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1.
J Am Med Inform Assoc ; 23(6): 1185-1189, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27094989

RESUMO

OBJECTIVE: To develop a secure, efficient, and easy-to-use data collection platform to measure the prevalence of sepsis in Wales over 24 hours. MATERIALS AND METHODS: Open Data Kit was used on Android devices with Google App Engine and a digital data collection form. RESULTS: A total of 184 students participated in the study using 59 devices across 16 hospitals, 1198 datasets were submitted, and 97% of participants found the Open Data Kit form easy to use. DISCUSSION: We successfully demonstrated that by combining a reliable Android device, a free open-source data collection framework, a scalable cloud-based server, and a team of 184 medical students, we can deliver a low-cost, highly reliable platform that requires little training or maintenance, providing results immediately on completion of data collection. CONCLUSION: Our platform allowed us to measure, for the first time, the prevalence of sepsis in Wales over 24 hours.


Assuntos
Coleta de Dados/métodos , Aplicativos Móveis , Sepse/epidemiologia , Educação Médica , Humanos , Prevalência , Estudantes de Medicina , País de Gales/epidemiologia
2.
Oncogene ; 35(23): 3004-15, 2016 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-26434594

RESUMO

Tumour cells can use strategies that make them resistant to nutrient deprivation to outcompete their neighbours. A key integrator of the cell's responses to starvation and other stresses is amino-acid-dependent mechanistic target of rapamycin complex 1 (mTORC1). Activation of mTORC1 on late endosomes and lysosomes is facilitated by amino-acid transporters within the solute-linked carrier 36 (SLC36) and SLC38 families. Here, we analyse the functions of SLC36 family member, SLC36A4, otherwise known as proton-assisted amino-acid transporter 4 (PAT4), in colorectal cancer. We show that independent of other major pathological factors, high PAT4 expression is associated with reduced relapse-free survival after colorectal cancer surgery. Consistent with this, PAT4 promotes HCT116 human colorectal cancer cell proliferation in culture and tumour growth in xenograft models. Inducible knockdown in HCT116 cells reveals that PAT4 regulates a form of mTORC1 with two distinct properties: first, it preferentially targets eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1), and second, it is resistant to rapamycin treatment. Furthermore, in HCT116 cells two non-essential amino acids, glutamine and serine, which are often rapidly metabolised by tumour cells, regulate rapamycin-resistant mTORC1 in a PAT4-dependent manner. Overexpressed PAT4 is also able to promote rapamycin resistance in human embryonic kidney-293 cells. PAT4 is predominantly associated with the Golgi apparatus in a range of cell types, and in situ proximity ligation analysis shows that PAT4 interacts with both mTORC1 and its regulator Rab1A on the Golgi. These findings, together with other studies, suggest that differentially localised intracellular amino-acid transporters contribute to the activation of alternate forms of mTORC1. Furthermore, our data predict that colorectal cancer cells with high PAT4 expression will be more resistant to depletion of serine and glutamine, allowing them to survive and outgrow neighbouring normal and tumorigenic cells, and potentially providing a new route for pharmacological intervention.


Assuntos
Sistemas de Transporte de Aminoácidos/metabolismo , Aminoácidos/metabolismo , Neoplasias Colorretais/metabolismo , Complexo de Golgi/metabolismo , Complexos Multiproteicos/metabolismo , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo , Sistemas de Transporte de Aminoácidos/biossíntese , Animais , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Resistencia a Medicamentos Antineoplásicos , Feminino , Células HCT116 , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Camundongos SCID , Transdução de Sinais , Resultado do Tratamento
3.
Br J Cancer ; 112(1): 52-60, 2015 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-25461806

RESUMO

PURPOSE: To assess whether the combination of letrozole, metronomic cyclophosphamide and sorafenib (LCS) is well tolerated and shows activity in primary breast cancer (BC). METHODS: Thirteen oestrogen receptor-positive, postmenopausal, T2-4, N0-1 BC patients received the LCS combination for 6 months. In these patients we examined the pharmacokinetics of sorafenib and cyclophosphamide, toxicity of the regimen, the clinical response to therapy and changes in the levels of biologically relevant biomarkers. RESULTS: Adequate plasma concentrations of sorafenib were achieved in patients when it was dosed in combination with L+C. The mean plasma concentrations of C were consistently lower following administration of LCS, compared with administration of L+C only. The most common drug-related grade 3/4 adverse events were skin rash (69.3%), hand-foot skin reaction (69.3%) and diarrhoea (46.1%). According to RECIST Criteria, a clinical complete response was observed in 6 of 13 patients. A significant reduction in tumour size, evaluated with MRI, was also observed between baseline and 14 days of treatment in all 13 patients (P=0.005). A significant reduction in SUV uptake, measured by (18)FDG-PET/CT, was observed in all patients between baseline and 30 days of treatment (P=0.015) and between baseline and definitive surgery (P=0.0002). Using modified CT Criteria, a response was demonstrated in 8 out of 10 evaluable patients at 30 days and in 11 out of 13 evaluable patients at the definitive surgery. A significant reduction in Ki67 expression was observed in all patients at day 14 compared with baseline (P<0.00001) and in 9 out of 13 patients at the definitive surgery compared with baseline (P<0.03). There was also a significant suppression of CD31 and VEGF-A expression in response to treatment (P=0.01 and P=0.007, respectively). CONCLUSIONS: The LCS combination is feasible and tolerable. The tumour response and target biomarker modulation indicate that the combination is clinically and biologically active.


Assuntos
Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Administração Metronômica , Idoso , Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Ciclofosfamida/farmacocinética , Feminino , Humanos , Letrozol , Pessoa de Meia-Idade , Niacinamida/administração & dosagem , Niacinamida/efeitos adversos , Niacinamida/análogos & derivados , Niacinamida/farmacocinética , Nitrilas/administração & dosagem , Nitrilas/efeitos adversos , Nitrilas/farmacocinética , Compostos de Fenilureia/administração & dosagem , Compostos de Fenilureia/efeitos adversos , Compostos de Fenilureia/farmacocinética , Ensaios Clínicos Controlados Aleatórios como Assunto , Sorafenibe , Triazóis/administração & dosagem , Triazóis/efeitos adversos , Triazóis/farmacocinética
4.
Chem Commun (Camb) ; 50(12): 1472-4, 2014 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-24362918

RESUMO

The surface-enhanced hyper-Raman scattering (SEHRS) of three analyte molecules has been obtained with excitation wavelengths at 1.55 and 1.8 µm. At 1.55 µm, excellent signal-to-noise ratios under modest experimental parameters demonstrate compelling potential for practical applications in chemical analysis and molecular imaging.


Assuntos
Raios Infravermelhos , Imagem Molecular/instrumentação , Técnicas de Química Analítica/instrumentação , Coloides/química , Tamanho da Partícula , Razão Sinal-Ruído , Prata/química , Análise Espectral Raman , Propriedades de Superfície
5.
Br J Cancer ; 109(1): 50-9, 2013 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-23778527

RESUMO

BACKGROUND: Non-muscle invasive (NMI) bladder cancer is characterised by increased expression and activating mutations of FGFR3. We have previously investigated the role of microRNAs in bladder cancer and have shown that FGFR3 is a target of miR-100. In this study, we investigated the effects of hypoxia on miR-100 and FGFR3 expression, and the link between miR-100 and FGFR3 in hypoxia. METHODS: Bladder cancer cell lines were exposed to normoxic or hypoxic conditions and examined for the expression of FGFR3 by quantitative PCR (qPCR) and western blotting, and miR-100 by qPCR. The effect of FGFR3 and miR-100 on cell viability in two-dimensional (2-D) and three-dimensional (3-D) was examined by transfecting siRNA or mimic-100, respectively. RESULTS: In NMI bladder cancer cell lines, FGFR3 expression was induced by hypoxia in a transcriptional and HIF-1α-dependent manner. Increased FGFR3 was also in part dependent on miR-100 levels, which decreased in hypoxia. Knockdown of FGFR3 led to a decrease in phosphorylation of the downstream kinases mitogen-activated protein kinase (MAPK) and protein kinase B (PKB), which was more pronounced under hypoxic conditions. Furthermore, transfection of mimic-100 also decreased phosphorylation of MAPK and PKB. Finally, knocking down FGFR3 profoundly decreased 2-D and 3-D cell growth, whereas introduction of mimic-100 decreased 3-D growth of cells. CONCLUSION: Hypoxia, in part via suppression of miR-100, induces FGFR3 expression in bladder cancer, both of which have an important role in maintaining cell viability under conditions of stress.


Assuntos
Hipóxia Celular/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , MicroRNAs/metabolismo , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica , Interferência de RNA , RNA Interferente Pequeno , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/biossíntese , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Transcrição Gênica , Neoplasias da Bexiga Urinária/patologia
6.
Virchows Arch ; 462(4): 465-72, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23511993

RESUMO

Adipocyte P2 (aP2), also known as fatty acid-binding protein 4 (FABP4), is a fatty acid-binding protein found in the cytoplasm of cells of adipocyte differentiation. In this study, we examined a large number of soft tissue tumours with a commercial polyclonal anti-aP2/FABP4 antibody and a newly developed mouse monoclonal antibody raised against this protein to determine the diagnostic utility of aP2/FABP4 as a marker of tumours of adipose differentiation. A mouse monoclonal antibody, clone 175d, was raised against a mixture of synthetic peptides corresponding to the amino acid sequence of residues 10-28 and 121-132 of the human aP2/FABP4 protein. Antigen expression with polyclonal and monoclonal antibodies was immunohistochemically determined in paraffin sections of normal adipose tissue and a wide range of benign and malignant primary soft tissue tumours (n = 200). aP2/FABP4 was expressed around the cytoplasmic lipid vacuole in white and brown fat cells in benign lipomas and hibernomas. Immature fat cells and lipoblasts in spindle cell/pleomorphic lipoma, atypical lipomatous tumour/well-differentiated liposarcoma, myxoid/round cell liposarcoma and pleomorphic liposarcoma also reacted strongly for aP2/FABP4. No specific staining was seen in non-adipose benign and malignant mesenchymal and non-mesenchymal tumours. aP2/FABP4 is expressed by mature and immature fat cells and is a marker of tumours of adipose differentiation. Immunophenotypic aP2/FABP4 expression is useful in identifying lipoblasts, and immunohistochemistry with polyclonal/monoclonal anti-aP2/FABP4 antibodies should be useful in distinguishing liposarcoma from other malignancies, particularly round cell, myxoid and pleomorphic soft tissue sarcomas.


Assuntos
Proteínas de Ligação a Ácido Graxo/análise , Neoplasias de Tecidos Moles/diagnóstico , Animais , Feminino , Humanos , Imuno-Histoquímica , Lipoma/química , Lipossarcoma/química , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias de Tecidos Moles/química , Neoplasias de Tecidos Moles/patologia
7.
Eur J Cancer ; 46(3): 549-57, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20022486

RESUMO

Contrary findings exist according to the prognostic and predictive impact of thymidine phosphorylase (TP) expression in breast cancer. Goal of our study was to investigate TP expression on the mRNA level by microarray analysis in a large cohort of 1781 breast cancers and to analyse its prognostic impact. Furthermore we compared mRNA expression and immunohistochemical data to explain discrepancies between different studies. The prognostic value of TP mRNA expression was analysed among n=622 untreated patients. Strong expression in the subgroup of n=213 ER-negative cancer correlates with improved survival (P=0.012). In contrast, no difference in survival was detected in the ER-positive group. We also failed to observe a prognostic value of TP mRNA among n=435 endocrine-treated patients as well as n=111 CMF-treated patients. In an unsupervised analysis, TP clustered together with genes expressed in immune cells. Moreover, among normal tissues the highest TP mRNA expression was found in tissues of the immune system. The profile of TP expression in breast cancers correlates to a metagene of interferon induction whereas the expression of TP among normal tissues correlates to a metagene for macrophages. When comparing microarray data with immunohistochemistry from the same n=51 samples, there was no correlation with stained carcinoma cells. In contrast, the correlation with stromal staining was highly significant (P<0.001). Thus TP mRNA from microarray mainly reflects expression in stromal and immune cells. This could account for discrepant results from mRNA and IHC studies. In conclusion, the tumour infiltrating immune cells seem to be a major source of TP expression and predict a favourable prognosis in ER-negative breast cancer. Our data point to a role of TP in host immune response.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/enzimologia , Timidina Fosforilase/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/imunologia , Quimioterapia Adjuvante , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Técnicas Imunoenzimáticas , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Prognóstico , RNA Mensageiro/genética , RNA Neoplásico/genética , Análise de Sobrevida , Timidina Fosforilase/genética , Resultado do Tratamento
8.
Br J Cancer ; 101(10): 1749-57, 2009 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-19844231

RESUMO

BACKGROUND: Delta-like ligand 4 (Dll4) is a Notch ligand that is upregulated by hypoxia and vascular endothelial growth factor-A (VEGF-A) and is reported to have a role in tumor angiogenesis. Evidence from xenograft studies suggests that inhibiting Dll4-Notch signalling may overcome resistance to anti-VEGF therapy. The aim of this study was to characterise the expression of Dll4 in colon cancer and to assess whether it is associated with markers of hypoxia and prognosis. METHOD: In all, 177 colon cancers were represented in tissue microarrays. Immunohistochemistry was performed using validated antibodies against Dll4, VEGF, hypoxia-inducible factor (HIF)-1alpha, HIF-2alpha, prolyl hydroxylase (PHD)1, PHD2, PHD3 and carbonic anhydrase 9 (CA9). RESULTS: The expression of Dll4 was observed preferentially in the endothelium of 71% (125 out of 175) of colon cancers, but not in the endothelium adjacent to normal mucosa (none out of 107, P<0.0001). The expression of VEGF was significantly associated with HIF-2alpha (P<0.0001) and Dll4 (P=0.010). Only HIF-2alpha had a significant multivariate prognostic effect (hazard ratio 1.61, 95% confidence interval 1.01-2.57). Delta-like ligand 4 was also expressed by neoplastic cells, particularly neoplastic goblet cells. CONCLUSION: Endothelial expression of Dll4 is not a prognostic factor, but is significantly associated with VEGF. Assessing endothelial Dll4 expression may be critical in predicting response to anti-VEGF therapies.


Assuntos
Biomarcadores Tumorais/biossíntese , Neoplasias do Colo/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Proteínas Adaptadoras de Transdução de Sinal , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Proteínas de Ligação ao Cálcio , Hipóxia Celular/fisiologia , Neoplasias do Colo/irrigação sanguínea , Neoplasias do Colo/patologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Feminino , Células Caliciformes/metabolismo , Células Caliciformes/patologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Prognóstico , Taxa de Sobrevida , Fator A de Crescimento do Endotélio Vascular/biossíntese , Adulto Jovem
9.
Br J Cancer ; 100(10): 1666-73, 2009 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-19436307

RESUMO

The hypoxia-mediated response of tumours is a major determining factor in growth and metastasis. Understanding tumour biology under hypoxic conditions is crucial for the development of antiangiogenic therapy. Using one of the largest cohorts of rectal adenocarcinomas to date, this study investigated hypoxia-inducible factor-1alpha (HIF-1alpha) and HIF-2alpha protein expression in relation to rectal cancer recurrence and cancer-specific survival. Patients (n=90) who had undergone surgery for rectal adenocarcinoma, with no prior neoadjuvant therapy or metastatic disease, and for whom adequate follow-up data were available were selected. Microvessel density (MVD), HIF-1alpha and HIF-2alpha expressions were assessed immunohistologically with the CD34 antibody for vessel identification and the NB100-131B and NB100-132D3 antibodies for HIF-1alpha and HIF-2alpha, respectively. In a multifactorial analysis, results were correlated with tumour stage, recurrence rate and long-term survival. Microvessel density was higher across T and N stages (P<0.001) and associated with poor survival (hazard ratio (HR)=8.7, P<0.005) and decreased disease-free survival (HR=4.7, P<0.005). hypoxia-inducible factor-1alpha and -2alpha were expressed in >50% of rectal cancers (HIF-1alpha, 54%, 48/90; HIF-2alpha, 64%, 58/90). HIF-1alpha positivity was associated with both TNM stage (P<0.05) and vascular invasion (P<0.005). In contrast, no associations were demonstrated [corrected] between HIF-2alpha [corrected] and any pathological features or [corrected] outcome. The study showed an independent association between HIF-1alpha expression and advanced TNM stage with poor outcome. Our results indicate that HIF-1alpha, but not HIF-2alpha, might be used as a marker of prognosis, in addition to methods currently used, to enhance patient management.


Assuntos
Adenocarcinoma/diagnóstico , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Retais/diagnóstico , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Prognóstico , Neoplasias Retais/metabolismo , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Análise de Sobrevida
10.
Br J Cancer ; 100(2): 405-11, 2009 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-19165203

RESUMO

Basal-like tumours account for 15% of invasive breast carcinomas and are associated with a poorer prognosis and resistance to therapy. We hypothesised that this aggressive phenotype is because of an intrinsically elevated hypoxic response. Microarrayed tumours from 188 patients were stained for hypoxia-inducible factor (HIF)-1alpha, prolyl hydroxylase (PHD)1, PHD2, PHD3 and factor inhibiting HIF (FIH)-1, and carbonic anhydrase (CA) IX stained in 456 breast tumours. Tumour subtypes were correlated with standard clincopathological parameters as well as hypoxic markers. Out of 456 tumours 62 (14%) tumours were basal-like. These tumours were positively correlated with high tumour grade (P<0.001) and were associated with a significantly worse disease-free survival compared with luminal tumours (P<0.001). Fifty percent of basal-like tumours expressed HIF-1alpha, and more than half expressed at least one of the PHD enzymes and FIH-1. Basal-like tumours were nine times more likely to be associated with CAIX expression (P<0.001) in a multivariate analysis. Carbonic anhydrase IX expression was positively correlated with tumour size (P=0.005), tumour grade (P<0.001) and oestrogen receptor (ER) negativity (P<0.001). Patients with any CAIX-positive breast tumour phenotype and in the basal tumour group had a significantly worse prognosis than CAIX-negative tumours when treated with chemotherapy (P<0.001 and P=0.03, respectively). The association between basal phenotype and CAIX suggests that the more aggressive behaviour of these tumours is partly due to an enhanced hypoxic response. Further, the association with chemoresistance in CAIX-positive breast tumours and basal-like tumours in particular raises the possibility that targeted therapy against HIF pathway or downstream genes such as CAs may be an approach to investigate for these patients.


Assuntos
Antígenos de Neoplasias/metabolismo , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Anidrases Carbônicas/metabolismo , Resistencia a Medicamentos Antineoplásicos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Anidrase Carbônica IX , Dioxigenases/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Homeodomínio/metabolismo , Humanos , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Prolina Dioxigenases do Fator Induzível por Hipóxia , Técnicas Imunoenzimáticas , Pessoa de Meia-Idade , Oxigenases de Função Mista , Invasividade Neoplásica , Estadiamento de Neoplasias , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Prognóstico , Proteínas Repressoras/metabolismo , Taxa de Sobrevida , Fatores de Transcrição/metabolismo
11.
Pathol Res Pract ; 205(1): 1-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19008051

RESUMO

AIM: The mechanism by which neoplasias respond to hypoxia determines their biological behavior and prognosis. Understanding the biology of tumors under hypoxic conditions is crucial for the development of anti-angiogenic therapy. Using the largest cohort of rectal adenocarcinomas to date, this study aimed to assess microvessel density (MVD) and carbonic anhydrase-9 (CA-9) expression and to correlate the results with recurrence and cancer-specific survival. MATERIALS AND METHODS: Patients (n=101) who underwent surgery for rectal adenocarcinoma without previous neoadjuvant therapy or metastatic disease were selected. MVD and CA-9 expression were assessed immunohistologically by using the CD34 antibody and the MN/CA9 M75 antibody, respectively. In a multifactorial analysis, the results were correlated with tumor stage, recurrence rate, and long-term survival. RESULTS: MVD was higher with increased T- and N-stages (p<0.01) and associated positively with poor survival (hazard ratio (HR) 1.3 per 10 vessel increase, p<0.01). CA-9 was expressed in 73% of cancers. Negative lymph node status correlated with CA-9 positivity (p<0.05), reflected in a higher rate of CA-9 positivity in earlier Dukes' stages (p<0.05). CA-9 positivity across tumor node metastasis (TNM) stages approached significance (Stage I/II: 80% CA-9 positive vs. 20% CA-9 negative; Stage III: 63% CA-9 positive vs. 37% negative, p=0.051). A trend was seen towards better cancer-specific survival in patients with CA-9 positive carcinomas (HR 0.51, p=0.07) on univariate analysis. DISCUSSION: MVD was higher in more advanced T- and N-stages and may be used as a determinant of survival in patients with rectal adenocarcinomas. CA-9 expression was seen more often in earlier Dukes' stages, possibly representing an early tumor hypoxic response. CA-9 expression by adenocarcinoma cells may confer long-term survival advantage in surgically treated rectal cancer.


Assuntos
Adenocarcinoma/irrigação sanguínea , Adenocarcinoma/enzimologia , Antígenos de Neoplasias/análise , Biomarcadores Tumorais/análise , Anidrases Carbônicas/análise , Microvasos/patologia , Neoplasias Retais/irrigação sanguínea , Neoplasias Retais/enzimologia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso , Anidrase Carbônica IX , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Recidiva , Medição de Risco , Fatores de Tempo , Resultado do Tratamento
12.
Br J Cancer ; 97(9): 1277-86, 2007 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-17923874

RESUMO

The purpose of this study is to investigate the associations of microvessel density (MVD) and other pathological variables with survival, and whether they accounted for survival differences between Japanese and British patients. One hundred seventy-three Japanese and 184 British patients were included in the study. British patients were significantly older (56.3+/-11.4 years vs 52.5+/-12.9 years; P<0.01) and had smaller tumours (2.2+/-1.3 vs 2.7+/-1.8 cm; P<0.01), which were more frequently oestrogen receptor positive (78.8 vs 57.2%, P<0.01), had more grade III tumours (29.9 vs 21.4%, P=0.04) and more infiltrating lobular carcinomas (13.6 vs 4.0%, P<0.01) and a higher MVD compared with Japanese patients (57.9+/-19.8 vs 53.2+/-18.6; P=0.01). However, no difference in the prevalence of lymph-node metastasis was found between them (39.1 vs 37.5%, P=0.75). Younger British patients (age <50 years) had the highest MVD compared with Japanese and older British patients (P<0.01). Japanese patients were proportionately more likely to receive chemotherapy than endocrine therapy (P<0.01). British patients had a significantly worse relapse-free survival and overall survival compared with Japanese patients, after statistical adjustment for variables (hazard ratio=2.1, 2.4, P<0.01, P<0.01, respectively), especially, in T2 stage, low MVD and older subgroup (HR: 3.6, 5.0; 3.1, 3.3; 3.2, 3.9, respectively), but only in ER negative cases (P=0.04, P=0.01, respectively). The present study shows that MVD contributes to the Japanese-British disparity in breast cancer. However, the MVD variability did not explain the survival differences between Japanese and British patients.


Assuntos
Neoplasias da Mama/irrigação sanguínea , Neovascularização Patológica/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Neoplasias da Mama/terapia , Quimioterapia Adjuvante , Terapia Combinada , Feminino , Humanos , Japão , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Taxa de Sobrevida , Resultado do Tratamento , Reino Unido
13.
Eur J Clin Invest ; 37(11): 878-86, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17883421

RESUMO

BACKGROUND: Vascular endothelial cell growth factor (VEGF) acts by phosphorylating specific tyrosine kinase receptors on endothelial cell membrane promoting angiogenesis. The study of the activation status of VEGF receptors in human malignancies has recently become feasible by means of specific monoclonal antibodies recognising the phosphorylated form of these receptors. MATERIALS AND METHODS: In the current study, we investigate the expression of the phosphorylated VEGFR2/KDR receptor in normal colon and colorectal adenocarcinomas in parallel with histopathological parameters, prognosis and the expression of the 'hypoxia inducible factor' HIF1alpha. RESULTS: pVEGFR2/KDR was weakly expressed in the normal colon, but it was expressed strongly in the cytoplasm and nuclei of cancer cells and in the tumour associated vasculature, mainly at the invading tumour edge. pVEGFR2/KDR expression in cancer cells was significantly associated with a tumour diameter > 6 cm (P = 0.04), poor histological differentiation (P = 0.004) and with high CEF1alpha expression (P = 0.05). High pVEGFR2/KDR expressing vascular density was significantly related with a high VEGF and HIF1alpha expression in cancer cells (P = 0.02 and 0.03, respectively). This was also related significantly to high pVEGFR2/KDR expression in cancer cells. In multivariate analysis, the most significant predictors for death were lympho-vascular invasion (P < 0.001) followed by VEGF (P = 0.014), node status (P = 0.015), standard vascular density (P = 0.022) and necrosis (P = 0.032). CONCLUSIONS: pVEGFR2 receptors are largely expressed in colon cancer cells and intratumoural vasculature. As VEGF targeting agents enter the clinical practice, the role of monoclonal antibodies recognising the phosphorylated form of VEGF receptors as predictors of response to targeted therapies should be sought in clinicopathological trials.


Assuntos
Adenocarcinoma/metabolismo , Diferenciação Celular/fisiologia , Neoplasias Colorretais/diagnóstico , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/mortalidade , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Taxa de Sobrevida
14.
J Pathol ; 212(3): 335-44, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17487938

RESUMO

Thymidine phosphorylase (TP) is an angiogenic enzyme, catalysing the reversible phosphorylation of thymidine to thymine and 2-deoxyribose. TP is up-regulated in neoplasia, being associated with advanced tumour stage, microvessel density and prognosis in several tumour types. Although TP is a non-mitogenic migratory factor for endothelium, the mechanism by which TP mediates these effects is still unclear. We compared the gene expression profile of endothelial cells grown in vitro in the presence or absence of TP by cDNA microarray analysis. To determine the time-course of TP angiogenic induction, endothelial cells were stimulated with TP (10 ng/ml) for 5 and 18 h. Gene expression levels of Tie2, angiopoietin (Ang)1 and Ang2, measured by RNase protection assay (RPA), showed maximal alteration at 18 h. cDNA from human umbilical vein endothelial cells (HUVEC) grown for 18 h in the presence or absence of TP (10 ng/ml) was hybridized to a human cDNA cytokine array representing 375 angiogenic genes. Significantly altered expression occurred in 89 human angiogenic genes (72 genes were up-regulated and 17 down-regulated). Changes in five genes relevant to vascular remodelling biology (Tie2, nNos, P-selectin, ephrin-B1 and TP) were validated in triplicate experiments by real-time RT-PCR. But only P-selectin gene expression remained significant. Correlation between P-selectin and TP was assessed by immunohistochemistry on 161 human breast cancers, using human tissue microarray. Tumour cell TP correlated with tumour cell P-selectin but not with endothelial cell P-selectin. These data show that TP stimulates changes in mRNA expression maximally after 18 h culture in vitro. It confirms a role for TP in vascular remodelling involving several classes of genes, including the cell adhesion molecule, P-selectin. Although confirmation of the role of TP-mediated cell adhesion molecule (CAM) induction is required; however, this pathway may provide an attractive therapeutic target, since it is likely to affect several important tumour processes, including angiogenesis and metastasis.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Células Endoteliais/metabolismo , Regulação Neoplásica da Expressão Gênica , Selectina-P/metabolismo , Timidina Fosforilase/metabolismo , Sequência de Bases , Neoplasias da Mama/química , Carcinoma Ductal de Mama/química , Primers do DNA/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização In Situ/métodos , Dados de Sequência Molecular , Neovascularização Patológica/genética , Análise de Sequência com Séries de Oligonucleotídeos , Selectina-P/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Timidina Fosforilase/análise
15.
Histopathology ; 50(5): 555-60, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17394490

RESUMO

AIMS: To investigate the role of BNIP3, a 19-kDa interacting protein of the Bcl-2 family, alongside Bcl-2 in follicular lymphoma in comparison with reactive lymphoid hyperplasia. The results were compared with those from p53 and caspase-3 (apoptotic markers) and Ki67 (proliferation marker). METHODS AND RESULTS: Immunohistochemistry using monoclonal antibodies showed BNIP3 to be strongly expressed in most follicular lymphomas but to be weak to negative in all of the reactive cases. There was also an inverse relationship with Bcl-2 expression. There was no correlation of BNIP3 immunoreactivity with proliferation and caspase and p53 were virtually negative in all follicular lymphomas and reactive lymphoid cases. CONCLUSIONS: BNIP3 is strongly expressed in most follicular lymphomas, especially those that are Bcl-2 negative. BNIP3 may serve as a marker of more aggressive behaviour in follicular lymphoma and be useful diagnostically in the distinction from reactive lymphadenitis.


Assuntos
Linfoma Folicular/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Diagnóstico Diferencial , Feminino , Humanos , Linfadenite/diagnóstico , Linfadenite/metabolismo , Linfoma Folicular/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
16.
Oncogene ; 26(1): 132-41, 2007 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-16799636

RESUMO

Hypoxia, via the hypoxia-inducible factors 1 and 2 (HIF-1 and HIF-2), upregulates many genes involved in cell survival. However, proapoptotic pathways are also induced. BCL-2/adenovirus E1B-19 kDa-interacting protein 3 (BNIP3) represents a paradigm of a cell death protein that is hypoxically upregulated via HIF-1 in most cancers. We found that in contrast to many other cell types, 6/8 colorectal cancer (CRC) cell lines show little hypoxic induction of BNIP3 despite an intact HIF signalling system. Colorectal tumour tissue also loses BNIP3 expression relative to matched normal samples. Downregulation of hypoxic BNIP3 in CRC cells was independent of the expression of other BCL-2 family members, or BNIP3L. That BNIP3 plays a functional role in hypoxic survival in CRC cells was demonstrated by the fact that CRC cell lines that do not upregulate BNIP3 or have been treated with BNIP3 RNA interference were insensitive to hypoxia-induced cell death. Promoter methylation and histone deacetylation were shown to silence BNIP3 in these CRC cell lines. Of significance, hypoxic induction of BNIP3 was restored in 4/6 cell lines by trichostatin-A treatment alone. These data suggest that BNIP3 plays an important role in hypoxic cell death and epigenetic mechanisms selectively silence its expression in CRC.


Assuntos
Neoplasias Colorretais/genética , Metilação de DNA , Inativação Gênica , Histonas/metabolismo , Proteínas de Membrana/genética , Proteínas Proto-Oncogênicas/genética , Acetilação , Sequência de Bases , Western Blotting , Morte Celular/genética , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Neoplasias Colorretais/patologia , Humanos , Reação em Cadeia da Polimerase , RNA Interferente Pequeno , Transdução de Sinais
17.
Histopathology ; 47(6): 602-10, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16324198

RESUMO

AIMS: The cellular response to hypoxia includes the hypoxia inducible factor (HIF)-induced transcription of genes involved in diverse processes such as glycolysis, angiogenesis and the growth of experimental tumours. Regulation of the level of hypoxia inducible factors 1alpha and 2alpha (HIF-1alpha and HIF-2alpha) is a primary determinant of HIF activity. Recent biochemical and candidate gene approach studies have led to the discovery of three HIF-regulatory prolyl hydroxylases, PHD-1, -2 and -3 and an asparaginyl hydroxylase, also known as FIH (factor inhibiting HIF). In this study, we raised and characterized monoclonal antibodies against PHD-1, PHD-2, PHD-3 and FIH. METHODS AND RESULTS: Immunohistochemistry of normal tissues with these monoclonal antibodies demonstrated a wide distribution in epithelial cells, stromal cells and leucocytes, with cytoplasmic staining predominating over nuclear staining. A preliminary study of tumours showed variable staining in tumour, stromal and inflammatory cells. While all tumour types showed some positive staining with each antibody, the overall pattern suggested a slight decrease in the amount of staining seen with PHD-1, -2 and -3 and an increase in FIH staining in neoplasia compared with corresponding normal tissues. CONCLUSIONS: These monoclonal antibodies will allow further larger scale studies to determine the significance of PHD and FIH expression in neoplasia.


Assuntos
Anticorpos Monoclonais/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas Imediatamente Precoces/metabolismo , Neoplasias/metabolismo , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Animais , Células COS , Linhagem Celular , Linhagem Celular Tumoral , Chlorocebus aethiops , Dioxigenases , Humanos , Prolina Dioxigenases do Fator Induzível por Hipóxia , Imuno-Histoquímica , Oxigenases de Função Mista , Neoplasias/genética , Neoplasias/patologia , Distribuição Tecidual
18.
Br J Cancer ; 93(10): 1128-36, 2005 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-16251878

RESUMO

Hypoxia and angiogenesis are important factors in breast cancer progression. Little is known of hypoxia and angiogenesis in lymph node metastases of breast cancer. The aim of this study was to quantify hypoxia, by hypoxia-induced marker expression levels, and angiogenesis, by endothelial cell proliferation, comparing primary breast tumours and axillary lymph node metastases. Tissue sections of the primary tumour and a lymph node metastasis of 60 patients with breast cancer were immunohistochemically stained for the hypoxia-markers carbonic anhydrase 9 (CA9), hypoxia-inducible factor-1alpha (Hif-1alpha) and DEC-1 and for CD34/Ki-67. Endothelial cell proliferation fraction (ECP%) and tumour cell proliferation fraction (TCP%) were assessed. On haematoxylin-eosin stain, the growth pattern and the presence of a fibrotic focus were assessed. Hypoxia-marker expression, ECP% and TCP% in primary tumours and in lymph node metastases were correlated to each other and to clinico-pathological variables. Median ECP% and TCP% in primary tumours and lymph node metastases were comparable (primary tumours: ECP%=4.02, TCP%=19.54; lymph node metastases: ECP%=5.47, TCP%=21.26). ECP% correlated with TCP% (primary tumours: r=0.63, P<0.001; lymph node metastases: r=0.76, P<0.001). CA9 and Hif-1alpha expression were correlated (primary tumours P=0.005; lymph node metastases P<0.001). In primary tumours, CA9 and Hif-1alpha expression were correlated with DEC-1 expression (P=0.05), presence of a fibrotic focus (P<0.007) and mixed/expansive growth pattern (P<0.001). Primary tumours and lymph node metastases with CA9 or Hif-1alpha expression had a higher ECP% and TCP% (P<0.003); in primary tumours, mixed/expansive growth pattern and fibrotic focus were characterised by higher ECP% (P=0.03). Furthermore, between primary tumours and lymph node metastases a correlation was found for ECP%, TCP%, CA9 and Hif-1alpha expression (ECP% r=0.51, P<0.001; TCP r=0.77, P<0.001; CA9 and Hif-1alpha P<0.001). Our data demonstrate that the growth of breast cancer lymph node metastases is angiogenesis dependent and that angiogenesis and hypoxia in the primary tumour predict angiogenesis and hypoxia in the lymph node metastases. Together with previous findings in breast cancer liver metastases, which grow in 96% of cases angiogenesis independently, these data suggest that both the intrinsic growth characteristics and angiogenic potential of breast cancer cells and the site-specific tumour microenvironment determine angiogenesis and hypoxia in breast cancer.


Assuntos
Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/patologia , Hipóxia Celular , Metástase Linfática/patologia , Neovascularização Patológica , Adulto , Idoso , Idoso de 80 Anos ou mais , Proliferação de Células , Humanos , Pessoa de Meia-Idade
19.
Histopathology ; 46(6): 668-76, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15910598

RESUMO

AIMS: To study the expression of hypoxia-regulated markers in pancreatic ductal adenocarcinomas (PA) in relationship to the presence of a fibrotic focus, angiogenesis quantification and clinical outcome. METHODS AND RESULTS: The expression of hypoxia-inducible factor (HIF)-1alpha, HIF-2alpha, carbonic anhydrase 9 (CA9) and vascular endothelial growth factor (VEGF) was immunohistochemically detected in 50 PA and correlated with tumour characteristics, microvascular density (MVD) and survival. HIF-1alpha was expressed within tumour cells in 68%, HIF-2alpha in 46%, CA9 in 78% and VEGF in 52% of the cases. Stromal expression was also noted for HIF-2alpha and CA9 in, respectively, 42% and 48% of the cases. Tumour CA9 expression was associated with that of VEGF (P=0.004) and that of stromal HIF-2alpha (P=0.013), with the presence of a fibrotic focus (P=0.046) and with an increased MVD (P=0.034). Tumour VEGF expression correlated with the presence of a fibrotic focus (P=0.039) and a greater MVD (P=0.047). Both the presence of a fibrotic focus (P=0.0002) and high tumour CA9 expression (P=0.029) were associated with reduced overall survival. CONCLUSION: The strong association of the presence of a fibrotic focus with CA9 expression and lower survival demonstrates that hypoxia-driven angiogenesis plays an important role in the progression of PA.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma Ductal Pancreático/patologia , Hipóxia/fisiopatologia , Neovascularização Patológica/patologia , Neoplasias Pancreáticas/patologia , Adulto , Idoso , Antígenos de Neoplasias/análise , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Anidrase Carbônica IX , Anidrases Carbônicas/análise , Carcinoma Ductal Pancreático/irrigação sanguínea , Carcinoma Ductal Pancreático/metabolismo , Feminino , Fibrose , Seguimentos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia , Imuno-Histoquímica , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Necrose , Estadiamento de Neoplasias , Neovascularização Patológica/metabolismo , Pâncreas/irrigação sanguínea , Pâncreas/química , Pâncreas/patologia , Neoplasias Pancreáticas/irrigação sanguínea , Neoplasias Pancreáticas/metabolismo , Análise de Sobrevida , Fatores de Transcrição/análise , Fator A de Crescimento do Endotélio Vascular/análise
20.
Histopathology ; 46(2): 209-16, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15693894

RESUMO

AIMS: To study the expression of phosphorylated vascular endothelial growth factor receptor 2 (VEGFR2), a membrane-bound tyrosine kinase receptor to vascular endothelial growth factor, in lymphoma and non-neoplastic lymphadenopathy. METHODS AND RESULTS: Archival cases (89 cases of lymphoma and 17 cases of non-neoplastic lymphadenopathy) were studied immunohistochemically with three monoclonal antibodies to the different autophosphorylation sites in the cytoplasmic tail of the receptor. There was increased expression of this receptor in lymphoma and particularly in all cases of peripheral T-cell lymphoma. In this category, there was nuclear re-location of this receptor. CONCLUSIONS: This very interesting finding raises the possibility that VEGFR2 may be involved in the transcriptional regulation of this disease. Small molecule inhibitors to this receptor may therefore be a useful adjunct in the therapy of this disease.


Assuntos
Doenças Linfáticas/patologia , Linfoma/patologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Humanos , Imuno-Histoquímica , Doenças Linfáticas/metabolismo , Linfoma/metabolismo , Linfoma de Células B/metabolismo , Linfoma de Células B/patologia , Linfoma de Células T/metabolismo , Linfoma de Células T/patologia , Microscopia Confocal , Fosforilação
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