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1.
J Cytol ; 38(1): 21-30, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33935388

RESUMO

CONTEXT: Radiology and pathology are pivotal tools in the investigational artillery for management of wide spectrum of hepatic lesions and early detection is of a paramount importance. AIMS: The study aimed at analyzing the efficacy, comparative yield and validity of image-guided aspiration cytology (FNA)/core biopsy (CB) in focal hepatic lesions. SETTINGS AND DESIGN: A retrospective hospital-based study was conducted in departments of Pathology and Radiology and Imaging of a tertiary care center. MATERIALS AND METHODS: Cases of focal hepatic lesions that underwent percutaneous image guided-FNA reported (2011-2018) were analyzed. Cytological-histopathological correlation was performed where available. FNA diagnoses were divided into four categories-positive for malignancy (group 1), atypical (group 2), negative for malignancy (group 3), and non-diagnostic (group 4). STATISTICAL ANALYSIS USED: Categorical data was depicted in the form of frequencies and proportions. Validity of percutaneous image-guided FNA diagnosis was collated with the final diagnosis and results were analyzed. RESULTS: A total of 338 FNA of focal hepatic lesions were reported in which 217 (68.2%) cases in group 1; 21 (6.2%) in group 2; 58 (17.2%) in group 3 and 42 (12.4%) in group 4. CB correlation was available in 123 cases. Based on clinical, radiological and pathological findings, conclusive final diagnoses were obtained and the cases were regrouped [malignant cases-245, benign lesions-57 and uncertain lesions-36]. Metastasis was the most common malignancy (175/245; 71.4%). Sensitivity, specificity, and overall diagnostic accuracy of FNA to categorize the lesion as benign or malignant were 96.94%, 100% and 97.51%, respectively. However, the cytology-histopathology correlation revealed discordance of subtyping the lesion in 20% of cases and sensitivity and specificity reduced to 80% and 50% respectively in rendering the specific diagnosis. CONCLUSIONS: Percutaneous image-guided FNA is a sensitive and specific tool with high diagnostic accuracy in evaluating focal hepatic lesions. The study highlights the pre-eminence of interventional radiology and cytology in the care of patients with liver lesions.

2.
Elife ; 82019 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-31799933

RESUMO

Appropriate regulation of autophagy is crucial for clearing toxic proteins from cells. Defective autophagy results in accumulation of toxic protein aggregates that detrimentally affect cellular function and organismal survival. Here, we report that the microRNA miR-1 regulates the autophagy pathway through conserved targeting of the orthologous Tre-2/Bub2/CDC16 (TBC) Rab GTPase-activating proteins TBC-7 and TBC1D15 in Caenorhabditis elegans and mammalian cells, respectively. Loss of miR-1 causes TBC-7/TBC1D15 overexpression, leading to a block on autophagy. Further, we found that the cytokine interferon-ß (IFN-ß) can induce miR-1 expression in mammalian cells, reducing TBC1D15 levels, and safeguarding against proteotoxic challenges. Therefore, this work provides a potential therapeutic strategy for protein aggregation disorders.


Assuntos
Autofagia , Caenorhabditis elegans/metabolismo , Interferon beta/metabolismo , MicroRNAs/metabolismo , Agregados Proteicos , Regiões 3' não Traduzidas/genética , Animais , Sequência de Bases , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Células HeLa , Humanos , Proteína Huntingtina/metabolismo , Camundongos , Proteínas Mutantes/metabolismo , Peptídeos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , proteínas de unión al GTP Rab7
3.
Nat Commun ; 8: 14105, 2017 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-28102238

RESUMO

Functional interplay between tumour cells and their neoplastic extracellular matrix plays a decisive role in malignant progression of carcinomas. Here we provide a comprehensive data set of the human HNSCC-associated fibroblast matrisome. Although much attention has been paid to the deposit of collagen, we identify oncofetal fibronectin (FN) as a major and obligate component of the matrix assembled by stromal fibroblasts from head and neck squamous cell carcinomas (HNSCC). FN overexpression in tumours from 435 patients corresponds to an independent unfavourable prognostic indicator. We show that migration of carcinoma collectives on fibrillar FN-rich matrices is achieved through αvß6 and α9ß1 engagement, rather than α5ß1. Moreover, αvß6-driven migration occurs independently of latent TGF-ß activation and Smad-dependent signalling in tumour epithelial cells. These results provide insights into the adhesion-dependent events at the tumour-stroma interface that govern the collective mode of migration adopted by carcinoma cells to invade surrounding stroma in HNSCC.


Assuntos
Carcinoma de Células Escamosas , Movimento Celular/efeitos dos fármacos , Fibronectinas/metabolismo , Neoplasias de Cabeça e Pescoço , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Matriz Extracelular , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Integrinas/genética , Integrinas/metabolismo , Masculino , Pessoa de Meia-Idade , Carcinoma de Células Escamosas de Cabeça e Pescoço
4.
Matrix Biol ; 60-61: 57-69, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27751945

RESUMO

Cell-extracellular matrix (ECM) and cell-cell junctions that employ microfilaments are sites of tension. They are important for tissue repair, morphogenetic movements and can be emblematic of matrix contraction in fibrotic disease and the stroma of solid tumors. One cell surface receptor, syndecan-4, has been shown to regulate focal adhesions, junctions that form at the ends of microfilament bundles in response to matrix components such as fibronectin. Recently it has been shown that signaling emanating from this proteoglycan receptor includes regulation of Rho family GTPases and cytosolic calcium. While it is known that cell-ECM and cell-cell junctions may be linked, possible roles for syndecans in this process are not understood. Here we show that wild type primary fibroblasts and those lacking syndecan-4 utilize different cadherins in their adherens junctions and that tension is a major factor in this differential response. This corresponds to the reduced ability of fibroblasts lacking syndecan-4 to exert tension on the ECM and we now show that this may extend to reduced tension in cell-cell adhesion.


Assuntos
Junções Aderentes/metabolismo , Caderinas/genética , Cateninas/metabolismo , Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Sindecana-4/genética , Junções Aderentes/genética , Junções Aderentes/ultraestrutura , Animais , Fenômenos Biomecânicos , Caderinas/metabolismo , Cateninas/genética , Adesão Celular , Matriz Extracelular/genética , Matriz Extracelular/ultraestrutura , Fibroblastos/ultraestrutura , Quinase 1 de Adesão Focal/genética , Quinase 1 de Adesão Focal/metabolismo , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Camundongos , Nectinas/genética , Nectinas/metabolismo , Paxilina/genética , Paxilina/metabolismo , Cultura Primária de Células , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Transdução de Sinais , Sindecana-4/deficiência , Vinculina/genética , Vinculina/metabolismo , delta Catenina
5.
Biochim Biophys Acta ; 1855(2): 276-300, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25829250

RESUMO

Proteoglycans control numerous normal and pathological processes, among which are morphogenesis, tissue repair, inflammation, vascularization and cancer metastasis. During tumor development and growth, proteoglycan expression is markedly modified in the tumor microenvironment. Altered expression of proteoglycans on tumor and stromal cell membranes affects cancer cell signaling, growth and survival, cell adhesion, migration and angiogenesis. Despite the high complexity and heterogeneity of breast cancer, the rapid evolution in our knowledge that proteoglycans are among the key players in the breast tumor microenvironment suggests their potential as pharmacological targets in this type of cancer. It has been recently suggested that pharmacological treatment may target proteoglycan metabolism, their utilization as targets for immunotherapy or their direct use as therapeutic agents. The diversity inherent in the proteoglycans that will be presented herein provides the potential for multiple layers of regulation of breast tumor behavior. This review summarizes recent developments concerning the biology of selected proteoglycans in breast cancer, and presents potential targeted therapeutic approaches based on their novel key roles in breast cancer.


Assuntos
Neoplasias da Mama/genética , Neovascularização Patológica/genética , Proteoglicanas/biossíntese , Pesquisa Translacional Biomédica , Neoplasias da Mama/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Terapia de Alvo Molecular , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Proteoglicanas/antagonistas & inibidores , Proteoglicanas/uso terapêutico , Transdução de Sinais/genética , Microambiente Tumoral/genética
6.
BMC Cancer ; 15: 137, 2015 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-25885109

RESUMO

BACKGROUND: The use of imaging to implement on-treatment adaptation of radiotherapy is a promising paradigm but current data on imaging changes during radiotherapy is limited. This is a hypothesis-generating pilot study to examine the changes on multi-modality anatomic and functional imaging during (chemo)radiotherapy treatment for head and neck squamous cell carcinoma (HNSCC). METHODS: Eight patients with locally advanced HNSCC underwent imaging including computed tomography (CT), Fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET)-CT and magnetic resonance imaging (MRI) (including diffusion weighted (DW) and dynamic contrast enhanced (DCE)) at baseline and during (chemo)radiotherapy treatment (after fractions 11 and 21). Regions of interest (ROI) were drawn around the primary tumour at baseline and during treatment. Imaging parameters included gross tumour volume (GTV) assessment, SUVmax, mean ADC value and DCE-MRI parameters including Plasma Flow (PF). On treatment changes and correlations between these parameters were analysed using a Wilcoxon rank sum test and Pearson's linear correlation coefficient respectively. A p-value <0.05 was considered statistically significant. RESULTS: Statistically significant reductions in GTV-CT, GTV-MRI and GTV-DW were observed between all imaging timepoints during radiotherapy. Changes in GTV-PET during radiotherapy were heterogeneous and non-significant. Significant changes in SUVmax, mean ADC value, Plasma Flow and Plasma Volume were observed between the baseline and the fraction 11 timepoint, whilst only changes in SUVmax between baseline and the fraction 21 timepoint were statistically significant. Significant correlations were observed between multiple imaging parameters, both anatomical and functional; 20 correlations between baseline to the fraction 11 timepoint; 12 correlations between baseline and the fraction 21 timepoints; and 4 correlations between the fraction 11 and fraction 21 timepoints. CONCLUSIONS: Multi-modality imaging during radiotherapy treatment demonstrates early changes (by fraction 11) in both anatomic and functional imaging parameters. All functional imaging modalities are potentially complementary and should be considered in combination to provide multi-parametric tumour assessment, to guide potential treatment adaptation strategies. TRIAL REGISTRATION: ISRCTN Registry: ISRCTN34165059 . Registered 2nd February 2015.


Assuntos
Fluordesoxiglucose F18 , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Feminino , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Projetos Piloto , Tomografia por Emissão de Pósitrons/métodos , Estudos Prospectivos , Tomografia Computadorizada por Raios X/métodos
7.
Int J Exp Pathol ; 96(1): 1-10, 2015 02.
Artigo em Inglês | MEDLINE | ID: mdl-25546317

RESUMO

In the 25 years, as the first of the syndecan family was cloned, interest in these transmembrane proteoglycans has steadily increased. While four distinct members are present in mammals, one is present in invertebrates, including C. elegans that is such a powerful genetic model. The syndecans, therefore, have a long evolutionary history, indicative of important roles. However, these roles have been elusive. The knockout in the worm has a developmental neuronal phenotype, while knockouts of the syndecans in the mouse are mild and mostly limited to post-natal rather than developmental effects. Moreover, their association with high-affinity receptors, such as integrins, growth factor receptors, frizzled and slit/robo, have led to the notion that syndecans are coreceptors, with minor roles. Given that their heparan sulphate chains can gather many different protein ligands, this gave credence to views that the importance of syndecans lay with their ability to concentrate ligands and that only the extracellular polysaccharide was of significance. Syndecans are increasingly identified with roles in the pathogenesis of many diseases, including tumour progression, vascular disease, arthritis and inflammation. This has provided impetus to understanding syndecan roles in more detail. It emerges that while the cytoplasmic domains of syndecans are small, they have clear interactive capabilities, most notably with the actin cytoskeleton. Moreover, through the binding and activation of signalling molecules, it is likely that syndecans are important receptors in their own right. Here, an overview of syndecan structure and function is provided, with some prospects for the future.


Assuntos
Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Sindecanas/metabolismo , Animais , Genótipo , Humanos , Inflamação/metabolismo , Ligantes , Camundongos Knockout , Neoplasias/metabolismo , Fenótipo , Conformação Proteica , Receptores de Superfície Celular/química , Receptores de Superfície Celular/deficiência , Receptores de Superfície Celular/genética , Relação Estrutura-Atividade , Sindecanas/química , Sindecanas/deficiência , Sindecanas/genética
8.
J Cytol ; 30(3): 162-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24130407

RESUMO

BACKGROUND: Endoscopic evaluation is critical in assessing the cause of obstructive jaundice. Cytological techniques including bile aspiration and biliary brushings have become the initial diagnostic modality. AIM: The aim of this study is to evaluate the role of endoscopic biliary tract cytology as a diagnostic tool in the evaluation of extrahepatic cholestatic jaundice. MATERIALS AND METHODS: A total of 56 biliary tract specimens including 34 bile aspirations and 22 biliary brushings from 41 consecutive patients who had presented with obstructive jaundice and underwent endoscopic retrograde cholangiopancreatography (ERCP) were assessed by cytological examination. The smears prepared were analyzed for standard cytological features. RESULTS: Cytologic diagnosis was adenocarcinoma in 13 (31.7%) cases, atypical in 2 (4.9%), reactive in 3 (7.3%) and benign changes in 19 (46.3%) cases. 4 (9.8%) cases were non-diagnostic. Serum bilirubin was significantly elevated in the malignant group. Biliary stricture was the most common finding on ERCP (68.3%). On cytological examination, presence of solitary, intact atypical cells, enlarged nuclei, irregular nuclear membrane, coarse chromatin and nucleoli were important cytologic criteria for differentiating malignant from benign biliary specimens. CONCLUSIONS: Regular use of bile cytology and brushings during ERCP evaluation of extrahepatic cholestatic jaundice is invaluable in obtaining a morphologic diagnosis. A systematic approach, use of strict cytomorphologic criteria and inclusion of significant atypia as malignant diagnosis may improve the sensitivity.

9.
Cell Tissue Res ; 339(1): 31-46, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19597846

RESUMO

Syndecans are type I transmembrane proteins having a core protein modified with glycosaminoglycan chains, most commonly heparan sulphate. They are an ancient group of molecules, present in invertebrates and vertebrates. Among the plethora of molecules that can interact with heparan sulphate, the collagens and glycoproteins of the extracellular matrix are prominent. Frequently, they do so in conjunction with other receptors, most notably the integrins. For this reason, they are often referred to as "co-receptors". However, just as with integrins, syndecans can interact with actin-associated proteins and signalling molecules, such as protein kinases. Some aspects of syndecan signalling are understood but much remains to be learned. The functions of syndecans in regulating cell adhesion and extracellular matrix assembly are described here. Evidence from null mice suggests that syndecans have roles in postnatal tissue repair, inflammation and tumour progression. Developmental deficits in lower vertebrates in which syndecans are eliminated are also informative and suggest that, in mammals, redundancy is a key issue.


Assuntos
Colágeno/metabolismo , Matriz Extracelular/metabolismo , Heparitina Sulfato/metabolismo , Transdução de Sinais , Sindecanas/metabolismo , Animais , Colágeno/genética , Matriz Extracelular/genética , Heparitina Sulfato/genética , Humanos , Integrinas/genética , Integrinas/metabolismo , Camundongos , Camundongos Mutantes , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Sindecanas/genética
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