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1.
Cureus ; 15(12): e51050, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38146336

RESUMO

This case report discusses a 64-year-old male who presented with a perineal abscess following the insertion of the SpaceOAR hydrogel, highlighting a rare but potentially serious complication of the hydrogel. Hydrogel spacers have become integral in prostate cancer radiotherapy by reducing rectal toxicity. Ensuring proper technique, prophylactic antibiotics, and vigilant post-insertion monitoring are crucial for averting complications. This case underscores the significance of early diagnosis and management in preventing severe consequences and emphasizes the need for a high index of clinical suspicion when patients present with post-insertion symptoms.

2.
Ann Surg ; 276(5): e275-e283, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35801709

RESUMO

OBJECTIVE: The objective of this study was to assess the quality and accuracy of visual abstracts published in academic surgical journals. BACKGROUND: Visual abstracts are commonly used to disseminate medical research findings. They distill the key messages of a research article, presenting them graphically in an engaging manner so that potential readers can decide whether to read the complete manuscript. METHODS: We developed the Visual Abstract Assessment Tool based upon published guidelines. Seven reviewers underwent iterative training to apply the tool. We collected visual abstracts published by 25 surgical journals from January 2017 to April 2021; those corresponding to systematic reviews without meta-analysis, conference abstracts, narrative reviews, video abstracts, or nonclinical research were excluded. Included visual abstracts were scored on accuracy (as compared with written abstracts) and design, and were given a "first impression" score. RESULTS: Across 25 surgical journals 1325 visual abstracts were scored. We found accuracy deficits in the reporting of study design (35.8%), appropriate icon use (49%), and sample size reporting (69.2%), and design deficits in element alignment (54.8%) and symmetry (36.1%). Overall scores ranged from 9 to 14 (out of 15), accuracy scores from 4 to 8 (out of 8), and design scores from 3 to 7 (out of 7). No predictors of visual abstract score were identified. CONCLUSION: Visual abstracts vary widely in quality. As visual abstracts become integrated with the traditional components of scientific publication, they must be held to similarly high standards. We propose a checklist to be used by authors and journals to standardize the quality of visual abstracts.


Assuntos
Publicações Periódicas como Assunto , Lista de Checagem , Humanos , Projetos de Pesquisa
3.
J Kidney Cancer VHL ; 8(4): 13-19, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722126

RESUMO

Advance diagnostic and treatment modalities have improved outcomes for renal cell carcinoma (RCC) patients, but the prognosis for those with metastatic disease (mRCC) remains poor. As given metastatic distribution is critical in guiding treatment decisions for mRCC patients, we evaluated evolving metastatic patterns to assess if our current practice standards effectively address patient needs. A systematic literature review was performed to identify all publicly available prospective clinical trials in metastatic renal cell carcinoma (mRCC) from 1990 to 2018. A total of 16,899 mRCC patients from 127 qualified phase I-III clinical trials with metastatic site documentations were included for analysis for incidence of metastases to lung, liver, bone, and lymph nodes (LNs) over time. Studies were categorized into three treatment eras based on the timing of regulatory approval: Cytokine Era (1990-2004), vascular endothelial growth factor/tyrosine kinase inhibitor (TKI) Era (2005-2016), and immune checkpoint inhibitor/TKI Era (ICI-TKI, 2017-2018) and also classified as first-line only (FLO) or second-line and beyond (SLB). Overall, an increase in the incidence of bone and LNs metastases in FLO and SLB, and lung metastases in FLO, was seen over the three treatment eras. Generally, the burden of disease is higher in SLB when compared with FLO. Importantly, in the ICI-TKI era, the incidences of bone metastasis are 28% in FLO and 29% in SLB settings. The disease burden in patients with mRCC has increased steadily over the past three decades. Given the unexpectedly high rate of bone metastasis, routine dedicated bone imaging should be considered in all patients with mRCC.

4.
Clin Genitourin Cancer ; 19(6): e346-e351, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34011488

RESUMO

BACKGROUND: Prostate-specific antigen (PSA) is a valuable prognostic and predictive biomarker in prostate cancer; however, the significance of PSA at or near the time of death is not well understood. This study aimed to characterize the significance of PSA at death in patients with metastatic castration-resistant prostate cancer (mCRPC). PATIENTS AND METHODS: The Mount Sinai Genitourinary Cancer Biorepository, an institutional review board-approved, single-institution database containing all consented genitourinary cancer patients seen between 2010 and 2018, was used to identify and stratify patients into the following cohorts based on their PSA at or near death: <100 ng/mL, 100-1000 ng/mL, and >1000 ng/mL. Analyses were performed to assess clinical characteristics of disease, treatment response, and outcomes. RESULTS: We identified 1097 patients with prostate cancer, and 101 were confirmed to be deceased following a diagnosis of mCRPC. In patients with mCRPC, cohorts of higher PSA level at death were associated with lower Gleason score at diagnosis and a trend toward longer time to mCRPC and longer time from diagnosis to death, despite a higher burden of disease at death. Conversely, subgroup analysis of PSA < 10 ng/mL at death was associated with lower rates of imaging within 6 months of death, lower treatment rate, and worse clinical outcomes. CONCLUSIONS: Cohorts of different PSA levels at death in mCRPC patients showed distinct patterns of disease characteristics and clinical outcomes, likely due to the underlying molecular phenotype differences. Imaging for the patient population with very low PSA levels may be underutilized and should be considered more routinely.


Assuntos
Antígeno Prostático Específico , Neoplasias de Próstata Resistentes à Castração , Humanos , Masculino , Gradação de Tumores , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento
5.
J Biol Chem ; 294(50): 19255-19268, 2019 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-31645432

RESUMO

MAF1 homolog, negative regulator of RNA polymerase III (MAF1) is a key repressor of RNA polymerase (pol) III-dependent transcription and functions as a tumor suppressor. Its expression is frequently down-regulated in primary human hepatocellular carcinomas (HCCs). However, this reduction in MAF1 protein levels does not correlate with its transcript levels, indicating that MAF1 is regulated post-transcriptionally. Here, we demonstrate that MAF1 is a labile protein whose levels are regulated through the ubiquitin-dependent proteasome pathway. We found that MAF1 ubiquitination is enhanced upon mTOR complex 1 (TORC1)-mediated phosphorylation at Ser-75. Moreover, we observed that the E3 ubiquitin ligase cullin 2 (CUL2) critically regulates MAF1 ubiquitination and controls its stability and subsequent RNA pol III-dependent transcription. Analysis of the phenotypic consequences of modulating either CUL2 or MAF1 protein expression revealed changes in actin cytoskeleton reorganization and altered sensitivity to doxorubicin-induced apoptosis. Repression of RNA pol III-dependent transcription by chemical inhibition or knockdown of BRF1 RNA pol III transcription initiation factor subunit (BRF1) enhanced HCC cell sensitivity to doxorubicin, suggesting that MAF1 regulates doxorubicin resistance in HCC by controlling RNA pol III-dependent transcription. Together, our results identify the ubiquitin proteasome pathway and CUL2 as important regulators of MAF1 levels. They suggest that decreases in MAF1 protein underlie chemoresistance in HCC and perhaps other cancers and point to an important role for MAF1 and RNA pol III-mediated transcription in chemosensitivity and apoptosis.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Doxorrubicina/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Repressoras/antagonistas & inibidores , Ubiquitina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Knockout , Fosforilação/efeitos dos fármacos , Proteínas Repressoras/deficiência , Proteínas Repressoras/metabolismo
6.
Environ Pollut ; 232: 494-504, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28993026

RESUMO

Potential adverse effects of human exposure to carbon black (CB) have been reported, but limited knowledge regarding CB-regulated metabolism is currently available. To evaluate how physical parameters of CB influence metabolism, we investigated CB and diesel exhaust particles (DEPs) and attempted to relate various physical parameters, including the hydrodynamic diameter, zeta potential, and particle number concentrations, to lung energy metabolism in female BALB/c mice. A body weight increase was arrested by 3 months of exposure to CB of smaller-size fractions, which was negatively correlated with pyruvate in plasma. There were no significant differences in cytotoxic lactate dehydrogenase (LDH) or total protein in bronchoalveolar lavage fluid (BALF) after 3 months of CB exposure. However, we observed alterations in acetyl CoA and the NADP/NADPH ratio in lung tissues with CB exposure. Additionally, the NADP/NADPH ratio was associated with the zeta potential of CB. Mild peribronchiovascular and interstitial inflammation and multinucleated giant cells (macrophages) with a transparent and rhomboid appearance and containing foreign bodies were observed in lung sections. We suggest that physical characteristics of CB, such as the zeta potential, may disrupt metabolism after pulmonary exposure. These results, therefore, provide the first evidence of a link between pulmonary exposure to CB and metabolism.


Assuntos
Poluentes Atmosféricos/toxicidade , Metabolismo/efeitos dos fármacos , Fuligem/toxicidade , Animais , Líquido da Lavagem Broncoalveolar , Carbono/metabolismo , Feminino , Humanos , Inflamação/metabolismo , Pulmão/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Emissões de Veículos/toxicidade
7.
Oncotarget ; 8(30): 48832-48845, 2017 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-28415573

RESUMO

The TATA-binding protein (TBP) plays a central role in eukaryotic gene transcription. Given its key function in transcription initiation, TBP was initially thought to be an invariant protein. However, studies showed that TBP expression is upregulated by oncogenic signaling pathways. Furthermore, depending on the cell type, small increases in cellular TBP amounts can induce changes in cellular growth properties towards a transformed phenotype. Here we sought to identify the specific TBP-regulated gene targets that drive its ability to induce tumorigenesis. Using microarray analysis, our results reveal that increases in cellular TBP concentrations produce selective alterations in gene expression that include an enrichment for genes involved in angiogenesis. Accordingly, we find that TBP levels modulate VEGFA expression, the master regulator of angiogenesis. Increases in cellular TBP amounts induce VEGFA expression and secretion to enhance cell migration and tumor vascularization. TBP mediates changes in VEGFA transcription requiring its recruitment at a hypoxia-insensitive proximal TSS, revealing a mechanism for VEGF regulation under non-stress conditions. The results are clinically relevant as TBP expression is significantly increased in both colon adenocarcinomas as well as adenomas relative to normal tissue. Furthermore, TBP expression is positively correlated with VEGFA expression. Collectively, these studies support the idea that increases in TBP expression contribute to enhanced VEGFA transcription early in colorectal cancer development to drive tumorigenesis.


Assuntos
Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteína de Ligação a TATA-Box/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Sítios de Ligação , Movimento Celular/genética , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Neoplasias do Colo/patologia , Expressão Gênica , Perfilação da Expressão Gênica , Genes Reporter , Humanos , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , RNA Polimerase II/metabolismo , Proteína de Ligação a TATA-Box/genética , Sítio de Iniciação de Transcrição , Transcriptoma , Fator A de Crescimento do Endotélio Vascular/metabolismo
8.
Cancer Res ; 76(7): 1954-64, 2016 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-26759245

RESUMO

Alterations in chromatin accessibility independent of DNA methylation can affect cancer-related gene expression, but are often overlooked in conventional epigenomic profiling approaches. In this study, we describe a cost-effective and computationally simple assay called AcceSssIble to simultaneously interrogate DNA methylation and chromatin accessibility alterations in primary human clear cell renal cell carcinomas (ccRCC). Our study revealed significant perturbations to the ccRCC epigenome and identified gene expression changes that were specifically attributed to the chromatin accessibility status whether or not DNA methylation was involved. Compared with commonly mutated genes in ccRCC, such as the von Hippel-Lindau (VHL) tumor suppressor, the genes identified by AcceSssIble comprised distinct pathways and more frequently underwent epigenetic changes, suggesting that genetic and epigenetic alterations could be independent events in ccRCC. Specifically, we found unique DNA methylation-independent promoter accessibility alterations in pathways mimicking VHL deficiency. Overall, this study provides a novel approach for identifying new epigenetic-based therapeutic targets, previously undetectable by DNA methylation studies alone, that may complement current genetic-based treatment strategies. Cancer Res; 76(7); 1954-64. ©2016 AACR.


Assuntos
Carcinoma de Células Renais/genética , Metilação de DNA/genética , Epigenômica/métodos , Carcinoma de Células Renais/patologia , Expressão Gênica , Humanos
9.
Artigo em Inglês | MEDLINE | ID: mdl-23840269

RESUMO

Drug resistance and tumor recurrence are major obstacles in treating lung cancer patients. Accumulating evidence considers lung cancer stem cells (CSCs) as the major contributor to these clinical challenges. Agents that can target lung CSCs could potentially provide a more effective treatment than traditional chemotherapy. Here, we utilized the side-population (SP) method to isolate lung CSCs from A549 and PC-9 cell lines. Subsequently, a high throughput platform, connectivity maps (CMAPs), was used to identify potential anti-CSC agents. An antibiotic, antimycin A (AMA), was identified as a top candidate. SP A549 cells exhibited an elevated stemness profile, including Nanog, ß -catenin, Sox2, and CD133, and increased self-renewal ability. AMA treatment was found to suppress ß -catenin signaling components and tumor sphere formation. Furthermore, AMA treatment decreased the proliferation of gefitinib-resistant PC-9/GR cells and percentage of SP population. AMA demonstrated synergistic suppression of PC-9/GR cell viability when combined with gefitinib. Finally, AMA treatment suppressed tumorigenesis in mice inoculated with A549 SP cells. Collectively, we have identified AMA using CMAP as a novel antilung CSC agent, which acts to downregulate ß -catenin signaling. The combination of AMA and targeted therapeutic agents could be considered for overcoming drug resistance and relapse in lung cancer patients.

10.
Mol Cancer ; 12: 59, 2013 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-23758962

RESUMO

BACKGROUND: Prolactin (PRL) is essential for normal mammary gland development. PRL promotes mammary tumor formation in rodents and elevated serum prolactin is associated with increased risk of estrogen-receptor positive breast cancer in women. On the other hand, PRL may also exert pro-differentiation effects and act to suppress invasive features of established breast cancer. Previously published limited global transcript profiling analyses of prolactin-regulated gene expression in human breast cancer cells have exclusively been performed in vitro. The present study aimed to shed new light on how PRL modulates estrogen receptor (ER)-positive breast cancer through global transcript profiling of a human breast cancer xenograft model in vivo. METHODS: The prolactin-responsive human T47D breast cancer cell line was xenotransplanted into nude mice and global transcript profiling was carried out following treatment with or without human PRL for 48 h. A subset of PRL-modulated transcripts was further validated using qRT-PCR and immunohistochemistry. RESULTS: The in vivo analyses identified 130 PRL-modulated transcripts, 75 upregulated and 55 downregulated, based on fold change >1.6 and P-value <0.05. From this initial panel of transcripts, a subset of 18 transcripts with established breast cancer-relevance were selected and validated by qRT-PCR. Some but not all of the transcripts were also PRL-modulated in vitro. The selected PRL-modulated transcripts were tested for dependence on Stat5, Jak1 or Jak2 activation, and for co-regulation by 17ß-estradiol (E2). The protein encoded by one of the PRL-regulated transcripts, PTHrP, was examined in a panel of 92 human breast cancers and found by in situ quantitative immunofluorescence analysis to be highly positively correlated with nuclear localized and tyrosine phosphorylated Stat5. Gene Ontology analysis revealed that PRL-upregulated genes were enriched in pathways involved in differentiation. Finally, a gene signature based on PRL-upregulated genes was associated with prolonged relapse-free and metastasis-free survival in breast cancer patients. CONCLUSIONS: This global analysis identified and validated a panel of PRL-modulated transcripts in an ER-positive human breast cancer xenotransplant model, which may have value as markers of relapse-free and metastasis-free survival. Gene products identified in the present study may facilitate ongoing deciphering of the pleiotropic effects of PRL on human breast cancer.


Assuntos
Neoplasias da Mama/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Prolactina/farmacologia , Animais , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Estradiol/farmacologia , Feminino , Ontologia Genética , Humanos , Janus Quinase 1/metabolismo , Janus Quinase 2/metabolismo , Camundongos Nus , Metástase Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Fosfotirosina/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Fator de Transcrição STAT5/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Methods Mol Biol ; 664: 45-52, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20690051

RESUMO

We present a protocol for construction of high-density tissue microarrays, cutting edge matrix assembly, which is based on repetitive sectioning and bonding of tissues. Maximized array density is achieved by a scaffold-free, self-supporting construction with rectangular array features that are bonded edge-to-edge, resulting in minimal wasted space between samples. Construction of the tissue array blocks from paraffin-embedded tissue involves initial bonding of primary tissue plates into multiple primary tissue stacks. This is achieved by taking a shaving of desired thickness from the face of each specimen block, trimming the shavings into a set of rectangular primary tissue plates, and bonding multiple plates into primary stacks of tissue. Each resulting primary tissue stack is then transversely cut to produce a set of secondary tissue plates that contains elements of each tissue represented in the primary stacks. Secondary plates from multiple primary sample stacks are then restacked and bonded into a secondary stack. The assembled secondary stack represents a laminate of laminates, which becomes the final array block. The final array block is then reembedded in paraffin and can be sectioned transversely using a microtome to yield micrometer thin sections that are transferred to glass slides for array display and analysis. This technology has facilitated the construction of arrays containing more than 10,000 tissue features on a standard glass slide.


Assuntos
Análise Serial de Tecidos/métodos , Neoplasias/patologia , Análise Serial de Tecidos/instrumentação
12.
Cancer Res ; 70(4): 1711-21, 2010 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20124477

RESUMO

BCL6 is a transcriptional repressor that recognizes DNA target sequences similar to those recognized by signal transducer and activator of transcriptions 5 (Stat5). BCL6 disrupts differentiation of breast epithelia, is downregulated during lactation, and is upregulated in poorly differentiated breast cancer. In contrast, Stat5a mediates prolactin-induced differentiation of mammary epithelia, and loss of Stat5 signaling in human breast cancer is associated with undifferentiated histology and poor prognosis. Here, we identify the mammary cell growth factor prolactin as a potent suppressor of BCL6 protein expression in human breast cancer through a mechanism that requires Stat5a, but not prolactin-activated Stat5b, MEK-ERK, or PI3K-AKT pathways. Prolactin rapidly suppressed BCL6 mRNA in T47D, MCF7, ZR75.1, and SKBr3 breast cancer cell lines, followed by prolonged reduction of BCL6 protein levels within 3 hours. Prolactin suppression of BCL6 was enhanced by overexpression of Stat5a but not Stat5b, was mimicked by constitutively active Stat5a, but did not require the transactivation domain of Stat5a. Stat5 chromatin immunoprecipitation demonstrated physical interaction with a BCL6 gene regulatory region, and BCL6 transcript repression required histone deacetylase activity based on sensitivity to trichostatin A. Functionally, BCL6 overexpression disrupted prolactin induction of Stat5 reporter genes. Prolactin suppression of BCL6 was extended to xenotransplant tumors in nude mice in vivo and to freshly isolated human breast cancer explants ex vivo. Quantitative immunohistochemistry revealed elevated BCL6 in high-grade and metastatic breast cancer compared with ductal carcinoma in situ and nonmalignant breast, and cellular BCL6 protein levels correlated negatively with nuclear Stat5a (r = -0.52; P < 0.001) but not with Stat5b. Loss of prolactin-Stat5a signaling and concomitant upregulation of BCL6 may represent a regulatory switch facilitating undifferentiated histology and poor prognosis of breast cancer.


Assuntos
Neoplasias da Mama/genética , Carcinoma/genética , Proteínas de Ligação a DNA/genética , Prolactina/farmacologia , Fator de Transcrição STAT5/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Animais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Carcinoma/diagnóstico , Carcinoma/patologia , Linhagem Celular Tumoral , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Nus , Prognóstico , Prolactina/fisiologia , Proteínas Proto-Oncogênicas c-bcl-6 , Fator de Transcrição STAT5/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Proteínas Supressoras de Tumor/genética , Ensaios Antitumorais Modelo de Xenoenxerto
13.
PLoS One ; 5(12): e15462, 2010 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-21203421

RESUMO

BACKGROUND: Establishing and maintaining polarization is critical during cell migration. It is known that the centrosome contains numerous proteins whose roles of organizing the microtubule network range include nucleation, stabilization and severing. It is not known whether the centrosome is necessary to maintain polarization. Due to its role as the microtubule organizing center, we hypothesize that the centrosome is necessary to maintain polarization in a migrating cell. Although there have been implications of its role in cell migration, there is no direct study of the centrosome's role in maintaining polarization. In this study we ablate the centrosome by intracellular laser irradiation to understand the role of the centrosome in two vastly different cell types, human osteosarcoma (U2OS) and rat kangaroo kidney epithelial cells (PtK). The PtK cell line has been extensively used as a model for cytoskeletal dynamics during cell migration. The U2OS cell line serves as a model for a complex, single migrating cell. METHODOLOGY/PRINCIPAL FINDINGS: In this study we use femtosecond near-infrared laser irradiation to remove the centrosome in migrating U2OS and PtK2 cells. Immunofluorescence staining for centrosomal markers verified successful irradiation with 94% success. A loss of cell polarization is observed between 30 and 90 minutes following removal of the centrosome. Changes in cell shape are correlated with modifications in microtubule and actin organization. Changes in cell morphology and microtubule organization were quantified revealing significant depolarization resulting from centrosome irradiation. CONCLUSIONS/SIGNIFICANCE: This study demonstrates that the centrosome is necessary for the maintenance of polarization during directed cell migration in two widely different cell types. Removal of the centrosome from a polarized cell results in the reorganization of the microtubule network into a symmetric non-polarized phenotype. These results demonstrate that the centrosome plays a critical role in the maintenance of cytoskeletal asymmetry during cell migration.


Assuntos
Centrossomo/ultraestrutura , Animais , Linhagem Celular Tumoral , Movimento Celular , Citoplasma/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Humanos , Lasers , Microscopia de Fluorescência/métodos , Microtúbulos/metabolismo , Osteossarcoma/metabolismo , Potoroidae
14.
Am J Pathol ; 174(4): 1172-90, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19342371

RESUMO

Caveolin-1 (Cav-1) loss-of-function mutations are exclusively associated with estrogen receptor-positive (ER(+)) human breast cancers. To dissect the role of Cav-1 loss-of-function in the pathogenesis of human breast cancers, we used Cav-1(-/-) null mice as a model system. First, we demonstrated that Cav-1(-/-) mammary epithelia overexpress two well-established ER co-activator genes, CAPER and Foxa1, in addition to ER-alpha. Thus, the functional loss of Cav-1 may be sufficient to confer estrogen-hypersensitivity in the mammary gland. To test this hypothesis directly, we subjected Cav-1(-/-) mice to ovariectomy and estrogen supplementation. As predicted, Cav-1(-/-) mammary glands were hyper-responsive to estrogen and developed dysplastic mammary lesions with adjacent stromal angiogenesis that resemble human ductal carcinoma in situ. Based on an extensive biomarker analysis, these Cav-1(-/-) mammary lesions contain cells that are hyperproliferative and stain positively with nucleolar (B23/nucleophosmin) and stem/progenitor cell markers (SPRR1A and beta-catenin). Genome-wide transcriptional profiling identified many estrogen-related genes that were over-expressed in Cav-1(-/-) mammary glands, including CAPER--an ER co-activator gene and putative stem/progenitor cell marker. Analysis of human breast cancer samples revealed that CAPER is overexpressed and undergoes a cytoplasmic-to-nuclear shift during the transition from pre-malignancy to ductal carcinoma in situ. Thus, Cav-1(-/-) null mice are a new preclinical model for studying the molecular paradigm of estrogen hypersensitivity and the development of estrogen-dependent ductal carcinoma in situ lesions.


Assuntos
Carcinoma Intraductal não Infiltrante/genética , Caveolina 1/genética , Estrogênios/farmacologia , Perfilação da Expressão Gênica , Neoplasias Mamárias Experimentais/genética , Animais , Carcinoma Intraductal não Infiltrante/metabolismo , Carcinoma Intraductal não Infiltrante/patologia , Caveolina 1/deficiência , Transformação Celular Neoplásica/genética , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Fator 3-alfa Nuclear de Hepatócito/genética , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Humanos , Imuno-Histoquímica , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Knockout , Análise de Sequência com Séries de Oligonucleotídeos , Ovariectomia , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Análise Serial de Tecidos , Transativadores/genética , Transativadores/metabolismo
15.
J Neurovirol ; 11(3): 281-91, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16036808

RESUMO

Cocaine is a suspected cofactor in human immunodeficiency virus (HIV)-associated dementia but cocaine's effects are not clear. Herein the authors describe investigations of the mechanisms by which cocaine increases HIV-1 invasion through brain microvascular endothelial cells (BMVECs). Cocaine binds to a site on BMVECs, which is not a biogenic amine transporter, a binding site for estrogen, or a muscarinic receptor and for which benztropine and tamoxifen have the highest affinity. Cocaine treatment of BMVECs disrupts intercellular junctions and induces cell ruffling, which could account for their increased permeability and decreased electrical resistance. HIV-1 enters BMVECs by macropinocytosis and is transported to lysosomes and inactivated. In cocaine-treated BMVECs, the virus enters and persists in large cytoplasmic "lakes." Cocaine exposure of BMVECs up-regulates transcription of genes important in cytoskeleton organization, signal transduction, cell swelling, vesicular trafficking, and cell adhesion. The toxicity of cocaine for the blood-brain barrier may lead to increased virus neuroinvasion and neurovascular complications of cocaine abuse.


Assuntos
Cocaína/farmacologia , HIV-1/fisiologia , Barreira Hematoencefálica/virologia , Encéfalo/irrigação sanguínea , Células Cultivadas , Cocaína/metabolismo , Relação Dose-Resposta a Droga , Impedância Elétrica , Endotélio Vascular/fisiologia , Endotélio Vascular/virologia , Humanos , Permeabilidade , Pinocitose , Receptores de Estrogênio/metabolismo , Receptores Muscarínicos/metabolismo , Transdução de Sinais , Fatores de Tempo , Replicação Viral/efeitos dos fármacos
16.
J Alzheimers Dis ; 7(3): 221-32; discussion 255-62, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16006665

RESUMO

The defective clearance of amyloid-beta (Abeta) in the brain of Alzheimer's disease (AD) patients is unexplained. The immunohistochemical studies of the frontal lobe and hippocampus show perivascular and intraplaque infiltration by blood-borne macrophages containing intracellular Abeta but only inefficient clearance of beta deposits. Neurons and neuronal nuclei, respectively, express interleukin-1beta and the chemokine RANTES, which could induce the inflammatory cell infiltration. To clarify the pathophysiology ofbeta clearance, we examined Abeta phagocytosis by monocytes and macrophages isolated from the blood of age-matched patients and controls. Control monocytes display excellent differentiation into macrophages and intracellular phagocytosis of Abeta followed by beta degradation or export. AD monocytes show poor differentiation and only surface uptake of Abeta and suffer apoptosis. HLA DR and cyclooxygenase-2 are abnormally expressed on neutrophils and monocytes of AD patients. AD patients have higher levels of intracellular cytokines compared to controls. Thus Abeta clearance is not restricted to brain microglia and involves systemic innate immune responses. In AD, however, macrophage phagocytosis is defective, which may elicit compensatory response by the adaptive immune system.


Assuntos
Doença de Alzheimer/imunologia , Peptídeos beta-Amiloides/metabolismo , Macrófagos/imunologia , Fagocitose/fisiologia , Idoso , Doença de Alzheimer/patologia , Apoptose/imunologia , Citocinas/metabolismo , Feminino , Lobo Frontal/imunologia , Lobo Frontal/patologia , Hipocampo/imunologia , Hipocampo/patologia , Humanos , Imunidade Inata/imunologia , Masculino , Microglia/imunologia , Microglia/patologia , Pessoa de Meia-Idade , Valores de Referência
17.
Am J Med ; 116(12): 829-34, 2004 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15178498

RESUMO

BACKGROUND: Natural history studies of hepatitis B virus infection have shown relapse of hepatitis in 5% to 15% of patients and progression to cirrhosis in 2% to 6% annually. Follow-up of patients beginning at the early phase of infection might provide data with less referral bias than in previous studies. METHODS: Test of liver biochemistry, assessment of virological markers, and ultrasound examinations were performed at regular intervals during the course of hepatitis B e antigen (HBeAg) to antibody (anti-HBe) seroconversion in 240 HBeAg carriers with normal alanine aminotransferase levels at baseline. Factors predictive of cirrhosis were identified by multivariate analysis. RESULTS: We enrolled 130 men and 110 women. The mean (+/- SD) age at entry was 27.6 +/- 6.2 years. During the HBeAg-positive phase, 29% of patients had alanine aminotransferase levels > or =200 U/L, 3% had bilirubin levels > or =2.0 mg/dL, and 5% had two or more episodes of alanine aminotransferase levels > or =200 U/L. The mean age at anti-HBe seroconversion was 31.3 +/- 7.0 years, with remission of hepatitis in all patients. However, hepatitis recurred in 36 patients (15%), with an annual rate of 2.2%. Thirteen patients (5%) progressed to cirrhosis. The annual incidence of cirrhosis was 0.5%, and the cumulative probability of cirrhosis after 17 years was 12.6%. Age at anti-HBe seroconversion and relapse of hepatitis were independent risk factors for cirrhosis. CONCLUSION: The clinical severity of chronic hepatitis B was milder in this cohort than in previous studies. Delayed HBeAg seroconversion and relapse of hepatitis were associated with increased risk of cirrhosis.


Assuntos
Anticorpos Anti-Hepatite B/imunologia , Antígenos E da Hepatite B/imunologia , Hepatite B/sangue , Hepatite B/imunologia , Transaminases/sangue , Adolescente , Adulto , Carcinoma Hepatocelular/etiologia , Feminino , Seguimentos , Hepatite B/complicações , Humanos , Cirrose Hepática/etiologia , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Valores de Referência
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