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1.
Clin Genet ; 101(3): 346-358, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34964109

RESUMO

Recessive mutations in the genes encoding the four subunits of the tRNA splicing endonuclease complex (TSEN54, TSEN34, TSEN15, and TSEN2) cause various forms of pontocerebellar hypoplasia, a disorder characterized by hypoplasia of the cerebellum and the pons, microcephaly, dysmorphisms, and other variable clinical features. Here, we report an intronic recessive founder variant in the gene TSEN2 that results in abnormal splicing of the mRNA of this gene, in six individuals from four consanguineous families affected with microcephaly, multiple craniofacial malformations, radiological abnormalities of the central nervous system, and cognitive retardation of variable severity. Remarkably, unlike patients with previously described mutations in the components of the TSEN complex, all the individuals that we report developed atypical hemolytic uremic syndrome (aHUS) with thrombotic microangiopathy, microangiopathic hemolytic anemia, thrombocytopenia, proteinuria, severe hypertension, and end-stage kidney disease (ESKD) early in life. Bulk RNA sequencing of peripheral blood cells of four affected individuals revealed abnormal tRNA transcripts, indicating an alteration of the tRNA biogenesis. Morpholino-mediated skipping of exon 10 of tsen2 in zebrafish produced phenotypes similar to human patients. Thus, we have identified a novel syndrome accompanied by aHUS suggesting the existence of a link between tRNA biology and vascular endothelium homeostasis, which we propose to name with the acronym TRACK syndrome (TSEN2 Related Atypical hemolytic uremic syndrome, Craniofacial malformations, Kidney failure).


Assuntos
Síndrome Hemolítico-Urêmica Atípica , Microcefalia , Animais , Síndrome Hemolítico-Urêmica Atípica/genética , Endonucleases/genética , Feminino , Humanos , Masculino , Microcefalia/complicações , Mutação/genética , RNA de Transferência , Peixe-Zebra/genética
2.
Mol Cancer Res ; 18(1): 46-56, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31619506

RESUMO

The AP-2γ transcription factor, encoded by the TFAP2C gene, regulates the expression of estrogen receptor-alpha (ERα) and other genes associated with hormone response in luminal breast cancer. Little is known about the role of AP-2γ in other breast cancer subtypes. A subset of HER2+ breast cancers with amplification of the TFAP2C gene locus becomes addicted to AP-2γ. Herein, we sought to define AP-2γ gene targets in HER2+ breast cancer and identify genes accounting for physiologic effects of growth and invasiveness regulated by AP-2γ. Comparing HER2+ cell lines that demonstrated differential response to growth and invasiveness with knockdown of TFAP2C, we identified a set of 68 differentially expressed target genes. CDH5 and CDKN1A were among the genes differentially regulated by AP-2γ and that contributed to growth and invasiveness. Pathway analysis implicated the MAPK13/p38δ and retinoic acid regulatory nodes, which were confirmed to display divergent responses in different HER2+ cancer lines. To confirm the clinical relevance of the genes identified, the AP-2γ gene signature was found to be highly predictive of outcome in patients with HER2+ breast cancer. We conclude that AP-2γ regulates a set of genes in HER2+ breast cancer that drive cancer growth and invasiveness. The AP-2γ gene signature predicts outcome of patients with HER2+ breast cancer and pathway analysis predicts that subsets of patients will respond to drugs that target the MAPK or retinoic acid pathways. IMPLICATIONS: A set of genes regulated by AP-2γ in HER2+ breast cancer that drive proliferation and invasion were identified and provided a gene signature that is predictive of outcome in HER2+ breast cancer.


Assuntos
Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Receptor ErbB-2/genética , Fator de Transcrição AP-2/genética , Neoplasias da Mama/enzimologia , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Feminino , Técnicas de Silenciamento de Genes , Humanos , Células MCF-7 , Receptor ErbB-2/biossíntese , Receptor ErbB-2/metabolismo , Transfecção , Resultado do Tratamento
3.
Dermatol Online J ; 23(8)2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29469740

RESUMO

Linear IgA bullous dermatosis is a rare autoimmune vesiculobullous disease characterized by linear deposition of IgA along the basement membrane zone. It is classically idiopathic, but may also arise secondary to drug exposure. A heterogeneous spectrum of clinical features has been described, including a rare, morbid variant mimicking toxic epidermal necrolysis. Herein, we present a case of vancomycin-induced linear IgA bullous dermatosis that manifested clinically as toxic epidermal necrolysis and resolved with dapsone therapy.


Assuntos
Antibacterianos/efeitos adversos , Dermatose Linear Bolhosa por IgA/diagnóstico , Dermatose Linear Bolhosa por IgA/tratamento farmacológico , Síndrome de Stevens-Johnson/diagnóstico , Vancomicina/efeitos adversos , Anti-Infecciosos/uso terapêutico , Dapsona/uso terapêutico , Diagnóstico Diferencial , Humanos , Dermatose Linear Bolhosa por IgA/induzido quimicamente , Dermatose Linear Bolhosa por IgA/patologia , Masculino , Pessoa de Meia-Idade
4.
Sci Rep ; 6: 32726, 2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27596933

RESUMO

Tumor angiogenesis is critical to tumor growth and metastasis, yet much is unknown about the role vascular cells play in the tumor microenvironment. In vitro models that mimic in vivo tumor neovascularization facilitate exploration of this role. Here we investigated lung adenocarcinoma cancer cells (344SQ) and endothelial and pericyte vascular cells encapsulated in cell-adhesive, proteolytically-degradable poly(ethylene) glycol-based hydrogels. 344SQ in hydrogels formed spheroids and secreted proangiogenic growth factors that significantly increased with exposure to transforming growth factor beta 1 (TGF-ß1), a potent tumor progression-promoting factor. Vascular cells in hydrogels formed tubule networks with localized activated TGF-ß1. To study cancer cell-vascular cell interactions, we engineered a 2-layer hydrogel with 344SQ and vascular cell layers. Large, invasive 344SQ clusters (area > 5,000 µm(2), circularity < 0.25) developed at the interface between the layers, and were not evident further from the interface or in control hydrogels without vascular cells. A modified model with spatially restricted 344SQ and vascular cell layers confirmed that observed cluster morphological changes required close proximity to vascular cells. Additionally, TGF-ß1 inhibition blocked endothelial cell-driven 344SQ migration. Our findings suggest vascular cells contribute to tumor progression and establish this culture system as a platform for studying tumor vascularization.


Assuntos
Células Sanguíneas/efeitos dos fármacos , Hidrogéis/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Polietilenoglicóis/química , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Células Sanguíneas/patologia , Comunicação Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Progressão da Doença , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/fisiopatologia , Neovascularização Patológica/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Microambiente Tumoral/efeitos dos fármacos
5.
Mol Genet Metab ; 117(1): 27-32, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26586473

RESUMO

UNLABELLED: Blood ammonia and glutamine levels are used as biomarkers of control in patients with urea cycle disorders (UCDs). This study was undertaken to evaluate glutamine variability and utility as a predictor of hyperammonemic crises (HACs) in UCD patients. METHODS: The relationships between glutamine and ammonia levels and the incidence and timing of HACs were evaluated in over 100 adult and pediatric UCD patients who participated in clinical trials of glycerol phenylbutyrate. RESULTS: The median (range) intra-subject 24-hour coefficient of variation for glutamine was 15% (8-29%) as compared with 56% (28%-154%) for ammonia, and the correlation coefficient between glutamine and concurrent ammonia levels varied from 0.17 to 0.29. Patients with baseline (fasting) glutamine values >900 µmol/L had higher baseline ammonia levels (mean [SD]: 39.6 [26.2]µmol/L) than patients with baseline glutamine ≤ 900 µmol/L (26.6 [18.0]µmol/L). Glutamine values >900 µmol/L during the study were associated with an approximately 2-fold higher HAC risk (odds ratio [OR]=1.98; p=0.173). However, glutamine lost predictive significance (OR=1.47; p=0.439) when concomitant ammonia was taken into account, whereas the predictive value of baseline ammonia ≥ 1.0 upper limit of normal (ULN) was highly statistically significant (OR=4.96; p=0.013). There was no significant effect of glutamine >900 µmol/L on time to first HAC crisis (hazard ratio [HR]=1.14; p=0.813), but there was a significant effect of baseline ammonia ≥ 1.0 ULN (HR=4.62; p=0.0011). CONCLUSIONS: The findings in this UCD population suggest that glutamine is a weaker predictor of HACs than ammonia and that the utility of the predictive value of glutamine will need to take into account concurrent ammonia levels.


Assuntos
Amônia/sangue , Glutamina/sangue , Hiperamonemia/sangue , Distúrbios Congênitos do Ciclo da Ureia/sangue , Adolescente , Adulto , Biomarcadores/sangue , Criança , Pré-Escolar , Jejum , Feminino , Glicerol/análogos & derivados , Glicerol/uso terapêutico , Humanos , Hiperamonemia/etiologia , Masculino , Fenilbutiratos/uso terapêutico , Valor Preditivo dos Testes , Distúrbios Congênitos do Ciclo da Ureia/tratamento farmacológico , Adulto Jovem
6.
Mol Cancer Res ; 14(3): 287-95, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26631572

RESUMO

UNLABELLED: Intratumoral collagen cross-links heighten stromal stiffness and stimulate tumor cell invasion, but it is unclear how collagen cross-linking is regulated in epithelial tumors. To address this question, we used Kras(LA1) mice, which develop lung adenocarcinomas from somatic activation of a Kras(G12D) allele. The lung tumors in Kras(LA1) mice were highly fibrotic and contained cancer-associated fibroblasts (CAF) that produced collagen and generated stiffness in collagen gels. In xenograft tumors generated by injection of wild-type mice with lung adenocarcinoma cells alone or in combination with CAFs, the total concentration of collagen cross-links was the same in tumors generated with or without CAFs, but coinjected tumors had higher hydroxylysine aldehyde-derived collagen cross-links (HLCC) and lower lysine-aldehyde-derived collagen cross-links (LCCs). Therefore, we postulated that an LCC-to-HLCC switch induced by CAFs promotes the migratory and invasive properties of lung adenocarcinoma cells. To test this hypothesis, we created coculture models in which CAFs are positioned interstitially or peripherally in tumor cell aggregates, mimicking distinct spatial orientations of CAFs in human lung cancer. In both contexts, CAFs enhanced the invasive properties of tumor cells in three-dimensional (3D) collagen gels. Tumor cell aggregates that attached to CAF networks on a Matrigel surface dissociated and migrated on the networks. Lysyl hydroxylase 2 (PLOD2/LH2), which drives HLCC formation, was expressed in CAFs, and LH2 depletion abrogated the ability of CAFs to promote tumor cell invasion and migration. IMPLICATIONS: CAFs induce a collagen cross-link switch in tumor stroma to influence the invasive properties of tumor cells.


Assuntos
Adenocarcinoma/patologia , Colágeno/metabolismo , Fibroblastos/patologia , Neoplasias Pulmonares/patologia , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/metabolismo , Células Tumorais Cultivadas/patologia , Adenocarcinoma/genética , Adenocarcinoma de Pulmão , Animais , Movimento Celular , Células Cultivadas , Técnicas de Cocultura , Fibroblastos/metabolismo , Neoplasias Pulmonares/genética , Camundongos , Neoplasias Experimentais , Proteínas Proto-Oncogênicas p21(ras)/genética
8.
Geobiology ; 13(1): 15-32, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25354129

RESUMO

Offshore facies of the Mesoproterozoic Sulky Formation, Dismal Lakes Group, arctic Canada, preserve microbialites with unusual morphology. These microbialites grew in water depths greater than several tens of meters and correlate with high-relief conical stromatolites of the more proximal September Lake reef complex. The gross morphology of these microbial facies consists of ridge-like vertical supports draped by concave-upward, subhorizontal elements, resulting in tent-shaped cuspate microbialites with substantial primary void space. Morphological and petrographic analyses suggest a model wherein penecontemporaneous upward growth of ridge elements and development of subhorizontal draping elements initially resulted in a buoyantly supported, unlithified microbial form. Lithification began via precipitation within organic elements during microbialite growth. Mineralization either stabilized or facilitated collapse of initially neutrally buoyant microbialite forms. Microbial structures and breccias were then further stabilized by precipitation of marine herringbone cement. During late-stage diagenesis, remaining void space was occluded by ferroan dolomite cement. Cuspate microbialites are most similar to those found in offshore facies of Neoarchean carbonate platforms and to unlithified, buoyantly supported microbial mats in modern ice-covered Antarctic lakes. We suggest that such unusual microbialite morphologies are a product of the interaction between motile and non-motile communities under nutrient-limiting conditions, followed by early lithification, which served to preserve the resultant microbial form. The presence of marine herringbone cement, commonly associated with high dissolved inorganic carbon (DIC), low O2 conditions, also suggests growth in association with reducing environments at or near the seafloor or in conjunction with a geochemical interface. Predominance of coniform stromatolite forms in the Proterozoic--across a variety of depositional environments--may thus reflect a combination of heterogeneous nutrient distribution, potentially driven by variable redox conditions, and an elevated carbonate saturation state, which permits preservation of these unusual microbialite forms.


Assuntos
Cianobactérias/crescimento & desenvolvimento , Sedimentos Geológicos/química , Sedimentos Geológicos/microbiologia , Fósseis , Nunavut
9.
Mol Genet Metab Rep ; 5: 12-14, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28649536

RESUMO

Urinary phenylacetylglutamine (U-PAGN) concentrations in spot urine samples were analyzed as a dosing biomarker during glycerol phenylbutyrate (GPB) dosing in 68 healthy adults and 66 adult and pediatric patients with urea cycle disorders who participated in GPB clinical trials. Age- and body surface area (BSA)-specific 25th percentile cutoff points for spot U-PAGN concentrations (<~9000 µg/mL for < 2 years old patients, < 7000 µg/mL for > 2 years with BSA ≤ 1.3 m2, and <~5000 µg/mL for > 2 years of age with BSA > 1.3 m2) were determined as an approach to identify patients for whom increased dosing and/or adherence to prescribed dosing should be assessed.

10.
Dermatol Online J ; 20(1): 21253, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24456956

RESUMO

A 50-year-old man presented with a several month history of a polypoid papule on the scrotum. A dense accumulation of macrophages with foamy cytoplasm was exhibited in the biopsy specimen leading to a diagnosis of verruciform xanthoma.


Assuntos
Escroto/patologia , Dermatopatias/diagnóstico , Xantomatose/diagnóstico , Biópsia , Diagnóstico Diferencial , Células Espumosas/ultraestrutura , Humanos , Ceratose/patologia , Masculino , Pessoa de Meia-Idade , Dermatopatias/patologia , Verrugas/diagnóstico , Xantomatose/patologia
11.
Arch Gynecol Obstet ; 289(4): 871-81, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24170160

RESUMO

PURPOSE: Epithelial-mesenchymal transition (EMT) endows cells with migratory and invasive properties, a prerequisite for the establishment of endometriotic lesions. However, the role EMT might play in the pathophysiology of endometriosis is still unknown. Therefore, we examined five recognized markers for EMT in endometrium and endometriosis: E-cadherin, N-cadherin, Twist, Snail and Slug. METHODS: Immunohistochemistry was used for peritoneal, ovarian and rectovaginal endometriotic lesions (n = 27) and endometrium (n = 13). Reverse transcription polymerase chain reaction was applied to tissue samples and primary cell cultures of endometriotic lesions (n = 9) and endometrium (n = 8). RESULTS: In endometriosis and endometrium E-cadherin, N-cadherin, Twist, Snail and Slug were expressed on protein and mRNA level. E-cadherin expression was strong in epithelial cells, but single E-cadherin-negative cells were frequently present in endometriosis. In endometriosis N-cadherin, Twist and Snail expression were upregulated in comparison with endometrium. The expression of E- and N-cadherin was inversely correlated, while that of N-cadherin and Twist was positively correlated. CONCLUSION: This study strongly suggests that EMT may be regulated differently in endometriosis and the endometrium. Future research should further elucidate the regulation of EMT in the endometrium and endometriosis.


Assuntos
Caderinas/metabolismo , Endometriose/metabolismo , Endométrio/metabolismo , Transição Epitelial-Mesenquimal/fisiologia , Fatores de Transcrição/metabolismo , Proteína 1 Relacionada a Twist/metabolismo , Adulto , Caderinas/genética , Núcleo Celular/metabolismo , Células Cultivadas , Citoplasma/metabolismo , Endometriose/patologia , Endometriose/cirurgia , Endométrio/patologia , Endométrio/cirurgia , Células Epiteliais/metabolismo , Feminino , Humanos , Imuno-Histoquímica , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genética , Proteína 1 Relacionada a Twist/genética
12.
J Biomech ; 47(9): 1969-78, 2014 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-24300038

RESUMO

Cancer progression is mediated by complex epigenetic, protein and structural influences. Critical among them are the biochemical, mechanical and architectural properties of the extracellular matrix (ECM). In recognition of the ECM's important role, cancer biologists have repurposed matrix mimetic culture systems first widely used by tissue engineers as new tools for in vitro study of tumor models. In this review we discuss the pathological changes in tumor ECM, the limitations of 2D culture on both traditional and polyacrylamide hydrogel surfaces in modeling these characteristics and advances in both naturally derived and synthetic scaffolds to facilitate more complex and controllable 3D cancer cell culture. Studies using naturally derived matrix materials like Matrigel and collagen have produced significant findings related to tumor morphogenesis and matrix invasion in a 3D environment and the mechanotransductive signaling that mediates key tumor-matrix interaction. However, lack of precise experimental control over important matrix factors in these matrices have increasingly led investigators to synthetic and semi-synthetic scaffolds that offer the engineering of specific ECM cues and the potential for more advanced experimental manipulations. Synthetic scaffolds composed of poly(ethylene glycol) (PEG), for example, facilitate highly biocompatible 3D culture, modular bioactive features like cell-mediated matrix degradation and complete independent control over matrix bioactivity and mechanics. Future work in PEG or similar reductionist synthetic matrix systems should enable the study of increasingly complex and dynamic tumor-ECM relationships in the hopes that accurate modeling of these relationships may reveal new cancer therapeutics targeting tumor progression and metastasis.


Assuntos
Matriz Extracelular/patologia , Neoplasias/patologia , Engenharia Tecidual , Animais , Humanos , Alicerces Teciduais , Microambiente Tumoral
13.
Mol Genet Metab ; 110(4): 446-53, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24144944

RESUMO

BACKGROUND: Phenylacetic acid (PAA) is the active moiety in sodium phenylbutyrate (NaPBA) and glycerol phenylbutyrate (GPB, HPN-100). Both are approved for treatment of urea cycle disorders (UCDs) - rare genetic disorders characterized by hyperammonemia. PAA is conjugated with glutamine in the liver to form phenylacetyleglutamine (PAGN), which is excreted in urine. PAA plasma levels ≥ 500 µg/dL have been reported to be associated with reversible neurological adverse events (AEs) in cancer patients receiving PAA intravenously. Therefore, we have investigated the relationship between PAA levels and neurological AEs in patients treated with these PAA pro-drugs as well as approaches to identifying patients most likely to experience high PAA levels. METHODS: The relationship between nervous system AEs, PAA levels and the ratio of plasma PAA to PAGN were examined in 4683 blood samples taken serially from: [1] healthy adults [2], UCD patients of ≥ 2 months of age, and [3] patients with cirrhosis and hepatic encephalopathy (HE). The plasma ratio of PAA to PAGN was analyzed with respect to its utility in identifying patients at risk of high PAA values. RESULTS: Only 0.2% (11) of 4683 samples exceeded 500 µg/ml. There was no relationship between neurological AEs and PAA levels in UCD or HE patients, but transient AEs including headache and nausea that correlated with PAA levels were observed in healthy adults. Irrespective of population, a curvilinear relationship was observed between PAA levels and the plasma PAA:PAGN ratio, and a ratio>2.5 (both in µg/mL) in a random blood draw identified patients at risk for PAA levels>500 µg/ml. CONCLUSIONS: The presence of a relationship between PAA levels and reversible AEs in healthy adults but not in UCD or HE patients may reflect intrinsic differences among the populations and/or metabolic adaptation with continued dosing. The plasma PAA:PAGN ratio is a functional measure of the rate of PAA metabolism and represents a useful dosing biomarker.


Assuntos
Glutamina/análogos & derivados , Encefalopatia Hepática/sangue , Fenilacetatos/sangue , Distúrbios Congênitos do Ciclo da Ureia/sangue , Biomarcadores/sangue , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/sangue , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Glutamina/administração & dosagem , Glutamina/sangue , Glicerol/administração & dosagem , Glicerol/análogos & derivados , Encefalopatia Hepática/etiologia , Encefalopatia Hepática/patologia , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Fenilacetatos/administração & dosagem , Fenilbutiratos/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Distúrbios Congênitos do Ciclo da Ureia/epidemiologia , Distúrbios Congênitos do Ciclo da Ureia/etiologia , Distúrbios Congênitos do Ciclo da Ureia/patologia
14.
PLoS One ; 8(6): e67054, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23785517

RESUMO

The extracellular matrix of epithelial tumors undergoes structural remodeling during periods of uncontrolled growth, creating regional heterogeneity and torsional stress. How matrix integrity is maintained in the face of dynamic biophysical forces is largely undefined. Here we investigated the role of fibulin-2, a matrix glycoprotein that functions biomechanically as an inter-molecular clasp and thereby facilitates supra-molecular assembly. Fibulin-2 was abundant in the extracellular matrix of human lung adenocarcinomas and was highly expressed in tumor cell lines derived from mice that develop metastatic lung adenocarcinoma from co-expression of mutant K-ras and p53. Loss-of-function experiments in tumor cells revealed that fibulin-2 was required for tumor cells to grow and metastasize in syngeneic mice, a surprising finding given that other intra-tumoral cell types are known to secrete fibulin-2. However, tumor cells grew and metastasized equally well in Fbln2-null and -wild-type littermates, implying that malignant progression was dependent specifically upon tumor cell-derived fibulin-2, which could not be offset by other cellular sources of fibulin-2. Fibulin-2 deficiency impaired the ability of tumor cells to migrate and invade in Boyden chambers, to create a stiff extracellular matrix in mice, to cross-link secreted collagen, and to adhere to collagen. We conclude that fibulin-2 is a driver of malignant progression in lung adenocarcinoma and plays an unexpected role in collagen cross-linking and tumor cell adherence to collagen.


Assuntos
Adenocarcinoma/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Neoplasias Pulmonares/metabolismo , Adenocarcinoma/genética , Adenocarcinoma de Pulmão , Animais , Western Blotting , Proteínas de Ligação ao Cálcio/genética , Adesão Celular/genética , Adesão Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/genética , Movimento Celular/fisiologia , Proteínas da Matriz Extracelular/genética , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/genética , Camundongos , Microscopia Eletrônica de Transmissão , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Cancer Res ; 72(22): 6013-23, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-22952217

RESUMO

Better understanding of the biophysical and biochemical cues of the tumor extracellular matrix environment that influence metastasis may have important implications for new cancer therapeutics. Initial exploration into this question has used naturally derived protein matrices that suffer from variability, poor control over matrix biochemistry, and inability to modify the matrix biochemistry and mechanics. Here, we report the use of a synthetic polymer-based scaffold composed primarily of poly(ethylene glycol), or PEG, modified with bioactive peptides to study murine models of lung adenocarcinoma. In this study, we focus on matrix-derived influences on epithelial morphogenesis of a metastatic cell line (344SQ) that harbors mutations in Kras and p53 (trp53) and is prone to a microRNA-200 (miR-200)-dependent epithelial-mesenchymal transition (EMT) and metastasis. The modified PEG hydrogels feature biospecific cell adhesion and cell-mediated proteolytic degradation with independently adjustable matrix stiffness. 344SQ encapsulated in bioactive peptide-modified, matrix metalloproteinase-degradable PEG hydrogels formed lumenized epithelial spheres comparable to that seen with three-dimensional culture in Matrigel. Altering both matrix stiffness and the concentration of cell-adhesive ligand significantly influenced epithelial morphogenesis as manifest by differences in the extent of lumenization, in patterns of intrasphere apoptosis and proliferation, and in expression of epithelial polarity markers. Regardless of matrix composition, exposure to TGF-ß induced a loss of epithelial morphologic features, shift in expression of EMT marker genes, and decrease in mir-200 levels consistent with EMT. Our findings help illuminate matrix-derived cues that influence epithelial morphogenesis and highlight the potential utility that this synthetic matrix-mimetic tool has for cancer biology.


Assuntos
Adenocarcinoma/patologia , Técnicas de Cultura de Células/métodos , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal , Hidrogéis/química , Neoplasias Pulmonares/patologia , Adenocarcinoma/genética , Adenocarcinoma de Pulmão , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Matriz Extracelular/genética , Matriz Extracelular/patologia , Genes p53 , Genes ras , Neoplasias Pulmonares/genética , Camundongos , Mutação , Oligopeptídeos/química , Polietilenoglicóis/química
16.
Mol Genet Metab ; 107(3): 308-14, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22958974

RESUMO

UNLABELLED: We have analyzed pharmacokinetic data for glycerol phenylbutyrate (also GT4P or HPN-100) and sodium phenylbutyrate with respect to possible dosing biomarkers in patients with urea cycle disorders (UCD). STUDY DESIGN: These analyses are based on over 3000 urine and plasma data points from 54 adult and 11 pediatric UCD patients (ages 6-17) who participated in three clinical studies comparing ammonia control and pharmacokinetics during steady state treatment with glycerol phenylbutyrate or sodium phenylbutyrate. All patients received phenylbutyric acid equivalent doses of glycerol phenylbutyrate or sodium phenylbutyrate in a cross over fashion and underwent 24-hour blood samples and urine sampling for phenylbutyric acid, phenylacetic acid and phenylacetylglutamine. RESULTS: Patients received phenylbutyric acid equivalent doses of glycerol phenylbutyrate ranging from 1.5 to 31.8 g/day and of sodium phenylbutyrate ranging from 1.3 to 31.7 g/day. Plasma metabolite levels varied widely, with average fluctuation indices ranging from 1979% to 5690% for phenylbutyric acid, 843% to 3931% for phenylacetic acid, and 881% to 1434% for phenylacetylglutamine. Mean percent recovery of phenylbutyric acid as urinary phenylacetylglutamine was 66.4 and 69.0 for pediatric patients and 68.7 and 71.4 for adult patients on glycerol phenylbutyrate and sodium phenylbutyrate, respectively. The correlation with dose was strongest for urinary phenylacetylglutamine excretion, either as morning spot urine (r = 0.730, p < 0.001) or as total 24-hour excretion (r = 0.791 p<0.001), followed by plasma phenylacetylglutamine AUC(24-hour), plasma phenylacetic acid AUC(24-hour) and phenylbutyric acid AUC(24-hour). Plasma phenylacetic acid levels in adult and pediatric patients did not show a consistent relationship with either urinary phenylacetylglutamine or ammonia control. CONCLUSION: The findings are collectively consistent with substantial yet variable pre-systemic (1st pass) conversion of phenylbutyric acid to phenylacetic acid and/or phenylacetylglutamine. The variability of blood metabolite levels during the day, their weaker correlation with dose, the need for multiple blood samples to capture trough and peak, and the inconsistency between phenylacetic acid and urinary phenylacetylglutamine as a marker of waste nitrogen scavenging limit the utility of plasma levels for therapeutic monitoring. By contrast, 24-hour urinary phenylacetylglutamine and morning spot urine phenylacetylglutamine correlate strongly with dose and appear to be clinically useful non-invasive biomarkers for compliance and therapeutic monitoring.


Assuntos
Amônia/urina , Glutamina/análogos & derivados , Glicerol/análogos & derivados , Fenilacetatos/urina , Fenilbutiratos/urina , Distúrbios Congênitos do Ciclo da Ureia/tratamento farmacológico , Distúrbios Congênitos do Ciclo da Ureia/urina , Adolescente , Adulto , Amônia/sangue , Biomarcadores Farmacológicos/sangue , Biomarcadores Farmacológicos/urina , Criança , Estudos Cross-Over , Esquema de Medicação , Feminino , Glutamina/sangue , Glutamina/urina , Glicerol/sangue , Glicerol/farmacocinética , Glicerol/urina , Humanos , Masculino , Fenilacetatos/sangue , Fenilbutiratos/sangue , Fenilbutiratos/farmacocinética , Distúrbios Congênitos do Ciclo da Ureia/sangue
17.
Magn Reson Imaging ; 30(9): 1249-56, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22770688

RESUMO

INTRODUCTION: The National Cancer Institute Quantitative Research Network (QIN) is a collaborative research network whose goal is to share data, algorithms and research tools to accelerate quantitative imaging research. A challenge is the variability in tools and analysis platforms used in quantitative imaging. Our goal was to understand the extent of this variation and to develop an approach to enable sharing data and to promote reuse of quantitative imaging data in the community. METHODS: We performed a survey of the current tools in use by the QIN member sites for representation and storage of their QIN research data including images, image meta-data and clinical data. We identified existing systems and standards for data sharing and their gaps for the QIN use case. We then proposed a system architecture to enable data sharing and collaborative experimentation within the QIN. RESULTS: There are a variety of tools currently used by each QIN institution. We developed a general information system architecture to support the QIN goals. We also describe the remaining architecture gaps we are developing to enable members to share research images and image meta-data across the network. CONCLUSIONS: As a research network, the QIN will stimulate quantitative imaging research by pooling data, algorithms and research tools. However, there are gaps in current functional requirements that will need to be met by future informatics development. Special attention must be given to the technical requirements needed to translate these methods into the clinical research workflow to enable validation and qualification of these novel imaging biomarkers.


Assuntos
Diagnóstico por Imagem/métodos , Informática Médica/métodos , Algoritmos , Pesquisa Biomédica/métodos , Bases de Dados Factuais , Humanos , Disseminação de Informação/métodos , Neoplasias/diagnóstico , Neoplasias/patologia , Desenvolvimento de Programas , Software , Estados Unidos
18.
Geburtshilfe Frauenheilkd ; 72(11): 1004-1008, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25258456

RESUMO

Background: There are no current studies on the opinions of obstetricians and gynaecologists in Germany about emergency contraception (or post-coital contraception, morning-after pill). The opinions of a large group of physicians were collected using of a questionnaire and compared with the results of an American survey (n = 1154). Methods: A two-part questionnaire was used - part 1: sociodemographic data, part 2: 4 scenarios to illustrate the possible advantages and disadvantages of free access to emergency contraception as well as 4 indications and situations for which emergency contraception can be prescribed. Results: The response rate was 91.7 % (165/180 questionnaires). 63.9 % (103/161) of the German responding physicians were of the opinion that women with access to emergency contraception experienced unwanted pregnancies less frequently than those without access. Merely 26.2 % of the responding physicians supported the prescription-free availability of emergency contraception in apothecaries. The German-American comparison ultimately revealed only a few major differences, e.g., in answers to the question whether or not access to emergency contraception could reduce the number of unwanted pregnancies (89 vs. 64 %). Conclusions: The high rejection rate of free access to emergency contraception of almost 70 % in our surveyed group supports the current position published by the German Society for Gynaecology and Obstetrics (Deutsche Gesellschaft für Gynäkologie und Geburtshilfe) and the German Professional Union of Gynaecologists (deutscher Berufsverband der Frauenärzte). Since other medical organisations, e.g., WHO, supported the prescription-free access to levonorgestrel formulations as emergency contraception a few years ago, it would be interesting to ask a larger sample of German gynaecologists and obstetricians about their opinions on emergency contraception.

19.
J Laryngol Otol ; 124(5): 465-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20067648

RESUMO

INTRODUCTION: At the turn of the twentieth century, ultraviolet light was successfully used to treat tuberculosis of the skin. Upper respiratory tract infections had been inversely associated with sun exposure. During the last decade, basic scientific research demonstrated that vitamin D has an important anti-infective role. METHOD: Review of the relevant literature on the influence of vitamin D on innate immunity and respiratory tract infection. RESULTS: Vitamin D is involved in the production of defensins and cathelicidin - antimicrobial peptides that provide a natural defence against potential microbiological pathogens. Vitamin D supplementation increases cathelicidin production. Low vitamin D levels are associated with an increased incidence of upper respiratory tract infections. CONCLUSIONS: Vitamin D appears to play an important role in the regulation of innate immunity in the upper respiratory tract. Optimal vitamin D levels and appropriate dosing schedules have yet to be determined.


Assuntos
Infecções Respiratórias/prevenção & controle , Vitamina D/farmacologia , Vitaminas/farmacologia , Peptídeos Catiônicos Antimicrobianos/fisiologia , Helioterapia , Humanos , Imunidade Inata/efeitos dos fármacos , Imunidade nas Mucosas/efeitos dos fármacos , Infecções Respiratórias/imunologia , Tuberculose Cutânea/terapia , Vitamina D/sangue , Vitamina D/fisiologia , Vitaminas/sangue
20.
J Laryngol Otol ; 124(5): 495-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20053307

RESUMO

BACKGROUND: Bacterial biofilms have been implicated in the pathogenesis of chronic rhinosinusitis. In the laboratory setting, ultrasound is effective in disrupting such biofilms; however, few clinical studies have evaluated the role of therapeutic ultrasound in chronic rhinosinusitis. OBJECTIVE: This study was performed to investigate the short-term effectiveness of therapeutic ultrasound as a treatment modality for chronic rhinosinusitis. METHODS: Twenty-two patients with a positive history of chronic rhinosinusitis, according to the criteria set out by the Rhinosinusitis Task Force, together with a previous computed tomography scan compatible with a diagnosis of chronic rhinosinusitis, and who had failed previous, aggressive medical management, were treated with therapeutic pulsed ultrasound at 1 MHz two to three days per week for six sessions. Patients completed an assessment of individual sinus symptom severity and the 20-Item Sino-Nasal Outcome Test questionnaire before treatment, prior to session four and after completion of session six. RESULTS: Two patients were unable to complete the study protocol. After completion of session six, 18 patients had experienced improvement in symptoms, while two patients noted a worsening of symptoms. Median percentage improvement of the total overall symptom score was 16.7 per cent (Wilcoxon signed rank, p < 0.001). The 20-Item Sino-Nasal Outcome Test score improved by 34.1 per cent (Wilcoxon signed rank, p < 0.0001). CONCLUSION: This study demonstrated a significant improvement in chronic rhinosinusitis symptoms after a six-session course of pulsed ultrasound therapy. Treatment with ultrasound alone or combined with antibiotics may provide a strategy to target biofilms on the sinus mucosa. Therapeutic ultrasound warrants further investigation as a potential treatment modality for chronic rhinosinusitis.


Assuntos
Rinite/terapia , Sinusite/terapia , Terapia por Ultrassom/métodos , Adolescente , Adulto , Idoso , Antibacterianos/uso terapêutico , Biofilmes , Doença Crônica , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rinite/diagnóstico por imagem , Índice de Gravidade de Doença , Sinusite/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
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