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1.
Int J Surg Case Rep ; 67: 82-85, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32044563

RESUMO

INTRODUCTION: Deep pelvic lymph node dissection for cancer may result in incisional inguinal hernias. We present a case report of successful laparoscopic trans-peritoneal repair of a large ventral inguinal hernia that developed following ileo-inguinal lymph node dissection (CLND) for melanoma. CASE PRESENTATION: A successful 3 port laparoscopic trans-peritoneal procedure was performed on a 56-year-old female for the repair of a left inguinal hernia, developed 13 months following CLND for melanoma. The large oval 18 × 14 cm inguinal defect, with superior margins bordering the conjoint tendon and inferior margins bordering the ileo-psoas muscle, femoral vessels and nerve, was not closed in order to avoid excessive tension and was repaired by fixing a 25 × 20 cm intra-peritoneal mesh to abdominal borders at superior and lateral margins with permanent fasteners and at the inferior margin by a cyanoacrylate-glued overlap to protect femoral vessels and nerves from damage. No hernia recurrence was observed 8 months following this procedure. DISCUSSION: Incisional inguinal hernias, following CLND, are rare but present a challenge to surgeons due to the difficulty in identifying both anatomical plains and safe sites for stable repair. CONCLUSIONS: We report a laparoscopic trans-peritoneal approach for the safe, reproducible and efficacious repair of incisional inguinal hernias that result from CLND. In our opinion prevention of hernia recurrence can be achieved by a intraperitoneal large mesh fixed at superior and lateral margin borders with permanent fasteners and using cyanoacrylate glue to overlap inferior margin borders in order to prevent vessels and/or nerve injury.

2.
Int J Surg Case Rep ; 61: 4-8, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31302319

RESUMO

INTRODUCTION: Merkel cell carcinoma (MCC) is a rare, neuroendocrine skin tumor, with high frequency of locoregional recurrence, metastases, and poor prognosis. Locoregional MCC recurrence in the extremities can pose considerable treatment challenges. We report a case of long-term survival in a female patient with recurrent MCC of the leg, treated with surgery and locoregional chemotherapy. PRESENTATION OF CASE: A 73-year-old female with cirrhosis and hepatitis C, developed cutaneous MCC in the left inferior limb. This patient initially received surgical treatment, with subsequent negative sentinel lymph-node biopsy in another center, one-month prior recovery in our department, and arrived with 4 new limb nodules, cranially to the previously treated area, without distant metastases or inguinal lymph node recurrence. This patient was not eligible for immunotherapy due to active hepatitis upon treatment with NS5B inhibitors, or eligible for systemic chemotherapy or radiotherapy due to severe neutropenia and was, therefore, subjected to surgical resection combined with Isolated Pelvic and Limb Perfusion (IPLP) with Melphalan. Histological evaluation confirmed MCC diagnosis and during the following 4 months, she developed further locoregional recurrences with homolateral inguinal lymph node involvement and was subjected to two additional rounds of surgery plus IPLP. DISCUSSION: All procedures were tolerated, systemic toxicities were temporary and subsequent clinical and radiological follow-up, following the last combined treatment, indicated that this patient was still alive and disease-free, at 56 months. CONCLUSION: In this case, surgery combined with locoregional Melphalan chemotherapy was an effective and repeatable treatment for recurrent MMC and resulted in unexpected long-term survival.

3.
J Public Health (Oxf) ; 41(3): 527-534, 2019 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-30239914

RESUMO

BACKGROUND: Driving is a common type of sedentary behaviour; an independent risk factor for poor health. The study explores whether driving is also associated with other unhealthy lifestyle factors. METHODS: In a cross-sectional study of UK Biobank participants, driving time was treated as an ordinal variable and other lifestyle factors dichotomized into low/high risk based on guidelines. The associations were explored using chi-square tests for trend and binary logistic regression. RESULTS: Of the 386 493 participants who drove, 153 717 (39.8%) drove <1 h/day; 140 140 (36.3%) 1 h/day; 60 973 (15.8%) 2 h/day; and 31 663 (8.2%) ≥3 h/day. Following adjustment for potential confounders, driving ≥3 h/day was associated with being overweight/obese (OR = 1.74, 95% CI: 1.64-1.85), smoking (OR = 1.48, 95% CI: 1.37-1.63), insufficient sleep (1.70, 95% CI: 1.61-1.80), low fruit/vegetable intake (OR = 1.26, 95% CI: 1.18-1.35) and low physical activity (OR = 1.05, 95% CI: 1.00-1.11), with dose relationships for the first three, but was not associated with higher alcohol consumption (OR = 0.94, 95% CI: 0.87-1.02). CONCLUSIONS: Sedentary behaviour, such as driving, is known to have an independent association with adverse health outcomes. It may have additional impact mediated through its effect on other aspects of lifestyle. People with long driving times are at higher risk and might benefit from targeted interventions.


Assuntos
Condução de Veículo/psicologia , Condução de Veículo/estatística & dados numéricos , Comportamentos Relacionados com a Saúde , Estilo de Vida , Comportamento Sedentário , Adulto , Idoso , Bancos de Espécimes Biológicos , Estudos Transversais , Exercício Físico/psicologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Sobrepeso/epidemiologia , Fatores de Risco , Fumar/epidemiologia , Reino Unido/epidemiologia
4.
Cell Death Discov ; 2: 16004, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27551499

RESUMO

We report a novel pro-apoptotic function for nerve growth factor (NGF) and its tropomyosin-related kinase A (TrkA) receptor in sensitizing TRAIL (TNF-related apoptotis-inducing ligand)-resistant SH-SY5Y neuroblastoma (NB) cells to TRAIL-induced apoptosis, resulting in the abrogation of anchorage-independent tumourigenic growth in vitro. We show that the TRAIL-resistant SH-SY5Y phenotype is cFLIP (cellular FLICE-like inhibitory protein) dependent and not due to low-level functional TRAIL receptor or caspase expression or an inhibitory equilibrium between functional and decoy TRAIL receptors or B-cell lymphoma 2 (Bcl-2) and BH3-only (Bcl-2 homology domain 3-only) family proteins. NGF sensitization of SH-SY5Y cells to TRAIL-induced apoptosis was dependent upon TrkA expression, activation and subsequent sequestration of cFLIP. This reduces cFLIP recruitment to TRAIL-activated death receptors and increases the recruitment of caspase-8, leading to TRAIL-induced, caspase-dependent, type II apoptosis via the intrinsic mitochondrial pathway. This effect was temporary, inhibited within 6 h by nuclear factor-κ binding (NF-κB)-mediated increase in myeloid cell leukaemia-1 (Mcl-1) expression, abrogated by transient cFLIP or B-cell lymphoma-extra large (Bcl-xL) overexpression and optimized by NF-κB and Mcl-1 inhibitors. This novel mechanism adds an important pro-apoptotic immunological dimension to NGF/TrkA interaction that may not only help to explain the association between TrkA expression, better prognosis and spontaneous remission in NB, but also provides a novel potential pro-apoptotic therapeutic use for NGF, TRAIL and inhibitors of NF-κB and/or Mcl-1 in favourable and unfavourable NBs that express TrkA and exhibit cFLIP-mediated TRAIL resistance.

6.
Oncogene ; 33(8): 966-76, 2014 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-23474757

RESUMO

The gene encoding the receptor tyrosine kinase ERBB2, also known as HER2, is amplified and/or overexpressed in up to 15% of breast cancers. These tumours are characterised by an aggressive phenotype and poor clinical outcome. Although therapies targeted at ERBB2 have proven effective, many patients fail to respond to treatment or become resistant and the reasons for this are still largely unknown. Using a high-throughput functional screen we assessed whether genes found to be recurrently amplified and overexpressed in ERBB2+ve breast cancers mediate resistance to the ERBB2-targeted agent lapatinib. Lapatinib-resistant ERBB2-amplified breast cancer cell lines were screened, in the presence or absence of lapatinib, with an RNA interference library targeting 369 genes recurrently amplified and overexpressed in both ERBB2-amplified breast cancer tumours and cell lines. Small interfering RNAs targeting a number of genes caused sensitivity to lapatinib in this context. The mechanisms of resistance conferred by the identified genes were further investigated and in the case of NIBP (TRAPPC9), lapatinib resistance was found to be mediated through NF-κB signalling. Our results indicate that specific amplified and/ or overexpressed genes found in ERBB2-amplified breast cancer may mediate response to ERBB2-targeting agents.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Genes erbB-2 , Quinazolinas/farmacologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Ensaios de Triagem em Larga Escala , Humanos , Lapatinib , Interferência de RNA , RNA Interferente Pequeno/genética
7.
Oncogene ; 33(5): 619-31, 2014 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-23334330

RESUMO

Overexpression of the receptor tyrosine kinase ERBB2 (also known as HER2) occurs in around 15% of breast cancers and is driven by amplification of the ERBB2 gene. ERBB2 amplification is a marker of poor prognosis, and although anti-ERBB2-targeted therapies have shown significant clinical benefit, de novo and acquired resistance remains an important problem. Genomic profiling has demonstrated that ERBB2+ve breast cancers are distinguished from ER+ve and 'triple-negative' breast cancers by harbouring not only the ERBB2 amplification on 17q12, but also a number of co-amplified genes on 17q12 and amplification events on other chromosomes. Some of these genes may have important roles in influencing clinical outcome, and could represent genetic dependencies in ERBB2+ve cancers and therefore potential therapeutic targets. Here, we describe an integrated genomic, gene expression and functional analysis to determine whether the genes present within amplicons are critical for the survival of ERBB2+ve breast tumour cells. We show that only a fraction of the ERBB2-amplified breast tumour lines are truly addicted to the ERBB2 oncogene at the mRNA level and display a heterogeneous set of additional genetic dependencies. These include an addiction to the transcription factor gene TFAP2C when it is amplified and overexpressed, suggesting that TFAP2C represents a genetic dependency in some ERBB2+ve breast cancer cells.


Assuntos
Neoplasias da Mama/genética , Amplificação de Genes/genética , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Fator de Transcrição AP-2/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Feminino , Perfilação da Expressão Gênica , Humanos , Células MCF-7 , Interferência de RNA , RNA Interferente Pequeno , Receptor ErbB-2/biossíntese , Fator de Transcrição AP-2/biossíntese
8.
Oncogene ; 30(41): 4243-60, 2011 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-21552290

RESUMO

Individuals with germline mutations in the tumour-suppressor gene CYLD are at high risk of developing disfiguring cutaneous appendageal tumours, the defining tumour being the highly organised cylindroma. Here, we analysed CYLD mutant tumour genomes by array comparative genomic hybridisation and gene expression microarray analysis. CYLD mutant tumours were characterised by an absence of copy-number aberrations apart from LOH chromosome 16q, the genomic location of the CYLD gene. Gene expression profiling of CYLD mutant tumours showed dysregulated tropomyosin kinase (TRK) signalling, with overexpression of TRKB and TRKC in tumours when compared with perilesional skin. Immunohistochemical analysis of a tumour microarray showed strong membranous TRKB and TRKC staining in cylindromas, as well as elevated levels of ERK phosphorylation and BCL2 expression. Membranous TRKC overexpression was also observed in 70% of sporadic BCCs. RNA interference-mediated silencing of TRKB and TRKC, as well as treatment with the small-molecule TRK inhibitor lestaurtinib, reduced colony formation and proliferation in 3D primary cell cultures established from CYLD mutant tumours. These results suggest that TRK inhibition could be used as a strategy to treat tumours with loss of functional CYLD.


Assuntos
Neoplasias/genética , Proteínas Quinases/genética , Transdução de Sinais/genética , Proteínas Supressoras de Tumor/genética , Adenoma de Glândula Sudorípara/genética , Adenoma de Glândula Sudorípara/metabolismo , Adenoma de Glândula Sudorípara/patologia , Carbazóis/farmacologia , Carcinoma Adenoide Cístico/genética , Carcinoma Adenoide Cístico/metabolismo , Carcinoma Adenoide Cístico/patologia , Análise por Conglomerados , Hibridização Genômica Comparativa , Enzima Desubiquitinante CYLD , Furanos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Immunoblotting , Imuno-Histoquímica , Mutação , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasia de Células Basais/genética , Neoplasia de Células Basais/metabolismo , Neoplasia de Células Basais/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Cultura Primária de Células , Proteínas Quinases/metabolismo , Interferência de RNA , Receptor trkB/antagonistas & inibidores , Receptor trkB/genética , Receptor trkB/metabolismo , Receptor trkC/antagonistas & inibidores , Receptor trkC/genética , Receptor trkC/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias das Glândulas Sudoríparas/genética , Neoplasias das Glândulas Sudoríparas/metabolismo , Neoplasias das Glândulas Sudoríparas/patologia , Análise Serial de Tecidos , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor/metabolismo
9.
J Vet Intern Med ; 25(3): 497-503, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21418324

RESUMO

BACKGROUND: Hemangiosarcoma (HSA) is a common malignancy of dogs with characteristic early, aggressive metastasis. Diagnosis of HSA is challenging because of lack of sensitive and specific diagnostic tests. HYPOTHESIS: Specific proteins that are increased in serum of dogs with HSA might represent useful biomarkers of the disease. ANIMALS: Thirty-four dogs with HSA and 42 healthy dogs from the Ontario Veterinary College Teaching Hospital. METHODS: This case-control study compared serum proteins in dogs with HSA and healthy dogs. Proteins were separated by 2-dimensional difference gel electrophoresis and identified by liquid chromatography and tandem mass spectrometry. RESULTS: Western blot analysis showed that serum collagen XXVII peptide concentration in serum of dogs with large metastatic HSA burdens (1,488, 231-3,754 DU; median, minimum-maximum); was, on average, 9.5-fold higher than in healthy dogs (156; 46-2,101 DU). While concentrations for dogs with osteosarcomas (678; 124-3,251 DU), lymphomas (423; 92-2,777 DU), carcinomas (1,022; 177-3,448 DU), and inflammatory disease were also increased, values were consistently lower than those for HSA. Receiver operating characteristic curves revealed an estimated area under the curve of 83% for HSA cases whereas areas for other neoplastic and nonneoplastic diseases were nondiscriminatory. Serum collagen XXVII peptide concentration before splenectomy (1,350; 1,156-1,929 DU) was reduced after tumor removal (529; 452-562 DU) and chemotherapy but increased in 2 dogs with tumor recurrence (511-945 DU; 493-650 DU). CONCLUSIONS AND CLINICAL IMPORTANCE: Collagen XXVII peptide might be useful for diagnosis and monitoring of advanced HSA.


Assuntos
Doenças do Cão/sangue , Colágenos Fibrilares/química , Hemangiossarcoma/veterinária , Lipocalinas/sangue , Lipocalinas/química , Sequência de Aminoácidos , Animais , Biomarcadores , Estudos de Casos e Controles , Cães , Colágenos Fibrilares/sangue , Hemangiossarcoma/sangue , Hemangiossarcoma/metabolismo , Proteômica , Sensibilidade e Especificidade
10.
Artigo em Inglês | MEDLINE | ID: mdl-22255136

RESUMO

Highly sensitive and selective biomarker detection is required for early detection of hepatocellular carcinoma (HCC). Disease progression has been shown to correlate with specific fucosylation of a validated HCC serum glycoprotein biomarker, alpha-fetoprotein (AFP) Carbohydrate binding proteins, such as lectins, can be used as diagnostic indicators for monitoring glycosylation changes during disease progression in hepatitis B virus (HBV) or hepatitis C virus (HCV) infected patients. We prepared surface-enhanced Raman spectroscopy (SERS) substrates, which provide controllable, well-organized nanoparticles on the surface, for the analysis of a fucose binding lectin AAL. The SERS based assay provides fast (<10 s), and reproducible (<5% variation) detection.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Glicosilação , Humanos , Sensibilidade e Especificidade , Análise Espectral Raman
11.
Mult Scler ; 16(6): 670-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20558500

RESUMO

BACKGROUND: Spinal cord involvement in multiple sclerosis (MS) is common and an important element in disability. Previous studies demonstrated smaller cervical cord area at the C2 level in MS compared to controls, and a decrease in cord area over 12 months, most marked in primary progressive MS (PPMS). A subset of subjects participating in a multicentre, double-blind, placebo-controlled clinical trial evaluating the efficacy of glatiramer acetate in PPMS (PROMiSe trial) were followed for 2 years. METHODS: 24 PPMS subjects, randomized to placebo (n = 9) and glatiramer acetate (n = 15), and 24 matched controls were studied. Cervical cord volume (CCV) at C2-3 was determined using a 3D inversion recovery (IR)-prepared spoiled-gradient echo sequence. Myelin water fraction (MWF) at C2-3 was obtained using a 32-echo IR-prepared relaxation sequence. Scans were repeated at baseline, years 1 and 2. RESULTS: Baseline CCV was significantly smaller for PPMS than controls [median (interquartile range) 951 (829-1043) vs. 1072 (1040-1129) mm(3), p = 0.0004] and MWF trended to be lower in PPMS cord [median (interquartile range) 0.225 (0.187-0.267) vs. 0.253 (0.235-0.266), p = 0.12]. Baseline CCV correlated with baseline Expanded Disability Status Scale, disease duration, brain white and grey matter volume. In PPMS, CCV was significantly decreased at year 1 (-0.83%, p = 0.04) and year 2 (-1.65%, p = 0.02). Baseline MWF correlated with baseline CCV and brain white and grey matter volume. MWF was significantly decreased from baseline for PPMS at year 2 (-10.5%, p = 0.01). Treatment effect was not detected on change in CCV nor MWF. CONCLUSIONS: Metrics at the level of the cord, including volume and MWF at C2-3, were lower in PPMS than controls and changed over 2 years only in PPMS.


Assuntos
Água Corporal , Esclerose Múltipla Crônica Progressiva/patologia , Bainha de Mielina/química , Medula Espinal/patologia , Adulto , Idoso , Atrofia/patologia , Encéfalo/patologia , Vértebras Cervicais , Progressão da Doença , Método Duplo-Cego , Feminino , Acetato de Glatiramer , Humanos , Imunossupressores/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Crônica Progressiva/tratamento farmacológico , Bainha de Mielina/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Peptídeos/uso terapêutico , Reprodutibilidade dos Testes , Medula Espinal/efeitos dos fármacos , Resultado do Tratamento
12.
Oncogene ; 29(14): 2013-23, 2010 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-20101236

RESUMO

Triple negative breast cancers (TNBCs) have a relatively poor prognosis and cannot be effectively treated with current targeted therapies. We searched for genes that have the potential to be therapeutic targets by identifying genes consistently overexpressed when amplified. Fifty-six TNBCs were subjected to high-resolution microarray-based comparative genomic hybridization (aCGH), of which 24 were subjected to genome-wide gene expression analysis. TNBCs were genetically heterogeneous; no individual focal amplification was present at high frequency, although 78.6% of TNBCs harboured at least one focal amplification. Integration of aCGH and expression data revealed 40 genes significantly overexpressed when amplified, including the known oncogenes and potential therapeutic targets, FGFR2 (10q26.3), BUB3 (10q26.3), RAB20 (13q34), PKN1 (19p13.12) and NOTCH3 (19p13.12). We identified two TNBC cell lines with FGFR2 amplification, which both had constitutive activation of FGFR2. Amplified cell lines were highly sensitive to FGFR inhibitor PD173074, and to RNAi silencing of FGFR2. Treatment with PD173074 induced apoptosis resulting partly from inhibition of PI3K-AKT signalling. Independent validation using publicly available aCGH data sets revealed FGFR2 gene was amplified in 4% (6/165) of TNBC, but not in other subtypes (0/214, P=0.0065). Our analysis demonstrates that TNBCs are heterogeneous tumours with amplifications of FGFR2 in a subgroup of tumours.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Animais , Apoptose , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Hibridização Genômica Comparativa , Dosagem de Genes/genética , Perfilação da Expressão Gênica , Genômica , Humanos , Ligantes , Fosfatidilinositol 3-Quinases/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Reprodutibilidade dos Testes , Transdução de Sinais
13.
Oncogene ; 28(46): 4075-94, 2009 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-19734938

RESUMO

Hsp90 chaperones stabilize many tyrosine kinases including several oncogenes, which are inhibited or induced to degrade by the Hsp90 inhibitor geldanamycin (GA). As a consequence, GA has been developed for future chemotherapeutic use in several tumour types including neuroblastoma (NB). Alternative splicing of the neurotrophin receptor tyrosine kinase TrkA may have a pivotal function in regulating NB behaviour, with reports suggesting that tumour-suppressing signals from TrkA may be converted to oncogenic signals by stress-regulated alternative TrkAIII splicing. Within this context, it is important to know whether Hsp90 interacts with TrkA variants in NB cells and how GA influences this. Here, we report that both TrkAI and TrkAIII are Hsp90 clients in human NB cells. TrkAI exhibits GA-sensitive interaction with Hsp90 required for receptor endoplasmic reticulum export, maturation, cell surface stabilization and ligand-mediated activation, whereas TrkAIII exhibits GA-sensitive interactions with Hsp90 required for spontaneous activity and to a lesser extent stability. We show that GA inhibits proliferation and induces apoptosis of TrkAI expressing NB cells, whereas TrkAIII reduces the sensitivity of NB cells to GA-induced elimination. Our data suggest that GA-sensitive interactions with Hsp90 are critical for both TrkAI tumour suppressor and TrkAIII oncogenic function in NB and that TrkAIII expression exerts a negative impact on GA-induced NB cell eradication, which can be counteracted by a novel TrkAIII-specific peptide nucleic acid inhibitor.


Assuntos
Benzoquinonas/farmacologia , Proteínas de Choque Térmico HSP90/metabolismo , Lactamas Macrocíclicas/farmacologia , Neuroblastoma/metabolismo , Receptor trkA/metabolismo , Processamento Alternativo , Antígenos de Superfície/metabolismo , Estabilidade Enzimática/efeitos dos fármacos , Genes Supressores de Tumor/efeitos dos fármacos , Genes Supressores de Tumor/fisiologia , Humanos , Isoenzimas/metabolismo , Isoenzimas/fisiologia , Neuroblastoma/genética , Neuroblastoma/patologia , Oncogenes/efeitos dos fármacos , Oncogenes/fisiologia , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Transporte Proteico/efeitos dos fármacos , Receptor trkA/antagonistas & inibidores , Receptor trkA/genética , Receptor trkA/fisiologia , Transfecção , Células Tumorais Cultivadas , Tirosina/metabolismo
14.
Br J Cancer ; 101(6): 973-82, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19707201

RESUMO

BACKGROUND: Malignant gliomas are the most prevalent type of primary brain tumours but the therapeutic armamentarium for these tumours is limited. Platelet-derived growth factor (PDGF) signalling has been shown to be a key regulator of glioma development. Clinical trials evaluating the efficacy of anti-PDGFRA therapies on gliomas are ongoing. In this study, we intended to analyse the expression of PDGFA and its receptor PDGFRA, as well as the underlying genetic (mutations and amplification) mechanisms driving their expression in a large series of human gliomas. METHODS: PDGFA and PDGFRA expression was evaluated by immunohistochemistry in a series of 160 gliomas of distinct World Health Organization (WHO) malignancy grade. PDGFRA-activating gene mutations (exons 12, 18 and 23) were assessed in a subset of 86 cases by PCR-single-strand conformational polymorphism (PCR-SSCP), followed by direct sequencing. PDGFRA gene amplification analysis was performed in 57 cases by quantitative real-time PCR (QPCR) and further validated in a subset of cases by chromogenic in situ hybridisation (CISH) and microarray-based comparative genomic hybridisation (aCGH). RESULTS: PDGFA and PDGFRA expression was found in 81.2% (130 out of 160) and 29.6% (48 out of 160) of gliomas, respectively. Its expression was significantly correlated with histological type of the tumours; however, no significant association between the expression of the ligand and its receptor was observed. The absence of PDGFA expression was significantly associated with the age of patients and with poor prognosis. Although PDGFRA gene-activating mutations were not found, PDGFRA gene amplification was observed in 21.1% (12 out of 57) of gliomas. No association was found between the presence of PDGFRA gene amplification and expression, excepting for grade II diffuse astrocytomas. CONCLUSION: The concurrent expression of PDGFA and PDGFRA in different subtypes of gliomas, reinforce the recognised significance of this signalling pathway in gliomas. PDGFRA gene amplification rather than gene mutation may be the underlying genetic mechanism driving PDGFRA overexpression in a portion of gliomas. Taken together, our results could provide in the future a molecular basis for PDGFRA-targeted therapies in gliomas.


Assuntos
Neoplasias Encefálicas/química , Dosagem de Genes , Glioma/química , Mutação , Fator de Crescimento Derivado de Plaquetas/análise , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/análise , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/genética , Criança , Pré-Escolar , Feminino , Amplificação de Genes , Glioma/genética , Humanos , Masculino , Pessoa de Meia-Idade , Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Transdução de Sinais
15.
J Clin Pathol ; 62(7): 604-12, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19561229

RESUMO

BACKGROUND: Secretory breast cancer (SBC) is a rare entity characterised by indolent clinical behaviour, distinctive histological features and the presence of a recurrent chromosomal translocation t(12;15)(p13;q25), leading to the formation of the ETV6-NTRK3 fusion gene. AIM: To describe the molecular genetic features of a case of SBC which harbours a duplication of the t(12;15) translocation. METHODS: Tiling path array comparative genomic hybridisation (aCGH) analysis and fluorescence in situ hybridisation (FISH) using in-house-generated probes for ETV6, NTRK3 and the fusion genes, centromeric probes for chromosomes 12 and 15, and a commercially available split-apart ETV6/NTRK3 probe. RESULTS: FISH revealed the presence of a duplication of the translocation t(12;15), which resulted from the gain of one copy of the derivative chromosome der(15)t(12;15), retention of one normal copy of both ETV6 and NTRK3 genes and deletion of the derivative chromosome der(12)t(12;15). Consistent with FISH findings, aCGH revealed copy number gains of ETV6 and NTRK3 and deletions encompassing the regions centromeric to ETV6 and telomeric to NTRK3. Additional regions of copy number changes included gains of 10q21, 10q26.3, 12p13.3-p13.31 15q11-q25.3 and 16pq and losses of 6q24.1-q27, 12p13.2-q12 and 15q25.3-q26.3. CONCLUSIONS: To the best of our knowledge, this is the first time a carcinoma has been shown to harbour a duplication of the ETV6-NTRK3 translocation. The presence of an additional copy of the derivative chromosome der(15)t(12;15) coupled with deletion of the other derivative der(12)t(12;15) in the modal population of cancer cells suggests that this was either an early phenomenon or conferred additional growth advantage on neoplastic cells.


Assuntos
Neoplasias da Mama/genética , Duplicação Gênica , Proteínas de Fusão Oncogênica/genética , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Cromossomos Humanos Par 12/genética , Cromossomos Humanos Par 15/genética , Feminino , Humanos , Hibridização in Situ Fluorescente/métodos , Translocação Genética
16.
J Pathol ; 216(4): 399-407, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18810758

RESUMO

Expression profiling studies have suggested that HER2-amplified breast cancers constitute a heterogeneous group that may be subdivided according to their ER status: HER2-amplified ER-positive breast carcinomas that fall into the luminal B cluster; and HER2-amplified ER-negative cancers which form a distinct molecular subgroup, known as the erbB2 or HER2 subgroup. ER-negative breast cancer differs significantly from ER-positive disease in the pattern, type, and complexity of genetic aberrations. Here we have compared the genomic profiles of ER-positive and ER-negative HER2-amplified cancers using tiling path microarray-based comparative genomic hybridization (aCGH). Validation of the differentially amplified regions was performed in an independent series of 70 HER2-amplified breast cancers. Although HER2-amplified cancers had remarkably complex patterns of molecular genetic aberrations, ER-positive and ER-negative HER2-amplified breast carcinomas shared most molecular genetic features as defined by aCGH. Genome-wide Fisher's exact test analysis revealed that less than 1.5% of the genome was significantly differentially gained or lost in ER-positive versus ER-negative HER2-amplified cancers. However, two regions of amplification were significantly associated with ER-positive carcinomas, one of which mapped to 17q21.2 and encompassed GJC1, IGFBP4, TNS4, and TOP2A. Chromogenic in situ hybridization analysis of an independent validation series confirmed the association between ER status and TOP2A amplification. In conclusion, although hormone receptor status does not determine the overall genetic profile of HER2-amplified breast cancers, specific genetic aberrations may be characteristic of subgroups of HER2 breast cancers.


Assuntos
Neoplasias da Mama/genética , Perfilação da Expressão Gênica , Genes erbB-2 , Análise de Sequência com Séries de Oligonucleotídeos , Receptores de Estrogênio/genética , Antígenos de Neoplasias/genética , Neoplasias da Mama/patologia , DNA Topoisomerases Tipo II/genética , Proteínas de Ligação a DNA/genética , Feminino , Amplificação de Genes , Humanos , Hibridização In Situ/métodos , Proteínas de Ligação a Poli-ADP-Ribose
17.
J Pathol ; 215(3): 231-44, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18473330

RESUMO

Pleomorphic lobular carcinomas (PLC) of the breast display histological features associated with classic invasive lobular carcinoma (ILC), yet they also exhibit more conspicuous nuclear atypia and pleomorphism, and an aggressive clinical behaviour. From a breast cancer progression perspective, it is unclear whether PLC is a variant of ILC or is a high-grade invasive ductal carcinoma (IDC) that has lost E-cadherin. The molecular features of 26 PLC were studied using immunohistochemistry [oestrogen receptor (ER), progesterone receptor (PR), HER2, p53 and E-cadherin], 0.9 Mb resolution, microarray-based comparative genomic hybridization (aCGH), fluorescent (FISH) and chromogenic (CISH) in situ hybridization and loss of heterozygosity. Comparative analysis was performed with aCGH data from PLC with classic ILC (16 cases) and high grade IDC (35 cases). PLCs were frequently ER- and PR-positive, E-cadherin-negative and occasionally HER2- and p53-positive. Recurrent copy number changes identified by aCGH included gains on 1q, 8q, 11q, 12q, 16p and 17q and losses on 8p, 11q, 13q, 16q and Xq. Highly recurrent 1q+ (100% of cases), 16p+ (93%), 11q- (53%) and 16q- (93%) and evidence of the der(1;16)/der(16)t(1;16) rearrangement, as detected by FISH, suggested that PLC had a 'lobular genotype'. Focal amplifications were evident at 8p12-p11, 8q24, 11q13.1-q14.1, 12q14, 17q12 and 20q13. Loss of BRCA2 was detected in 40% of PLC by LOH. Comparative analysis of aCGH data suggested the molecular features of PLC (ER/PR-positive, E-cadherin-negative, 1q+, 11q(-), 16p+ and 16q(-)) were more closely related to those of ILC than IDC, implicating an overlapping developmental pathway for these lobular tumour types. Molecular alterations found in PLC that are more typical of high-grade IDC than ILC (p53 and HER2 positivity, 8q+, 17q24-q25+, 13q(-) and amplification of 8q24, 12q14, 17q12 and 20q13) are likely to drive the high-grade and more aggressive biology of PLC.


Assuntos
Neoplasias da Mama/genética , Carcinoma Lobular/genética , Regulação Neoplásica da Expressão Gênica , Biomarcadores Tumorais/análise , Neoplasias da Mama/química , Carcinoma Ductal de Mama/química , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/química , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização In Situ , Perda de Heterozigosidade , Análise de Sequência com Séries de Oligonucleotídeos
18.
J Pathol ; 215(4): 398-410, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18484683

RESUMO

Pure invasive micropapillary carcinoma (MPC) is a special histological type that accounts for 0.7-3% of all breast cancers. MPC has a distinctive growth pattern and a more aggressive clinical behaviour than invasive ductal carcinomas of no special type (IDC-NSTs). To define the molecular characteristics of MPCs, we profiled a series of 12 MPCs and 24 grade and oestrogen receptor (ER)-matched IDC-NSTs using high-resolution microarray comparative genomic hybridization (aCGH). In addition, we generated a tissue microarray containing a series of 24 MPCs and performed immunohistochemical analysis with ER, PR, Ki-67, HER2, CK5/6, CK14, CK17, EGFR, topoisomerase-IIalpha, cyclin D1, caveolin-1, E-cadherin, and beta-catenin antibodies. In situ hybridization probes were employed to evaluate the prevalence of amplification of HER2, TOP2A, EGFR, CCND1, MYC, ESR1, and FGFR1 genes. aCGH analysis demonstrated that MPCs significantly differed from IDC-NSTs at the genomic level. Gains of 1q, 2q, 4p, 6p, 6q23.2-q27, 7p, 7q, 8p, 8q, 9p, 10p, 11q, 12p, 12q, 16p, 17p, 17q, 19p, 20p, 20q, and 21q, and losses of 1p, 2p, 6q11.1-q16.3, 6q21-q22.1, 9p, 11p, 15q, and 19q were more prevalent in MPCs. High-level gains/amplifications of 8p12-p11, 8q12, 8q13, 8q21, 8q23, 8q24, 17q21, 17q23, and 20q13 were significantly associated with MPCs. A comparison between 24 MPCs and a series of 48 grade and ER-matched IDC-NSTs revealed that high cyclin D1 expression, high proliferation rates, and MYC (8q24) amplification were significantly associated with MPCs. Our results demonstrate that MPCs have distinct histological features and molecular genetic profiles supporting the contention that they constitute a distinct pathological entity.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Perfilação da Expressão Gênica/métodos , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias da Mama/imunologia , Carcinoma Ductal de Mama/imunologia , Ciclina D1/genética , Progressão da Doença , Feminino , Amplificação de Genes , Marcadores Genéticos , Humanos , Imuno-Histoquímica , Imunofenotipagem , Hibridização in Situ Fluorescente , Oncogenes
19.
Br J Cancer ; 96(2): 341-51, 2007 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-17133270

RESUMO

We analysed the molecular genetic profiles of breast cancer samples before and after neoadjuvant chemotherapy with combination doxorubicin and cyclophosphamide (AC). DNA was obtained from microdissected frozen breast core biopsies from 44 patients before chemotherapy. Additional samples were obtained before the second course of chemotherapy (D21) and after the completion of the treatment (surgical specimens) in 17 and 21 patients, respectively. Microarray-based comparative genome hybridisation was performed using a platform containing approximately 5800 bacterial artificial chromosome clones (genome-wide resolution: 0.9 Mb). Analysis of the 44 pretreatment biopsies revealed that losses of 4p, 4q, 5q, 12q13.11-12q13.12, 17p11.2 and 17q11.2; and gains of 1p, 2p, 7q, 9p, 11q, 19p and 19q were significantly associated with oestrogen receptor negativity. 16q21-q22.1 losses were associated with lobular and 8q24 gains with ductal types. Losses of 5q33.3-q4 and 18p11.31 and gains of 6p25.1-p25.2 and Xp11.4 were associated with HER2 amplification. No correlations between DNA copy number changes and clinical response to AC were found. Microarray-based comparative genome hybridisation analysis of matched pretreatment and D21 biopsies failed to identify statistically significant differences, whereas a comparison between matched pretreatment and surgical samples revealed a statistically significant acquired copy number gain on 11p15.2-11p15.5. The modest chemotherapy-driven genomic changes, despite profound loss of cell numbers, suggest that there is little therapeutic selection of resistant non-modal cell lineages.


Assuntos
Neoplasias da Mama/genética , Quimioterapia Adjuvante , Hibridização de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos , Adulto , Neoplasias da Mama/patologia , Humanos , Hibridização in Situ Fluorescente , Fenótipo
20.
J Pathol ; 211(1): 52-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17103382

RESUMO

Despite aggressive salvage regimens, approximately half of all children who suffer a Wilms' tumour recurrence will die of their disease. Although there are increasing data on molecular genetic prognostic factors present in the tumour at diagnosis, there is little information regarding the molecular events that occur with Wilms' tumour progression and relapse. In the present study, microarray-based comparative genomic hybridization (aCGH) analysis has been carried out on 58 Wilms' tumour samples, which included 38 untreated primary and 20 recurrent tumours. A higher degree of copy number changes was observed in the recurrent tumours (33.0% genomic clones) than in the primary tumour (21.2%). Paired analysis highlighted the acquisition of 15q gain with high levels of IGF1R expression in the tumour recurrence in two cases. The most statistically significant abnormality acquired between diagnosis and relapse was loss of 17p. One case that experienced 17p loss was classified as favourable histology at diagnosis, but exhibited diffuse anaplasia at recurrence and had a homozygous TP53 deletion. Another instructive case with a constitutional 11p13 deletion presented with bilateral tumours and suffered two subsequent recurrences in the left kidney. A somatic WT1 mutation was found only in the right kidney tumour, while the constitutional 11p13 deletion was the only abnormality detected in the initial left kidney tumour by aCGH. The two subsequent relapses in the left kidney contained an accumulation of additional genetic alterations, including an independent WT1 mutation.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 11 , Perfilação da Expressão Gênica , Recidiva Local de Neoplasia/genética , Análise de Sequência com Séries de Oligonucleotídeos , Tumor de Wilms/genética , Aniridia/complicações , Aniridia/genética , Análise Mutacional de DNA , Progressão da Doença , Feminino , Deleção de Genes , Genes do Tumor de Wilms , Genes p53 , Homozigoto , Humanos , Interpretação de Imagem Assistida por Computador , Lactente , Masculino , Recidiva Local de Neoplasia/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tumor de Wilms/complicações , Tumor de Wilms/patologia
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