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1.
PLoS One ; 15(8): e0234672, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764753

RESUMO

Opticin is a class III member of the extracellular matrix small leucine-rich repeat protein/proteoglycan (SLRP) family found in vitreous humour and cartilage. It was first identified associated with the surface of vitreous collagen fibrils and several other SLRPs are also known to bind collagen fibrils and it some cases alter fibril morphology. The purpose of this study was to investigate the binding of opticin to the collagen II-containing fibrils found in vitreous and cartilage. Electron microscopic studies using gold labelling demonstrated that opticin binds vitreous and thin cartilage collagen fibrils specifically at a single site in the gap region of the collagen D-period corresponding to the e2 stain band; this is the first demonstration of the binding site of a class III SLRP on collagen fibrils. Opticin did not bind thick cartilage collagen fibrils from cartilage or tactoids formed in vitro from collagen II, but shows high specificity for thin, heterotypic collagen fibrils containing collagens II, and XI or V/XI. Vitreous collagen fibrils from opticin null and wild-type mice were compared and no difference in fibril morphology or diameter was observed. Similarly, in vitro fibrillogenesis experiments showed that opticin did not affect fibril formation. We propose that when opticin is bound to collagen fibrils, rather than influencing their morphology it instead hinders the binding of other molecules to the fibril surfaces and/or act as an intermediary bridge linking the collagen fibrils to other non-collagenous molecules.


Assuntos
Colágeno/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Proteoglicanas/metabolismo , Animais , Sítios de Ligação , Bovinos , Colágeno/química , Colágeno/ultraestrutura , Proteínas da Matriz Extracelular/química , Proteínas da Matriz Extracelular/deficiência , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Microscopia Imunoeletrônica , Ligação Proteica , Proteoglicanas/química , Proteoglicanas/deficiência , Corpo Vítreo/química , Corpo Vítreo/metabolismo , Corpo Vítreo/ultraestrutura
2.
Science ; 369(6499): 71-77, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32527924

RESUMO

Bacterial biofilms represent a basic form of multicellular organization that confers survival advantages to constituent cells. The sequential stages of cell ordering during biofilm development have been studied in the pathogen and model biofilm-former Vibrio cholerae It is unknown how spatial trajectories of individual cells and the collective motions of many cells drive biofilm expansion. We developed dual-view light-sheet microscopy to investigate the dynamics of biofilm development from a founder cell to a mature three-dimensional community. Tracking of individual cells revealed two distinct fates: one set of biofilm cells expanded ballistically outward, while the other became trapped at the substrate. A collective fountain-like flow transported cells to the biofilm front, bypassing members trapped at the substrate and facilitating lateral biofilm expansion. This collective flow pattern was quantitatively captured by a continuum model of biofilm growth against substrate friction. Coordinated cell movement required the matrix protein RbmA, without which cells expanded erratically. Thus, tracking cell lineages and trajectories in space and time revealed how multicellular structures form from a single founder cell.


Assuntos
Biofilmes , Vibrio cholerae/citologia , Vibrio cholerae/fisiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Microscopia , Movimento (Física) , Mutação , Análise de Célula Única/métodos , Vibrio cholerae/genética
3.
PLoS One ; 15(6): e0233962, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32525899

RESUMO

High grade serous ovarian cancer (HGSC) is the most common and deadly type of ovarian cancer, largely due to difficulties in early diagnosis and rapid metastasis throughout the peritoneal cavity. Previous studies have shown that expression of Notch3 correlates with worse prognosis and increased tumorigenic cell behaviors in HGSC. We investigated the mechanistic role of Notch3 in a model of metastatic ovarian cancer using the murine ovarian surface epithelial cell line, ID8 IP2. Notch3 was activated in ID8 IP2 cells via expression of the Notch3 intracellular domain (Notch3IC). Notch3IC ID8 IP2 cells injected intraperitoneally caused accelerated ascites and reduced survival compared to control ID8 IP2, particularly in early stages of disease. We interrogated downstream targets of Notch3IC in ID8 IP2 cells by RNA sequencing and found significant induction of genes that encode adhesion and extracellular matrix proteins. Notch3IC ID8 IP2 showed increased expression of ITGA1 mRNA and cell-surface protein. Notch3IC-mediated increase of ITGA1 was also seen in two human ovarian cancer cells. Notch3IC ID8 IP2 cells showed increased adhesion to collagens I and IV in vitro. We propose that Notch3 activation in ovarian cancer cells causes increased adherence to collagen-rich peritoneal surfaces. Thus, the correlation between increased Notch3 signaling and poor prognosis may be influenced by increased metastasis of HGSC via increased adherence of disseminating cells to new metastatic sites in the peritoneum.


Assuntos
Carcinoma Epitelial do Ovário/secundário , Cistadenocarcinoma Seroso/secundário , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/secundário , Receptor Notch3/metabolismo , Animais , Carcinogênese/metabolismo , Carcinoma Epitelial do Ovário/metabolismo , Adesão Celular , Linhagem Celular Tumoral , Cistadenocarcinoma Seroso/metabolismo , Progressão da Doença , Proteínas da Matriz Extracelular/metabolismo , Feminino , Humanos , Camundongos , Camundongos Nus , Neoplasias Ovarianas/metabolismo , Neoplasias Peritoneais/metabolismo , Receptor Notch3/genética
4.
PLoS One ; 15(6): e0232111, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579557

RESUMO

Glaucoma is the second leading cause of irreversible blindness worldwide. Primary open angle glaucoma (POAG), the most common form of glaucoma, is often associated with elevation of intraocular pressure (IOP) due to the dysfunction of trabecular meshwork (TM) tissues. Currently, an ex vivo human anterior segment perfusion cultured system is widely used to study the effects of glaucoma factors and disease modifying drugs on physiological parameters like aqueous humor (AH) dynamics and IOP homeostasis. This system requires the use of freshly enucleated intact human eyes, which are sparsely available at very high cost. In this study, we explored the feasibility of using human donor corneoscleral segments for modeling morphological and biochemical changes associated with POAG. Among the number of corneas donated each year, many are deemed ineligible for transplantation due to stringent acceptance criteria. These ineligible corneoscleral segments were obtained from the Lions Eye Bank, Tampa, Florida. Each human donor anterior corneoscleral segment was dissected into four equal quadrants and cultured for 7 days by treating with the glaucoma factors dexamethasone (Dex) or recombinant transforming growth factor (TGF) ß2 or transduced with lentiviral expression vectors containing wild type (WT) and mutant myocilin. Hematoxylin and Eosin (H&E) staining analysis revealed that the TM structural integrity is maintained after 7 days in culture. Increased TUNEL positive TM cells were observed in corneoscleral quadrants treated with glaucoma factors compared to their respective controls. However, these TUNEL positive cells were mainly confined to the scleral region adjacent to the TM. Treatment of corneoscleral quadrants with Dex or TGFß2 resulted in glaucomatous changes at the TM, which included increased extracellular matrix (ECM) proteins and induction of endoplasmic reticulum (ER) stress. Western blot analysis of the conditioned medium showed an increase in ECM (fibronectin and collagen IV) levels in Dex- or TGFß2-treated samples compared to control. Lentiviral transduction of quadrants resulted in expression of WT and mutant myocilin in TM tissues. Western blot analysis of conditioned medium revealed decreased secretion of mutant myocilin compared to WT myocilin. Moreover, increased ECM deposition and ER stress induction was observed in the TM of mutant myocilin transduced quadrants. Our findings suggest that the ex-vivo cultured human corneoscleral segment model is cost-effective and can be used as a pre-screening tool to study the effects of glaucoma factors and anti-glaucoma therapeutics on the TM.


Assuntos
Dexametasona/farmacologia , Limbo da Córnea/metabolismo , Malha Trabecular/efeitos dos fármacos , Fator de Crescimento Transformador beta2/farmacologia , Apoptose/efeitos dos fármacos , Células Cultivadas , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Proteínas da Matriz Extracelular/metabolismo , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Glaucoma de Ângulo Aberto/patologia , Glicoproteínas/genética , Glicoproteínas/metabolismo , Humanos , Limbo da Córnea/citologia , Limbo da Córnea/efeitos dos fármacos , Malha Trabecular/metabolismo , Malha Trabecular/patologia , Regulação para Cima/efeitos dos fármacos
5.
Proc Natl Acad Sci U S A ; 117(27): 15827-15836, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32571911

RESUMO

Bromine and peroxidasin (an extracellular peroxidase) are essential for generating sulfilimine cross-links between a methionine and a hydroxylysine within collagen IV, a basement membrane protein. The sulfilimine cross-links increase the structural integrity of basement membranes. The formation of sulfilimine cross-links depends on the ability of peroxidasin to use bromide and hydrogen peroxide substrates to produce hypobromous acid (HOBr). Once a sulfilimine cross-link is created, bromide is released into the extracellular space and becomes available for reutilization. Whether the HOBr generated by peroxidasin is used very selectively for creating sulfilimine cross-links or whether it also causes oxidative damage to bystander molecules (e.g., generating bromotyrosine residues in basement membrane proteins) is unclear. To examine this issue, we used nanoscale secondary ion mass spectrometry (NanoSIMS) imaging to define the distribution of bromine in mammalian tissues. We observed striking enrichment of bromine (79Br, 81Br) in basement membranes of normal human and mouse kidneys. In peroxidasin knockout mice, bromine enrichment of basement membranes of kidneys was reduced by ∼85%. Proteomic studies revealed bromination of tyrosine-1485 in the NC1 domain of α2 collagen IV from kidneys of wild-type mice; the same tyrosine was brominated in collagen IV from human kidney. Bromination of tyrosine-1485 was reduced by >90% in kidneys of peroxidasin knockout mice. Thus, in addition to promoting sulfilimine cross-links in collagen IV, peroxidasin can also brominate a bystander tyrosine. Also, the fact that bromine enrichment is largely confined to basement membranes implies that peroxidasin activity is largely restricted to basement membranes in mammalian tissues.


Assuntos
Membrana Basal/metabolismo , Bromo/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Peroxidase/metabolismo , Animais , Biópsia , Bromatos/metabolismo , Brometos , Células Cultivadas , Colágeno Tipo IV/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Iminas/metabolismo , Rim/citologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteômica
6.
J Vis Exp ; (160)2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32568229

RESUMO

Traumatic peripheral nervous system (PNS) injuries currently lack suitable treatments to regain full functional recovery. Schwann cells (SCs), as the major glial cells of the PNS, play a vital role in promoting PNS regeneration by dedifferentiating into a regenerative cell phenotype following injury. However, the dedifferentiated state of SCs is challenging to maintain through the time-period needed for regeneration and is impacted by changes in the surrounding extracellular matrix (ECM). Therefore, determining the complex interplay between SCs and differing ECM to provide cues of regenerative potential of SCs is essential. To address this, a strategy was created where different ECM proteins were adsorbed onto a tunable polydimethylsiloxane (PDMS) substrate which provided a platform where stiffness and protein composition can be modulated. SCs were seeded onto the tunable substrates and critical cellular functions representing the dynamics of SC phenotype were measured. To illustrate the interplay between SC protein expression and cellular morphology, differing seeding densities of SCs in addition to individual microcontact printed cellular patterns were utilized and characterized by immunofluorescence staining and western blot. Results showed that cells with a smaller spreading area and higher extent of cellular elongation promoted higher levels of SC regenerative phenotypic markers. This methodology not only begins to unravel the significant relationship between the ECM and cellular function of SCs, but also provides guidelines for the future optimization of biomaterials in peripheral nerve repair.


Assuntos
Matriz Extracelular/metabolismo , Fenótipo , Células de Schwann/citologia , Animais , Proliferação de Células , Proteínas da Matriz Extracelular/metabolismo
7.
Life Sci ; 256: 117955, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32534038

RESUMO

AIMS: Cancer associated fibroblasts (CAFs) play a crucial role in lung tumor development, but the underlying mechanism is still not fully understood. MAIN METHODS: SCRIB expression in the CAFs of human lung cancer tissues was examined by immunohistochemistry (IHC). A coculture of mouse Lewis lung cancer cells (LLC) and fibroblasts was used to investigate SCRIB expression in cocultured fibroblasts. Proliferation, scratch wound, and transwell assays were used to examine the proliferation, migration and invasion ability of SCRIB knockdown fibroblasts and their effects on LLC. A 3D-coculture system and co-injection xenograft model were used to examine LLC invasion. RNA sequencing and transwell experiments were used to explore the molecules that may participate in LLC invasion. KEY FINDINGS: Herein, we found that the low expression of SCRIB in CAFs is correlated with advanced tumor stages and poor survival for human lung squamous cell carcinoma. SCRIB expression in fibroblasts is drastically downregulated by LLC cells. SCRIB knockdown fibroblasts not only enhance invasion but also facilitate LLC invasion in a 3D-coculture system and in an in vivo subcutaneous transplantation model. The upregulation of asporin in SCRIB knockdown fibroblasts is involved in LLC invasion in vitro. SIGNIFICANCE: Collectively, the results indicate that fibroblasts with low SCRIB expression promote lung cancer cell invasion, which suggests that the downregulated expression of SCRIB may represent one of the important characteristics of tumor-promoting CAFs in lung squamous cell cancer.


Assuntos
Fibroblastos Associados a Câncer/metabolismo , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteínas de Membrana/genética , Proteínas Supressoras de Tumor/genética , Animais , Fibroblastos Associados a Câncer/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Regulação para Baixo/genética , Proteínas da Matriz Extracelular/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Modelos Biológicos , Invasividade Neoplásica , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Supressoras de Tumor/metabolismo
8.
Int J Nanomedicine ; 15: 2501-2513, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368037

RESUMO

Purpose: The extracellular matrix (ECM) labyrinthine network secreted by mesenchymal stem cells (MSCs) provides a microenvironment that enhances cell adherence, proliferation, viability, and differentiation. The potential of graphene-based nanomaterials to mimic a tissue-specific ECM has been recognized in designing bone tissue engineering scaffolds. In this study, we investigated the expression of specific ECM proteins when human fat-derived adult MSCs adhered and underwent osteogenic differentiation in the presence of functionalized graphene nanoparticles. Methods: Graphene nanoparticles with 6-10% oxygen content were prepared and characterized by XPS, FTIR, AFM and Raman spectroscopy. Calcein-am and crystal violet staining were performed to evaluate viability and proliferation of human fat-derived MSCs on graphene nanoparticles. Alizarin red staining and quantitation were used to determine the effect of graphene nanoparticles on osteogenic differentiation. Finally, immunofluorescence assays were used to investigate the expression of ECM proteins during cell adhesion and osteogenic differentiation. Results: Our data show that in the presence of graphene, MSCs express specific integrin heterodimers and exhibit a distinct pattern of the corresponding bone-specific ECM proteins, primarily fibronectin, collagen I and vitronectin. Furthermore, MSCs undergo osteogenic differentiation spontaneously without any chemical induction, suggesting that the physicochemical properties of graphene nanoparticles might trigger the expression of bone-specific ECM. Conclusion: Understanding the cell-graphene interactions resulting in an osteogenic niche for MSCs will significantly improve the application of graphene nanoparticles in bone repair and regeneration.


Assuntos
Proteínas da Matriz Extracelular/metabolismo , Grafite/farmacologia , Células-Tronco Mesenquimais/metabolismo , Nanopartículas/química , Osteogênese/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Integrinas/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Oxigênio/química , Espectroscopia Fotoeletrônica , Multimerização Proteica
9.
Prostate ; 80(10): 753-763, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32421868

RESUMO

BACKGROUND: Although thrombospondins 4 (THBS4) participates in controlling the biology of prostate cancer (PCa), the mechanism underlying this regulation remains unknown. Hence, this study aims to identify the regulatory effects of THBS4 on the PCa stem cell-like properties and the potential mechanism associated with the phosphatidylinositol 3'-kinase (PI3K)/protein kinase B (Akt) pathway. METHODS: PCa stem cells were sorted and identified using flow cytometry and THBS4 expression in the identified PCa stem cells was measured using Western blot assay. THBS4 was overexpressed or silenced in PCa stem cells, following which, self-renewal, proliferation, cell cycle distribution, and apoptosis of PCa stem cells were assessed as well as tumorigenicity in vivo was evaluated. PI3K/Akt pathway inhibitor was applied to identify its involvement in the regulatory roles of THBS4 in PCa stem cells. RESULTS: THBS4 was expressed at a higher level in PCa stem cells than in PCa cells. The overexpression of THBS4 promoted the self-renewal and proliferation, curbed the apoptosis of PCa stem cells, and enhanced the in vivo tumorigenicity, which was achieved by activating the PI3K/Akt pathway. On the contrary, short-hairpin RNA-mediated silencing of THBS4 exhibited suppressive effects on those cancer stem cell (CSC)-like properties and promotive effects on their apoptosis. CONCLUSION: THBS4 silencing can impede the CSC-like properties in PCa via blockade of the PI3K/Akt pathway, which provides patients with PCa a new therapeutic target.


Assuntos
Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Trombospondinas/metabolismo , Antígeno AC133/biossíntese , Animais , Linhagem Celular Tumoral , Proteínas da Matriz Extracelular/biossíntese , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Perfilação da Expressão Gênica , Inativação Gênica , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Células PC-3 , Neoplasias da Próstata/genética , Transdução de Sinais , Trombospondinas/biossíntese , Trombospondinas/deficiência , Trombospondinas/genética
10.
Plast Reconstr Surg ; 145(6): 1037e-1049e, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32459770

RESUMO

BACKGROUND: The major intrinsic cause of facial skin degeneration is age, associated with extrinsic factors such as exposure to sun. Its major pathologic causes are degeneration of the elastin matrix, with loss of oxytalan and elaunin fibers in the subepidermal region, and actinic degeneration of elastin fibers that lose their functional properties in the deep dermis. Therapy using autologous adipose mesenchymal stem cells for regeneration of extracellular matrix in patients with solar elastosis was addressed in qualitative and quantitative analyses of the dermal elastic fiber system and the associated cells. METHODS: Mesenchymal stem cells were obtained from lipoaspirates, expanded in vitro, and introduced into the facial skin of patients submitted after 3 to 4 months to a face-lift operation. In the retrieved skin, immunocytochemical analyses quantified elastic matrix components; cathepsin K; matrix metalloproteinase 12 (macrophage metalloelastase); and the macrophage M2 markers CD68, CD206, and hemeoxygenase-1. RESULTS: A full de novo formation of oxytalan and elaunin fibers was observed in the subepidermal region, with reconstitution of the papillary structure of the dermal-epidermal junction. Elastotic deposits in the deep dermis were substituted by a normal elastin fiber network. The coordinated removal of the pathologic deposits and their substitution by the normal ones was concomitant with activation of cathepsin K and matrix metalloproteinase 12, and with expansion of the M2 macrophage infiltration. CONCLUSION: The full regeneration of solar elastosis was obtained by injection of in vitro expanded autologous adipose mesenchymal stem cells, which are appropriate, competent, and sufficient to elicit the full structural regeneration of the sun-aged skin. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.


Assuntos
Tecido Adiposo/citologia , Transplante de Células-Tronco Mesenquimais/métodos , Cuidados Pré-Operatórios/métodos , Ritidoplastia , Envelhecimento da Pele , Idoso , Biópsia , Brasil , Elastina/análise , Elastina/metabolismo , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/análise , Proteínas da Matriz Extracelular/metabolismo , Face , Feminino , Seguimentos , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Rejuvenescimento , Pele/patologia , Pele/efeitos da radiação , Luz Solar/efeitos adversos , Transplante Autólogo/métodos , Resultado do Tratamento
11.
PLoS One ; 15(5): e0233422, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32437418

RESUMO

SPARCL1 is a matricellular protein with anti-adhesive, anti-proliferative and anti-tumorigenic functions and is frequently downregulated in tumors such as colorectal carcinoma or non-small cell lung cancer. Studies have identified SPARCL1 as an angiocrine tumor suppressor secreted by tumor vessel endothelial cells, thereby exerting inhibitory activity on angiogenesis and tumor growth, in colorectal carcinoma. It is unknown whether SPARCL1 may exert these homeostatic functions in all organs and in other species. Therefore, SPARCL1 expression was comparatively analysed between humans and mice in a systematic manner. Murine Sparcl1 (mSparcl1) is most strongly expressed in the lung; expressed at an intermediate level in most organs, including the large intestine; and absent in the liver. In human tissues, SPARCL1 (hSPARCL1) was detected in all organs, with the strongest expression in the stomach, large intestine and lung, mostly consistent with the murine expression pattern. A striking difference between human and murine tissues was the absence of mSparcl1 expression in murine livers, while human livers showed moderate expression. Furthermore, mSparcl1 was predominantly associated with mural cells, whereas hSPARCL1 was detected in both mural and endothelial cells. Human SPARCL1 expression was downregulated in different carcinomas, including lung and colon cancers. In conclusion, this study revealed species-, organ- and cell-type-dependent expression of SPARCL1, suggesting that its function may not be similar between humans and mice.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Mucosa Intestinal/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Animais , Proteínas de Ligação ao Cálcio/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteínas da Matriz Extracelular/genética , Mucosa Gástrica , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Knockout , Especificidade de Órgãos , Especificidade da Espécie
12.
Breast Cancer Res ; 22(1): 39, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32357907

RESUMO

BACKGROUND: Altered signaling pathways typify breast cancer and serve as direct inputs to steroid hormone receptor sensors. We previously reported that phospho-Ser134-GR (pS134-GR) species are elevated in triple-negative breast cancer (TNBC) and cooperate with hypoxia-inducible factors, providing a novel avenue for activation of GR in response to local or cellular stress. METHODS: We probed GR regulation by factors (cytokines, growth factors) that are rich within the tumor microenvironment (TME). TNBC cells harboring endogenous wild-type (wt) or S134A-GR species were created by CRISPR/Cas knock-in and subjected to transwell migration, invasion, soft-agar colony formation, and tumorsphere assays. RNA-seq was employed to identify pS134-GR target genes that are regulated both basally (intrinsic) or by TGFß1 in the absence of exogenously added GR ligands. Regulation of selected basal and TGFß1-induced pS134-GR target genes was validated by qRT-PCR and chromatin immunoprecipitation assays. Bioinformatics tools were used to probe public data sets for expression of pS134-GR 24-gene signatures. RESULTS: In the absence of GR ligands, GR is transcriptionally activated via p38-dependent phosphorylation of Ser134 as a mechanism of homeostatic stress-sensing and regulated upon exposure of TNBC cells to TME-derived agents. The ligand-independent pS134-GR transcriptome encompasses TGFß1 and MAPK signaling gene sets associated with TNBC cell survival and migration/invasion. Accordingly, pS134-GR was essential for TNBC cell anchorage-independent growth in soft-agar, migration, invasion, and tumorsphere formation, an in vitro readout of cancer stemness properties. Both pS134-GR and expression of the MAPK-scaffolding molecule 14-3-3ζ were essential for a functionally intact p38 MAPK signaling pathway downstream of MAP3K5/ASK1, indicative of a feedforward signaling loop wherein self-perpetuated GR phosphorylation enables cancer cell autonomy. A 24-gene pS134-GR-dependent signature induced by TGFß1 predicts shortened overall survival in breast cancer patients. CONCLUSIONS: Phospho-S134-GR is a critical downstream effector of p38 MAPK signaling and TNBC migration/invasion, survival, and stemness properties. Our studies define a ligand-independent role for GR as a homeostatic "sensor" of intrinsic stimuli as well as extrinsic factors rich within the TME (TGFß1) that enable potent activation of the p38 MAPK stress-sensing pathway and nominate pS134-GR as a therapeutic target in aggressive TNBC.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Receptores de Glucocorticoides/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Feminino , Edição de Genes , Humanos , Estadiamento de Neoplasias , Fosforilação , Transcriptoma , Neoplasias de Mama Triplo Negativas/metabolismo , Microambiente Tumoral
13.
Nat Cell Biol ; 22(7): 882-895, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32451439

RESUMO

It is well accepted that cancers co-opt the microenvironment for their growth. However, the molecular mechanisms that underlie cancer-microenvironment interactions are still poorly defined. Here, we show that Rho-associated kinase (ROCK) in the mammary tumour epithelium selectively actuates protein-kinase-R-like endoplasmic reticulum kinase (PERK), causing the recruitment and persistent education of tumour-promoting cancer-associated fibroblasts (CAFs), which are part of the cancer microenvironment. An analysis of tumours from patients and mice reveals that cysteine-rich with EGF-like domains 2 (CRELD2) is the paracrine factor that underlies PERK-mediated CAF education downstream of ROCK. We find that CRELD2 is regulated by PERK-regulated ATF4, and depleting CRELD2 suppressed tumour progression, demonstrating that the paracrine ROCK-PERK-ATF4-CRELD2 axis promotes the progression of breast cancer, with implications for cancer therapy.


Assuntos
Neoplasias da Mama/patologia , Fibroblastos Associados a Câncer/patologia , Moléculas de Adesão Celular/metabolismo , Reprogramação Celular , Proteínas da Matriz Extracelular/metabolismo , eIF-2 Quinase/metabolismo , Quinases Associadas a rho/metabolismo , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Moléculas de Adesão Celular/genética , Células Cultivadas , Modelos Animais de Doenças , Retículo Endoplasmático/metabolismo , Proteínas da Matriz Extracelular/genética , Feminino , Humanos , Camundongos , Comunicação Parácrina , eIF-2 Quinase/genética , Quinases Associadas a rho/genética
14.
Am J Physiol Renal Physiol ; 318(6): F1478-F1488, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32390515

RESUMO

Activation of immunological pathways and disturbances of extracellular matrix (ECM) dynamics are important contributors to the pathogenesis of chronic kidney diseases. Glomerular mesangial cells (MCs) are critical for homeostasis of glomerular ECM dynamics. Interleukin-6 (IL-6) can act as a pro/anti-inflammatory agent relative to cell types and conditions. This study investigated whether IL-6 influences ECM protein production by MCs and the regulatory pathways involved. Experiments were carried out in cultured human MCs (HMCs) and in mice. We found that overexpression of IL-6 and its receptor decreased the abundance of fibronectin and collagen type IV in MCs. ELISA and immunoblot analysis demonstrated that thapsigargin [an activator of store-operated Ca2+ entry (SOCE)], but not the endoplasmic reticulum stress inducer tunicamycin, significantly increased IL-6 content. This thapsigargin effect was abolished by GSK-7975A, a selective inhibitor of SOCE, and by silencing Orai1 (the channel protein mediating SOCE). Furthermore, inhibition of NF-κB pharmacologically and genetically significantly reduced SOCE-induced IL-6 production. Thapsigargin also stimulated nuclear translocation of the p65 subunit of NF-κB. Moreover, MCs overexpressing IL-6 and its receptor in HMCs increased the content of the glucagon-like peptide-1 receptor (GLP-1R), and IL-6 inhibition of fibronectin was attenuated by the GLP-1R antagonist exendin 9-39. In agreement with the HMC data, specific knockdown of Orai1 in MCs using the targeted nanoparticle delivery system in mice significantly reduced glomerular GLP-1R levels. Taken together, our results suggest a novel SOCE/NF-κB/IL-6/GLP-1R signaling pathway that inhibits ECM protein production by MCs.


Assuntos
Proteínas da Matriz Extracelular/metabolismo , Interleucina-6/metabolismo , Células Mesangiais/metabolismo , Receptores de Interleucina-6/metabolismo , Animais , Células Cultivadas , Regulação para Baixo , Proteínas da Matriz Extracelular/genética , Receptor do Peptídeo Semelhante ao Glucagon 1/genética , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Humanos , Interleucina-6/genética , Masculino , Camundongos Endogâmicos C57BL , NF-kappa B/genética , NF-kappa B/metabolismo , Proteína ORAI1/genética , Proteína ORAI1/metabolismo , Receptores de Interleucina-6/genética , Transdução de Sinais
15.
Adv Exp Med Biol ; 1245: 133-146, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32266656

RESUMO

The tumor microenvironment (TME) is rich in matrix components, growth factors, cytokines, and enzymatic modifiers that respond to changing conditions, to alter the fundamental properties of the tumor bed. Perlecan/HSPG2, a large, multi-domain heparan sulfate proteoglycan, is concentrated in the reactive stroma that surrounds tumors. Depending on its state in the TME, perlecan can either prevent or promote the progression of cancers to metastatic disease. Breast, prostate, lung, and renal cancers all preferentially metastasize to bone, a dense, perlecan-rich environment that is initially a "hostile" niche for cancer cells. Driven by inflammation, production of perlecan and its enzyme modifiers, which include matrix metalloproteinases (MMPs), sulfatases (SULFs), and heparanase (HPSE), increases in the reactive stroma surrounding growing and invading tumors. MMPs act upon the perlecan core protein, releasing bioactive fragments of the protein, primarily from C-terminal domains IV and V. These fragments influence cell adhesion, invasion, and angiogenesis. Sulfatases and heparanases act directly upon the heparan sulfate chains, releasing growth factors from reservoirs to reach receptors on the cancer cell surface. We propose that perlecan modifiers, by promoting the degradation of the perlecan-rich stroma, "flip the molecular switch" and convert the "hostile" stroma into a welcoming one that supports cancer dissemination and metastasis. Targeted therapies that prevent this molecular conversion of the TME should be considered as potential new therapeutics to limit metastasis.


Assuntos
Proteoglicanas de Heparan Sulfato/metabolismo , Neoplasias/metabolismo , Microambiente Tumoral , Proteínas da Matriz Extracelular/metabolismo , Heparitina Sulfato/metabolismo , Humanos , Metástase Neoplásica , Neoplasias/tratamento farmacológico , Neoplasias/patologia
16.
Invest Ophthalmol Vis Sci ; 61(3): 44, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32232343

RESUMO

Purpose: To determine the composition of extracellular matrix (ECM) proteins secreted by a conjunctival epithelial cell line and to identify components that aid conjunctival epithelial cell culture. Methods: Human conjunctival epithelial cell line (HCjE-Gi) cells were cultured in serum-free media and their ECM isolated using ammonium hydroxide. Growth characteristics were evaluated for fresh HCjE-Gi cells plated onto ECMs obtained from 3- to 28-day cell cultures. Mass spectrometry was used to characterize the ECM composition over 42 culture days. Cell adhesion and growth on pre-adsorbed fibronectin and α-2-HS-glycoprotein (α-2-HS-GP) were investigated. Results: Day 3 ECM provided the best substrate for cell growth compared to ECM obtained from 5- to 28-day cell cultures. Mass spectrometry identified a predominantly laminin 332 matrix throughout the time course, with progressive changes to matrix composition over time: proportional decreases in matrix-bound growth factors and increases in proteases. Fibronectin and α-2-HS-GP were 5- and 200-fold enriched as a proportion of the early ECM relative to the late ECM, respectively. Experiments on these proteins in isolation demonstrated that fibronectin supported rapid cell adhesion, whereas fibronectin and α-2-HS-GP both supported enhanced cell growth compared to tissue culture polystyrene. Conclusions: These data reveal α-2-HS-GP as a candidate protein to enhance the growth of conjunctival epithelial cells and raise the possibility of exploiting these findings for targeted improvement to synthetic tissue engineered conjunctival substrates.


Assuntos
Túnica Conjuntiva/metabolismo , Proteínas da Matriz Extracelular/metabolismo , alfa-2-Glicoproteína-HS/metabolismo , Biomarcadores/metabolismo , Adesão Celular/fisiologia , Contagem de Células , Linhagem Celular , Proliferação de Células/fisiologia , Túnica Conjuntiva/citologia , Meios de Cultura Livres de Soro , Células Epiteliais/metabolismo , Matriz Extracelular/metabolismo , Fibronectinas/metabolismo , Humanos , Espectrometria de Massas
17.
Proc Natl Acad Sci U S A ; 117(17): 9413-9422, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32291340

RESUMO

Astrogenesis is repressed in the early embryonic period and occurs in the late embryonic period. A variety of external and internal signals contribute to the sequential differentiation of neural stem cells. Here, we discovered that immune-related CD93 plays a critical negative role in the regulation of astrogenesis in the mouse cerebral cortex. We show that CD93 expression is detected in neural stem cells and neurons but not in astrocytes and declines as differentiation proceeds. Cd93 knockout increases astrogenesis at the expense of neuron production during the late embryonic period. CD93 responds to the extracellular matrix protein Multimerin 2 (MMRN2) to trigger the repression of astrogenesis. Mechanistically, CD93 delivers signals to ß-Catenin through a series of phosphorylation cascades, and then ß-Catenin transduces these signals to the nucleus to activate Zfp503 transcription. The transcriptional repressor ZFP503 inhibits the transcription of glial fibrillary acidic protein (Gfap) by binding to the Gfap promoter with the assistance of Grg5. Furthermore, Cd93 knockout mice exhibit autism-like behaviors. Taken together, our results reveal that CD93 is a negative regulator of the onset of astrogenesis and provide insight into therapy for psychiatric disorders.


Assuntos
Astrócitos/fisiologia , Proteínas da Matriz Extracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Glicoproteínas de Membrana/metabolismo , Subfamília D de Receptores Semelhantes a Lectina de Células NK/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Animais , Transtorno Autístico , Córtex Cerebral/citologia , Córtex Cerebral/embriologia , Eletroporação , Proteínas da Matriz Extracelular/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Inflamação , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos ICR , Subfamília D de Receptores Semelhantes a Lectina de Células NK/genética , Proteínas do Tecido Nervoso/genética , Neurogênese , Neuroglia , Gravidez
18.
Nat Commun ; 11(1): 1920, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32317643

RESUMO

Collagen-producing cells maintain the complex architecture of the lung and drive pathologic scarring in pulmonary fibrosis. Here we perform single-cell RNA-sequencing to identify all collagen-producing cells in normal and fibrotic lungs. We characterize multiple collagen-producing subpopulations with distinct anatomical localizations in different compartments of murine lungs. One subpopulation, characterized by expression of Cthrc1 (collagen triple helix repeat containing 1), emerges in fibrotic lungs and expresses the highest levels of collagens. Single-cell RNA-sequencing of human lungs, including those from idiopathic pulmonary fibrosis and scleroderma patients, demonstrate similar heterogeneity and CTHRC1-expressing fibroblasts present uniquely in fibrotic lungs. Immunostaining and in situ hybridization show that these cells are concentrated within fibroblastic foci. We purify collagen-producing subpopulations and find disease-relevant phenotypes of Cthrc1-expressing fibroblasts in in vitro and adoptive transfer experiments. Our atlas of collagen-producing cells provides a roadmap for studying the roles of these unique populations in homeostasis and pathologic fibrosis.


Assuntos
Colágeno/química , Pulmão/metabolismo , Fibrose Pulmonar/metabolismo , Animais , Separação Celular , Proteínas da Matriz Extracelular/metabolismo , Feminino , Fibroblastos/metabolismo , Citometria de Fluxo , Proteínas de Fluorescência Verde/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Fibrose Pulmonar Idiopática/patologia , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Fibrose Pulmonar/patologia , Transtornos Respiratórios/metabolismo , Análise de Célula Única
19.
Am J Respir Cell Mol Biol ; 63(2): 255-265, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32320626

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a lethal, medically refractory syndrome characterized by intrapulmonary accumulations of extracellular matrix (ECM) proteins produced by fibroblasts. Activation, clonal expansion, and differentiation of lymphocytes are also frequently present in IPF. Activated T cells are known to exert several effects that promote ECM production, but opposing homeostatic actions, wherein T cells can inhibit fibrosis, are less well understood. We found that CD27, a TNF receptor ubiquitously expressed on naive T cells, is downregulated on CD4 T cells of patients with IPF and that CD70, the sole ligand for CD27, is present on human pulmonary fibroblasts. We hypothesized that cognate engagements between lymphocyte CD27 and fibroblast CD70 could have functional consequences. Accordingly, a series of subsequent studies were conducted to examine the possible role of CD27-CD70 interactions in the regulation of fibrogenesis. Using IB, flow cytometry, RT-PCR, and kinomic assays, we found that fibroblast CD70 expression was inversely correlated with cell density and upregulated by TGF-ß1 (transforming growth factor-ß1). CD70 agonists, including T-cell-derived soluble CD27, markedly diminished fibroblast collagen and fibronectin synthesis, and these effects were potent enough to also inhibit profibrotic actions of TGF-ß1 on ECM production in vitro and in two distinct ex vivo human skin models. CD70 activation was mediated by AKT (protein kinase B) and complex interconnected signaling pathways, and it was abated by prior CD70 knockdown. These results show that the CD70-CD27 axis modulates T-cell-fibroblast interactions and may be an important regulator of fibrosis and wound healing. Fibroblast CD70 could also be a novel target for specific mechanistically based antifibrosis treatments.


Assuntos
Ligante CD27/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Pulmão/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Humanos , Fibrose Pulmonar Idiopática/metabolismo , Ativação Linfocitária/fisiologia , Transdução de Sinais/fisiologia , Linfócitos T/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Cicatrização/fisiologia
20.
Bratisl Lek Listy ; 121(2): 107-110, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32115961

RESUMO

AIM: Diabetes is one of the most common diseases which can attenuate brain function by destroying hippocampus neurons, while reelin is a largely secreted extracellular matrix glycoprotein in the hippocampus causing synaptic plasticity, promoting postsynaptic structures and maturing neurons. The aim of this study was to assess the effect of exercise, as an external factor for neurogenesis in the brain, on reelin levels and memory improvement in diabetic rats. METHOD: Thirty rats were randomly allocated into three groups; healthy sedentary, diabetic sedentary and diabetic exercise-trained. The experimental group was treadmill-exercised at speed 22 m/min for 1 hour, 5 days per week. Finally, spatial memory of rats was tested and reelin levels were measured. RESULTS: The results showed that short-term exercise improved spatial memory in diabetic rats but had no effect on reelin levels in the hippocampus of diabetic rats. CONCLUSION: Diabetes reduced the spatial memory without altering the reelin levels while exercise improved spatial memory without altering the reelin levels (Fig. 4, Ref. 33).


Assuntos
Moléculas de Adesão Celular Neuronais/metabolismo , Diabetes Mellitus Experimental , Proteínas da Matriz Extracelular/metabolismo , Hipocampo , Proteínas do Tecido Nervoso/metabolismo , Condicionamento Físico Animal , Serina Endopeptidases/metabolismo , Memória Espacial , Animais , Hipocampo/metabolismo , Neurogênese , Plasticidade Neuronal , Ratos
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