reported a high level of function in all domains of validated function tests. This study provides information to help parents of children with a unilateral hand malformation understand their child's potential function, and assist surgeons with recommending treatment. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Avaliação da Deficiência , Deformidades Congênitas da Mão/fisiopatologia , Atividades Cotidianas , Adolescente , Criança , Estudos Transversais , Feminino , Deformidades Congênitas da Mão/psicologia , Força da Mão , Humanos , Masculino , Qualidade de Vida , Inquéritos e Questionários , Adulto Jovem
10.
Free Radic Biol Med ; 106: 62-68, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28189846

RESUMO

The cellular production of free radicals or reactive oxygen species (ROS) can lead to protein, lipid or DNA modifications and tumor formation. The cellular lipids undergo structural changes through the actions of enzymes (e.g. cyclooxygenases) or free radicals to form a class of compounds called Isolevuglandins (IsoLGs). The recruitment and continued exposure of tissue to ROS and IsoLGs causes increased cell proliferation, mutagenesis, loss of normal cell function and angiogenesis. The elevated concentration of ROS in cancerous tissues suggests that these mediators play an important role in cancer development. We hypothesized that tumors with elevated ROS levels would similarly possess an increased concentration of IsoLGs when compared with normal tissue. Using D11, an ScFv recombinant antibody specific for IsoLGs, we utilized immunohistochemistry to visualize the presence of IsoLG in human tumors compared to normal adjacent tissue (NAT) to the same tumor. We found that IsoLG concentrations were elevated in human breast, colon, kidney, liver, lung, pancreatic and tongue tumor cells when compared to NAT and believe that IsoLGs can be used as a gauge indicative of lipid peroxidation in tumors.


Assuntos
Carcinogênese/genética , Neoplasias/metabolismo , Estresse Oxidativo/genética , Prostaglandinas E/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Anticorpos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Radicais Livres/metabolismo , Humanos , Peroxidação de Lipídeos/genética , Neoplasias/genética , Neoplasias/patologia , Fosfolipídeos/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo
11.
Breast Cancer Res Treat ; 161(3): 567-574, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28005246

RESUMO

PURPOSE: Endoxifen concentrations have been associated with breast cancer recurrence in tamoxifen-treated patients. However, tamoxifen itself and other metabolites also show antiestrogenic anti-tumor activity. Therefore, the aim of this study was to develop a comprehensive Antiestrogenic Activity Score (AAS), which accounts for concentration and antiestrogenic activity of tamoxifen and three metabolites. An association between the AAS and recurrence-free survival was investigated and compared to a previously published threshold for endoxifen concentrations of 5.97 ng/mL. PATIENTS AND METHODS: The antiestrogenic activities of tamoxifen, (Z)-endoxifen, (Z)-4-hydroxytamoxifen, and N-desmethyltamoxifen were determined in a cell proliferation assay. The AAS was determined by calculating the sum of each metabolite concentration multiplied by an IC50 ratio, relative to tamoxifen. The AAS was calculated for 1370 patients with estrogen receptor alpha (ERα)-positive breast cancer. An association between AAS and recurrence was investigated using Cox regression and compared with the 5.97 ng/mL endoxifen threshold using concordance indices. RESULTS: An AAS threshold of 1798 was associated with recurrence-free survival, hazard ratio (HR) 0.67 (95% confidence interval (CI) 0.47-0.96), bias corrected after bootstrap HR 0.69 (95% CI 0.48-0.99). The concordance indices for AAS and endoxifen did not significantly differ; however, using the AAS threshold instead of endoxifen led to different dose recommendations for 5.2% of the patients. CONCLUSIONS: Endoxifen concentrations can serve as a proxy for the antiestrogenic effect of tamoxifen and metabolites. However, for the aggregate effect of tamoxifen and three metabolites, defined by an integrative algorithm, a trend towards improving treatment is seen and moreover, is significantly associated with breast cancer recurrence.


Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Antagonistas de Estrogênios/farmacologia , Tamoxifeno/farmacologia , Antineoplásicos Hormonais/metabolismo , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/epidemiologia , Relação Dose-Resposta a Droga , Antagonistas de Estrogênios/metabolismo , Antagonistas de Estrogênios/uso terapêutico , Feminino , Humanos , Concentração Inibidora 50 , Estimativa de Kaplan-Meier , Prognóstico , Modelos de Riscos Proporcionais , Tamoxifeno/metabolismo , Tamoxifeno/uso terapêutico , Resultado do Tratamento
12.
J Trauma Acute Care Surg ; 82(1): 133-137, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27602910

RESUMO

BACKGROUND: Computed tomography angiogram (CTA) is frequently utilized to detect vascular injuries even without examination findings indicating a vascular injury. We had the following hypotheses: (1) a CTA for lower extremity fractures with no clinical signs of a vascular injury is not indicated, and (2) fracture location and pattern would correlate with the risk of a vascular injury. METHODS: A retrospective review was conducted on patients who had an acute lower extremity fracture(s) and a CTA. Their charts were reviewed for multiple factors including the presence or absence of hard or soft signs of a vascular injury, soft tissue status, and fracture location/pattern. Every CTA radiology report was reviewed and any vascular intervention or amputation resulting from a vascular injury was recorded. Statistical analysis was performed. RESULTS: Of the 275 CTAs of fractured extremities reviewed, 80 (29%) had a positive CTA finding and 16 (6%) required treatment. A total of 109 (40%) of the extremities had no hard or soft signs; all had normal CTAs. Having at least one hard or soft sign was a significant risk factor for having a positive CTA. An open fracture, isolated proximal third fibula fracture, distal and shaft tibia fractures, and the presence of multiple fractures in one extremity were also associated with an increased risk for having a positive CTA. CONCLUSION: We found no evidence to support the routine use of CTAs to evaluate lower extremity fractures unless at least one hard or soft sign is present. The presence of an open fracture, distal tibia or tibial shaft fractures, multiple fractures in one extremity, and/or an isolated proximal third fibula fracture increases the risk of having a finding consistent with a vascular injury on a CTA. Only 6% of the cases required treatment, and all of them had diminished or absent distal pulses on presentation. LEVEL OF EVIDENCE: Diagnostic test, level III.


Assuntos
Angiografia por Tomografia Computadorizada , Fraturas Ósseas/diagnóstico por imagem , Traumatismos da Perna/diagnóstico por imagem , Lesões do Sistema Vascular/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Extremidade Inferior/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
13.
Vascul Pharmacol ; 86: 71-76, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27291140

RESUMO

Autoimmune rheumatic diseases are characterised by systemic inflammation and complex immunopathology, with an increased risk of cardiovascular disease, initiated by endothelial dysfunction in a chronic inflammatory environment. Endothelial microparticles (EMPs) are released into the circulation from activated endothelial cells and may therefore, reflect disease severity, vascular and endothelial dysfunction, that could influence disease pathogenesis via autocrine/paracrine signalling. The exact function of EMPs in rheumatic disease remains unknown, and this has initiated research to elucidate EMP composition and function, which may be determined by the mode of endothelial activation and the micro environment. To date, EMPs are thought to play a role in angiogenesis, thrombosis and inflammation by transferring specific proteins and microRNAs (miRs) to target cells. Here, we review the mechanisms underlying the generation and composition of EMPs and the clinical and experimental studies describing the involvement of EMPs in rheumatic diseases, since we have previously shown endothelial dysfunction and an elevated risk of cardiovascular disease are characteristics in systemic lupus erythematosus. We will also discuss the potential of EMPs as future biomarkers of cardiovascular risk in these diseases.


Assuntos
Doenças Autoimunes/fisiopatologia , Endotélio Vascular/metabolismo , Doenças Reumáticas/fisiopatologia , Animais , Doenças Autoimunes/imunologia , Biomarcadores/metabolismo , Doenças Cardiovasculares/imunologia , Doenças Cardiovasculares/fisiopatologia , Micropartículas Derivadas de Células/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Endotélio Vascular/patologia , Humanos , MicroRNAs/metabolismo , Doenças Reumáticas/imunologia , Fatores de Risco
14.
Oncogene ; 35(22): 2834-41, 2016 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-26455321

RESUMO

The loss of ß-catenin inhibitory components is a well-established mechanism of carcinogenesis but ß-catenin hyperactivity can also be enhanced through its coactivators. Here we first interrogated a highly validated genomic screen and the largest repository of cancer genomics data and identified JRK as a potential new oncogene and therapeutic target of the ß-catenin pathway. We proceeded to validate the oncogenic role of JRK in colon cancer cells and primary tumors. Consistent with a ß-catenin activator function, depletion of JRK in several cancer cell lines repressed ß-catenin transcriptional activity and reduced cell proliferation. Importantly, JRK expression was aberrantly elevated in 21% of colorectal cancers, 15% of breast and ovarian cancers and was associated with increased expression of ß-catenin target genes and increased cell proliferation. This study shows that JRK is required for ß-catenin hyperactivity regardless of the adenomatous polyposis coli/ß-catenin mutation status and targeting JRK presents new opportunities for therapeutic intervention in cancer.


Assuntos
Neoplasias da Mama/genética , Neoplasias do Colo/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Nucleares/metabolismo , Neoplasias Ovarianas/genética , Transcrição Gênica , beta Catenina/genética , Transporte Ativo do Núcleo Celular , Sequência de Bases , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Neoplasias do Colo/patologia , Simulação por Computador , Proteínas de Ligação a DNA , Feminino , Humanos , Mutação , Proteínas Nucleares/química , Proteínas Nucleares/genética , Oncogenes/genética , Neoplasias Ovarianas/patologia , Domínios Proteicos , Proteínas de Ligação a RNA , Regulação para Cima , Via de Sinalização Wnt/genética , beta Catenina/metabolismo
15.
BMC Plant Biol ; 15: 203, 2015 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-26276496

RESUMO

BACKGROUND: The mechanism by which plants synthesize and store high amounts of triacylglycerols (TAG) in tissues other than seeds is not well understood. The comprehension of controls for carbon partitioning and oil accumulation in nonseed tissues is essential to generate oil-rich biomass in perennial bioenergy crops. Persea americana (avocado), a basal angiosperm with unique features that are ancestral to most flowering plants, stores ~ 70 % TAG per dry weight in its mesocarp, a nonseed tissue. Transcriptome analyses of select pathways, from generation of pyruvate and leading up to TAG accumulation, in mesocarp tissues of avocado was conducted and compared with that of oil-rich monocot (oil palm) and dicot (rapeseed and castor) tissues to identify tissue- and species-specific regulation and biosynthesis of TAG in plants. RESULTS: RNA-Seq analyses of select lipid metabolic pathways of avocado mesocarp revealed patterns similar to that of other oil-rich species. However, only some predominant orthologs of the fatty acid biosynthetic pathway genes in this basal angiosperm were similar to those of monocots and dicots. The accumulation of TAG, rich in oleic acid, was associated with higher transcript levels for a putative stearoyl-ACP desaturase and endoplasmic reticulum (ER)-associated acyl-CoA synthetases, during fruit development. Gene expression levels for enzymes involved in terminal steps to TAG biosynthesis in the ER further indicated that both acyl-CoA-dependent and -independent mechanisms might play a role in TAG assembly, depending on the developmental stage of the fruit. Furthermore, in addition to the expression of an ortholog of WRINKLED1 (WRI1), a regulator of fatty acid biosynthesis, high transcript levels for WRI2-like and WRI3-like suggest a role for additional transcription factors in nonseed oil accumulation. Plastid pyruvate necessary for fatty acid synthesis is likely driven by the upregulation of genes involved in glycolysis and transport of its intermediates. Together, a comparative transcriptome analyses for storage oil biosynthesis in diverse plants and tissues suggested that several distinct and conserved features in this basal angiosperm species might contribute towards its rich TAG content. CONCLUSIONS: Our work represents a comprehensive transcriptome resource for a basal angiosperm species and provides insight into their lipid metabolism in mesocarp tissues. Furthermore, comparison of the transcriptome of oil-rich mesocarp of avocado, with oil-rich seed and nonseed tissues of monocot and dicot species, revealed lipid gene orthologs that are highly conserved during evolution. The orthologs that are distinctively expressed in oil-rich mesocarp tissues of this basal angiosperm, such as WRI2, ER-associated acyl-CoA synthetases, and lipid-droplet associated proteins were also identified. This study provides a foundation for future investigations to increase oil-content and has implications for metabolic engineering to enhance storage oil content in nonseed tissues of diverse species.


Assuntos
Regulação da Expressão Gênica de Plantas , Lipídeos/biossíntese , Persea/genética , Proteínas de Plantas/genética , RNA de Plantas/genética , Dados de Sequência Molecular , Persea/metabolismo , Proteínas de Plantas/metabolismo , RNA de Plantas/metabolismo , Sementes/metabolismo , Análise de Sequência de DNA , Transcriptoma
16.
Cell Cycle ; 14(13): 2121-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25950492

RESUMO

Fibroblast growth factor ligands and receptors (FGF and FGFR) play critical roles in tumorigenesis, and several drugs have been developed to target them. We report the biologic correlates of FGF/FGFR abnormalities in diverse malignancies. The medical records of patients with cancers that underwent targeted next generation sequencing (182 or 236 cancer-related genes) were reviewed. The following FGF/FGFR genes were tested: FGF3, 4, 6, 7, 10, 12, 14, 19, 23 and FGFR1, 2, 3, and 4. Of 391 patients, 56 (14.3%) had aberrant FGF (N = 38, all amplifications) and/or FGFR (N = 22 including 5 mutations and one FGFR3-TACC3 fusion). FGF/FGFR aberrations were most frequent in breast cancers (26/81, 32.1%, p = 0.0003). In multivariate analysis, FGF/FGFR abnormalities were independently associated with CCND1/2, RICTOR, ZNF703, RPTOR, AKT2, and CDK8 alterations (all P < 0.02), as well as with an increased median number of alterations (P < 0.0001). FGF3, FGF4, FGF19 and CCND1 were co-amplified in 22 of 391 patients (5.6%, P < 0.0001), most likely because they co-localize on the same chromosomal region (11q13). There was no significant difference in time to metastasis or overall survival when comparing patients harboring FGF/FGFR alterations versus those not. Overall, FGF/FGFR was one of the most frequently aberrant pathways in our population comprising patients with diverse malignancies. These aberrations frequently co-exist with anomalies in a variety of other genes, suggesting that tailored combination therapy may be necessary in these patients.


Assuntos
Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/genética , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transdução de Sinais/fisiologia
17.
Cancer Lett ; 340(2): 192-200, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23376639

RESUMO

Fusion genes are hybrid genes that combine parts of two or more original genes. They can form as a result of chromosomal rearrangements or abnormal transcription, and have been shown to act as drivers of malignant transformation and progression in many human cancers. The biological significance of fusion genes together with their specificity to cancer cells has made them into excellent targets for molecular therapy. Fusion genes are also used as diagnostic and prognostic markers to confirm cancer diagnosis and monitor response to molecular therapies. High-throughput sequencing has enabled the systematic discovery of fusion genes in a wide variety of cancer types. In this review, we describe the history of fusion genes in cancer and the ways in which fusion genes form and affect cellular function. We also describe computational methodologies for detecting fusion genes from high-throughput sequencing experiments, and the most common sources of error that lead to false discovery of fusion genes.


Assuntos
Biomarcadores Tumorais/genética , Fusão Gênica , Genoma Humano , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias/genética , Análise de Sequência de DNA , Animais , Biologia Computacional , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Testes Genéticos , Humanos , Neoplasias/diagnóstico , Neoplasias/terapia , Fenótipo , Medicina de Precisão , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes
18.
PLoS One ; 7(7): e41574, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22844503

RESUMO

BACKGROUND: Recently, MicroRNAs (miR) and AMP-kinase (AMPK) have emerged as prominent players in the development of cardiac hypertrophy and heart failure. We hypothesized that components of the adenosine monophosphate-activated kinase (AMPK) pathway are targeted by miRs and alter AMPK signaling during pathological cardiac stress. METHODOLOGY/PRINCIPAL FINDINGS: Using a mouse model of hypertrophic cardiomyopathy (HCM), we demonstrated early elevation of miR-195 and miR-451 in HCM hearts, which targets MO25, a central component of the MO25/STRAD/LKB1 complex that acts as an upstream kinase for AMPK. We show functional targeting of MO25 by miR-195 and -451. Further in vitro interrogation of MO25 as a functional target validated this hypothesis where over-expression of miR-195 in C2C12 cells knocked down MO25 expression levels and downstream AMPK signaling (phosphorylation of Acetyl CoA carboxylase [ACC] and AMPK activity assay), similar to MO25 knockdown in C2C12 cells by siRNA. Parallel changes were measured in 60 day R403Q HCM male hearts that were rescued by short-term administration of AICAR, an AMPK agonist. CONCLUSIONS/SIGNIFICANCE: Elevated miR-195 targets the LKB1/AMPK signaling axis in HCM progression and implicates a functional role in HCM disease progression. MiR-195 may serve as potential therapeutics or therapeutic targets for heart disease.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adenilato Quinase/metabolismo , MicroRNAs/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/genética , Proteínas Quinases Ativadas por AMP , Animais , Sequência de Bases , Proteínas de Ligação ao Cálcio , Cardiomiopatia Hipertrófica/tratamento farmacológico , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/metabolismo , Cardiomiopatia Hipertrófica/patologia , Linhagem Celular , Progressão da Doença , Ativação Enzimática/genética , Humanos , Masculino , Camundongos , MicroRNAs/genética , Terapia de Alvo Molecular , Miocárdio/metabolismo , Miocárdio/patologia , Especificidade de Órgãos , Regulação para Cima/genética
19.
Br J Pharmacol ; 164(7): 1829-44, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21557737

RESUMO

BACKGROUND AND PURPOSE: Opioid use and abuse has been linked to significant immunosuppression, which has been attributed, in part, to drug-induced depletion of lymphocytes. We sought to define the mechanisms by which lymphocyte populations are depleted and recover following morphine treatment in mice. EXPERIMENTAL APPROACH: Mice were implanted with morphine pellets and B- and T-cell subsets in the bone marrow, thymus, spleen and lymph nodes were analysed at various time points. We also examined the effects of morphine on T-cell development using an ex vivo assay. KEY RESULTS: The lymphocyte populations most susceptible to morphine-induced depletion were the precursor cells undergoing selection. As the lymphocytes recovered, more lymphocyte precursors proliferated than in control mice. In addition, peripheral T-cells displayed evidence that they had undergone homeostatic proliferation during the recovery phase of the experiments. CONCLUSIONS AND IMPLICATIONS: The recovery of lymphocytes following morphine-induced depletion occurred in the presence of morphine and via increased proliferation of lymphoid precursors and homeostatic proliferation of T-cells.


Assuntos
Analgésicos Opioides/farmacologia , Linfócitos B/efeitos dos fármacos , Morfina/farmacologia , Entorpecentes/farmacologia , Linfócitos T/efeitos dos fármacos , Animais , Linfócitos B/imunologia , Medula Óssea/efeitos dos fármacos , Medula Óssea/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Corticosterona/sangue , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Contagem de Linfócitos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Baço/efeitos dos fármacos , Baço/imunologia , Linfócitos T/imunologia , Timo/efeitos dos fármacos , Timo/imunologia
20.
Clin Pharmacol Ther ; 89(5): 718-25, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21430657

RESUMO

We explored whether breast cancer outcomes are associated with endoxifen and other metabolites of tamoxifen and examined potential correlates of endoxifen concentration levels in serum including cytochrome P450 2D6 (CYP2D6) metabolizer phenotype and body mass index (BMI). Concentration levels of tamoxifen, endoxifen, 4-hydroxytamoxifen (4OH-tamoxifen), and N-desmethyltamoxifen (ND-tamoxifen) were measured from samples taken from 1,370 patients with estrogen receptor (ER)-positive breast cancer who were participating in the Women's Healthy Eating and Living (WHEL) Study. We tested these concentration levels for possible associations with breast cancer outcomes and found that breast cancer outcomes were not associated with the concentration levels of tamoxifen, 4-hydroxytamoxifen, and ND-tamoxifen. For endoxifen, a threshold was identified, with women in the upper four quintiles of endoxifen concentration appearing to have a 26% lower recurrence rate than women in the bottom quintile (hazard ratio (HR) = 0.74; 95% confidence interval (CI), (0.55-1.00)). The predictors of this higher-risk bottom quintile were poor/intermediate metabolizer genotype, higher BMI, and lower tamoxifen concentrations as compared with the mean for the cohort as a whole. This study suggests that there is a minimal concentration threshold above which endoxifen is effective against the recurrence of breast cancer and that ~80% of tamoxifen takers attain this threshold.


Assuntos
Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Citocromo P-450 CYP2D6/genética , Tamoxifeno/análogos & derivados , Tamoxifeno/metabolismo , Neoplasias da Mama/tratamento farmacológico , Estudos de Coortes , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Fenótipo , Tamoxifeno/sangue , Tamoxifeno/uso terapêutico , Resultado do Tratamento
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