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1.
Forensic Sci Int ; 332: 111175, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35026699

RESUMO

Hand-held, portable X-Ray fluorescence instruments (pXRF) provide a means of rapid, in-situ chemical characterisation that has considerable application as a rapid trace evidence characterisation tool in forensic geoscience. This study presents both a control test study which demonstrates optimisation of the data collection process, alongside a range of individual forensic case studies, including heavy metal contamination, conflict archaeology, forensic soil characterisation, and verification of human remains, which together validate the technique and provide some comparison between field-based and laboratory-based pXRF applications. Results highlight the time-efficiency and cost-effectiveness of in-situ, field-based pXRF analyses for material characterisation when compared with other trace evidence methods. Analytical precision of various analytes during in-situ analysis was sufficient to demonstrate considerable application of field-based pXRF as a tool for rapid identification of specific areas of interest to be further investigated. Laboratory-based pXRF analyses yielded greater accuracy which could provide an efficient compromise between field-based pXRF and traditional laboratory-based analytical techniques (e.g. WD-XRF, ICP-MS). Further studies should collect more advanced datasets in more diverse locations to further validate the techniques capability to rapidly conduct geochemical surveys in a range of environments.


Assuntos
Ciências Forenses/instrumentação , Poluentes do Solo , Espectrometria por Raios X/instrumentação , Crime , Ciências da Terra , Humanos , Poluentes do Solo/análise
2.
Dis Model Mech ; 15(2)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34779486

RESUMO

Anti-cancer properties of statins are controversial and possibly context dependent. Recent pathology/epidemiology studies of human lung adenocarcinoma showed reduced pro-tumourigenic macrophages associated with a shift to lower-grade tumours amongst statin users but, paradoxically, worse survival compared with that of non-users. To investigate the mechanisms involved, we have characterised mouse lung adenoma/adenocarcinoma models treated with atorvastatin. Here, we show that atorvastatin suppresses premalignant disease by inhibiting the recruitment of pro-tumourigenic macrophages to the tumour microenvironment, manifested in part by suppression of Rac-mediated CCR1 ligand secretion. However, prolonged atorvastatin treatment leads to drug resistance and progression of lung adenomas into invasive disease. Pathological progression is not driven by acquisition of additional driver mutations or immunoediting/evasion but is associated with stromal changes including the development of desmoplastic stroma containing Gr1+ myeloid cells and tertiary lymphoid structures. These findings show that any chemopreventive functions of atorvastatin in lung adenocarcinoma are overridden by stromal remodelling in the long term, thus providing mechanistic insight into the poor survival of lung adenocarcinoma patients with statin use.


Assuntos
Adenocarcinoma de Pulmão , Inibidores de Hidroximetilglutaril-CoA Redutases , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/tratamento farmacológico , Animais , Atorvastatina/farmacologia , Atorvastatina/uso terapêutico , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Neoplasias Pulmonares/patologia , Camundongos , Microambiente Tumoral
3.
Lab Invest ; 101(3): 396-407, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33318618

RESUMO

Patient-derived explants (PDEs) represent the direct culture of fragments of freshly-resected tumour tissue under conditions that retain the original architecture of the tumour. PDEs have advantages over other preclinical cancer models as platforms for predicting patient-relevant drug responses in that they preserve the tumour microenvironment and tumour heterogeneity. At endpoint, PDEs may either be processed for generation of histological sections or homogenised and processed for 'omic' evaluation of biomarker expression. A significant advantage of spatial profiling is the ability to co-register drug responses with tumour pathology, tumour heterogeneity and changes in the tumour microenvironment. Spatial profiling of PDEs relies on the utilisation of robust immunostaining approaches for validated biomarkers and incorporation of appropriate image analysis methods to quantitatively and qualitatively monitor changes in biomarker expression in response to anti-cancer drugs. Automation of immunostaining and image analysis would provide a significant advantage for the drug discovery pipeline and therefore, here, we have sought to optimise digital pathology approaches. We compare three image analysis software platforms (QuPath, ImmunoRatio and VisioPharm) for evaluating Ki67 as a marker for proliferation, cleaved PARP (cPARP) as a marker for apoptosis and pan-cytokeratin (CK) as a marker for tumour areas and find that all three generate comparable data to the views of a histomorphometrist. We also show that Virtual Double Staining of sequential sections by immunohistochemistry results in imperfect section alignment such that CK-stained tumour areas are over-estimated. Finally, we demonstrate that multi-immunofluorescence combined with digital image analysis is a superior method for monitoring multiple biomarkers simultaneously in tumour and stromal areas in PDEs.


Assuntos
Antineoplásicos/uso terapêutico , Monitoramento de Medicamentos/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imuno-Histoquímica/métodos , Neoplasias , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Biologia Computacional , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Células Tumorais Cultivadas
4.
Gynecol Oncol ; 160(2): 557-567, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33309417

RESUMO

OBJECTIVE: To undertake a pilot study to develop a novel Patient-Derived-Explant (PDE) model system for use in endometrial cancer (EC) that is capable of monitoring differential drug responses in a pre-clinical setting. METHODS: Fresh tumour was obtained post-hysterectomy from 27 patients with EC. Tumours were cut into 1-3 mm3 explants that were cultured at the air-liquid interface for 16-24 h in culture media. Explants were cultured in different media conditions to optimise viability. Explants were also treated with carboplatin/paclitaxel or pembrolizumab for 24 h and processed into histology slides. Multiplexed immunofluorescence for Ki67 (proliferation marker), cPARP (apoptosis marker) and CAM 5.2 (tumour mask) was performed followed by image analysis and quantitation of biomarker expression. RESULTS: EC samples are amenable to PDE culture with preserved histological architecture and PDE viability for up to 48 h, with the addition of autologous serum in culture media facilitating EC-PDE viability. Our PDE platform provides evidence of differential drug-response to conventional chemotherapeutics and immune checkpoint inhibition, and these responses can be assessed in the context of a preserved tumour microenvironment. CONCLUSIONS: Our PDE platform represents a rapid, low-cost pre-clinical model which can be easily integrated into drug development pipelines. PDE culture preserves original tumour architecture and enables evaluation of spatial relationships in the tumour microenvironment. PDE culture has the potential for personalised drug-testing in a pre-clinical setting which is increasingly important in an era of personalised medicine in the treatment of EC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias do Endométrio/terapia , Endométrio/patologia , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Carboplatina/farmacologia , Carboplatina/uso terapêutico , Quimioterapia Adjuvante/métodos , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/imunologia , Neoplasias do Endométrio/patologia , Endométrio/cirurgia , Estudos de Viabilidade , Feminino , Heterogeneidade Genética , Humanos , Histerectomia , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Projetos Piloto , Medicina de Precisão/métodos , Técnicas de Cultura de Tecidos , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
5.
Anal Chem ; 92(14): 9847-9855, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32545955

RESUMO

The use of a low aerosol dispersion ablation chamber within a laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS) setup allows for high-resolution, high-speed imaging of the distribution of elements within a sample. Here we show how this enhanced capability creates new analytical problems and solutions. We report the distribution of platinum at the cellular level in non-small cell lung cancer (NSCLC) explant models after treatment with clinically relevant doses of cisplatin. This revealed for the first time a correlation between the platinum signal and the presence of carbon deposits within lung tissue. We show how complementary ion beam analysis techniques, particle-induced X-ray emission (PIXE) and elastic backscattering spectrometry (EBS), can be used to explore potential matrix effects in LA-ICP-MS data. For these samples, it was confirmed that the enhancement was unlikely to have resulted from a matrix effect alone. Thus, the presence of carbon deposits within tissue has potential implications for the effective distribution of the cisplatin drug.


Assuntos
Cisplatino/uso terapêutico , Neoplasias Pulmonares/química , Neoplasias Pulmonares/tratamento farmacológico , Espectrometria de Massas/métodos , Antineoplásicos/uso terapêutico , Carbono/química , Carcinoma Pulmonar de Células não Pequenas , Humanos , Terapia a Laser , Esferoides Celulares , Técnicas de Cultura de Tecidos
6.
Vet J ; 246: 66-70, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30902191

RESUMO

After strangles outbreaks, Streptococcus equi ssp. equi (S. equi) can persist in clinically normal silent carriers for months to years. Two naturally occurring outbreaks of strangles with 53 and 100% morbidity, respectively, were followed longitudinally to assess occurrence of carrier state and optimal detection methods Outbreak A involved 98 yearling warmbloods, and outbreak B 38 mature Icelandic horses. Fully recovered horses were sampled at least 6 months after index cases using nasal swabs (one sampling occasion only) nasopharyngeal lavage and guttural pouch visualisation and lavages for culture and qPCR to S. equi. Any horse with at least a single sample positive was deemed a carrier. Descriptive statistics and sensitivity and negative predictive values were calculated. Comparisons were made with McNemars and Fishers exact tests. Carrier rates in outbreak A were 3% based on culture and 15% based on qPCR and for outbreak B 13% based on culture and 37% based on qPCR. All culture positives were also qPCR positive. One carrier culture negative sampled after an additional 8 months was culture positive to S. equi, indicating that qPCR positives should be suspected to carry live bacteria. Findings indicate that reliance on guttural pouch sampling and appearance does not capture all silent carriers. All culture positives were identified by qPCR and even horses positive by qPCR but culture negative should be suspected carriers of live bacteria.


Assuntos
Portador Sadio/veterinária , Orelha Média/microbiologia , Doenças dos Cavalos/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Infecções Estreptocócicas/veterinária , Streptococcus equi/isolamento & purificação , Animais , Portador Sadio/diagnóstico , Portador Sadio/epidemiologia , Surtos de Doenças/veterinária , Feminino , Doenças dos Cavalos/microbiologia , Cavalos , Estudos Longitudinais , Masculino , Lavagem Nasal/veterinária , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/epidemiologia , Streptococcus equi/crescimento & desenvolvimento
7.
Breast Cancer Res ; 20(1): 80, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30068377

RESUMO

After the publication of this work [1] an error was noticed in Fig. 6 (b). In the MCF-7/Vector columns, the same image was used accidentally for the 0 h and 24 h time points. Both images were taken from the 0 h time point.

8.
J Vet Intern Med ; 32(1): 459-464, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29377359

RESUMO

BACKGROUND: Streptococcus equi ssp. equi causes characteristic clinical signs that are most severe in young horses, including fever, purulent nasal discharge, and lymph node abscessation in the head region. HYPOTHESIS/OBJECTIVES: Clinical, serologic, and microbiologic factors related to unexpectedly mild disease severity in a natural outbreak of strangles in immunologically naïve weanlings were investigated. ANIMALS: One-hundred and twelve warmblood weanlings. METHODS: Prospective longitudinal observational study of a natural outbreak of strangles. The entire cohort was examined at the peak of the outbreak by deep nasal swabs for culture and quantitative PCR (qPCR) for the presence of S. equi and clinically and serologically in a sequential manner by an optimized ELISA from the index case throughout the outbreak until resolution. Descriptive statistics were calculated and comparisons made using a nondirectional Wilcoxon signed-rank test. RESULTS: Outbreak morbidity was 53%, with 9 of 14 horses culture positive and 26 of 53 horses qPCR positive for S. equi lacking clinical signs characteristic of strangles. By resolution, 91 of 112 had seroconverted to Antigen A by ELISA but seroconversion to antigen C (part of the SeM protein) was minimal. Sequencing of the isolates detected no alterations in the SeM protein, but identified a 61 bp deletion in the gene SEQ_0402. CONCLUSIONS AND CLINICAL IMPORTANCE: Absence of clinical signs alone in naïve horses may be an insufficient criterion to release horses from strangles quarantine measures. Restricted seroconversion to antigen C may have been associated with decreased clinical severity. The role of a minor gene deletion in SEQ_0402 in the virulence of S. equi warrants further investigation.


Assuntos
Doenças dos Cavalos/microbiologia , Soroconversão , Infecções Estreptocócicas/veterinária , Streptococcus equi/isolamento & purificação , Animais , Surtos de Doenças/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Doenças dos Cavalos/imunologia , Cavalos , Masculino , Cavidade Nasal/microbiologia , Reação em Cadeia da Polimerase/veterinária , Estudos Prospectivos , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/microbiologia , Streptococcus equi/genética , Streptococcus equi/imunologia
9.
Oncotarget ; 8(50): 87221-87233, 2017 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-29152076

RESUMO

The majority of pancreatic ductal adenocarcinomas (PDAC) are diagnosed late so that surgery is rarely curative. Earlier detection could significantly increase the likelihood of successful treatment and improve survival. The aim of the study was to provide proof of principle that point mutations in key cancer genes can be identified by sequencing circulating free DNA (cfDNA) and that this could be used to detect early PDACs and potentially, premalignant lesions, to help target early effective treatment. Targeted next generation sequencing (tNGS) analysis of mutation hotspots in 50 cancer genes was conducted in 26 patients with PDAC, 14 patients with chronic pancreatitis (CP) and 12 healthy controls with KRAS status validated by digital droplet PCR. A higher median level of total cfDNA was observed in patients with PDAC (585 ng/ml) compared to either patients with CP (300 ng/ml) or healthy controls (175 ng/ml). PDAC tissue showed wide mutational heterogeneity, whereas KRAS was the most commonly mutated gene in cfDNA of patients with PDAC and was significantly associated with a poor disease specific survival (p=0.018). This study demonstrates that tNGS of cfDNA is feasible to characterise the circulating genomic profile in PDAC and that driver mutations in KRAS have prognostic value but cannot currently be used to detect early emergence of disease. Importantly, monitoring total cfDNA levels may have utility in individuals "at risk" and warrants further investigation.

10.
Oncogene ; 36(47): 6640-6648, 2017 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-28783176

RESUMO

Two proteins comprising the ZEB family of zinc finger transcription factors, ZEB1 and ZEB2, execute EMT programs in embryonic development and cancer. By studying regulation of their expression, we describe a novel mechanism that limits ZEB2 protein synthesis. A protein motif located at the border of the SMAD-binding domain of ZEB2 protein induces ribosomal pausing and compromises protein synthesis. The function of this protein motif is dependent on stretches of rare codons, Leu(UUA)-Gly(GGU)-Val(GUA). Incorporation of these triplets in the homologous region of ZEB1 does not affect protein translation. Our data suggest that rare codons have a regulatory role only if they are present within appropriate protein structures. We speculate that pools of transfer RNA available for protein translation impact on the configuration of epithelial mesenchymal transition pathways in tumor cells.


Assuntos
Códon/genética , Neoplasias/metabolismo , Biossíntese de Proteínas/genética , RNA de Transferência de Glicina/metabolismo , RNA de Transferência de Leucina/metabolismo , RNA de Transferência de Valina/metabolismo , Homeobox 2 de Ligação a E-box com Dedos de Zinco/metabolismo , Motivos de Aminoácidos/genética , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Glicina/genética , Humanos , Leucina/genética , Transdução de Sinais , Valina/genética , Homeobox 2 de Ligação a E-box com Dedos de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo
11.
Chem Commun (Camb) ; 53(47): 6288-6302, 2017 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-28534592

RESUMO

Thermo-electrochemical cells (also called thermocells) are promising devices for harvesting waste heat for the sustainable production of energy. Research into thermocells has increased significantly in recent years, driven by advantages such as their ability to continuously convert heat into electrical energy without producing emissions or consuming materials. Until relatively recently, the commercial viability of thermocells was limited by their low power output and conversion efficiency. However, there have lately been significant advances in thermocell performance as a result of improvements to the electrode materials, electrolyte and redox chemistry and various features of the cell design. This article overviews these recent developments in thermocell research, including the development of new redox couples, the optimisation of electrolytes for improved power output and high-temperature operation, the design of high surface area electrodes for increased current density and device flexibility, and the optimisation of cell design to further enhance performance.

12.
Mod Pathol ; 30(1): 60-68, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27713424

RESUMO

Outcomes for melanoma patients vary within cancer stage. Prognostic biomarkers are potential adjuncts to provide more precise prognostic information. Simple, low-cost biomarker assays, such as those based on immunohistochemistry, have strong translational potential. 5-hydroxymethylcytosine (5 hmC) shows prognostic potential in melanoma but prior studies were small. We, therefore, analysed 5 hmC in a retrospective cohort to provide external validation of its prognostic value. Two hundred primary melanomas were evaluated for 5 hmC expression using immunohistochemistry. The primary objective was to assess the effect on overall survival while controlling for important confounders. Univariable and multivariable analyses were performed. REMARK guidelines were followed. The 5 hmC immunohistochemistry scoring showed very strong inter-observer agreement (ICC 0.88) and expression was significantly related to age, site, Breslow thickness, ulceration, mitotic rate, and stage. Kaplan-Meier analysis showed 5 hmC was associated with metastasis-free, melanoma-specific, and overall survival, P<0.0001 for each. In univariable Cox proportional hazards models, 5 hmC hazard ratios were significant and remained so in a multivariable model. A two-step cox model was created using stage and 5 hmC, as stage is the gold standard for clinical practice. The addition of 5 hmC produced significant improvement in the model and 5 hmC and stage were independent significant predictors. This is the largest study of the prognostic value of 5 hmC immunohistochemistry in melanoma. The 5 hmC scoring was easily and reproducibly performed and it was an independent predictor of metastasis-free survival, melanoma-specific survival, and overall survival. This work supports further development of 5 hmC as a prognostic biomarker and suggests that it could add more precision to American Joint Committee on Cancer staging.


Assuntos
5-Metilcitosina/análogos & derivados , Melanoma/metabolismo , Neoplasias Cutâneas/metabolismo , Pele/metabolismo , 5-Metilcitosina/metabolismo , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Melanoma/mortalidade , Melanoma/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Pele/patologia , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Taxa de Sobrevida
13.
Scand J Med Sci Sports ; 27(7): 714-723, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27183922

RESUMO

Erythropoietin (EPO) rapidly decreases on return to sea level (SL) after chronic altitude exposure. Acute hypoxia may provide an additional stimulus to prevent the decline in EPO. Proinflammatory cytokines, interleukin-6 (IL-6), and tumor necrosis factor alpha (TNFα) have been shown to inhibit EPO production. Optimal normobaric hypoxic exposure has not been established; therefore, investigation of methods eliciting the greatest response in EPO to limit physiological stress is required. Eight men (age 27 ± 4 years, body mass 77.5 ± 9.0 kg, height 179 ± 6 cm) performed four passive exposures to different normobaric hypoxic severities [FiO2 : 0.209 (SL), FiO2 : ~0.135 (3600 m), FiO2 : ~0.125 (4200 m) and FiO2 : ~0.115 (4800 m)] in a hypoxic chamber for 2 h. Venous blood was drawn pre-exposure and then at 1, 2, 4, 6, and 8 h to determine EPO concentration ([EPO]), IL-6, and TNFα. During 4200 and 4800 m, [EPO] increased from 5.9 ± 1.5 to 8.1 ± 1.5 mU/mL (P = 0.009) and 6.0 ± 1.4 to 8.9 ± 2.0 mU/mL (P = 0.037), respectively, with [EPO] increase peaking at 4 h (2 h post-exposure). There were no differences in IL-6 or TNFα during or post-exposure. Increased [EPO] was found 2 h post hypoxic exposure as result of 2 h of normobaric hypoxia ≥4200 m. There was no dose-response relationship in [EPO] between simulated hypoxia severities.


Assuntos
Altitude , Eritropoetina/sangue , Hipóxia/sangue , Interleucina-6/sangue , Fator de Necrose Tumoral alfa/sangue , Adulto , Humanos , Masculino , Método Simples-Cego , Fatores de Tempo , Adulto Jovem
14.
Methods Cell Biol ; 136: 1-19, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27473900

RESUMO

We have confirmed and extended previous reports of a wide distribution of septin proteins in the eukaryotic phylogeny. It now appears that septins are present in at least some representatives of every eukaryotic supergroup, with the possible exception of the Excavata. Presently, almost nothing is known of the structure, assembly, and biological roles of septins outside of the opisthokonts (animals, fungi, and their close relatives). Thus, studies of the septins in the highly diverse and distantly related nonopisthokont groups present a major opportunity to gain a much deeper understanding of septin core function and evolution, and we discuss briefly the excellent prospects for capitalizing on this opportunity in the next few years.


Assuntos
Evolução Molecular , Biologia Molecular/métodos , Filogenia , Septinas/genética , Divisão Celular , Septinas/química , Septinas/classificação
15.
Mod Pathol ; 29(2): 112-21, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26743475

RESUMO

Malignant melanoma is an aggressive form of skin cancer. Recently, drug therapy of advanced disease has been revolutionized by new agents. More therapeutic options, coupled with the desire to extend treatment to the adjuvant setting mean that prognostic biomarkers that can be assayed from formalin-fixed paraffin-embedded clinical would be valuable. microRNAs have potential to fill this need. We analyzed 377 microRNAs in 79 primary melanomas and 32 metastases using a split sample discovery strategy. From a discovery analysis using 40 thick primary melanomas (20 cases with metastasis and 20 controls without metastasis at 5 years), microRNA expression was measured by quantitative RT-PCR (QRT-PCR). MiR-10b emerged as a candidate prognostic microRNA. This was confirmed in an independent validation set of thick primary melanomas (20 cases with metastasis and 19 controls without metastasis at 5 years). In the combined discovery and validation cohorts (n=79), miR-10b expression showed a 3.7-fold increase in expression between cases and controls (P=0.005) and showed a trend of increasing expression between primary melanomas and their matched metastases (P<0.001). In situ hybridization showed expression was in melanoma cells and correlated with expression measured by QRT-PCR (P=0.0005). We used the combined discovery and validation samples to verify the prognostic value of additional candidate microRNAs identified from other studies, and proceeded to analyze miR-200b. We demonstrated that miR-10b and miR-200b showed independent prognostic value (P=0.002 and 0.047, respectively) in multivariable analysis alongside known clinico-pathological prognostic features (eg, Breslow thickness) using a Cox proportional hazards regression model. Furthermore, the addition of these microRNAs to the clinico-pathological features led to an improved regression model with better identification of aggressive thick melanomas. Taken together, these data suggest that miR-10b is a new prognostic microRNA for melanoma and that there could be a place for microRNA analysis in stratifying melanoma for therapy.


Assuntos
Biomarcadores Tumorais/genética , Melanoma/genética , MicroRNAs/genética , Neoplasias Cutâneas/genética , Idoso , Feminino , Estudos de Associação Genética , Humanos , Modelos Logísticos , Masculino , Melanoma/secundário , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Cutâneas/patologia
16.
Oncogene ; 35(12): 1483-92, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-26096930

RESUMO

Inhibition of the chaperone heat-shock protein 90 (HSP90) induces apoptosis, and it is a promising anti-cancer strategy. The mechanisms underpinning apoptosis activation following HSP90 inhibition and how they are modified during acquired drug resistance are unknown. We show for the first time that, to induce apoptosis, HSP90 inhibition requires the cooperation of multi BH3-only proteins (BID, BIK, PUMA) and the reciprocal suppression of the pro-survival BCL-2 family member MCL1, which occurs via inhibition of STAT5A. A subset of tumour cell lines exhibit dependence on MCL1 expression for survival and this dependence is also associated with tumour response to HSP90 inhibition. In the acquired resistance setting, MCL1 suppression in response to HSP90 inhibitors is maintained; however, a switch in MCL1 dependence occurs. This can be exploited by the BH3 peptidomimetic ABT737, through non-BCL-2-dependent synthetic lethality.


Assuntos
Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Linhagem Celular Tumoral , Humanos , Peptidomiméticos , Fator de Transcrição STAT5/genética , Proteínas Supressoras de Tumor/genética
17.
Clin Chem ; 61(7): 974-82, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25979954

RESUMO

BACKGROUND: Activating mutations in the estrogen receptor 1 (ESR1) gene are acquired on treatment and can drive resistance to endocrine therapy. Because of the spatial and temporal limitations of needle core biopsies, our goal was to develop a highly sensitive, less invasive method of detecting activating ESR1 mutations via circulating cell-free DNA (cfDNA) and tumor cells as a "liquid biopsy." METHODS: We developed a targeted 23-amplicon next-generation sequencing (NGS) panel for detection of hot-spot mutations in ESR1, phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA), tumor protein p53 (TP53), fibroblast growth factor receptor 1 (FGFR1), and fibroblast growth factor receptor 2 (FGFR2) in 48 patients with estrogen receptor-α-positive metastatic breast cancer who were receiving systemic therapy. Selected mutations were validated using droplet digital PCR (ddPCR). RESULTS: Nine baseline cfDNA samples had an ESR1 mutation. NGS detected 3 activating mutations in ESR1, and 3 hot-spot mutations in PIK3CA, and 3 in TP53 in baseline cfDNA, and the ESR1 p.D538G mutation in 1 matched circulating tumor cell sample. ddPCR analysis was more sensitive than NGS and identified 6 additional baseline cfDNA samples with the ESR1 p.D538G mutation at a frequency of <1%. In serial blood samples from 11 patients, 4 showed changes in cfDNA, 2 with emergence of a mutation in ESR1. We also detected a low frequency ESR1 mutation (1.3%) in cfDNA of 1 primary patient who was thought to have metastatic disease but was clear by scans. CONCLUSIONS: Early identification of ESR1 mutations by liquid biopsy might allow for cessation of ineffective endocrine therapies and switching to other treatments, without the need for tissue biopsy and before the emergence of metastatic disease.


Assuntos
Neoplasias da Mama/genética , Análise Mutacional de DNA/métodos , Receptor alfa de Estrogênio/genética , Mutação , Células Neoplásicas Circulantes , Neoplasias da Mama/patologia , Classe I de Fosfatidilinositol 3-Quinases , Receptor alfa de Estrogênio/sangue , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Células Neoplásicas Circulantes/patologia , Fosfatidilinositol 3-Quinases/genética , Reprodutibilidade dos Testes , Proteína Supressora de Tumor p53/genética
18.
Epidemiol Infect ; 143(15): 3227-34, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25865382

RESUMO

On 23 May 2011, CDC identified a multistate cluster of Salmonella Heidelberg infections and two multidrug-resistant (MDR) isolates from ground turkey retail samples with indistinguishable pulsed-field gel electrophoresis patterns. We defined cases as isolation of outbreak strains in persons with illness onset between 27 February 2011 and 10 November 2011. Investigators collected hypothesis-generating questionnaires and shopper-card information. Food samples from homes and retail outlets were collected and cultured. We identified 136 cases of S. Heidelberg infection in 34 states. Shopper-card information, leftover ground turkey from a patient's home containing the outbreak strain and identical antimicrobial resistance profiles of clinical and retail samples pointed to plant A as the source. On 3 August, plant A recalled 36 million pounds of ground turkey. This outbreak increased consumer interest in MDR Salmonella infections acquired through United States-produced poultry and played a vital role in strengthening food safety policies related to Salmonella and raw ground poultry.


Assuntos
Surtos de Doenças , Farmacorresistência Bacteriana Múltipla , Microbiologia de Alimentos , Indústria de Embalagem de Carne , Intoxicação Alimentar por Salmonella/epidemiologia , Salmonella/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Eletroforese em Gel de Campo Pulsado , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Salmonella/efeitos dos fármacos , Salmonella/isolamento & purificação , Intoxicação Alimentar por Salmonella/microbiologia , Perus , Estados Unidos/epidemiologia , Adulto Jovem
19.
Epidemiol Infect ; 143(10): 2178-86, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25703600

RESUMO

Human salmonellosis linked to contact with live poultry is an increasing public health concern. In 2012, eight unrelated outbreaks of human salmonellosis linked to live poultry contact resulted in 517 illnesses. In July 2012, PulseNet, a national molecular surveillance network, reported a multistate cluster of a rare strain of Salmonella Braenderup infections which we investigated. We defined a case as infection with the outbreak strain, determined by pulsed-field gel electrophoresis, with illness onset from 25 July 2012-27 February 2013. Ill persons and mail-order hatchery (MOH) owners were interviewed using standardized questionnaires. Traceback and environmental investigations were conducted. We identified 48 cases in 24 states. Twenty-six (81%) of 32 ill persons reported live poultry contact in the week before illness; case-patients named 12 different MOHs from eight states. The investigation identified hatchery D as the ultimate poultry source. Sampling at hatchery D yielded the outbreak strain. Hatchery D improved sanitation procedures and pest control; subsequent sampling failed to yield Salmonella. This outbreak highlights the interconnectedness of humans, animals, and the environment and the importance of industry knowledge and involvement in solving complex outbreaks. Preventing these infections requires a 'One Health' approach that leverages expertise in human, animal, and environmental health.


Assuntos
Surtos de Doenças , Infecções por Salmonella/epidemiologia , Salmonella enterica/isolamento & purificação , Zoonoses/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Eletroforese em Gel de Campo Pulsado , Feminino , Humanos , Lactente , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Serviços Postais , Aves Domésticas , Infecções por Salmonella/microbiologia , Salmonella enterica/classificação , Salmonella enterica/genética , Estados Unidos/epidemiologia , Adulto Jovem , Zoonoses/microbiologia
20.
Colorectal Dis ; 17(7): 578-88, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25557290

RESUMO

AIM: MicroRNAs (miRNAs) from tumour tissue and common gene mutations were studied to determine whether they predict the development of metastasis in patients with Dukes B colorectal cancer. METHOD: Patients who underwent curative resection for Dukes B colorectal cancer who subsequently developed distant metastatic disease at some stage in the following 5 years ('high-risk B') were compared with case-matched controls of Dukes A, Dukes B (no metastases, 'low-risk B') and Dukes C patients without any detectable metastasis at 5 years of follow-up. MiRNAs from tumour and adjacent normal tissue and common gene mutations (KRAS, BRAF, PIK3CA) in primary cancer tissue were analysed to identify prognostic tissue markers for the development of metastasis in patients with Dukes B colorectal cancer. RESULTS: Expression of miR-15b and miR-135b was significantly downregulated (P < 0.001) in 'high-risk B' tumours compared with Dukes A, 'low-risk B' and C without metastasis. No significant differences were noted for mutation status and the development of metastasis. CONCLUSION: The study suggests that the development of metastasis in Dukes B tumours may be predictable based on the miRNA expression of miR-15b and miR-135b. This requires further study on a much larger cohort.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Perfilação da Expressão Gênica , MicroRNAs/análise , Metástase Neoplásica/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Classe I de Fosfatidilinositol 3-Quinases , Regulação para Baixo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Fosfatidilinositol 3-Quinases/genética , Prognóstico , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Fatores de Risco
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