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1.
Methods Mol Biol ; 2773: 25-32, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38236533

RESUMO

Urinary bladder cancer is the tenth most common cancer worldwide with high morbidity and mortality. The majority of bladder cancers are urothelial carcinomas. More than half are papillomas or the papillary urothelial carcinomas (stages Ta and T1), which have a relatively good prognosis. Squamous cell carcinomas have a variable survival rate, while carcinomas in situ (Tis) can progress to muscle-invasive urothelial carcinomas (T2) with a poor prognosis. The most challenging feature of bladder cancer is its high recurrence rate, ranging from 50% to 90% of cases. The N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) model is an invaluable experimental tool for bladder cancer research, as BBN-induced bladder cancer in rodents resembles human bladder cancer in its morphological, biological, and molecular features. We present here a detailed protocol for the treatment of mice and the main expected results.


Assuntos
Carcinoma de Células Escamosas , Nitrosaminas , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/induzido quimicamente , Bexiga Urinária , Músculos
2.
Histochem Cell Biol ; 160(5): 435-452, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37535087

RESUMO

Urinary bladder cancer can be treated by intravesical application of therapeutic agents, but the specific targeting of cancer urothelial cells and the endocytotic pathways of the agents are not known. During carcinogenesis, the superficial urothelial cells exhibit changes in sugar residues on the apical plasma membranes. This can be exploited for selective targeting from the luminal side of the bladder. Here we show that the plant lectins Jacalin (from Artocarpus integrifolia), ACA (from Amaranthus caudatus) and DSA (from Datura stramonium) selectively bind to the apical plasma membrane of low- (RT4) and high-grade (T24) cancer urothelial cells in vitro and urothelial tumours ex vivo. The amount of lectin binding was significantly different between RT4 and T24 cells. Endocytosis of lectins was observed only in cancer urothelial cells and not in normal urothelial cells. Transmission electron microscopy analysis showed macropinosomes, endosome-like vesicles and multivesicular bodies filled with lectins in RT4 and T24 cells and also in cells of urothelial tumours ex vivo. Endocytosis of Jacalin and ACA in cancer cells was decreased in vitro after addition of inhibitor of macropinocytosis 5-(N-ethyl-N-isopropyl) amiloride (EIPA) and increased after stimulation of macropinocytosis with epidermal growth factor (EGF). Clathrin, caveolin and flotillin did not colocalise with lectins. These results confirm that the predominant mechanism of lectin endocytosis in cancer urothelial cells is macropinocytosis. Therefore, we propose that lectins in combination with conjugated therapeutic agents are promising tools for improved intravesical therapy by targeting cancer cells.


Assuntos
Lectinas , Neoplasias da Bexiga Urinária , Humanos , Lectinas/metabolismo , Neoplasias da Bexiga Urinária/patologia , Endocitose/fisiologia , Bexiga Urinária/metabolismo , Endossomos/metabolismo , Lectinas de Plantas/farmacologia , Lectinas de Plantas/metabolismo , Lectinas de Plantas/uso terapêutico
3.
Heliyon ; 9(5): e15674, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37131433

RESUMO

Glioblastoma is one of the deadliest cancers, therefore novel efficient therapeutic approaches are urgently required. One of such are nanobodies, prospective nano-sized bio-drugs with advantageous characteristics. Nanobodies can target intracellular proteins, but to increase their efficiency, the delivery system should be applied. Here, we examined small extracellular vesicles as a delivery system for anti-vimentin nanobody Nb79. Nb79 was loaded in small extracellular vesicles either by incubation with glioblastoma cells, by passive loading into isolated small extracellular vesicles or by sonication of isolated small extracellular vesicles. Small extracellular vesicles secreted by glioblastoma cells were isolated by ultracentrifugation on sucrose cushion. The size distribution and average size of sonicated and non-sonicated small extracellular vesicles were determined by nanoparticle tracking analysis method. The loading of Nb79 into small extracellular vesicles by incubation with cells, passive loading or sonication was confirmed by Western blot and electron microscopy. The effect of small extracellular vesicles on cell survival was determined by WST-1 reagent. Loading of small extracellular vesicles by incubation of cells with Nb79 was unsuccessful and resulted in substantial cell death. On the other hand, as confirmed by Western blot and electron microscopy, sonication is a successful method for obtaining Nb79-loaded small extracellular vesicles. Small extracellular vesicles also had an effect on cell viability. Small extracellular vesicles without Nb79 increased survival of U251 and NCH644 cells for 20-25%, while the Nb79-loaded small extracellular vesicles decreased survival of NCH421k by 11%. We demonstrated that sonication is a suitable method to load nanobodies into exosome, and these small extracellular vesicles could in turn reduce cell survival. The method could be translated also to other applications, such as targeted delivery system of other protein-based drugs.

4.
Int J Mol Sci ; 24(5)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36902479

RESUMO

Several animal studies have described the potential effect of cannabidiol (CBD) in alleviating the symptoms of interstitial cystitis/bladder pain syndrome (IC/BPS), a chronic inflammatory disease of the urinary bladder. However, the effects of CBD, its mechanism of action, and modulation of downstream signaling pathways in urothelial cells, the main effector cells in IC/BPS, have not been fully elucidated yet. Here, we investigated the effect of CBD against inflammation and oxidative stress in an in vitro model of IC/BPS comprised of TNFα-stimulated human urothelial cells SV-HUC1. Our results show that CBD treatment of urothelial cells significantly decreased TNFα-upregulated mRNA and protein expression of IL1α, IL8, CXCL1, and CXCL10, as well as attenuated NFκB phosphorylation. In addition, CBD treatment also diminished TNFα-driven cellular reactive oxygen species generation (ROS), by increasing the expression of the redox-sensitive transcription factor Nrf2, the antioxidant enzymes superoxide dismutase 1 and 2, and hem oxygenase 1. CBD-mediated effects in urothelial cells may occur by the activation of the PPARγ receptor since inhibition of PPARγ resulted in significantly diminished anti-inflammatory and antioxidant effects of CBD. Our observations provide new insights into the therapeutic potential of CBD through modulation of PPARγ/Nrf2/NFκB signaling pathways, which could be further exploited in the treatment of IC/BPS.


Assuntos
Canabidiol , Cistite Intersticial , Humanos , Antioxidantes/farmacologia , Canabidiol/farmacologia , Inflamação , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo , PPAR gama/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
5.
Methods Mol Biol ; 2566: 99-110, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36152245

RESUMO

The function of glycoproteins depends both on their polypeptide chain and sugar residues. For detection and localization of glycoproteins in tissue sections, methods of immunohistochemistry (IHC) and lectin histochemistry (LHC) are usually used separately. For a better understanding of the expression and distribution of variants of glycoproteins, tissue sections can be analyzed by combined lectin- and immuno-histochemistry (CLIH). CLIH exploits the advantages of both IHC and LHC and can therefore contribute to research in glycobiology and other fields of cell biology. Since cancer transformation is accompanied by alterations in the glycosylation of some glycoproteins, CLIH could also be exploited for improved classification of cancers. The chapter considers how CLIH could be employed on paraffin sections and semithin cryosections for fluorescence microscopy. Five different protocols of CLIH are described in detail as well as appropriate negative controls.


Assuntos
Lectinas , Neoplasias , Glicoproteínas , Histocitoquímica/métodos , Humanos , Imuno-Histoquímica , Lectinas/metabolismo , Microscopia de Fluorescência , Parafina , Açúcares
6.
J Vis Exp ; (187)2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-36190234

RESUMO

Extracellular vesicles (EVs) are membrane-limited structures released from the cells into the extracellular space and are implicated in intercellular communication. EVs consist of three populations of vesicles, namely microvesicles (MVs), exosomes, and apoptotic bodies. The limiting membrane of EVs is crucially involved in the interactions with the recipient cells, which could lead to the transfer of biologically active molecules to the recipient cells and, consequently, affect their behavior. The freeze-fracture electron microscopy technique is used to study the internal organization of biological membranes. Here, we present a protocol for MV isolation from cultured cancerous urothelial cells and the freeze-fracture of MVs in the steps of rapid freezing, fracturing, making and cleaning the replicas, and analyzing them with transmission electron microscopy. The results show that the protocol for isolation yields a homogenous population of EVs, which correspond to the shape and size of MVs. Intramembrane particles are found mainly in the protoplasmic face of the limiting membrane. Hence, freeze-fracture is the technique of choice to characterize the MVs' diameter, shape, and distribution of membrane proteins. The presented protocol is applicable to other populations of EVs.


Assuntos
Exossomos , Vesículas Extracelulares , Exossomos/metabolismo , Vesículas Extracelulares/metabolismo , Técnica de Fratura por Congelamento , Proteínas de Membrana/metabolismo , Microscopia Eletrônica
7.
Comput Methods Programs Biomed ; 223: 106959, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35763876

RESUMO

BACKGROUND AND OBJECTIVES: In recent years, electron microscopy is enabling the acquisition of volumetric data with resolving power to directly observe the ultrastructure of intracellular compartments. New insights and knowledge about cell processes that are offered by such data require a comprehensive analysis which is limited by the time-consuming manual segmentation and reconstruction methods. METHOD: We present methods for automatic segmentation, reconstruction, and analysis of intracellular compartments from volumetric data obtained by the dual-beam electron microscopy. We specifically address segmentation of fusiform vesicles and the Golgi apparatus, reconstruction of mitochondria and fusiform vesicles, and morphological analysis of the reconstructed mitochondria. RESULTS AND CONCLUSION: Evaluation on the public UroCell dataset demonstrated high accuracy of the proposed methods for segmentation of fusiform vesicles and the Golgi apparatus, as well as for reconstruction of mitochondria and analysis of their shapes, while reconstruction of fusiform vesicles proved to be more challenging. We published an extension of the UroCell dataset with all of the data used in this work, to further contribute to research on automatic analysis of the ultrastructure of intracellular compartments.


Assuntos
Processamento de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador/métodos , Microscopia Eletrônica
8.
Int J Mol Sci ; 22(12)2021 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-34199232

RESUMO

Non-muscle-invasive bladder cancer is the most common form of bladder cancer. The main problem in managing bladder tumors is the high recurrence after the transurethral resection of bladder tumors (TURBT). Our study aimed to examine the fate of intravesically applied cancer cells as the implantation of cancer cells after TURBT is thought to be a cause of tumor recurrence. We established an orthotopic mouse bladder tumor model with MB49-GFP cancer cells and traced them during the first three days to define their location and contacts with normal urothelial cells. Data were obtained by Western blot, immunolabeling, and light and electron microscopy. We showed that within the first two hours, applied cancer cells adhered to the traumatized epithelium by cell projections containing α3ß1 integrin on their tips. Cancer cells then migrated through the epithelium and on day 3, they reached the basal lamina or even penetrated it. In established bladder tumors, E-cadherin and desmoplakin 1/2 were shown as feasible immunohistochemical markers of tumor margins based on the immunolabeling of various junctional proteins. Altogether, these results for the first time illustrate cancer cell implantation in vivo mimicking cellular events of tumor recurrence in bladder cancer patients.


Assuntos
Epitélio/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias da Bexiga Urinária/patologia , Bexiga Urinária/patologia , Animais , Caderinas/metabolismo , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Modelos Animais de Doenças , Feminino , Integrina alfa3beta1/metabolismo , Junções Intercelulares/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos Endogâmicos C57BL , Invasividade Neoplásica , Bexiga Urinária/ultraestrutura , Neoplasias da Bexiga Urinária/ultraestrutura , Urotélio/patologia , Urotélio/ultraestrutura
9.
Int J Mol Sci ; 22(7)2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33805295

RESUMO

Bladder cancer (BC) is the tenth most common cancer worldwide with a high recurrence rate, morbidity and mortality. Therefore, chemoprevention and improved treatment of BC are of paramount importance. Epidemiological studies suggest that adequate vitamin A intake may be associated with reduced BC risk. In addition, retinoids, natural and synthetic derivatives of vitamin A, are intensively studied in cancer research due to their antioxidant properties and their ability to regulate cell growth, differentiation, and apoptosis. Findings from in vivo and in vitro models of BC show great potential for the use of retinoids in the chemoprevention and treatment of BC. However, translation to the clinical practice is limited. In this narrative review we discuss: (i) vitamin A and retinoid metabolism and retinoic acid signalling, (ii) the pathobiology of BC and the need for chemoprevention, (iii) the epidemiological evidence for the role of dietary vitamin A in BC, (iv) mechanistic insights obtained from in vivo and in vitro models, (v) clinical trials of retinoids and the limitations of retinoid use, (vi) novel systems of retinoid delivery, and (vii) components of retinoid signalling pathways as potential novel therapeutic targets.


Assuntos
Anticarcinógenos/uso terapêutico , Antineoplásicos/uso terapêutico , Retinoides/metabolismo , Neoplasias da Bexiga Urinária/tratamento farmacológico , Vitamina A/metabolismo , Animais , Apoptose , Diferenciação Celular , Humanos , Retinoides/farmacologia , Retinoides/uso terapêutico , Transdução de Sinais , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/fisiopatologia , Neoplasias da Bexiga Urinária/prevenção & controle , Vitamina A/farmacologia , Vitamina A/uso terapêutico
10.
Eur J Histochem ; 65(2)2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33764020

RESUMO

The urothelium, an epithelium of the urinary bladder, primarily functions as blood-urine permeability barrier. The urothelium has a very slow turn-over under normal conditions but is capable of extremely fast response to injury. During regeneration urothelium either restores normal function or undergoes altered differentiation pathways, the latter being the cause of several bladder diseases. In this review, we describe the structure of the apical plasma membrane that enables barrier function, the role of urothelium specific proteins uroplakins and the machinery for polarized membrane transports in terminally differentiated superficial umbrella cells. We address key markers, such as keratins, cancer stem cell markers, retinoic acid signalling pathway proteins and transient receptor potential channels and purinergic receptors that drive normal and altered differentiation in bladder cancer and bladder pain syndrome. Finally, we discuss uncertainties regarding research, diagnosis and treatment of bladder pain syndrome. Throughout the review, we emphasise the contribution of immunohistochemistry in advancing our understanding of processes in normal and diseased bladder as well as the most promising possibilities for improved bladder cancer and bladder pain syndrome management.


Assuntos
Cistite Intersticial/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Bexiga Urinária/metabolismo , Urotélio/metabolismo , Animais , Humanos , Imuno-Histoquímica , Receptores Purinérgicos P2X/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/patologia , Uroplaquinas/metabolismo
11.
Int J Mol Sci ; 21(22)2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33187334

RESUMO

Glioblastoma (GBM), the most common primary brain tumor, is a complex and extremely aggressive disease. Despite recent advances in molecular biology, there is a lack of biomarkers, which would improve GBM's diagnosis, prognosis, and therapy. Here, we analyzed by qPCR the expression levels of a set of miRNAs in GBM and lower-grade glioma human tissue samples and performed a survival analysis in silico. We then determined the expression of same miRNAs and their selected target mRNAs in small extracellular vesicles (sEVs) of GBM cell lines. We showed that the expression of miR-21-5p was significantly increased in GBM tissue compared to lower-grade glioma and reference brain tissue, while miR-124-3p and miR-138-5p were overexpressed in reference brain tissue compared to GBM. We also demonstrated that miR-9-5p and miR-124-3p were overexpressed in the sEVs of GBM stem cell lines (NCH421k or NCH644, respectively) compared to the sEVs of all other GBM cell lines and astrocytes. VIM mRNA, a target of miR-124-3p and miR-138-5p, was overexpressed in the sEVs of U251 and U87 GBM cell lines compared to the sEVs of GBM stem cell line and also astrocytes. Our results suggest VIM mRNA, miR-9-5p miRNA, and miR-124-3p miRNA could serve as biomarkers of the sEVs of GBM cells.


Assuntos
Neoplasias Encefálicas/genética , Vesículas Extracelulares/genética , Glioblastoma/genética , MicroRNAs/genética , Astrócitos/patologia , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Vesículas Extracelulares/patologia , Regulação Neoplásica da Expressão Gênica/genética , Glioblastoma/patologia , Humanos , Prognóstico , RNA Mensageiro/genética
12.
Eur J Histochem ; 64(3)2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32613817

RESUMO

Lectin histochemistry (LHC) and immunohistochemistry (IHC), which demonstrate the composition and localisation of sugar residues and proteins in cell membranes, respectively, are generally used separately. Using these two methods, we previously demonstrated that malignant transformation of urothelial cells results in the alterations of protein glycosylation and reduced expression of urothelium-specific integral membrane proteins uroplakins (UPs). However, the correlation between these changes was not studied yet. To evaluate this correlation, we developed innovative method, which we named combined lectin- and immuno- histochemistry (CLIH). We used human biopsies of 6 normal urothelia and 9 papillary urothelial carcinomas, i.e. 3 papillary urothelial neoplasms of low malignant potential (PUNLMP), 3 non-invasive papillary urothelial carcinomas of low grade (pTa, l.g.), and 3 invasive papillary urothelial carcinomas of high grade (pT1, h.g.). We tested five different protocols (numbered 1-5) of CLIH on paraffin and cryo-semithin sections and compared them with LHC and IHC performed separately. Additionally, we carried out western and lectin blotting with antibodies against UPs and lectins Amaranthus caudatus agglutinin (ACA), Datura stramonium agglutinin (DSA), and jacalin, respectively. We showed that incubation with primary antibodies first, followed by the mixture of secondary antibodies and lectins is the most efficient CLIH method (protocol number 5). Additionally, 300 nm thick cryo-semithin sections enabled better resolution of co-localisation between sugar residues and proteins than 5 µm thick paraffin sections. In the normal urothelium, CLIH showed co-localisation of lectins ACA and jacalin with UPs in the apical plasma membrane (PM) of superficial umbrella cells. In papillary urothelial carcinomas, all three lectins (ACA, DSA and jacalin) labelled regions of apical PM, where they occasionally co-localised with UPs. Western and lectin blotting confirmed the differences between normal urothelium and papillary urothelial carcinomas. Our results show that CLIH, when used with various sets of lectins and antigens, is a useful, quick, and reliable method that could be applied for basic cell biology research as well as detailed subtyping of human urothelial carcinomas.


Assuntos
Carcinoma Papilar/diagnóstico por imagem , Células Epiteliais/metabolismo , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Aglutininas/metabolismo , Amaranthus/química , Animais , Anticorpos/imunologia , Artocarpus/química , Bovinos , Datura stramonium/química , Corantes Fluorescentes/química , Cabras , Humanos , Imuno-Histoquímica , Microscopia de Fluorescência , Lectinas de Plantas/metabolismo , Coelhos , Rodaminas/química , Ácidos Sulfônicos/química , Bexiga Urinária/patologia , Uroplaquinas/imunologia , Uroplaquinas/metabolismo , Urotélio/metabolismo , Urotélio/patologia
13.
Cancers (Basel) ; 12(7)2020 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-32605249

RESUMO

Urinary bladder cancer is one of the leading malignancies worldwide, with the highest recurrence rates. A diet rich in vitamin A has proven to lower the risk of cancer, yet the molecular mechanisms underlying this effect are unknown. We found that vitamin A decreased urothelial atypia and apoptosis during early bladder carcinogenesis induced by N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN). Vitamin A did not alter urothelial cell desquamation, differentiation, or proliferation rate. Genes like Wnt5a, involved in retinoic acid signaling, and transcription factors Pparg, Ppara, Rxra, and Hoxa5 were downregulated, while Sox9 and Stra6 were upregulated in early urothelial carcinogenesis. When a vitamin A rich diet was provided during BBN treatment, none of these genes was up- or downregulated; only Lrat and Neurod1 were upregulated. The lecithin retinol acyltransferase (LRAT) enzyme that produces all-trans retinyl esters was translocated from the cytoplasm to the nuclei in urothelial cells as a consequence of BBN treatment regardless of vitamin A rich diet. A vitamin A-rich diet altered retinoic acid signaling, decreased atypia and apoptosis of urothelial cells, and consequently diminished early urothelial carcinogenesis.

14.
Comput Biol Med ; 119: 103693, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32339123

RESUMO

Automatic segmentation of intracellular compartments is a powerful technique, which provides quantitative data about presence, spatial distribution, structure and consequently the function of cells. With the recent development of high throughput volumetric data acquisition techniques in electron microscopy (EM), manual segmentation is becoming a major bottleneck of the process. To aid the cell research, we propose a technique for automatic segmentation of mitochondria and endolysosomes obtained from urinary bladder urothelial cells by the dual beam EM technique. We present a novel publicly available volumetric EM dataset - the first of urothelial cells, evaluate several state-of-the-art segmentation methods on the new dataset and present a novel segmentation pipeline, which is based on supervised deep learning and includes mechanisms that reduce the impact of dependencies in the input data, artefacts and annotation errors. We show that our approach outperforms the compared methods on the proposed dataset.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador , Artefatos , Microscopia Eletrônica , Mitocôndrias
15.
Bioelectrochemistry ; 132: 107440, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31869699

RESUMO

Pulsed electric fields (PEFs) can be used to transiently increase cell membrane permeability in procedures ranging from gene therapy to tumor eradication. Although very efficient, PEF-based therapies generally require the use of invasive electrodes, which cause pain and tissue damage. An emerging noninvasive, contactless alternative to PEFs are High Intensity Pulsed Electromagnetic Fields (HI-PEMF), whereby the electric field inside the tissue is induced remotely by external pulsed magnetic field. However, one of the current major drawbacks of HI-PEMFs is their inferior efficiency compared to PEFs. In this study we present the proof-of-concept that by adding highly conductive 5 and 20 nm gold nanoparticles (Au NPs), we can significantly potentiate the permeabilizing effect of HI-PEMFs, making it possible to permeabilize up to 80% of the cells with minimal or no effect on cell survival, compared to negligible percentage of permeabilized cells using HI-PEMF alone. Experiments, conducted on Chinese Hamster Ovary cells and Escherichia coli, suggest that Au NPs act as distributed nanoelectrodes, locally enhancing the electric field induced at the plasma membrane. Our findings open up an avenue of possibilities for combining naked as well as functionalized Au NPs with HI-PEMFs for noninvasive, remotely controlled smart drug delivery applications.


Assuntos
Eletrodos , Campos Eletromagnéticos , Eletroporação/métodos , Nanotecnologia , Animais , Células CHO , Cricetulus , Bactérias Gram-Negativas/metabolismo
16.
Mol Biol Cell ; 30(24): 2969-2984, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31577526

RESUMO

The apical surface of the terminally differentiated mammalian urothelial umbrella cell is mechanically stable and highly impermeable, in part due to its coverage by urothelial plaques consisting of 2D crystals of uroplakin particles. The mechanism for regulating the uroplakin/plaque level is unclear. We found that genetic ablation of the highly tissue-specific sorting nexin Snx31, which localizes to plaques lining the multivesicular bodies (MVBs) in urothelial umbrella cells, abolishes MVBs suggesting that Snx31 plays a role in stabilizing the MVB-associated plaques by allowing them to achieve a greater curvature. Strikingly, Snx31 ablation also induces a massive accumulation of uroplakin-containing mitochondria-derived lipid droplets (LDs), which mediate uroplakin degradation via autophagy/lipophagy, leading to the loss of apical and fusiform vesicle plaques. These results suggest that MVBs play an active role in suppressing the excessive/wasteful endocytic degradation of uroplakins. Failure of this suppression mechanism triggers the formation of mitochondrial LDs so that excessive uroplakin membranes can be sequestered and degraded. Because mitochondrial LD formation, which occurs at a low level in normal urothelium, can also be induced by disturbance in uroplakin polymerization due to individual uroplakin knockout and by arsenite, a bladder carcinogen, this pathway may represent an inducible, versatile urothelial detoxification mechanism.


Assuntos
Corpos Multivesiculares/metabolismo , Nexinas de Classificação/metabolismo , Urotélio/metabolismo , Animais , Feminino , Gotículas Lipídicas/metabolismo , Gotículas Lipídicas/fisiologia , Glicoproteínas de Membrana/metabolismo , Membranas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Bexiga Urinária/metabolismo , Uroplaquinas/metabolismo , Uroplaquinas/fisiologia
17.
Histochem Cell Biol ; 152(3): 195-206, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31179519

RESUMO

Desmosomal cadherins, desmocollins, and desmogleins are cholesterol-dependent entities responsible for the stable adhesion of desmosomes in epithelial cells. Here, we investigated the influence of cellular cholesterol depletion on the dynamic properties of the desmosomal cadherin desmocollin, particularly the lateral mobility and distribution of desmocollin 2 (Dsc2-YFP) in the plasma membrane, and how these properties influence the adhesion strength of desmosomes. Depletion of cellular cholesterol decreased the lateral mobility of Dsc2-YFP and caused dispersion of Dsc2-YFP in the plasma membrane of epithelial MDCK cells. As a consequence of the altered Dsc2-YFP dynamics, the adhesive strength of desmosomes was weakened. Moreover, our study is the first to show and quantify the co-association of desmosomes with cholesterol/sphingomyelin-enriched membrane domains at the ultrastructural level. Taken together, our data emphasize a critical role for the cellular cholesterol content in regulating the lateral mobility and distribution of Dsc2 and show that cholesterol depletion reduces the strength of desmosomal adhesions.


Assuntos
Colesterol/metabolismo , Caderinas de Desmossomos/metabolismo , Desmossomos/metabolismo , Animais , Membrana Celular/química , Membrana Celular/metabolismo , Células Cultivadas , Colesterol/deficiência , Cães , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Células Madin Darby de Rim Canino
18.
Glycobiology ; 29(5): 355-365, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30689891

RESUMO

Urinary bladder cancer is the ninth most common cancer in developed countries with poor prognosis and outcome for the patient due to the challenging diagnosis and limited treatment possibilities. Bladder cancer arises mainly from urothelial cells lining the lumen. Urothelial cells form a three- to five-layered urothelium, which maintains the blood-urine barrier. The carbohydrates that cover the apical surface of superficial urothelial cells, i.e. umbrella cells, are crucial for this function. The composition of the carbohydrate covering is altered during urothelial cancer transformation. These bladder cancer-associated carbohydrate changes are a promising field for diagnosis, therapy and management. Lectins, which are carbohydrate-binding proteins, can be used to detect subtle alterations in carbohydrate composition during urothelial cancer transformation. Extensive research into various lectin applications has already been conducted, but the results are often contradictory and confusing. None of these applications have reached clinical trials. We review the literature and discuss (i) current bladder cancer management, (ii) lectin-based assays for detection of various cancer subtypes, (iii) lectin-based strategies for innovative bladder cancer treatment and finally (iv) lectins in nanotheranostics for personalized bladder cancer management.


Assuntos
Lectinas/análise , Lectinas/metabolismo , Nanomedicina Teranóstica , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Animais , Humanos , Neoplasias da Bexiga Urinária/metabolismo
19.
ACS Synth Biol ; 7(12): 2715-2725, 2018 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-30513193

RESUMO

The CRISPR/Cas system has been developed as a potent tool for genome engineering and transcription regulation. However, the efficiency of the delivery of the system into cells, particularly for therapeutic in vivo applications, remains a major bottleneck. Extracellular vesicles (EVs), released by eukaryotic cells, can mediate the transfer of various molecules, including nucleic acids and proteins. We show the packaging and delivery of the CRISPR/Cas system via EVs to the target cells, combining the advantages of both technological platforms. A genome editing with designed extracellular vesicles (GEDEX) system generated by the producer cells can transfer the designed transcriptional regulator dCas9-VPR complexed with appropriate targeting gRNAs enabling activation of gene transcription. We show functional delivery in mammalian cells as well in the animals. The therapeutic efficiency of in vivo delivery of dCas9-VPR/sgRNA GEDEX is demonstrated in a mouse model of liver damage counteracted by upregulation of the endogenous hepatocyte growth factor, demonstrating the potential for therapeutic applications.


Assuntos
Sistemas CRISPR-Cas/genética , Vesículas Extracelulares/metabolismo , Edição de Genes/métodos , Animais , Linhagem Celular , Doença Hepática Induzida por Substâncias e Drogas/patologia , Doença Hepática Induzida por Substâncias e Drogas/terapia , Modelos Animais de Doenças , Vesículas Extracelulares/genética , Vesículas Extracelulares/transplante , Regulação da Expressão Gênica , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Fator de Crescimento de Hepatócito/genética , Humanos , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Endogâmicos BALB C , Plasmídeos/genética , Plasmídeos/metabolismo
20.
Blood ; 131(15): 1720-1729, 2018 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-29358175

RESUMO

The link between inflammation and cancer is particularly strong in Waldenström macroglobulinemia (WM), a diffuse large B-cell lymphoma wherein the majority of patients harbor a constitutively active mutation in the innate immune-signaling adaptor myeloid differentiation primary response 88 (MyD88). MyD88Leu265Pro (MyD88L265P) constitutively triggers the myddosome assembly providing a survival signal for cancer cells. Here, we report detection and a functional role of MyD88 in the extracellular vesicles (EVs) shed from WM cells. MyD88L265P was transferred via EVs into the cytoplasm of the recipient mast cells and macrophages, recruiting the endogenous MyD88 that triggered the activation of proinflammatory signaling in the absence of receptor activation. Additionally, internalization of EVs containing MyD88L265P was observed in mice with an effect on the bone marrow microenvironment. MyD88-loaded EVs were detected in the bone marrow aspirates of WM patients thus establishing the physiological role of EVs for MyD88L265P transmission and shaping of the proinflammatory microenvironment. Results establish the mechanism of transmission of signaling complexes via EVs to propagate inflammation as a new mechanism of intercellular communication.


Assuntos
Medula Óssea/metabolismo , Comunicação Celular , Vesículas Extracelulares/metabolismo , Mutação de Sentido Incorreto , Fator 88 de Diferenciação Mieloide/metabolismo , Transdução de Sinais , Macroglobulinemia de Waldenstrom/metabolismo , Substituição de Aminoácidos , Animais , Medula Óssea/patologia , Vesículas Extracelulares/genética , Vesículas Extracelulares/patologia , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Fator 88 de Diferenciação Mieloide/genética , Macroglobulinemia de Waldenstrom/genética , Macroglobulinemia de Waldenstrom/patologia
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