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1.
Alzheimers Res Ther ; 14(1): 93, 2022 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-35821150

RESUMO

BACKGROUND: About 40-50% of patients with amnestic mild cognitive impairment (MCI) are found to have no significant Alzheimer's pathology based on amyloid PET positivity. Notably, conversion to dementia in this population is known to occur much less often than in amyloid-positive MCI. However, the relationship between MCI and brain amyloid deposition remains largely unknown. Therefore, we investigated the influence of subthreshold levels of amyloid deposition on conversion to dementia in amnestic MCI patients with negative amyloid PET scans. METHODS: This study was a retrospective cohort study of patients with amyloid-negative amnestic MCI who visited the memory clinic of Asan Medical Center. All participants underwent detailed neuropsychological testing, brain magnetic resonance imaging, and [18F]-florbetaben (FBB) positron emission tomography scan (PET). Conversion to dementia was determined by a neurologist based on a clinical interview with a detailed neuropsychological test or a decline in the Korean version of the Mini-Mental State Examination score of more than 4 points per year combined with impaired activities of daily living. Regional cortical amyloid levels were calculated, and a receiver operating characteristic (ROC) curve for conversion to dementia was obtained. To increase the reliability of the results of the study, we analyzed the Alzheimer's Disease Neuroimaging Initiative (ADNI) dataset together. RESULTS: During the follow-up period, 36% (39/107) of patients converted to dementia from amnestic MCI. The dementia converter group displayed increased standardized uptake value ratio (SUVR) values of FBB on PET in the bilateral temporal, parietal, posterior cingulate, occipital, and left precuneus cortices as well as increased global SUVR. Among volume of interests, the left parietal SUVR predicted conversion to dementia with the highest accuracy in the ROC analysis (area under the curve [AUC] = 0.762, P < 0.001). The combination of precuneus, parietal cortex, and FBB composite SUVRs also showed a higher accuracy in predicting conversion to dementia than other models (AUC = 0.763). Of the results of ADNI data, the SUVR of the left precuneus SUVR showed the highest AUC (AUC = 0.596, P = 0.006). CONCLUSION: Our findings suggest that subthreshold amyloid levels may contribute to conversion to dementia in patients with amyloid-negative amnestic MCI.


Assuntos
Doença de Alzheimer , Amiloidose , Disfunção Cognitiva , Atividades Cotidianas , Doença de Alzheimer/patologia , Amiloide , Proteínas Amiloidogênicas , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Progressão da Doença , Humanos , Reprodutibilidade dos Testes , Estudos Retrospectivos
2.
Lymphat Res Biol ; 20(6): 640-650, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35584281

RESUMO

Background: Patients undergoing surgical treatment for solid tumors are at risk for development of secondary lymphedema due to intraoperative lymphatic vessel injury. The damaged lymphatic vessels fail to adequately regenerate and lymphatic obstruction leads to fluid and protein accumulation in the interstitial space and chronic lymphedema develops as a result. There are currently no effective pharmacological agents that reduce the risk of developing lymphedema or treat pre-existing lymphedema, and management is largely palliative. The present study investigated the efficacy of various 9-cis retinoic acid (9-cis RA) dosing strategies in reducing postsurgical lymphedema by utilizing a well-established mouse tail lymphedema model. Methods and Results: Short-duration treatment with 9-cis RA did not demonstrate a significant reduction in postoperative tail volume, nor an improvement in lymphatic clearance. However, long-term treatment with 9-cis RA resulted in decreased overall tail volume, dermal thickness, and epidermal thickness, with an associated increase in functional lymphatic clearance and lymphatic vessel density, assessed by LYVE-1 immunostaining, compared with control. These effects were seen at the site of lymphatic injury, with no significant changes observed in uninjured sites such as ear skin and the diaphragm. Conclusions: Given the reported results indicating that 9-cis RA is a potent promoter of lymphangiogenesis and improved lymphatic clearance at sites of lymphatic injury, investigation of postoperative 9-cis RA administration to patients at high risk of developing lymphedema may demonstrate positive efficacy and reduced rates of postsurgical lymphedema.


Assuntos
Vasos Linfáticos , Linfedema , Camundongos , Humanos , Animais , Duração da Terapia , Vasos Linfáticos/patologia , Alitretinoína/farmacologia , Linfangiogênese , Linfedema/patologia , Modelos Animais de Doenças
3.
BMC Gastroenterol ; 22(1): 85, 2022 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-35220946

RESUMO

AIM: To predict survival time of Korean hepatocellular carcinoma (HCC) patients using multi-center data as a foundation for the development of a predictive artificial intelligence model according to treatment methods based on machine learning. METHODS: Data of patients who underwent treatment for HCC from 2008 to 2015 was provided by Korean Liver Cancer Study Group and Korea Central Cancer Registry. A total of 10,742 patients with HCC were divided into two groups, with Group I (2920 patients) confirmed on biopsy and Group II (5562 patients) diagnosed as HCC according to HCC diagnostic criteria as outlined in Korean Liver Cancer Association guidelines. The data were modeled according to features of patient clinical characteristics. Features effective in predicting survival rate were analyzed retrospectively. Various machine learning methods were used. RESULTS: Target was overall survival time, which divided into approximately 60 months (= /< 60 m, > 60 m). Target distribution in Group I (total 514 samples) was 28.8%: (148 samples) less than 60 months, 71.2% (366 samples) greater than 60 months, and in Group II (total 757 samples) was 66.6% (504 samples) less than 60 months, 33.4% (253 samples) greater than 60 months. Using NG Boost method, its accuracy was 83%, precision 84%, sensitivity 95%, and F1 score 89% for more than 60 months survival time in Group I with surgical resection. Moreover, its accuracy was 79%, precision 82%, sensitivity 87%, and F1 score 84% for less than 60 months survival time in Group II with TACE. The feature importance with gain criterion indicated that pathology, portal vein invasion, surgery, metastasis, and needle biopsy features could be explained as important factors for prediction in case of biopsy (Group I). CONCLUSION: By developing a predictive model using machine learning algorithms to predict prognosis of HCC patients, it is possible to project optimized treatment by case according to liver function and tumor status.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Inteligência Artificial , Carcinoma Hepatocelular/patologia , Humanos , Neoplasias Hepáticas/patologia , Aprendizado de Máquina , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
4.
Int J Mol Sci ; 22(6)2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809794

RESUMO

In recent years, a major rise in the demand for biotherapeutic drugs has centered on enhancing the quality and efficacy of cell culture and developing new cell culture techniques. Here, we report fibronectin (FN) derived, novel peptides fibronectin-based intergrin binding peptide (FNIN)2 (18-mer) and FNIN3 (20-mer) which promote cell adhesion proliferation, and the differentiation of primary cells and stem cells. FNIN2 and 3 were designed based on the in silico interaction studies between FN and its receptors (integrin α5ß1, αvß3, and αIIbß3). Analysis of the proliferation of seventeen-cell types showed that the effects of FNINs depend on their concentration and the existence of expressed integrins. Significant rhodamine-labeled FNIN2 fluorescence on the membranes of HeLa, HepG2, A498, and Du145 cells confirmed physical binding. Double coating with FNIN2 or 3 after polymerized dopamine (pDa) or polymerized tannic acid (pTA) precoating increased HBEpIC cell proliferation by 30-40 percent, suggesting FNINs potently affect primary cells. Furthermore, the proliferation of C2C12 myoblasts and human mesenchymal stem cells (MSCs) treated with FNINs was significantly increased in 2D/3D culture. FNINs also promoted MSC differentiation into osteoblasts. The results of this study offer a new approach to the production of core materials (e.g., cell culture medium components, scaffolds) for cell culture.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Fibronectinas/química , Células-Tronco Mesenquimais/citologia , Peptídeos/farmacologia , Alginatos , Animais , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células HeLa , Humanos , Integrinas/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Modelos Moleculares , Osteogênese/efeitos dos fármacos , Domínios Proteicos , Ratos , Receptores de Superfície Celular/metabolismo
5.
Eur J Neurol ; 28(5): 1520-1527, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33559375

RESUMO

BACKGROUND AND PURPOSE: As part of network-specific neurodegeneration, changes in cerebellar gray matter (GM) volume and impaired cerebello-cerebral functional networks have been reported in Alzheimer disease (AD). Compared with healthy controls, a volume loss in the cerebellum has been observed in patients with continuum of AD. However, little is known about the anatomical or functional changes in patients with clinical AD but no brain amyloidosis. We aimed to identify the relationship between cerebellar volume and dementia conversion of amyloid-negative mild cognitive impairment (MCI). METHODS: This study was a retrospective cohort study of patients over the age 50 years with amyloid-negative amnestic MCI who visited the memory clinic of Asan Medical Center with no less than a 36-month follow-up period. All subjects underwent detailed neuropsychological tests, 3 T brain magnetic resonance imaging scans including three-dimensional T1 imaging, and fluorine-18[F18 ]-florbetaben amyloid positron emission tomography scans. A spatially unbiased atlas template of the cerebellum and brainstem was used for analyzing cerebellar GM volume. RESULTS: During the 36 months of follow-up, 39 of 107 (36.4%) patients converted to dementia from amnestic MCI. The converter group had more severe impairments in all visual memory tasks. In terms of volumetric analysis, reduced crus I/II volume adjusted with total intracranial volume, and age was observed in the converter group. CONCLUSIONS: Significant cerebellar GM atrophy involving the bilateral crus I/II may be a novel imaging biomarker for predicting dementia progression in amyloid-negative amnestic MCI patients.


Assuntos
Doença de Alzheimer , Amiloidose , Disfunção Cognitiva , Biomarcadores , Cerebelo , Disfunção Cognitiva/diagnóstico por imagem , Progressão da Doença , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons , Estudos Retrospectivos
6.
Int J Mol Sci ; 22(1)2020 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-33383646

RESUMO

Delta-like-ligand 4 (DLL4) is a promising target to augment the effects of VEGF inhibitors. A simultaneous blockade of VEGF/VEGFR and DLL4/Notch signaling pathways leads to more potent anti-cancer effects by synergistic anti-angiogenic mechanisms in xenograft models. A bispecific antibody targeting VEGF and DLL4 (ABL001/NOV1501/TR009) demonstrates more potent in vitro and in vivo biological activity compared to VEGF or DLL4 targeting monoclonal antibodies alone and is currently being evaluated in a phase 1 clinical study of heavy chemotherapy or targeted therapy pre-treated cancer patients (ClinicalTrials.gov Identifier: NCT03292783). However, the effects of a combination of ABL001 and chemotherapy on tumor vessels and tumors are not known. Hence, the effects of ABL001, with or without paclitaxel and irinotecan were evaluated in human gastric or colon cancer xenograft models. The combination treatment synergistically inhibited tumor progression compared to each monotherapy. More tumor vessel regression and apoptotic tumor cell induction were observed in tumors treated with the combination therapy, which might be due to tumor vessel normalization. Overall, these findings suggest that the combination therapy of ABL001 with paclitaxel or irinotecan would be a better clinical strategy for the treatment of cancer patients.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Anticorpos Biespecíficos/farmacologia , Proteínas de Ligação ao Cálcio/antagonistas & inibidores , Niacinamida/análogos & derivados , Pirazóis/farmacologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Anticorpos Biespecíficos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Modelos Animais de Doenças , Progressão da Doença , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Humanos , Camundongos , Neovascularização Patológica/tratamento farmacológico , Niacinamida/farmacologia , Niacinamida/uso terapêutico , Pirazóis/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Sci Rep ; 9(1): 13706, 2019 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-31548569

RESUMO

Human Oncostatin M (OSM), initially discovered as a tumour inhibitory factor secreted from U-937 cells, is a gp130 (IL-6/LIF) cytokine family member that exhibits pleiotropic effects in inflammation, haematopoiesis, skeletal tissue alteration, liver regeneration, cardiovascular and metabolic diseases. Cytoplasmic expression of OSM in Escherichia coli results in inclusion bodies, and complex solubilisation, refolding and purification is required to prepare bioactive protein. Herein, eight N-terminal fusion variants of OSM with hexahistidine (His6) tag and seven solubility-enhancing tags, including thioredoxin (Trx), small ubiquitin-related modifier (Sumo), glutathione S-transferase (GST), maltose-binding protein (MBP), N-utilisation substance protein A (Nusa), human protein disulphide isomerase (PDI) and the b'a' domain of PDI (PDIb'a'), were tested for soluble OSM expression in E. coli. The His6-OSM plasmid was also introduced into genetically engineered Origami 2 and SHuffle strains to test expression of the protein. At 18 °C, MBP-tagged OSM was highly expressed and solubility was dramatically enhanced. In addition, His6-OSM was more highly expressed and soluble in Origami 2 and SHuffle strains than in BL21(DE3). MBP-OSM and His6-OSM were purified more than 95% with yields of 11.02 mg and 3.27 mg from a 500 mL culture. Protein identity was confirmed by mass spectroscopy, and bioactivity was demonstrated by in vitro inhibition of Th17 cell differentiation.


Assuntos
Oncostatina M/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Escherichia coli , Expressão Gênica , Engenharia Genética , Histidina , Humanos , Proteínas Ligantes de Maltose/metabolismo , Oligopeptídeos , Oncostatina M/genética , Proteínas Recombinantes de Fusão/genética , Solubilidade
8.
BMB Rep ; 52(8): 496-501, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30670149

RESUMO

Conventionally, immunotoxins have been produced as a single polypeptide from fused genes of an antibody fragment and a toxin. In this study, we adopted a unique approach of chemical conjugation of a toxin protein and an antibody fragment. The two genes were separately expressed in Escherichia coli and purified to high levels of purity. The two purified proteins were conjugated using a chemical linker. The advantage of this approach is its ability to overcome the problem of low recombinant immunotoxin production observed in some immunotoxins. Another advantage is that various combinations of immunotoxins can be prepared with fewer efforts, because the chemical conjugation of components is relatively simpler than the processes involved in cloning, expression, and purification of multiple immunotoxins. As a proof of concept, the scFv of trastuzumab and the PE24 fragment of Pseudomonas exotoxin A were separately produced using E. coli and then chemically crosslinked. The new immunotoxin was tested on four breast cancer cell lines variably expressing HER2. The chemically crosslinked immunotoxin exhibited cytotoxicity in proportion to the expression level of HER2. In conclusion, the present study revealed an alternative method of generating an immunotoxin that could effectively reduce the viability of HER2-expressing breast cancer cells. These results suggest the effectiveness of this method of immunotoxin crosslinking as a suitable alternative for producing immunotoxins. [BMB Reports 2019; 52(8): 496-501].


Assuntos
ADP Ribose Transferases/farmacologia , Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Toxinas Bacterianas/farmacologia , Neoplasias da Mama/tratamento farmacológico , Exotoxinas/farmacologia , Receptor ErbB-2/antagonistas & inibidores , Fatores de Virulência/farmacologia , ADP Ribose Transferases/química , ADP Ribose Transferases/metabolismo , Anticorpos Monoclonais/química , Anticorpos Monoclonais/metabolismo , Antineoplásicos/química , Toxinas Bacterianas/química , Toxinas Bacterianas/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Exotoxinas/química , Exotoxinas/metabolismo , Feminino , Humanos , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Fatores de Virulência/química , Fatores de Virulência/metabolismo , Exotoxina A de Pseudomonas aeruginosa
9.
JCI Insight ; 4(5)2019 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-30676326

RESUMO

The lymphatic system plays crucial roles in tissue homeostasis, lipid absorption, and immune cell trafficking. Although lymphatic valves ensure unidirectional lymph flows, the flow itself controls lymphatic valve formation. Here, we demonstrate that a mechanically activated ion channel Piezo1 senses oscillating shear stress (OSS) and incorporates the signal into the genetic program controlling lymphatic valve development and maintenance. Time-controlled deletion of Piezo1 using a pan-endothelial Cre driver (Cdh5[PAC]-CreERT2) or lymphatic-specific Cre driver (Prox1-CreERT2) equally inhibited lymphatic valve formation in newborn mice. Furthermore, Piezo1 deletion in adult lymphatics caused substantial lymphatic valve degeneration. Piezo1 knockdown in cultured lymphatic endothelial cells (LECs) largely abrogated the OSS-induced upregulation of the lymphatic valve signature genes. Conversely, ectopic Piezo1 overexpression upregulated the lymphatic valve genes in the absence of OSS. Remarkably, activation of Piezo1 using chemical agonist Yoda1 not only accelerated lymphatic valve formation in animals, but also triggered upregulation of some lymphatic valve genes in cultured LECs without exposure to OSS. In summary, our studies together demonstrate that Piezo1 is the force sensor in the mechanotransduction pathway controlling lymphatic valve development and maintenance, and Piezo1 activation is a potentially novel therapeutic strategy for congenital and surgery-associated lymphedema.


Assuntos
Canais Iônicos/metabolismo , Linfangiogênese/genética , Linfangiogênese/fisiologia , Vasos Linfáticos/metabolismo , Transcriptoma , Animais , Antígenos CD , Caderinas , Células Endoteliais/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Canais Iônicos/genética , Vasos Linfáticos/patologia , Mecanotransdução Celular/fisiologia , Camundongos , Camundongos Knockout , Modelos Animais , Estresse Mecânico , Regulação para Cima
10.
Environ Pollut ; 233: 855-861, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29248762

RESUMO

Knowledge of environmental risk factors for stroke and their role are limited. We performed a case-cohort study to evaluate the association between serum persistent organic pollutants (POPs) level and stroke risk. 526 subcohort members and 111 stroke incidence cases were identified from the Korean Cancer Prevention Study-II. Serum levels of POPs were measured using gas chromatography/high-resolution mass spectrometry. The hazard ratios (HRs) for stroke (ischemic, hemorrhagic, and all stroke types) were estimated using the weighted Cox regression model. Age, sex, body mass index, smoking status, physical activity, family history of cardiovascular disease, and hypertension were adjusted in the weighted Cox regression model. After adjusting for potential confounding factors, increased risk for stroke was observed among participants with serum concentration of p,p'-DDE in the highest tertile compared to those in the lowest tertile (HR = 4.10, 95% CI: 1.58, 10.59). A similar association was estimated for PCB118 (HR = 2.33, 95% CI: 1.04, 5.22), PCB156 (HR = 3.42, 95% CI: 1.42, 8.23), and PCB138 (HR = 3.80, 95% CI: 1.48, 9.76). For TEQ, stroke was three times as likely to occur among subjects with TEQ in the highest tertile compared to those in the lowest tertile (HR = 3.12, 95% CI: 1.27, 7.65). PCBs were positively associated with ischemic stroke, but not with hemorrhagic stroke. Elevated serum POPs levels were associated with an increased risk of stroke, especially ischemic stroke.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/sangue , Acidente Vascular Cerebral/epidemiologia , Adulto , Isquemia Encefálica , Estudos de Coortes , Diclorodifenil Dicloroetileno/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hipertensão , Masculino , Pessoa de Meia-Idade , Bifenilos Policlorados/sangue , Modelos de Riscos Proporcionais , República da Coreia/epidemiologia , Risco , Fumar/epidemiologia
11.
J Microbiol Biotechnol ; 27(12): 2156-2164, 2017 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-29032646

RESUMO

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is considered as an antitumor agent owing to its ability to induce apoptosis of cancer cells without imparting toxicity toward most normal cells. TRAIL is produced in poor yield because of its insoluble expression in the cytoplasm of E. coli. In this study, we achieved soluble expression of TRAIL by fusing maltose-binding protein (MBP), b'a' domain of protein disulfide isomerase (PDIb'a'), or protein disulfide isomerase at the N-terminus of TRAIL. The TRAIL was purified using subsequent immobilized metal affinity chromatography and amylose-binding chromatography, with the tag removal using tobacco etch virus protease. Approximately 4.5 mg of pure TRAIL was produced from 125 ml flask culture with a purification yield of 71.6%. The endotoxin level of the final product was 0.4 EU/µg, as measured by the Limulus amebocyte lysate endotoxin assay. The purified TRAIL was validated and shown to cause apoptosis of HeLa cells with an EC50 and Hill coefficient of 0.6 ± 0.03 nM and 2.41 ± 0.15, respectively. The high level of apoptosis in HeLa cells following administration of purified TRAIL indicates the significance and novelty of this method for producing high-grade and high-yield TRAIL.


Assuntos
Ligante Indutor de Apoptose Relacionado a TNF/biossíntese , Antineoplásicos/farmacologia , Apoptose , Cromatografia de Afinidade , Escherichia coli/genética , Escherichia coli/metabolismo , Células HeLa , Humanos , Proteínas Ligantes de Maltose/genética , Isomerases de Dissulfetos de Proteínas/genética , Solubilidade , Ligante Indutor de Apoptose Relacionado a TNF/genética
12.
Sci Rep ; 7(1): 5577, 2017 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-28717161

RESUMO

The lymphatic system plays a key role in tissue fluid homeostasis, immune cell trafficking, and fat absorption. We previously reported a bacterial artificial chromosome (BAC)-based lymphatic reporter mouse, where EGFP is expressed under the regulation of the Prox1 promoter. This reporter line has been widely used to conveniently visualize lymphatic vessels and other Prox1-expressing tissues such as Schlemm's canal. However, mice have a number of experimental limitations due to small body size. By comparison, laboratory rats are larger in size and more closely model the metabolic, physiological, and surgical aspects of humans. Here, we report development of a novel lymphatic reporter rat using the mouse Prox1-EGFP BAC. Despite the species mismatch, the mouse Prox1-EGFP BAC enabled a reliable expression of EGFP in Prox1-expressing cells of the transgenic rats and allowed a convenient visualization of all lymphatic vessels, including those in the central nervous system, and Schlemm's canal. To demonstrate the utility of this new reporter rat, we studied the contractile properties and valvular functions of mesenteric lymphatics, developed a surgical model for vascularized lymph node transplantation, and confirmed Prox1 expression in venous valves. Together, Prox1-EGFP rat model will contribute to the advancement of lymphatic research as a valuable experimental resource.


Assuntos
Cromossomos Artificiais Bacterianos/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Homeodomínio/genética , Vasos Linfáticos/metabolismo , Regiões Promotoras Genéticas , Proteínas Supressoras de Tumor/genética , Animais , Tamanho Corporal , Sistema Nervoso Central/imunologia , Olho/imunologia , Regulação da Expressão Gênica , Humanos , Camundongos , Modelos Animais , Ratos , Ratos Transgênicos
13.
Sci Rep ; 7(1): 6480, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28744022

RESUMO

Human granulocyte colony-stimulating factor (GCSF) is a well-known cytokine for neutropenia treatment. However, daily injections are required due to the short circulating half-life of the protein. To overcome this bottleneck, we fused GCSF with the Fc domain of IgG1 at the C terminus (GCSF-Fc) and with the maltose binding protein (MBP) tag at the N-terminus and expressed it as a soluble protein in the cytoplasm of E. coli. We also conjugated PEG aldehyde to GCSF to make PEG-GCSF. The bioactivities of GCSF-Fc and PEG-GCSF were similar to native GCSF using the mouse M-NFS-60 myelogenous leukemia cell line. The EC50 dose-response curves for GCSF, GCSF-Fc and PEG-GCSF were 37 ± 12 pM, 75 ± 13.5 pM and 46 ± 5.5 pM, respectively. When the proteins were injected into neutropenic rats, the group injected with PEG-GCSF showed the highest and fastest recovery of neutrophils, followed by GCSF-Fc and GCSF. ELISA assay revealed the PEG-GCSF had the longest plasma circulation (>72 h), followed by GCSF-Fc (>48 h) and GCSF (~24 h), which is consistent with the in vivo activities of the proteins. In summary, the GCSF-Fc purified from E. coli was not as efficient as PEG-GCSF in treating neutropenic rats.


Assuntos
Fator Estimulador de Colônias de Granulócitos/genética , Fator Estimulador de Colônias de Granulócitos/farmacologia , Fragmentos Fc das Imunoglobulinas/genética , Polietilenoglicóis/química , Proteínas Recombinantes/farmacologia , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Escherichia coli/genética , Humanos , Concentração de Íons de Hidrogênio , Neutropenia/tratamento farmacológico , Polietilenoglicóis/farmacologia , Engenharia de Proteínas/métodos , Ratos Sprague-Dawley , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação
14.
Sci Rep ; 7(1): 3876, 2017 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-28634413

RESUMO

Wound healing is significantly delayed in irradiated skin. To better understand global changes in protein expression after radiation, we utilized a reverse phase protein array (RPPA) to identify significant changes in paired samples of normal and irradiated human skin. Of the 210 proteins studied, fibronectin was the most significantly and consistently downregulated in radiation-damaged skin. Using a murine model, we confirmed that radiation leads to decreased fibronectin expression in the skin as well as delayed wound healing. Topically applied fibronectin was found to significantly improve wound healing in irradiated skin and was associated with decreased inflammatory infiltrate and increased angiogenesis. Fibronectin treatment may be a useful adjunctive modality in the treatment of non-healing radiation wounds.


Assuntos
Fibronectinas/administração & dosagem , Lesões por Radiação/patologia , Pele/efeitos dos fármacos , Pele/lesões , Cicatrização , Administração Tópica , Animais , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Análise Serial de Proteínas , Lesões por Radiação/tratamento farmacológico , Lesões por Radiação/metabolismo , Pele/metabolismo , Pele/patologia
15.
J Clin Invest ; 127(4): 1225-1240, 2017 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-28263185

RESUMO

The major function of the lymphatic system is to drain interstitial fluid from tissue. Functional drainage causes increased fluid flow that triggers lymphatic expansion, which is conceptually similar to hypoxia-triggered angiogenesis. Here, we have identified a mechanotransduction pathway that translates laminar flow-induced shear stress to activation of lymphatic sprouting. While low-rate laminar flow commonly induces the classic shear stress responses in blood endothelial cells and lymphatic endothelial cells (LECs), only LECs display reduced Notch activity and increased sprouting capacity. In response to flow, the plasma membrane calcium channel ORAI1 mediates calcium influx in LECs and activates calmodulin to facilitate a physical interaction between Krüppel-like factor 2 (KLF2), the major regulator of shear responses, and PROX1, the master regulator of lymphatic development. The PROX1/KLF2 complex upregulates the expression of DTX1 and DTX3L. DTX1 and DTX3L, functioning as a heterodimeric Notch E3 ligase, concertedly downregulate NOTCH1 activity and enhance lymphatic sprouting. Notably, overexpression of the calcium reporter GCaMP3 unexpectedly inhibited lymphatic sprouting, presumably by disturbing calcium signaling. Endothelial-specific knockouts of Orai1 and Klf2 also markedly impaired lymphatic sprouting. Moreover, Dtx3l loss of function led to defective lymphatic sprouting, while Dtx3l gain of function rescued impaired sprouting in Orai1 KO embryos. Together, the data reveal a molecular mechanism underlying laminar flow-induced lymphatic sprouting.


Assuntos
Sinalização do Cálcio/fisiologia , Regulação para Baixo/fisiologia , Linfangiogênese/fisiologia , Receptor Notch1/biossíntese , Animais , Velocidade do Fluxo Sanguíneo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células Endoteliais/citologia , Células HEK293 , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Camundongos , Camundongos Knockout , Proteína ORAI1/genética , Proteína ORAI1/metabolismo , Receptor Notch1/genética , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
16.
Circ Res ; 120(9): 1426-1439, 2017 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-28167653

RESUMO

RATIONALE: Lymphatic vessels function to drain interstitial fluid from a variety of tissues. Although shear stress generated by fluid flow is known to trigger lymphatic expansion and remodeling, the molecular basis underlying flow-induced lymphatic growth is unknown. OBJECTIVE: We aimed to gain a better understanding of the mechanism by which laminar shear stress activates lymphatic proliferation. METHODS AND RESULTS: Primary endothelial cells from dermal blood and lymphatic vessels (blood vascular endothelial cells and lymphatic endothelial cells [LECs]) were exposed to low-rate steady laminar flow. Shear stress-induced molecular and cellular responses were defined and verified using various mutant mouse models. Steady laminar flow induced the classic shear stress responses commonly in blood vascular endothelial cells and LECs. Surprisingly, however, only LECs showed enhanced cell proliferation by regulating the vascular endothelial growth factor (VEGF)-A, VEGF-C, FGFR3, and p57/CDKN1C genes. As an early signal mediator, ORAI1, a pore subunit of the calcium release-activated calcium channel, was identified to induce the shear stress phenotypes and cell proliferation in LECs responding to the fluid flow. Mechanistically, ORAI1 induced upregulation of Krüppel-like factor (KLF)-2 and KLF4 in the flow-activated LECs, and the 2 KLF proteins cooperate to regulate VEGF-A, VEGF-C, FGFR3, and p57 by binding to the regulatory regions of the genes. Consistently, freshly isolated LECs from Orai1 knockout embryos displayed reduced expression of KLF2, KLF4, VEGF-A, VEGF-C, and FGFR3 and elevated expression of p57. Accordingly, mouse embryos deficient in Orai1, Klf2, or Klf4 showed a significantly reduced lymphatic density and impaired lymphatic development. CONCLUSIONS: Our study identified a molecular mechanism for laminar flow-activated LEC proliferation.


Assuntos
Proliferação de Células , Células Endoteliais/metabolismo , Endotélio Linfático/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Linfangiogênese , Mecanotransdução Celular , Proteína ORAI1/metabolismo , Animais , Inibidor de Quinase Dependente de Ciclina p57/genética , Inibidor de Quinase Dependente de Ciclina p57/metabolismo , Endotélio Linfático/patologia , Endotélio Linfático/fisiopatologia , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica , Genótipo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/deficiência , Fatores de Transcrição Kruppel-Like/genética , Camundongos Knockout , Proteína ORAI1/deficiência , Proteína ORAI1/genética , Fenótipo , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/metabolismo , Estresse Mecânico , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator C de Crescimento do Endotélio Vascular/genética , Fator C de Crescimento do Endotélio Vascular/metabolismo
17.
Cancer Res ; 76(3): 582-93, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26609053

RESUMO

Papillary thyroid cancer (PTC) is one of the most common endocrine malignancies associated with significant morbidity and mortality. Although multiple studies have contributed to a better understanding of the genetic alterations underlying this frequently arising disease, the downstream molecular effectors that impact PTC pathogenesis remain to be further defined. Here, we report that the regulator of cell fate specification, PROX1, becomes inactivated in PTC through mRNA downregulation and cytoplasmic mislocalization. Expression studies in clinical specimens revealed that aberrantly activated NOTCH signaling promoted PROX1 downregulation and that cytoplasmic mislocalization significantly altered PROX1 protein stability. Importantly, restoration of PROX1 activity in thyroid carcinoma cells revealed that PROX1 not only enhanced Wnt/ß-catenin signaling but also regulated several genes known to be associated with PTC, including thyroid cancer protein (TC)-1, SERPINA1, and FABP4. Furthermore, PROX1 reexpression suppressed the malignant phenotypes of thyroid carcinoma cells, such as proliferation, motility, adhesion, invasion, anchorage-independent growth, and polyploidy. Moreover, animal xenograft studies demonstrated that restoration of PROX1 severely impeded tumor formation and suppressed the invasiveness and the nuclear/cytoplasmic ratio of PTC cells. Taken together, our findings demonstrate that NOTCH-induced PROX1 inactivation significantly promotes the malignant behavior of thyroid carcinoma and suggest that PROX1 reactivation may represent a potential therapeutic strategy to attenuate disease progression.


Assuntos
Carcinoma/metabolismo , Carcinoma/patologia , Proteínas de Homeodomínio/antagonistas & inibidores , Receptores Notch/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Proteínas Supressoras de Tumor/antagonistas & inibidores , Animais , Carcinoma/genética , Carcinoma Papilar , Proliferação de Células/fisiologia , Regulação para Baixo , Expressão Gênica , Proteínas de Homeodomínio/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Receptores Notch/genética , Transdução de Sinais , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/genética , Proteínas Supressoras de Tumor/metabolismo
18.
Int Braz J Urol ; 40(3): 356-66, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25010301

RESUMO

PURPOSE: To evaluate the association between prostatic inflammation and lower urinary tract symptoms (LUTS), and to identify the effects of prostatic inflammation on the treatment with an alpha blocker. MATERIALS AND METHODS: 111 Participants who were aged ≥ 50 years, the presence of LUTS (maximal flow rate < 20 m/s, IPSS ≥ 11), and an elevated PSA level (3-20 ng/mL) were treated with tamsulosin 0.2mg once daily for 3 months after prostate biopsies. Prostatic inflammation was scored as none (0), mild (I), moderate (II), or marked (III). LUTS parameters including urine flow rates, IPSS, PSA, and prostate volume were evaluated. RESULTS: Inflammation grading resulted in 25, 60, and 26 patients that were grade 0, I, and II, respectively. Lower grade inflammation was related to higher urine flow rate at baseline. Patients with higher inflammation grades had larger prostate volumes, larger total and transitional zone volumes, and higher PSA levels. Overall, urine flow rates and residual urine volume were improved after 3 months of alpha blocker therapy. Eighty percent of patients with grade 0 inflammation, 73% of patients with grade I inflammation, and 92.3% of patients with grade II inflammation showed improvement of LUTS after treatment. Longer duration of treatment was related to a decreased chance of improvement of LUTS. Patients with increased IPSS voiding subscales could be predictive of improvement of LUTS. CONCLUSIONS: Patients with high grade inflammation had lower flow rates and higher prostatic volumes than patients with low grade inflammation. Inflammation grade did not affect the outcomes of alpha blocker treatment.


Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1/uso terapêutico , Sintomas do Trato Urinário Inferior/tratamento farmacológico , Hiperplasia Prostática/tratamento farmacológico , Prostatite/tratamento farmacológico , Sulfonamidas/uso terapêutico , Idoso , Biópsia , Progressão da Doença , Humanos , Sintomas do Trato Urinário Inferior/patologia , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Valor Preditivo dos Testes , Antígeno Prostático Específico/sangue , Hiperplasia Prostática/patologia , Prostatite/complicações , Prostatite/patologia , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Tansulosina , Resultado do Tratamento
19.
J Clin Invest ; 124(9): 3960-74, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25061877

RESUMO

Schlemm's canal (SC) is a specialized vascular structure in the eye that functions to drain aqueous humor from the intraocular chamber into systemic circulation. Dysfunction of SC has been proposed to underlie increased aqueous humor outflow (AHO) resistance, which leads to elevated ocular pressure, a factor for glaucoma development in humans. Here, using lymphatic and blood vasculature reporter mice, we determined that SC, which originates from blood vessels during the postnatal period, acquires lymphatic identity through upregulation of prospero homeobox protein 1 (PROX1), the master regulator of lymphatic development. SC expressed lymphatic valve markers FOXC2 and integrin α9 and exhibited continuous vascular endothelial-cadherin (VE-cadherin) junctions and basement membrane, similar to collecting lymphatics. SC notably lacked luminal valves and expression of the lymphatic endothelial cell markers podoplanin and lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1). Using an ocular puncture model, we determined that reduced AHO altered the fate of SC both during development and under pathologic conditions; however, alteration of VEGF-C/VEGFR3 signaling did not modulate SC integrity and identity. Intriguingly, PROX1 expression levels linearly correlated with SC functionality. For example, PROX1 expression was reduced or undetectable under pathogenic conditions and in deteriorated SCs. Collectively, our data indicate that PROX1 is an accurate and reliable biosensor of SC integrity and identity.


Assuntos
Humor Aquoso/fisiologia , Córnea/irrigação sanguínea , Proteínas de Homeodomínio/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Actinas/análise , Animais , Células Endoteliais/fisiologia , Transição Epitelial-Mesenquimal , Pressão Intraocular , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Morfogênese , Fator C de Crescimento do Endotélio Vascular/fisiologia , Receptor 3 de Fatores de Crescimento do Endotélio Vascular/fisiologia
20.
Int. braz. j. urol ; 40(3): 356-366, may-jun/2014. tab
Artigo em Inglês | LILACS | ID: lil-718254

RESUMO

Purpose To evaluate the association between prostatic inflammation and lower urinary tract symptoms (LUTS), and to identify the effects of prostatic inflammation on the treatment with an alpha blocker. Materials and Methods 111 Participants who were aged ≥ 50 years, the presence of LUTS (maximal flow rate < 20 m/s, IPSS ≥ 11), and an elevated PSA level (3-20ng/mL) were treated with tamsulosin 0.2mg once daily for 3 months after prostate biopsies. Prostatic inflammation was scored as none (0), mild (I), moderate (II), or marked (III). LUTS parameters including urine flow rates, IPSS, PSA, and prostate volume were evaluated. Results Inflammation grading resulted in 25, 60, and 26 patients that were grade 0, I, and II, respectively. Lower grade inflammation was related to higher urine flow rate at baseline. Patients with higher inflammation grades had larger prostate volumes, larger total and transitional zone volumes, and higher PSA levels. Overall, urine flow rates and residual urine volume were improved after 3 months of alpha blocker therapy. Eighty percent of patients with grade 0 inflammation, 73% of patients with grade I inflammation, and 92.3% of patients with grade II inflammation showed improvement of LUTS after treatment. Longer duration of treatment was related to a decreased chance of improvement of LUTS. Patients with increased IPSS voiding subscales could be predictive of improvement of LUTS. Conclusions Patients with high grade inflammation had lower flow rates and higher prostatic volumes than patients with low grade inflammation. Inflammation grade did not affect the outcomes of alpha blocker treatment. .


Assuntos
Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Antagonistas de Receptores Adrenérgicos alfa 1/uso terapêutico , Sintomas do Trato Urinário Inferior/tratamento farmacológico , Hiperplasia Prostática/tratamento farmacológico , Prostatite/tratamento farmacológico , Sulfonamidas/uso terapêutico , Biópsia , Progressão da Doença , Sintomas do Trato Urinário Inferior/patologia , Tamanho do Órgão , Valor Preditivo dos Testes , Antígeno Prostático Específico/sangue , Hiperplasia Prostática/patologia , Prostatite/complicações , Prostatite/patologia , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Resultado do Tratamento
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