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1.
PLoS One ; 15(8): e0237976, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32822399

RESUMO

Environmental exposure to arsenite (As3+) has a strong association with the development of human urothelial cancer (UC) and is the 5th most common cancer in men and the 12th most common cancer in women. Muscle invasive urothelial cancer (MIUC) are grouped into basal or luminal molecular subtypes based on their gene expression profile. The basal subtype is more aggressive and can be associated with squamous differentiation, characterized by high expression of keratins (KRT1, 5, 6, 14, and 16) and epidermal growth factor receptor (EGFR) within the tumors. The luminal subtype is less aggressive and is predominately characterized by elevated gene expression of peroxisome proliferator-activated receptor- gamma (PPARγ) and forkhead box protein A1 (FOXA1). We have previously shown that As3+-transformed urothelial cells (As-T) exhibit a basal subtype of UC expressing genes associated with squamous differentiation. We hypothesized that the molecular subtype of the As-T cells could be altered by inducing the expression of PPARγ and/or inhibiting the proliferation of the cells. Non-transformed and As-T cells were treated with Troglitazone (TG, PPARG agonist, 10 µM), PD153035 (PD, an EGFR inhibitor, 1 µM) or a combination of TG and PD for 3 days. The results obtained demonstrate that treatment of the As-T cells with TG upregulated the expression of PPARγ and FOXA1 whereas treatment with PD decreased the expression of some of the basal keratins. However, a combined treatment of TG and PD resulted in a consistent decrease of several proteins associated with the basal subtype of bladder cancers (KRT1, KRT14, KRT16, P63, and TFAP2A). Our data suggests that activation of PPARγ while inhibiting cell proliferation facilitates the regulation of genes involved in maintaining the luminal subtype of UC. In vivo animal studies are needed to address the efficacy of using PPARγ agonists and/or proliferation inhibitors to reduce tumor grade/stage of MIUC.


Assuntos
Arsenitos/farmacologia , Proliferação de Células/efeitos dos fármacos , PPAR gama/metabolismo , Troglitazona/farmacologia , Animais , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Fator 3-alfa Nuclear de Hepatócito/genética , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Humanos , Queratinas/genética , Queratinas/metabolismo , Camundongos , Camundongos Nus , PPAR gama/agonistas , Quinazolinas/farmacologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma/efeitos dos fármacos , Transplante Heterólogo , Regulação para Cima/efeitos dos fármacos , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia
2.
Nature ; 585(7825): 404-409, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32848249

RESUMO

To implant in the uterus, the mammalian embryo first specifies two cell lineages: the pluripotent inner cell mass that forms the fetus, and the outer trophectoderm layer that forms the placenta1. In many organisms, asymmetrically inherited fate determinants drive lineage specification2, but this is not thought to be the case during early mammalian development. Here we show that intermediate filaments assembled by keratins function as asymmetrically inherited fate determinants in the mammalian embryo. Unlike F-actin or microtubules, keratins are the first major components of the cytoskeleton that display prominent cell-to-cell variability, triggered by heterogeneities in the BAF chromatin-remodelling complex. Live-embryo imaging shows that keratins become asymmetrically inherited by outer daughter cells during cell division, where they stabilize the cortex to promote apical polarization and YAP-dependent expression of CDX2, thereby specifying the first trophectoderm cells of the embryo. Together, our data reveal a mechanism by which cell-to-cell heterogeneities that appear before the segregation of the trophectoderm and the inner cell mass influence lineage fate, via differential keratin regulation, and identify an early function for intermediate filaments in development.


Assuntos
Linhagem da Célula , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Queratinas/metabolismo , Actinas/metabolismo , Animais , Divisão Celular , Montagem e Desmontagem da Cromatina , Proteínas Cromossômicas não Histona/metabolismo , Ectoderma/citologia , Embrião de Mamíferos/embriologia , Feminino , Humanos , Filamentos Intermediários/metabolismo , Camundongos , Microtúbulos/metabolismo , Complexos Multiproteicos/metabolismo , Trofoblastos/citologia
3.
Clin Sci (Lond) ; 134(7): 907-920, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32236445

RESUMO

BACKGROUND: Increased keratinocyte proliferation occurs in the skin of psoriatic patients and is supposed to play a role in the pathogenesis of this disorder. Compounds interfering with keratinocyte proliferation could be useful in the management of psoriatic patients. AIM: To investigate whether albendazole, an anti-helmintic drug that regulates epithelial cell function in various systems, inhibits keratinocyte proliferation in models of psoriasis. METHODS: Aldara-treated mice received daily topical application of albendazole. Keratinocyte proliferation and keratin (K) 6 and K16 expression were evaluated by immunohistochemistry and Western blotting and inflammatory cells/mediators were analysed by immunohistochemistry and real-time PCR. In human keratinocytes (HEKa and HaCaT) treated with albendazole, cell cycle and proliferation, keratins and cell cycle-associated factors were evaluated by flow cytometry, colorimetric assay and Western blotting respectively. RESULTS: Aldara-treated mice given albendazole exhibited reduced epidermal thickness, decreased number of proliferating keratinocytes and K6/K16 expression. Reduction of CD3- and Ly6G-positive cells in the skin of albendazole-treated mice associated with inhibition of IL-6, TNF-α, IL-1ß, IL-17A, IL-36, CCL17, CXCL1, CXCL2 and CXCL5 expression. Treatment of keratinocytes with albendazole reduced K6/K16 expression and reversibly inhibited cell growth by promoting accumulation of cells in S-phase. This phenomenon was accompanied by down-regulation of CDC25A, a phosphatase regulating progression of cell cycle through S-phase, and PKR-dependent hyper-phosphorylation of eIF2α, an inhibitor of CDC25 translation. In Aldara-treated mice, albendazole activated PKR, enhanced eIF2α phosphorylation and reduced CDC25A expression. CONCLUSIONS: Data show that albendazole inhibits keratinocyte proliferation and exerts therapeutic effect in a murine model of psoriasis.


Assuntos
Albendazol/farmacologia , Proliferação de Células/efeitos dos fármacos , Fármacos Dermatológicos/farmacologia , Queratinócitos/efeitos dos fármacos , Psoríase/tratamento farmacológico , Pele/efeitos dos fármacos , Animais , Linhagem Celular , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Fator de Iniciação 2 em Eucariotos/metabolismo , Humanos , Imiquimode , Mediadores da Inflamação/metabolismo , Queratinócitos/metabolismo , Queratinócitos/patologia , Queratinas/genética , Queratinas/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Fosforilação , Psoríase/induzido quimicamente , Psoríase/metabolismo , Psoríase/patologia , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Transdução de Sinais , Pele/metabolismo , Pele/patologia , Fosfatases cdc25/metabolismo , eIF-2 Quinase/metabolismo
4.
World Neurosurg ; 139: 60-62, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32298826

RESUMO

BACKGROUND: We describe a cytokeratin positive interstitial reticulum cell tumor (CPIRCT) as the cause of a large and defacing scalp tumor. Clinically these tumors manifest as progressive, painless swelling. Treatment usually consists of surgery with or without irradiation; chemotherapy is applied in metastatic disease. CASE DESCRIPTION: A patient was referred after attempted removal of a large bump on the head. The tumor was initially noted about 12 months earlier. Assuming a benign lipoma, resection without prior imaging was attempted. During surgery, the underlying bone was found to be profoundly destroyed. Cranial magnetic resonance imaging revealed a large mass with an extracranial and intracranial component. Subsequent extensive resection finally led to the diagnosis of CPIRCT. CONCLUSIONS: Most CPIRCTs manifest as progressive palpable or visible masses. Radical excision is usually the mainstay of treatment, although there is no generally accepted treatment strategy. A needle biopsy might not be diagnostic and can complicate future curative surgery. Especially in fast-growing lesions, imaging studies should be considered before surgery. Their potential recurrence and metastatic spread render CPIRCTs an interdisciplinary challenge and highlight the need for long-term follow-up.


Assuntos
Neoplasias Encefálicas/patologia , Queratinas/metabolismo , Neoplasias Cranianas/patologia , Adulto , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/cirurgia , Erros de Diagnóstico , Neoplasias de Cabeça e Pescoço/diagnóstico , Humanos , Lipoma/diagnóstico , Imagem por Ressonância Magnética , Masculino , Couro Cabeludo , Neoplasias Cranianas/diagnóstico por imagem , Neoplasias Cranianas/metabolismo , Neoplasias Cranianas/cirurgia
5.
Eur J Histochem ; 64(2)2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32312032

RESUMO

Interleukin 17A (IL-17A), mainly produced by the T helper subclass Th17, plays a key role in the psoriatic plaque formation and progression. The clinical effectiveness of anti-IL-17A agents is documented, but the early and specific mechanisms of their protection are not identified yet. The challenge of the present study is to investigate the possible reversal exerted by a specific anti-IL-17A agent on the psoriatic events induced by IL-17A in a three-dimensional organotypic model of normal human skin. Bioptic skin fragments obtained after aesthetic surgery of healthy women (n=5) were incubated with i) IL-17A biological inhibitor (anti-IL-17A), ii) IL-17A, iii) a combination of IL-17A and its specific IL-17A biological inhibitor (COMBO). A Control group was in parallel cultured and incubation lasted for 24 and 48 h epidermal-side-up at the air-liquid interface. All subjects were represented in all experimental groups at all considered time-points. Keratinocyte proliferation and the presence of epidermal Langerhans cells were quantitatively estimated. In parallel with transmission electron microscopy analysis, immunofluorescence studies for the epidermal distribution of keratin (K)10, K14, K16, K17, filaggrin/occludin, Toll-like Receptor 4, and Nuclear Factor kB were performed. IL-17A inhibited cell proliferation and induced K17 expression, while samples incubated with the anti-IL-17A agent were comparable to controls. In the COMBO group the IL-17A-induced effects were almost completely reverted. Our study, for the first time, elucidates the most specific psoriatic cellular events that can be partially affected or completely reverted by a specific anti-IL-17A agent during the early phases of the plaque onset and progression. On the whole, this work contributes to expand the knowledge of the psoriatic tableau.


Assuntos
Anticorpos Monoclonais/farmacologia , Interleucina-17/antagonistas & inibidores , Psoríase/metabolismo , Pele/metabolismo , Adulto , Anticorpos Monoclonais/imunologia , Feminino , Humanos , Interleucina-17/imunologia , Interleucina-17/farmacologia , Queratinas/metabolismo , Células de Langerhans/metabolismo , Subunidade p50 de NF-kappa B/metabolismo , Ocludina/metabolismo , Psoríase/patologia , Proteínas S100/metabolismo , Pele/ultraestrutura , Receptor 4 Toll-Like/metabolismo , Adulto Jovem
6.
Science ; 367(6483)2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-32165560

RESUMO

At the body surface, skin's stratified squamous epithelium is challenged by environmental extremes. The surface of the skin is composed of enucleated, flattened surface squames. They derive from underlying, transcriptionally active keratinocytes that display filaggrin-containing keratohyalin granules (KGs) whose function is unclear. Here, we found that filaggrin assembles KGs through liquid-liquid phase separation. The dynamics of phase separation governed terminal differentiation and were disrupted by human skin barrier disease-associated mutations. We used fluorescent sensors to investigate endogenous phase behavior in mice. Phase transitions during epidermal stratification crowded cellular spaces with liquid-like KGs whose coalescence was restricted by keratin filament bundles. We imaged cells as they neared the skin surface and found that environmentally regulated KG phase dynamics drive squame formation. Thus, epidermal structure and function are driven by phase-separation dynamics.


Assuntos
Epiderme/fisiologia , Transição de Fase , Animais , Citoplasma/metabolismo , Humanos , Proteínas de Filamentos Intermediários/genética , Proteínas de Filamentos Intermediários/metabolismo , Queratinócitos/metabolismo , Queratinócitos/fisiologia , Queratinas/metabolismo , Camundongos
7.
PLoS One ; 15(1): e0228108, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32004342

RESUMO

Although organic matter may accumulate sometimes (e.g. lignocellulose in peat bog), most natural biodegradation processes are completed until full mineralization. Such transformations are often achieved by the concerted action of communities of interacting microbes, involving different species each performing specific tasks. These interactions can give rise to novel "community-intrinsic" properties, through e.g. activation of so-called "silent genetic pathways" or synergistic interplay between microbial activities and functions. Here we studied the microbial community-based degradation of keratin, a recalcitrant biological material, by four soil isolates, which have previously been shown to display synergistic interactions during biofilm formation; Stenotrophomonas rhizophila, Xanthomonas retroflexus, Microbacterium oxydans and Paenibacillus amylolyticus. We observed enhanced keratin weight loss in cultures with X. retroflexus, both in dual and four-species co-cultures, as compared to expected keratin degradation by X. retroflexus alone. Additional community intrinsic properties included accelerated keratin degradation rates and increased biofilm formation on keratin particles. Comparison of secretome profiles of X. retroflexus mono-cultures to co-cultures revealed that certain proteases (e.g. serine protease S08) were significantly more abundant in mono-cultures, whereas co-cultures had an increased abundance of proteins related to maintaining the redox environment, e.g. glutathione peroxidase. Hence, one of the mechanisms related to the community intrinsic properties, leading to enhanced degradation from co-cultures, might be related to a switch from sulfitolytic to proteolytic functions between mono- and co-cultures, respectively.


Assuntos
Bactérias/metabolismo , Queratinas/metabolismo , Consórcios Microbianos/fisiologia , Biodegradação Ambiental , Biofilmes , Técnicas de Cocultura , Interações Microbianas , Microbiologia do Solo
8.
Cells ; 9(2)2020 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-31991791

RESUMO

: During chronic liver injury, hepatic stellate cells (HSC) undergo activation and are the principal cellular source of collagenous scar. In this study, we found that activation of mouse HSC (mHSC) was associated with a 4.5-fold increase in extracellular vesicle (EV) production and that fibrogenic gene expression (CCN2, Col1a1) was suppressed in Passage 1 (P1; activated) mHSC exposed to EVs from Day 4 (D4; relatively quiescent) mHSC but not to EVs from P1 mHSC. Conversely, gene expression (CCN2, Col1a1, αSMA) in D4 mHSC was stimulated by EVs from P1 mHSC but not by EVs from D4 mHSC. EVs from Day 4 mHSC contained only 46 proteins in which histones and keratins predominated, while EVs from P1 mHSC contained 337 proteins and these were principally associated with extracellular spaces or matrix, proteasome, collagens, vesicular transport, metabolic enzymes, ribosomes and chaperones. EVs from the activated LX-2 human HSC (hHSC) line also promoted fibrogenic gene expression in D4 mHSC in vitro and contained 524 proteins, many of which shared identity or had functional overlap with those in P1 mHSC EVs. The activation-associated changes in production, function and protein content of EVs from HSC likely contribute to the regulation of HSC function in vivo and to the fine-tuning of fibrogenic pathways in the liver.


Assuntos
Vesículas Extracelulares/metabolismo , Regulação da Expressão Gênica/genética , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/metabolismo , Proteoma/metabolismo , Transdução de Sinais/genética , Animais , Linhagem Celular , Colágeno/metabolismo , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Matriz Extracelular/metabolismo , Vesículas Extracelulares/genética , Ontologia Genética , Células Estreladas do Fígado/enzimologia , Histonas/genética , Histonas/metabolismo , Humanos , Queratinas/genética , Queratinas/metabolismo , Cirrose Hepática/genética , Masculino , Camundongos , Complexo de Endopeptidases do Proteassoma/metabolismo , Mapeamento de Interação de Proteínas , Proteoma/química , Proteômica , Ribossomos/metabolismo , Espectrometria de Massas em Tandem , Fatores de Tempo
9.
Cell Mol Life Sci ; 77(21): 4397-4411, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31912195

RESUMO

The isotype-specific composition of the keratin cytoskeleton is important for strong adhesion, force resilience, and barrier function of the epidermis. However, the mechanisms by which keratins regulate these functions are still incompletely understood. In this study, the role and significance of the keratin network for mechanical integrity, force transmission, and barrier formation were analyzed in murine keratinocytes. Following the time-course of single-cell wound closure, wild-type (WT) cells slowly closed the gap in a collective fashion involving tightly connected neighboring cells. In contrast, the mechanical response of neighboring cells was compromised in keratin-deficient cells, causing an increased wound area initially and an inefficient overall wound closure. Furthermore, the loss of the keratin network led to impaired, fragmented cell-cell junctions, and triggered a profound change in the overall cellular actomyosin architecture. Electric cell-substrate impedance sensing of cell junctions revealed a dysfunctional barrier in knockout (Kty-/-) cells compared to WT cells. These findings demonstrate that Kty-/- cells display a novel phenotype characterized by loss of mechanocoupling and failure to form a functional barrier. Re-expression of K5/K14 rescued the barrier defect to a significant extent and reestablished the mechanocoupling with remaining discrepancies likely due to the low abundance of keratins in that setting. Our study reveals the major role of the keratin network for mechanical homeostasis and barrier functionality in keratinocyte layers.


Assuntos
Queratinócitos/citologia , Queratinas/metabolismo , Animais , Fenômenos Biomecânicos , Linhagem Celular , Epiderme/metabolismo , Epiderme/ultraestrutura , Deleção de Genes , Junções Intercelulares/genética , Junções Intercelulares/metabolismo , Junções Intercelulares/ultraestrutura , Queratinócitos/metabolismo , Queratinas/genética , Queratinas/ultraestrutura , Camundongos , Cicatrização
10.
Cell Mol Life Sci ; 77(3): 543-558, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31243490

RESUMO

Desmosome-anchored keratin intermediate filaments (KFs) are essential for epithelial coherence. Yet, desmosomal KF attachment and network organization are still unexplored in vivo. We, therefore, monitored KF network morphogenesis in fluorescent keratin 8 knock-in murine embryos revealing keratin enrichment at newly formed desmosomes followed by KF formation, KF elongation and KF fusion. To examine details of this process and its coupling to desmosome formation, we studied fluorescent keratin and desmosomal protein reporter dynamics in the periphery of expanding HaCaT keratinocyte colonies. Less than 3 min after the start of desmosomal proteins clustering non-filamentous keratin enriched at these sites followed by KF formation and elongation. Subsequently, desmosome-anchored KFs merged into stable bundles generating a rim-and-spokes system consisting of subcortical KFs connecting desmosomes to each other and radial KFs connecting desmosomes to the cytoplasmic KF network. We conclude that desmosomes are organizing centers for the KF cytoskeleton with a hitherto unknown nucleation capacity.


Assuntos
Desmossomos/metabolismo , Queratinas/metabolismo , Morfogênese/fisiologia , Animais , Adesão Celular/fisiologia , Linhagem Celular , Citoplasma/metabolismo , Proteínas do Citoesqueleto/metabolismo , Citoesqueleto/metabolismo , Humanos , Filamentos Intermediários/metabolismo , Queratinócitos/metabolismo , Camundongos
11.
Phys Rev Lett ; 123(18): 188102, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31763918

RESUMO

The cytoskeleton is a composite network of three types of protein filaments, among which intermediate filaments (IFs) are the most extensible ones. Two very important IFs are keratin and vimentin, which have similar molecular architectures but different mechanical behaviors. Here we compare the mechanical response of single keratin and vimentin filaments using optical tweezers. We show that the mechanics of vimentin strongly depends on the ionic strength of the buffer and that its force-strain curve suggests a high degree of cooperativity between subunits. Indeed, a computational model indicates that in contrast to keratin, vimentin is characterized by strong lateral subunit coupling of its charged monomers during unfolding of α helices. We conclude that cells can tune their mechanics by differential use of keratin versus vimentin.


Assuntos
Citoesqueleto/química , Queratinas/química , Modelos Biológicos , Vimentina/química , Fenômenos Biomecânicos , Tampões (Química) , Citoesqueleto/metabolismo , Queratinas/metabolismo , Microscopia de Força Atômica , Pinças Ópticas , Concentração Osmolar , Conformação Proteica em alfa-Hélice , Vimentina/metabolismo
12.
Oxid Med Cell Longev ; 2019: 1857086, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31641422

RESUMO

Our previous research revealed that trehalose, a nonreducing disaccharide of glucose and an important stress responsive factor, proved to have anti-inflammatory, antiapoptotic, and particularly antioxidant properties in UVB-irradiated corneas. Trehalose reduced oxidative stress in corneas induced by UVB irradiation, by means of a decrease in the antioxidant/prooxidant imbalance in the corneal epithelium. In this study, we demonstrate that trehalose of 3% or 6% concentration in eye drops directly decreases oxidative stress in UVB-irradiated corneas, by removing the excessive amount of reactive oxygen species (ROS). Trehalose drops applied on corneas during UVB irradiation once daily for four days resulted in a reduction or even absence of the oxidative stress, DNA damage, and peroxynitrite formation (detected by nitrotyrosine residues), seen in buffer-treated corneas. Furthermore, trehalose treatment applied curatively after repeated irradiation for the subsequent fourteen days led to the renewal of corneal transparency and significant suppression or even absence of neovascularization. This was in contrast to buffer-treated irradiated corneas, where the intracorneal inflammation was developed and the untransparent corneas were vascularized. In conclusion, the treatment of UVB-irradiated corneas with trehalose eye drops removed the excessive amount of ROS in the corneal epithelium, leading to the suppression of oxidative stress and favorable corneal healing. The 6% trehalose showed a higher intensive antioxidant effect.


Assuntos
Córnea/patologia , Córnea/efeitos da radiação , Lesões da Córnea/tratamento farmacológico , Estresse Oxidativo , Trealose/uso terapêutico , Raios Ultravioleta , Cicatrização/efeitos dos fármacos , Animais , Córnea/efeitos dos fármacos , Dano ao DNA , Feminino , Interleucina-1beta/metabolismo , Queratinas/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Coelhos , Reepitelização/efeitos dos fármacos , Reepitelização/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Trealose/farmacologia , Tirosina/análogos & derivados , Tirosina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização/efeitos da radiação
13.
Essays Biochem ; 63(5): 521-533, 2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31652439

RESUMO

Migration of epithelial cells is fundamental to multiple developmental processes, epithelial tissue morphogenesis and maintenance, wound healing and metastasis. While migrating epithelial cells utilize the basic acto-myosin based machinery as do other non-epithelial cells, they are distinguished by their copious keratin intermediate filament (KF) cytoskeleton, which comprises differentially expressed members of two large multigene families and presents highly complex patterns of post-translational modification. We will discuss how the unique mechanophysical and biochemical properties conferred by the different keratin isotypes and their modifications serve as finely tunable modulators of epithelial cell migration. We will furthermore argue that KFs together with their associated desmosomal cell-cell junctions and hemidesmosomal cell-extracellular matrix (ECM) adhesions serve as important counterbalances to the contractile acto-myosin apparatus either allowing and optimizing directed cell migration or preventing it. The differential keratin expression in leaders and followers of collectively migrating epithelial cell sheets provides a compelling example of isotype-specific keratin functions. Taken together, we conclude that the expression levels and specific combination of keratins impinge on cell migration by conferring biomechanical properties on any given epithelial cell affecting cytoplasmic viscoelasticity and adhesion to neighboring cells and the ECM.


Assuntos
Movimento Celular/fisiologia , Células Epiteliais/metabolismo , Filamentos Intermediários/metabolismo , Queratinas/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Animais , Desmossomos/metabolismo , Hemidesmossomos/metabolismo , Humanos , Cicatrização/fisiologia
14.
Dev Cell ; 51(3): 326-340.e4, 2019 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-31564613

RESUMO

Oil-secreting sebaceous glands (SGs) are critical for proper skin function; however, it remains unclear how different factors act together to modulate SG stem cells. Here, we provide functional evidence that each SG lobe is serviced by its own dedicated stem cell population. Upon ablating Notch signaling in different skin subcompartments, we find that this pathway exerts dual counteracting effects on SGs. Suppressing Notch in SG progenitors traps them in a hybrid state where stem and differentiation features become intermingled. In contrast, ablating Notch outside of the SG stem cell compartment indirectly drives SG expansion. Finally, we report that a K14:K5→K14:K79 keratin shift occurs during SG differentiation. Deleting K79 destabilizes K14 in sebocytes, and attenuates SGs and eyelid meibomian glands, leading to corneal ulceration. Altogether, our findings demonstrate that SGs integrate diverse signals from different niches and suggest that mutations incurred within one stem cell compartment can indirectly influence another.


Assuntos
Glândulas Sebáceas/citologia , Pele/citologia , Nicho de Células-Tronco , Células-Tronco/citologia , Animais , Diferenciação Celular , Feminino , Proteínas Hedgehog/metabolismo , Proteína de Ligação a Sequências Sinal de Recombinação J de Imunoglobina/metabolismo , Queratinas/metabolismo , Masculino , Glândulas Tarsais/metabolismo , Camundongos Knockout , Mutação/genética , Receptores Notch/genética
15.
Ann Diagn Pathol ; 43: 151402, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31473371

RESUMO

Heck's disease (focal or multifocal epithelial hyperplasia) is a benign, rare condition of the skin and mucous membranes induced by human papillomavirus (HPV) infection. Other entities that can induce large papillomatous lesions that involve the mucous membranes and skin include condyloma acuminatum, which is sexually transmitted, and white sponge nevus, often due to a mutation of cytokeratin 4 or 13. Six cases diagnosed as either Heck's disease (n = 2) or white sponge nevus (n = 4) and 6 oral condyloma were compared on histologic grounds and analyzed in situ for HPV DNA, including HPVs 6,11, and 13, as well as cytokeratins 4 and 13. Each case showed marked acanthosis, and para/hyperkeratosis. More variable histologic findings included rete ridge elongation, keratinocyte degeneration, and perinuclear halos. High copy HPV 13 DNA was evident in the squamous cells towards the surface in the two cases diagnosed as Heck's disease and in two cases diagnosed as white sponge nevus on clinical grounds. HPV 6/11 was found in each of the six condyloma. Marked decrease in either cytokeratin 4 or 13 was evident in the two cases diagnosed as white sponge nevus that were HPV DNA negative. It is concluded that in situ hybridization analyses including HPVs 6, 11, and 13 as well as immunohistochemistry for cytokeratins 4 and 13 can differentiate Heck's disease from condyloma and white sponge nevus, which can be difficult to differentiate on clinical and histologic grounds.


Assuntos
Condiloma Acuminado/patologia , Leucoceratose da Mucosa Hereditária/patologia , Nevo/patologia , Pele/patologia , Adulto , Biomarcadores/metabolismo , Diferenciação Celular , Condiloma Acuminado/virologia , DNA Viral/genética , Feminino , Hiperplasia Epitelial Focal/patologia , Humanos , Hiperplasia/patologia , Hibridização In Situ , Queratinas/metabolismo , Leucoceratose da Mucosa Hereditária/genética , Leucoceratose da Mucosa Hereditária/virologia , Masculino , Pessoa de Meia-Idade , Nevo/virologia , Papiloma/patologia , Papillomaviridae/genética , Infecções por Papillomavirus/patologia
16.
Med Mycol J ; 60(3): 71-74, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474693

RESUMO

Tinea pedis and tinea unguium are the most common dermatophytoses seen in the daily practice of dermatology. According to a report in Japan Foot Week 2006, it is estimated that about 1 in 5 Japanese have tinea pedis and that about 1 in 10 have tinea unguium. Thus far, use of oral antifungal agents has been the first-line therapy for onychomycosis. Many patients with onychomycosis, however, are elderly and have concomitant diseases as well as liver function disorder. Moreover, oral medications are reportedly associated with risks of impaired liver function and interactions. Due to such risks, therefore, treatment with topical agents is the only applicable therapy for most patients with onychomycosis. Recently, two topical agents (efinaconazole in 2014 and luliconazole in 2016) have been approved for the treatment of onychomycosis in Japan. Efinaconazole 10% solution is a triazole antifungal drug developed in Japan. Due to its low keratin affinity, efinaconazole shows high transungual penetration into nails and retains a high antifungal activity in the nail plate and the nail bed. Luliconazole 5% solution is an imidazole antifungal agent that has high keratin affinity. Luliconazole has also been shown in vitro to permeate from the superficial to the deep layers of the nail and to achieve concentrations above the MIC in all layers of the nail. Both efinaconazole 10% solution and luliconazole 5% solution have high antifungal activities for Trichophyton species. These two topical agents, therefore, have certainly increased treatment options for onychomycosis in the daily practice of dermatology.


Assuntos
Antifúngicos/administração & dosagem , Imidazóis/administração & dosagem , Onicomicose/tratamento farmacológico , Triazóis/administração & dosagem , Administração Tópica , Farmacorresistência Fúngica , Humanos , Imidazóis/metabolismo , Queratinas/metabolismo , Unhas/metabolismo , Onicomicose/microbiologia , Soluções , Triazóis/metabolismo , Trichophyton/efeitos dos fármacos
17.
Int J Mol Sci ; 20(18)2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31540219

RESUMO

During the peri-implantation period, multinucleated syncytia are formed in the sheep placenta. For over 20 years the scientific consensus has been that during trophoblast syncytialization in sheep, binucleate trophoblast giant cells (BNCs) differentiate from mononuclear trophoblast cells, and individual BNCs fuse with individual luminal epithelial (LE) cells to form trinucleate cells. These trophoblast-LE syncytial plaques then grow through continued BNC migration and fusion. Therefore, LE cells are thought to be incorporated into syncytial plaques. However, these ideas were based on electron microscopy studies, without benefit of molecular markers for BNC and LE cells to support conclusions. The aim of this study was to observe interactions between BNCs and uterine LE cells using immunohistochemical localization for molecular markers for BNCs and uterine LE cells. We performed immunofluorescence staining, laser capture microdissection, and TUNEL staining on the uterine-placental tissues of sheep during early placentation. We observed: (1) syncytial cells containing more than two nuclei within the trophoblast cell layer; (2) depolarized LE cells that express caspase 3 and stain positively for TUNEL; (3) engulfment of caspase 3-positive LE cells by trophoblast giant cells (TGCs) and empty spaces within the LE layer at sites of implantation; (4) rapid enlargement of syncytial plaques; and (5) E-cadherin and TUNEL-positive cells within the uterine stroma underlying degenerating LE was coincident with accumulation of CD45-positive cells at these sites. These data suggest that during early placentation: (1) fusion between trophoblasts is not limited to the formation of BNCs, and the term 'trophoblast giant cell (TGC)' may be appropriate; (2) LE cells undergo apoptosis; (3) apoptotic LE cells are eliminated by TGCs; (4) fusion is not limited to the incorporation of new BNCs but involves the lateral fusion between growing syncytial plaques; and (5) TGCs carry apoptotic LE cells away from the uterine-placental interface for elimination by immune cells within the stroma. These data indicate that uterine LE cells are not incorporated into syncytial plaques, but are engulfed and eliminated, and that early placentation in sheep is more similar to early placentation in humans than is currently understood in that both develop mononucleated cytotrophoblast and multinucleated syncytiotrophoblast layers of entirely placental origin. The elimination of LE cells by sheep TGCs might provide insights into elimination and penetration of LE cells during human embryo implantation.


Assuntos
Biomarcadores/metabolismo , Células Epiteliais/citologia , Células Gigantes/citologia , Placentação , Trofoblastos/citologia , Animais , Caderinas/metabolismo , Caspase 3/metabolismo , Diferenciação Celular , Fusão Celular , Movimento Celular , Células Epiteliais/metabolismo , Feminino , Células Gigantes/metabolismo , Imuno-Histoquímica , Queratinas/metabolismo , Antígenos Comuns de Leucócito/metabolismo , Placenta/citologia , Placenta/metabolismo , Gravidez , Ovinos , Trofoblastos/metabolismo
18.
Int J Mol Sci ; 20(19)2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31554264

RESUMO

Epithelial keratinization involves complex cellular modifications that provide protection against pathogens and chemical and mechanical injuries. In the oral cavity, keratinized mucosa is also crucial to maintain healthy periodontal or peri-implant tissues. In this study, we investigated the roles of type XVIII collagen, a collagen-glycosaminoglycan featuring an extracellular matrix component present in the basement membrane, in oral mucosal keratinization. Histological analysis of keratinized and non-keratinized oral mucosa showed that type XVIII collagen was highly expressed in keratinized mucosa. Additionally, a 3D culture system using human squamous carcinoma cells (TR146) was used to evaluate and correlate the changes in the expression of type XVIII collagen gene, COL18A1, and epithelial keratinization-related markers, e.g., keratin 1 (KRT1) and 10 (KRT10). The results showed that the increase in COL18A1 expression followed the increase in KRT1 and KRT10 mRNA levels. Additionally, loss-of-function analyses using silencing RNA targeting COL18A1 mRNA and a Col18-knockout (KO) mouse revealed that the absence of type XVIII collagen induces a dramatic decrease in KRT10 expression as well as in the number and size of keratohyalin granules. Together, the results of this study demonstrate the importance of type XVIII collagen in oral mucosal keratinization.


Assuntos
Colágeno Tipo XVIII/metabolismo , Grânulos Citoplasmáticos/metabolismo , Queratinas/metabolismo , Mucosa Bucal/metabolismo , Animais , Biomarcadores , Diferenciação Celular/genética , Colágeno Tipo VIII/genética , Colágeno Tipo VIII/metabolismo , Colágeno Tipo XVIII/genética , Imunofluorescência , Humanos , Camundongos , Camundongos Knockout
19.
World Neurosurg ; 132: 173-176, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31491571

RESUMO

BACKGROUND: Epidermoid cysts of the spinal cord may rupture, resulting in keratin dissemination in the subarachnoid space, in the ventricles, and along the central canal of the spinal cord causing meningitis, myelopathic changes, or hydrocephalus. CASE DESCRIPTION: A 53-year-old woman with no past medical history presented with a 2-week history of headache located in the occipital region associated with neck pain. Brain magnetic resonance imaging demonstrated multiple fat droplets scattered throughout the subarachnoid and intraventricular spaces with significant edema of the right posterior temporoparietal lobes with trapping of the right temporal horn of the lateral ventricle and atrium. An intracranial lesion could not be observed in the study. The spinal region was suspected as the possible culprit, and spinal imaging showed a large cystic lesion at the level of the conus medullaris. The patient underwent neuronavigation endoscopic exploration of the right lateral ventricle with flushing of the keratin particles followed by a posterior lumbar decompression with resection of the epidermoid cyst. Pathology was consistent with an epidermoid cyst. Successful recovery with improvement in symptoms was quickly observed. CONCLUSIONS: When an epidermoid cyst is suspected but no intracranial lesion is found, the intraspinal area should be studied. Rupture of a spinal epidermoid cyst may cause meningitis and inflammation producing obstructive hydrocephalus. We present this rare entity and describe the diagnostic and surgical techniques used.


Assuntos
Cisto Epidérmico/complicações , Hidrocefalia/etiologia , Hidrocefalia/cirurgia , Meningite/etiologia , Procedimentos Neurocirúrgicos/métodos , Doenças da Coluna Vertebral/complicações , Ventrículos Cerebrais/metabolismo , Ventrículos Cerebrais/patologia , Descompressão Cirúrgica , Endoscopia , Feminino , Humanos , Queratinas/metabolismo , Imagem por Ressonância Magnética , Pessoa de Meia-Idade , Neuronavegação , Ruptura , Espaço Subaracnóideo/metabolismo , Espaço Subaracnóideo/patologia , Resultado do Tratamento
20.
J Comp Pathol ; 171: 24-29, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31540622

RESUMO

A neutered female domestic shorthaired cat was presented for a rapidly growing left cervical mass and a 6-month history of primary hyperthyroidism. Cytological examination of the mass was consistent with a sarcoma. Due to poor clinical response the cat was humanely destroyed and a post-mortem examination was performed. This revealed a markedly enlarged, irregularly shaped left thyroid gland with signs of infiltration of the trachea. The contralateral (right) thyroid was also moderately enlarged and irregularly shaped. Histopathological examination of the cervical masses indicated bilateral thyroid carcinosarcomas, evidenced by positive immunohistochemical labelling for vimentin, pan-cytokeratin and thyroid transcription factor-1 of the appropriate cell populations. The cat also had a concurrent pulmonary adenocarcinoma (papillary-lepidic type), unrelated to the thyroid neoplasm. Thyroid carcinosarcoma is an uncommonly recorded canine and human neoplasm and this is the first case of this entity to be reported in a cat.


Assuntos
Carcinossarcoma/veterinária , Doenças do Gato/patologia , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/veterinária , Animais , Carcinossarcoma/metabolismo , Carcinossarcoma/patologia , Doenças do Gato/metabolismo , Gatos , Feminino , Queratinas/metabolismo , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Vimentina/metabolismo
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