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1.
Biomolecules ; 12(10)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36291720

RESUMO

Loss PTEN function is one of the most common events driving aggressive prostate cancers and biochemically, PTEN is a lipid phosphatase which opposes the activation of the oncogenic PI3K-AKT signalling network. However, PTEN also has additional potential mechanisms of action, including protein phosphatase activity. Using a mutant enzyme, PTEN Y138L, which selectively lacks protein phosphatase activity, we characterised genetically modified mice lacking either the full function of PTEN in the prostate gland or only lacking protein phosphatase activity. The phenotypes of mice carrying a single allele of either wild-type Pten or PtenY138L in the prostate were similar, with common prostatic intraepithelial neoplasia (PIN) and similar gene expression profiles. However, the latter group, lacking PTEN protein phosphatase activity additionally showed lymphocyte infiltration around PIN and an increased immune cell gene expression signature. Prostate adenocarcinoma, elevated proliferation and AKT activation were only frequently observed when PTEN was fully deleted. We also identify a common gene expression signature of PTEN loss conserved in other studies (including Nkx3.1, Tnf and Cd44). We provide further insight into tumour development in the prostate driven by loss of PTEN function and show that PTEN protein phosphatase activity is not required for tumour suppression.


Assuntos
PTEN Fosfo-Hidrolase , Neoplasias da Próstata , Animais , Masculino , Camundongos , Lipídeos , Fosfatidilinositol 3-Quinases/metabolismo , Fosfoproteínas Fosfatases , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo
2.
Educ Inf Technol (Dordr) ; 27(5): 6691-6713, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35095325

RESUMO

This paper presents data from two international projects focused on the interaction between changemaking and digital making in university students. The data is drawn from the contributions of 63 university students located in the United States, Romania, Spain, Belgium, Norway, Denmark and England. Using a design thinking methodology and a thematic analysis of student responses, the aim was to understand how the creative use of immersive technologies, such as augmented and virtual reality, might create an environment for changemaking practices in an international context. Findings suggest that students demonstrated not only enhanced digital skills and student engagement but increased cultural competence and global mindfulness. International digital collaboration can create conditions for students to develop changemaker attributes and identify as changemakers within the spheres of entrepreneurship and education, preparing them to be a force for change in the world.

3.
Mod Pathol ; 34(11): 2009-2019, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34155350

RESUMO

Dedifferentiation and transdifferentiation are rare and only poorly understood phenomena in cutaneous melanoma. To study this disease more comprehensively we have retrieved 11 primary cutaneous melanomas from our pathology archives showing biphasic features characterized by a conventional melanoma and additional areas of de-/trans-differentiation as defined by a lack of immunohistochemical expression of all conventional melanocytic markers (S-100 protein, SOX10, Melan-A, and HMB-45). The clinical, histologic, and immunohistochemical findings were recorded and follow-up was obtained. The patients were mostly elderly (median: 81 years; range: 42-86 years) without significant gender predilection, and the sun-exposed skin of the head and neck area was most commonly affected. The tumors were deeply invasive with a mean depth of 7 mm (range: 4-80 mm). The dedifferentiated component showed atypical fibroxanthoma-like features in the majority of cases (7), while additional rhabdomyosarcomatous and epithelial transdifferentiation was noted histologically and/or immunohistochemically in two tumors each. The background conventional melanoma component was of desmoplastic (4), superficial spreading (3), nodular (2), lentigo maligna (1), or spindle cell (1) types. For the seven patients with available follow-up data (median follow-up period of 25 months; range: 8-36 months), two died from their disease, and three developed metastases. Next-generation sequencing of the cohort revealed somatic mutations of established melanoma drivers including mainly NF1 mutations (5) in the conventional component, which was also detected in the corresponding de-/trans-differentiated component. In summary, the diagnosis of primary cutaneous de-/trans-differentiated melanoma is challenging and depends on the morphologic identification of conventional melanoma. Molecular analysis is diagnostically helpful as the mutated gene profile is shared between the conventional and de-/trans-differentiated components. Importantly, de-/trans-differentiation does not appear to confer a more aggressive behavior.


Assuntos
Genômica , Melanoma/patologia , Neurofibromina 1/genética , Neoplasias Cutâneas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Diferenciação Celular , DNA de Neoplasias/genética , Diagnóstico Diferencial , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Melanoma/genética , Melanoma/metabolismo , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo
4.
Cancers (Basel) ; 12(12)2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33302429

RESUMO

Mutations in the isocitrate dehydrogenase 1 (IDH1) gene are found in a high proportion of diffuse gliomas. The presence of the IDH1 mutation is a valuable diagnostic, prognostic and predictive biomarker for the management of patients with glial tumours. Techniques involving vibrational spectroscopy, e.g., Fourier transform infrared (FTIR) spectroscopy, have previously demonstrated analytical capabilities for cancer detection, and have the potential to contribute to diagnostics. The implementation of FTIR microspectroscopy during surgical biopsy could present a fast, label-free method for molecular genetic classification. For example, the rapid determination of IDH1 status in a patient with a glioma diagnosis could inform intra-operative decision-making between alternative surgical strategies. In this study, we utilized synchrotron-based FTIR microanalysis to probe tissue microarray sections from 79 glioma patients, and distinguished the positive class (IDH1-mutated) from the IDH1-wildtype glioma, with a sensitivity and specificity of 82.4% and 83.4%, respectively. We also examined the ability of attenuated total reflection (ATR)-FTIR spectroscopy in detecting the biomolecular events and global epigenetic and metabolic changes associated with mutations in the IDH1 enzyme, in blood serum samples collected from an additional 72 brain tumour patients. Centrifugal filtration enhanced the diagnostic ability of the classification models, with balanced accuracies up to ~69%. Identification of the molecular status from blood serum prior to biopsy could further direct some patients to alternative treatment strategies.

5.
Gut ; 69(8): 1382-1403, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32467090

RESUMO

Liver biopsy is required when clinically important information about the diagnosis, prognosis or management of a patient cannot be obtained by safer means, or for research purposes. There are several approaches to liver biopsy but predominantly percutaneous or transvenous approaches are used. A wide choice of needles is available and the approach and type of needle used will depend on the clinical state of the patient and local expertise but, for non-lesional biopsies, a 16-gauge needle is recommended. Many patients with liver disease will have abnormal laboratory coagulation tests or receive anticoagulation or antiplatelet medication. A greater understanding of the changes in haemostasis in liver disease allows for a more rational, evidence-based approach to peri-biopsy management. Overall, liver biopsy is safe but there is a small morbidity and a very small mortality so patients must be fully counselled. The specimen must be of sufficient size for histopathological interpretation. Communication with the histopathologist, with access to relevant clinical information and the results of other investigations, is essential for the generation of a clinically useful report.


Assuntos
Biópsia/métodos , Biópsia/normas , Fígado/patologia , Antibioticoprofilaxia , Anticoagulantes/uso terapêutico , Biópsia/efeitos adversos , Biópsia/instrumentação , Testes de Coagulação Sanguínea , Contraindicações de Procedimentos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Humanos , Consentimento Livre e Esclarecido , Comunicação Interdisciplinar , Laparoscopia , Agulhas , Seleção de Pacientes , Cuidados Pós-Operatórios/normas , Papel Profissional
6.
Nurs Stand ; 2019 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31468895

RESUMO

Hepatitis C is a blood-borne virus that, if left untreated, can result in significant liver damage and cancer. Most individuals are unaware that they have been infected with the hepatitis C virus and remain asymptomatic, which makes early diagnosis challenging. While the virus will spontaneously clear in some individuals, the majority will develop chronic hepatitis C. This article provides nurses with an overview of hepatitis C and how it is transmitted. It details the available treatments, and examines the challenges involved in early identification and access to treatment, as well as outlining the barriers to treatment and how these can be overcome. This article also discusses the role of the nurse in the management of people with hepatitis C and in addressing their complex needs.

7.
J Vis Exp ; (71)2013 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-23380956

RESUMO

Currently there is no curative treatment for metastatic clear cell renal cell cancer, the commonest variant of the disease. A key factor in this treatment resistance is thought to be the molecular complexity of the disease. Targeted therapy such as the tyrosine kinase inhibitor (TKI)-sunitinib have been utilized, but only 40% of patients will respond, with the overwhelming majority of these patients relapsing within 1 year. As such the question of intrinsic and acquired resistance in renal cell cancer patients is highly relevant. In order to study resistance to TKIs, with the ultimate goal of developing effective, personalized treatments, sequential tissue after a specific period of targeted therapy is required, an approach which had proved successful in chronic myeloid leukaemia. However the application of such a strategy in renal cell carcinoma is complicated by the high level of both inter- and intratumoral heterogeneity, which is a feature of renal cell carcinoma as well as other solid tumors. Intertumoral heterogeneity due to transcriptomic and genetic differences is well established even in patients with similar presentation, stage and grade of tumor. In addition it is clear that there is great morphological (intratumoral) heterogeneity in RCC, which is likely to represent even greater molecular heterogeneity. Detailed mapping and categorization of RCC tumors by combined morphological analysis and Fuhrman grading allows the selection of representative areas for proteomic analysis. Protein based analysis of RCC is attractive due to its widespread availability in pathology laboratories; however, its application can be problematic due to the limited availability of specific antibodies. Due to the dot blot nature of the Reverse Phase Protein Arrays (RPPA), antibody specificity must be pre-validated; as such strict quality control of antibodies used is of paramount importance. Despite this limitation the dot blot format does allow assay miniaturization, allowing for the printing of hundreds of samples onto a single nitrocellulose slide. Printed slides can then be analyzed in a similar fashion to Western analysis with the use of target specific primary antibodies and fluorescently labelled secondary antibodies, allowing for multiplexing. Differential protein expression across all the samples on a slide can then be analyzed simultaneously by comparing the relative level of fluorescence in a more cost-effective and high-throughput manner.


Assuntos
Carcinoma de Células Renais/metabolismo , Neoplasias Renais/metabolismo , Proteínas de Neoplasias/biossíntese , Análise Serial de Proteínas/métodos , Western Blotting , Carcinoma de Células Renais/patologia , Humanos , Neoplasias Renais/patologia
8.
Oncotarget ; 3(6): 608-19, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22689141

RESUMO

High expression of Rac small GTPases in invasive breast ductal carcinoma is associated with poor prognosis, but its therapeutic value in human cancers is not clear. The aim of the current study was to determine the response of human primary breast cancers to Rac-based drug treatments ex vivo. Three-dimensional organotypic cultures were used to assess candidate therapeutic avenues in invasive breast cancers. Uniquely, in these primary cultures, the tumour is not disaggregated, with both epithelial and mesenchymal components maintained within a 3-dimensional matrix of type I collagen. EHT 1864, a small molecule inhibitor of Rac GTPases, prevents spread of breast cancers in this setting, and also reduces proliferation at the invading edge. Rac1+ epithelial cells in breast tumours also contain high levels of the phosphorylated form of the transcription factor STAT3. The small molecule Stattic inhibits activation of STAT3 and induces effects similar to those seen with EHT 1864. Pan-Rac inhibition of proliferation precedes down-regulation of STAT3 activity, defining it as the last step in Rac activation during human breast cancer invasion. Our data highlights the potential use of Rac and STAT3 inhibition in treatment of invasive human breast cancer and the benefit of studying novel cancer treatments using 3-dimensional primary tumour tissue explant cultures.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Carcinoma Ductal de Mama/tratamento farmacológico , Pironas/farmacologia , Quinolinas/farmacologia , Proteínas rac1 de Ligação ao GTP/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo , Feminino , Humanos , Terapia de Alvo Molecular , Fator de Transcrição STAT3/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Proteínas rac1 de Ligação ao GTP/biossíntese , Proteínas rac1 de Ligação ao GTP/genética
9.
PLoS One ; 6(2): e17083, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21347235

RESUMO

The epithelial to mesenchymal transition (EMT) is a developmental program in which epithelial cells down-regulate their cell-cell junctions, acquire spindle cell morphology and exhibit cellular motility. In human breast cancer, invasion into surrounding tissue is the first step in metastatic progression. Here, we devised an in vitro model using selected cell lines, which recapitulates many features of EMT as observed in human breast cancer. By comparing the gene expression profiles of claudin-low breast cancers with the experimental model, we identified a 9-gene signature characteristic of EMT. This signature was found to distinguish a series of breast cancer cell lines that have demonstrable, classical EMT hallmarks, including loss of E-cadherin protein and acquisition of N-cadherin and vimentin expression. We subsequently developed a three-dimensional model to recapitulate the process of EMT with these cell lines. The cells maintain epithelial morphology when encapsulated in a reconstituted basement membrane, but undergo spontaneous EMT and invade into surrounding collagen in the absence of exogenous cues. Collectively, this model of EMT in vitro reveals the behaviour of breast cancer cells beyond the basement membrane breach and recapitulates the in vivo context for further investigation into EMT and drugs that may interfere with it.


Assuntos
Neoplasias da Mama/patologia , Transição Epitelial-Mesenquimal , Modelos Biológicos , Sequência de Aminoácidos , Sequência de Bases , Membrana Basal/metabolismo , Membrana Basal/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Claudinas/genética , Claudinas/metabolismo , Colágeno/metabolismo , Transição Epitelial-Mesenquimal/genética , Feminino , Humanos , Dados de Sequência Molecular , Invasividade Neoplásica , Células Estromais/metabolismo , Células Estromais/patologia , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
10.
Chemistry ; 15(26): 6468-77, 2009 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-19466722

RESUMO

Green and fast: Allylation of aromatic and aliphatic thiols, by using allyl alcohols as substrates, requires only minutes at ambient temperature with a Ru catalyst (see scheme). Quantitative conversion is normal and the catalyst possesses high functional-group tolerance.The allylation of aromatic and aliphatic thiols, by using allyl alcohols as substrates, requires only minutes at ambient temperature with either a Ru(IV) catalyst, [Ru(Cp*)(eta(3)-C(3)H(5))(CH(3)CN)(2)](PF(6))(2) (2; Cp*=pentamethylcyclopentadienyl) or a combination of [Ru(Cp*)(CH(3)CN)(3)](PF(6)) and camphor sulfonic acid. Quantitative conversion is normal and the catalyst possesses high functional-group tolerance. The use of [Ru(Cp*)(CH(3)CN)(3)](PF(6)) alone affords poor results. A comparison is made to the results from catalytic runs based on the use of carbonates rather than alcohols, by using 2 as the catalyst, and it is shown that the products from the alcohols are formed faster, so there is no advantage in using a carbonate substrate. The observed branched-to-linear (b/l) ratios when using substituted alcohols decrease with time suggesting that the catalysts isomerise the products. A new methodology from which one can select the desired isomeric product is proposed. DFT calculations and NMR spectroscopic measurements, by using an arene sulfonic acid as co-catalyst, suggest that eta(6)-complexes are not relevant for the catalytic system. Moreover, the DFT results indicate that 1) any eta(6)-complexes from the acids RC(6)H(4)SO(3)H result from deprotonation of the acid, 2) complexation of the thiol, via the deprotonated sulfur atom, is preferred over complexation of the O atom of the sulfonate, RC(6)H(4)SO(3) (-) and 3) a sulfonate O-atom complex will be difficult to detect.

11.
Mamm Genome ; 18(9): 617-26, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17726633

RESUMO

Polyploidisation in hepatocytes has been associated with many physiologic and pathologic processes such as proliferation, metabolism, regeneration, aging, and cancer. We studied gene expression patterns in hepatocytes of different ploidy. Primary hepatocytes were obtained from mice of different ages: young (4-6 weeks old), adult (8-10 weeks old), and older (22-24 weeks old). Diploid (2N), tetraploid (4N), and octoploid (8N) hepatocytes were isolated for studies using a high-density mouse genome microarray. No major changes of gene expression patterns between hepatocytes of different ploidy were found. Fifty genes were identified as differentially expressed in the diploid and tetraploid populations, but the changes were less than twofold either way. Four genes (Gas2, Igfbp2, Nr1i3, and Ccne2) were differentially expressed in tetraploid and octoploid cells. This was confirmed in two age groups, "adult" and "older," but once again the factors were less than twofold and the expressions of Gas2 and Igfbp2 were more different between age groups than between ploidy classes. Our results show that polyploid hepatocytes are stable and "normal" without aberrant gene expression, unlike what is thought for cancer cells. By contrast to megakaryocytes, hepatocyte polyploidisation is not a differentiation step associated with major changes in gene expression. Our data support the hypothesis that hepatocyte polyploidisation is a protective mechanism against oxidative stress that occurs via a controlled process throughout growth and aging where binucleation is important.


Assuntos
Perfilação da Expressão Gênica , Hepatócitos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Poliploidia , Envelhecimento/genética , Animais , Separação Celular , Receptor Constitutivo de Androstano , Citometria de Fluxo , Hepatócitos/citologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Int J Mol Med ; 12(6): 889-94, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14612962

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, usually arising from a background of chronic inflammatory disease. Tumor necrosis factor alpha (TNF-alpha) is a pro-inflammatory cytokine produced in response to tissue injury, endotoxin exposure or infection and TNF-alpha signalling in hepatocytes is associated with an increase in oxidative stress. DNA is vulnerable to reactive oxygen species (ROS)-induced damage, which is highly mutagenic. Cells respond to DNA damage through the stabilisation of the tumor suppressor p53, which maintains genomic fidelity through induction of a cell cycle arrest in order to allow repair or elimination of the damaged cell through apoptosis. This study was carried out to determine if TNF-alpha caused oxidative DNA damage in primary cultures of murine hepatocytes and whether any damage would result in the induction of the tumor suppressor p53 and cell-cycle arrest. Using a modified Comet assay, to measure DNA damage we have demonstrated that TNF-alpha causes the formation of 8-oxo-deoxyguanosine (8-oxodG), an established marker of oxidative DNA damage, and a lesion associated with chronic hepatitis in human livers. In addition, the increase in DNA damage did not result in p53 stabilisation and TNF-alpha caused an increase in cell-cycle progression. We believe that this study indicates a possible putative role for TNF-alpha in the early stages of malignant transformation of hepatocytes.


Assuntos
Antineoplásicos/farmacologia , Dano ao DNA , Hepatócitos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Animais , Apoptose/fisiologia , Divisão Celular/fisiologia , Camundongos , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
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