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2.
PLoS One ; 17(3): e0265765, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35320297

RESUMO

BACKGROUND: Estimations of Lyme disease incidence rates in the United Kingdom vary. There is evidence that this disease is associated with fatigue in its early stage but reports are contradictory as far as long-term fatigue is concerned. METHODS AND FINDINGS: A population-based historical cohort study was conducted on patients treated in general practices contributing to IQVIA Medical Research Data: 2,130 patients with a first diagnosis of Lyme disease between 2000 and 2018 and 8,510 randomly-sampled patients matched by age, sex, and general practice, followed-up for a median time of 3 years and 8 months. Main outcome measure was time to consultation for (1) any fatigue-related symptoms or diagnosis; or (2) myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Adjusted hazard ratios (HRs) were estimated from Cox models. Average incidence rate for Lyme disease across the UK was 5.18 per 100,000 person-years, increasing from 2.55 in 2000 to 9.33 in 2018. In total, 929 events of any types of fatigue were observed, leading to an incidence rate of 307.90 per 10,000 person-years in the Lyme cohort (282 events) and 165.60 in the comparator cohort (647 events). Effect of Lyme disease on any subsequent fatigue varied by index season: adjusted HRs were the highest in autumn and winter with 3.14 (95%CI: 1.92-5.13) and 2.23 (1.21-4.11), respectively. For ME/CFS, 17 events were observed in total. Incidence rates were 11.76 per 10,000 person-years in Lyme patients (12 events) and 1.20 in comparators (5 events), corresponding to an adjusted HR of 16.95 (5.17-55.60). Effects were attenuated 6 months after diagnosis but still clearly visible. CONCLUSIONS: UK primary care records provided strong evidence that Lyme disease was associated with subsequent fatigue and ME/CFS. Albeit weaker on the long-term, these effects persisted beyond 6 months, suggesting patients and healthcare providers should remain alert to fatigue symptoms months to years following Lyme disease diagnosis.


Assuntos
Síndrome de Fadiga Crônica , Doença de Lyme , Pré-Escolar , Estudos de Coortes , Síndrome de Fadiga Crônica/diagnóstico , Humanos , Incidência , Doença de Lyme/complicações , Doença de Lyme/diagnóstico , Doença de Lyme/epidemiologia , Reino Unido/epidemiologia
3.
PLoS One ; 10(12): e0145369, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26694869

RESUMO

Basal cell carcinoma (BCC) is the commonest tumor in human. About 70% sporadic BCCs bear somatic mutations in the PATCHED1 tumor suppressor gene which encodes the receptor for the Sonic Hedgehog morphogen (SHH). PATCHED1 germinal mutations are associated with the dominant Nevoid Basal Cell Carcinoma Syndrome (NBCCS), a major hallmark of which is a high susceptibility to BCCs. Although the vast majority of sporadic BCCs arises exclusively in sun exposed skin areas, 40 to 50% BCCs from NBCCS patients develop in non photo-exposed skin. Since overwhelming evidences indicate that microenvironment may both be modified by- and influence the- epithelial tumor, we hypothesized that NBCCS fibroblasts could contribute to BCCs in NBCCS patients, notably those developing in non photo-exposed skin areas. The functional impact of NBCCS fibroblasts was then assessed in organotypic skin cultures with control keratinocytes. Onset of epidermal differentiation was delayed in the presence of primary NBCCS fibroblasts. Unexpectedly, keratinocyte proliferation was severely reduced and showed high levels of nuclear P53 in both organotypic skin cultures and in fibroblast-led conditioning experiments. However, in spite of increased levels of senescence associated ß-galactosidase activity in keratinocytes cultured in the presence of medium conditioned by NBCCS fibroblasts, we failed to observe activation of P16 and P21 and then of bona fide features of senescence. Constitutive extinction of P53 in WT keratinocytes resulted in an invasive phenotype in the presence of NBCCS fibroblasts. Finally, we found that expression of SHH was limited to fibroblasts but was dependent on the presence of keratinocytes. Inhibition of SHH binding resulted in improved epidermal morphogenesis. Altogether, these data suggest that the repertoire of diffusible factors (including SHH) expressed by primary NBCCS fibroblasts generate a stress affecting keratinocytes behavior and epidermal homeostasis. Our findings suggest that defects in dermo/epidermal interactions could contribute to BCC susceptibility in NBCCS patients.


Assuntos
Síndrome do Nevo Basocelular/patologia , Carcinoma Basocelular/patologia , Fibroblastos/citologia , Receptores de Superfície Celular/genética , Neoplasias Cutâneas/patologia , Microambiente Tumoral , Síndrome do Nevo Basocelular/genética , Síndrome do Nevo Basocelular/metabolismo , Carcinoma Basocelular/etiologia , Carcinoma Basocelular/genética , Carcinoma Basocelular/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Meios de Cultivo Condicionados/farmacologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Mutação , Técnicas de Cultura de Órgãos , Receptores Patched , Receptor Patched-1 , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Proteína Supressora de Tumor p53/metabolismo
4.
BMC Clin Pathol ; 12: 14, 2012 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-22947174

RESUMO

BACKGROUND: Tenascins are large glycoproteins found in the extracellular matrix of many embryonic and adult tissues. Tenascin-C is a well-studied biomarker known for its high overexpression in the stroma of most solid cancers. Tenascin-W, the least studied member of the family, is highly expressed in the stroma of colon and breast tumors and in gliomas, but not in the corresponding normal tissues. Other solid tumors have not been analyzed. The present study was undertaken to determine whether tenascin-W could serve as a cancer-specific extracellular matrix protein in a broad range of solid tumors. METHODS: We analyzed the expression of tenascin-W and tenascin-C by immunoblotting and by immunohistochemistry on multiple frozen tissue microarrays of carcinomas of the pancreas, kidney and lung as well as melanomas and compared them to healthy tissues. RESULTS: From all healthy adult organs tested, only liver and spleen showed detectable levels of tenascin-W, suggesting that tenascin-W is absent from most human adult organs under normal, non-pathological conditions. In contrast, tenascin-W was detectable in the majority of melanomas and their metastases, as well as in pancreas, kidney, and lung carcinomas. Comparing lung tumor samples and matching control tissues for each patient revealed a clear overexpression of tenascin-W in tumor tissues. Although the number of samples examined is too small to draw statistically significant conclusions, there seems to be a tendency for increased tenascin-W expression in higher grade tumors. Interestingly, in most tumor types, tenascin-W is also expressed in close proximity to blood vessels, as shown by CD31 co-staining of the samples. CONCLUSIONS: The present study extends the tumor biomarker potential of tenascin-W to a broad range of solid tumors and shows its accessibility from the blood stream for potential therapeutic strategies.

5.
Int J Biol Sci ; 8(2): 187-94, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22211116

RESUMO

Tenascins are extracellular matrix glycoproteins associated with cell motility, proliferation and differentiation. Tenascin-C inhibits cell spreading by binding to fibronectin; tenascin-R and tenascin-X also have anti-adhesive properties in vitro. Here we have studied the adhesion modulating properties of the most recently characterized tenascin, tenascin-W. C2C12 cells, a murine myoblast cell line, will form broad lamellipodia with stress fibers and focal adhesion complexes after culture on fibronectin. In contrast, C2C12 cells cultured on tenascin-W fail to spread and form stress fibers or focal adhesion complexes, and instead acquire a multipolar shape with short, actin-tipped pseudopodia. The same stellate morphology is observed when C2C12 cells are cultured on a mixture of fibronectin and tenascin-W, or on fibronectin in the presence of soluble tenascin-W. Tenascin-W combined with fibronectin also inhibits the spreading of mouse embryo fibroblasts when compared with cells cultured on fibronectin alone. The similarity between the adhesion modulating effects of tenascin-W and tenascin-C in vitro led us to study the possibility of tenascin-W compensating for tenascin-C in tenascin-C knockout mice, especially during epidermal wound healing. Dermal fibroblasts harvested from a tenascin-C knockout mouse express tenascin-W, but dermal fibroblasts taken from a wild type mouse do not. However, there is no upregulation of tenascin-W in the dermis of tenascin-C knockout mice, or in the granulation tissue of skin wounds in tenascin-C knockout animals. Similarly, tenascin-X is not upregulated in early wound granulation tissue in the tenascin-C knockout mice. Thus, tenascin-W is able to inhibit cell spreading in vitro and it is upregulated in dermal fibroblasts taken from the tenascin-C knockout mouse, but neither it nor tenascin-X are likely to compensate for missing tenascin-C during wound healing.


Assuntos
Adesão Celular , Tenascina/fisiologia , Actinas/metabolismo , Actinas/fisiologia , Animais , Técnicas de Cultura de Células , Linhagem Celular , Movimento Celular , Células Cultivadas , Fibronectinas/metabolismo , Fibronectinas/farmacologia , Fibronectinas/fisiologia , Regulação da Expressão Gênica , Técnicas de Inativação de Genes , Camundongos , Pseudópodes/fisiologia , Pseudópodes/ultraestrutura , Tenascina/genética , Tenascina/metabolismo , Tenascina/farmacologia , Cicatrização/genética
6.
J Cell Mol Med ; 16(1): 32-40, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21692981

RESUMO

Tenascins are large glycoproteins found in embryonic and adult extracellular matrices. Of the four family members, two have been shown to be overexpressed in the microenvironment of solid tumours: tenascin-C and tenascin-W. The regular presence of these proteins in tumours suggests a role in tumourigenesis, which has been investigated intensively for tenascin-C and recently for tenascin-W as well. In this review, we follow a malignant cell starting from its birth through its potential metastatic journey and describe how tenascin-C and tenascin-W contribute to these successive steps of tumourigenesis. We consider the importance of the mechanical aspect in tenascin signalling. Furthermore, we discuss studies describing tenascin-C as an important component of stem cell niches and present examples reporting its role in cancer therapy resistance.


Assuntos
Transformação Celular Neoplásica , Neoplasias/patologia , Neoplasias/fisiopatologia , Isoformas de Proteínas/metabolismo , Tenascina/metabolismo , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal/fisiologia , Humanos , Metástase Neoplásica/patologia , Neovascularização Patológica , Transdução de Sinais/fisiologia , Nicho de Células-Tronco
7.
FEBS Lett ; 585(6): 913-20, 2011 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-21354146

RESUMO

We explored novel functions of tenascin-C by comparing mouse embryonic fibroblasts (MEFs) proficient or deficient in tenascin-C expression. Transcript profiling analysis identified tissue plasminogen activator (tPA) as the most consistently over-expressed gene in all tenascin-C deficient MEFs. This was confirmed by real-time PCR as well as by protein expression analysis. In agreement with these observations, tenascin-C deficient MEFs had an increased capacity to digest fibrin in situ. Consistently, tenascin-C expression in vivo was found to correlate with fibrin deposition in several diseases associated with tenascin-C overexpression such as fibrosis, asthma and cancer. In conclusion, the present study suggests a new role of tenascin-C as a regulator of the fibrinolytic system.


Assuntos
Fibrina/metabolismo , Fibroblastos/metabolismo , Tenascina/metabolismo , Ativador de Plasminogênio Tecidual/metabolismo , Animais , Western Blotting , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Regulação para Baixo , Embrião de Mamíferos/citologia , Feminino , Fibrinolisina/metabolismo , Fibroblastos/citologia , Perfilação da Expressão Gênica , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Imuno-Histoquímica , Pneumopatias/metabolismo , Pneumopatias/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Análise de Sequência com Séries de Oligonucleotídeos , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tenascina/genética , Ativador de Plasminogênio Tecidual/genética
8.
Matrix Biol ; 30(3): 225-33, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21349332

RESUMO

Tenascin-C is an extracellular matrix protein over-expressed in a large variety of cancers. In the present study, we aimed at identifying new interactors of tenascin-C by purifying secreted proteins on a tenascin-C affinity column. Analysis of eluates by mass spectrometry revealed phosphoglycerate kinase 1, clusterin, fibronectin, SPARC-related modular calcium-binding protein 1 (SMOC1) and nidogen-2 as potential interactors of tenascin-C. The interaction between tenascin-C and SMOC1 was confirmed by co-immunoprecipitation and further analyzed by Surface Plasmon Resonance Spectroscopy, which revealed an apparent dissociation constant (K(D)) value of 2.59∗10(-9)M. Further analyses showed that this binding is reduced in the presence of EDTA. To investigate whether SMOC1 itself could be over-expressed in the context of tumorigenesis, we analyzed data of two independent RNA profiling studies and found that mRNA levels of SMOC1 are significantly increased in oligodendrogliomas compared to control brain samples. In support of these data, western blot analysis of protein extracts from 12 oligodendrogliomas, 4 astrocytomas and 13 glioblastomas revealed elevated levels compared to healthy brain extract. Interestingly, cell migration experiments revealed that SMOC1 can counteract the chemo-attractive effect of tenascin-C on U87 glioma cells. The present study thus identified SMOC1 as a new cancer-associated protein capable of interacting with tenascin-C in vitro.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Osteonectina/metabolismo , Tenascina/metabolismo , Regulação para Cima , Adulto , Idoso , Neoplasias Encefálicas/patologia , Estudos de Casos e Controles , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , Humanos , Imunoprecipitação , Pessoa de Meia-Idade , Ligação Proteica , Ressonância de Plasmônio de Superfície
9.
Dev Growth Differ ; 52(9): 747-55, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21158754

RESUMO

ATAD2 is an E2F target gene that is highly expressed in gastrointestinal and breast carcinomas. Here we characterize a related gene product, ATAD2B. Both genes are evolutionarily conserved, with orthologues present in all eukaryotic genomes examined. Human ATAD2B shows a high degree of similarity to ATAD2. Both contain an AAA domain and a bromodomain with amino acid sequences sharing 97% and 74% identity, respectively. The expression of ATAD2B was studied in the chicken embryo using a polyclonal antibody raised against a recombinant fragment of human ATAD2B. Immunohistochemistry revealed transient nuclear expression in subpopulations of developing neurons. The transient nature of the expression was confirmed by immunoblotting homogenates of the developing telencephalon. Cell fractionation was used to confirm the nuclear localization of ATAD2B in the developing nervous system: anti-ATAD2B recognizes a smaller band (approximately 160 kDa) in the nuclear fraction and a larger band (approximately 300 kDa) in the membrane fraction, suggesting that posttranslational processing of ATAD2B may regulate its transport to the nucleus. The expression of ATAD2B was also studied in human tumors. Oncomine and immunohistochemistry reveal ATAD2B expression in glioblastoma and oligodendroglioma; ATAD2B immunostaining was also elevated in human breast carcinoma. In tumors ATAD2B appears to be cytoplasmic or membrane bound, and not nuclear. Our observations suggest that ATAD2B may play a role in neuronal differentiation and tumor progression.


Assuntos
Adenosina Trifosfatases/genética , Diferenciação Celular/genética , Transformação Celular Neoplásica/genética , Neoplasias/genética , Neoplasias/patologia , Neurônios/citologia , Proteínas Nucleares/genética , Filogenia , ATPases Associadas a Diversas Atividades Celulares , Animais , Embrião de Galinha , Humanos , Neurônios/metabolismo , Proteínas Nucleares/metabolismo
10.
Int J Biochem Cell Biol ; 42(9): 1412-5, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20541035

RESUMO

Tenascin-W was the last member of a family of four large extracellular matrix glycoproteins to be discovered. The original member of the tenascin family, tenascin-C, has been widely studied due to its association with asthma, fibrosis, infection, inflammation and cancer. Recent studies report multiple common features between tenascin-W and tenascin-C in terms of structure, expression and function, especially in the context of tumorigenesis. Furthermore, specific functions for tenascin-W in osteogenesis have been revealed. This review presents an update on our current knowledge concerning tenascin-W and discusses potential medical applications of this cancer-enriched extracellular matrix protein.


Assuntos
Proteínas da Matriz Extracelular/metabolismo , Neoplasias/metabolismo , Osteogênese/fisiologia , Tenascina/metabolismo , Animais , Proteínas da Matriz Extracelular/genética , Humanos , Neoplasias/genética , Osteogênese/genética , Tenascina/química , Tenascina/genética
11.
FASEB J ; 24(3): 778-87, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19884327

RESUMO

The microenvironment hosting a tumor actively participates in regulating tumor cell proliferation, migration, and invasion. Among the extracellular matrix proteins enriched in the stroma of carcinomas are the tenascin family members tenascin-C and tenascin-W. Whereas tenascin-C overexpression in gliomas is known to correlate with poor prognosis, the status of tenascin-W in brain tumors has not been investigated so far. In the present study, we analyzed protein levels of tenascin-W in 38 human gliomas and found expression of tenascin-W in 80% of the tumor samples, whereas no tenascin-W could be detected in control, nontumoral brain tissues. Double immunohistochemical staining of tenascin-W and von Willebrand factor revealed that tenascin-W is localized around blood vessels, exclusively in tumor samples. In vitro, the presence of tenascin-W increased the proportion of elongated human umbilical vein endothelial cells (HUVECs) and augmented the mean speed of cell migration. Furthermore, tenascin-W triggered sprouting of HUVEC spheroids to a similar extent as the proangiogenic factor tenascin-C. In conclusion, our study identifies tenascin-W as a candidate biomarker for brain tumor angiogenesis that could be used as a molecular target for therapy irrespective of the glioma subtype.-Martina, E., Degen, M., Rüegg, C., Merlo, A., Lino, M. M., Chiquet-Ehrismann, R., Brellier, F. Tenascin-W is a specific marker of glioma-associated blood vessels and stimulates angiogenesis in vitro.


Assuntos
Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/farmacologia , Vasos Sanguíneos/metabolismo , Glioma/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Tenascina/metabolismo , Tenascina/farmacologia , Western Blotting , Crescimento Celular/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Imunofluorescência , Humanos , Técnicas In Vitro , Esferoides Celulares/efeitos dos fármacos , Veias Umbilicais/citologia
12.
Matrix Biol ; 29(1): 31-42, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19748582

RESUMO

The metalloprotease meprin has been implicated in tissue remodelling due to its capability to degrade extracellular matrix components. Here, we investigated the susceptibility of tenascin-C to cleavage by meprinbeta and the functional properties of its proteolytic fragments. A set of monoclonal antibodies against chicken and human tenascin-C allowed the mapping of proteolytic fragments generated by meprinbeta. In chicken tenascin-C, meprinbeta processed all three major splicing variants by removal of 10kDa N-terminal and 38kDa C-terminal peptides, leaving a large central part of subunits intact. A similar cleavage pattern was found for large human tenascin-C variant where two N-terminal peptides (10 or 15kDa) and two C-terminal fragments (40 and 55kDa) were removed from the intact subunit. N-terminal sequencing revealed the exact amino acid positions of cleavage sites. In both chicken and human tenascin-C N-terminal cleavages occurred just before and/or after the heptad repeats involved in subunit oligomerization. In the human protein, an additional cleavage site was identified in the alternative fibronectin type III repeat D. Whereas all these sites are known to be attacked by several other proteases, a unique cleavage by meprinbeta was located to the 7th constant fibronectin type III repeat in both chicken and human tenascin-C, thereby removing the C-terminal domain involved in its anti-adhesive activity. In cell adhesion assays meprinbeta-digested human tenascin-C was not able to interfere with fibronectin-mediated cell spreading, confirming cleavage in the anti-adhesive domain. Whereas the expression of meprinbeta and tenascin-C does not overlap in normal colon tissue, inflamed lesions of the mucosa from patients with Crohn's disease exhibited many meprinbeta-positive leukocytes in regions where tenascin-C was strongly induced. Our data indicate that, at least under pathological conditions, meprinbeta might attack specific functional sites in tenascin-C that are important for its oligomerization and anti-adhesive activity.


Assuntos
Adesão Celular/fisiologia , Metaloendopeptidases/metabolismo , Isoformas de Proteínas/metabolismo , Tenascina/metabolismo , Processamento Alternativo , Sequência de Aminoácidos , Animais , Linhagem Celular , Galinhas , Colo/metabolismo , Colo/patologia , Doença de Crohn/metabolismo , Doença de Crohn/patologia , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Fibronectinas/metabolismo , Humanos , Metaloendopeptidases/genética , Dados de Sequência Molecular , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Isoformas de Proteínas/genética , Multimerização Proteica , Estrutura Quaternária de Proteína , Subunidades Proteicas/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Tenascina/química , Tenascina/genética
13.
PLoS One ; 4(3): e4818, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19287498

RESUMO

Gorlin's or nevoid basal cell carcinoma syndrome (NBCCS) causes predisposition to basal cell carcinoma (BCC), the commonest cancer in adult human. Mutations in the tumor suppressor gene PTCH1 are responsible for this autosomal dominant syndrome. In NBCCS patients, as in the general population, ultraviolet exposure is a major risk factor for BCC development. However these patients also develop BCCs in sun-protected areas of the skin, suggesting the existence of other mechanisms for BCC predisposition in NBCCS patients. As increasing evidence supports the idea that the stroma influences carcinoma development, we hypothesized that NBCCS fibroblasts could facilitate BCC occurence of the patients. WT (n = 3) and NBCCS fibroblasts bearing either nonsense (n = 3) or missense (n = 3) PTCH1 mutations were cultured in dermal equivalents made of a collagen matrix and their transcriptomes were compared by whole genome microarray analyses. Strikingly, NBCCS fibroblasts over-expressed mRNAs encoding pro-tumoral factors such as Matrix Metalloproteinases 1 and 3 and tenascin C. They also over-expressed mRNA of pro-proliferative diffusible factors such as fibroblast growth factor 7 and the stromal cell-derived factor 1 alpha, known for its expression in carcinoma associated fibroblasts. These data indicate that the PTCH1(+/-) genotype of healthy NBCCS fibroblasts results in phenotypic traits highly reminiscent of those of BCC associated fibroblasts, a clue to the yet mysterious proneness to non photo-exposed BCCs in NBCCS patients.


Assuntos
Síndrome do Nevo Basocelular/patologia , Carcinoma Basocelular/patologia , Receptores de Superfície Celular/genética , Neoplasias Cutâneas/patologia , Pele/patologia , Membrana Basal/metabolismo , Citocinas/metabolismo , Fibroblastos/enzimologia , Fibroblastos/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Metaloproteinases da Matriz/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Receptores Patched , Receptor Patched-1 , RNA Mensageiro/genética , Pele/enzimologia , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
14.
Int J Cancer ; 122(11): 2454-61, 2008 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-18306355

RESUMO

Tenascins are extracellular matrix proteins present during the development of organisms as well as in pathological conditions. Tenascin-W, the fourth and last member of the tenascin family remains the least well-characterized one. Our study aimed to evaluate the potential significance of tenascin-W as cancer biomarker by monitoring its presence in the serum of colorectal and breast cancer patients and its expression in colorectal tumor tissues. To measure serum tenascin-W levels, a sensitive sandwich-ELISA was established. Mean tenascin-W concentration in sera of patients with nonmetastatic colorectal cancer at time of diagnosis was highly increased compared to that of healthy volunteers. A similar tendency was observed for tenascin-C in the same patient cohort. However, the increase was much more striking for tenascin-W. We also detected elevated tenascin-W levels in sera of breast cancer patients. Furthermore, we could show a prominent expression of tenascin-W in extracts from colorectal tumor tissues by immunoblot analysis, whereas tenascin-W was not detectable in the corresponding normal colon mucosa. To confirm the western blot results, we performed immunohistochemistry of frozen sections of the same patients as well as of an additional, independently chosen collection of colorectal cancer tissues. In all cases, similarly to tenascin-C, tenascin-W was detected in the tumor stroma. Our results reveal a clear association between elevated levels of tenascin-W and the presence of cancer. These results warrant further studies to evaluate the potential value of serum and tissue tenascin-W levels as diagnostic, prognostic or monitoring biomarker in colorectal, breast and possibly other solid cancers.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , Neoplasias Colorretais/sangue , Tenascina/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Western Blotting , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Neoplasias Colorretais/química , Neoplasias Colorretais/patologia , Diagnóstico Diferencial , Ensaio de Imunoadsorção Enzimática , Feminino , Secções Congeladas , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Mucosa Intestinal/química , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Valor Preditivo dos Testes , Prognóstico , Sensibilidade e Especificidade , Tenascina/análise , Regulação para Cima
15.
Cancer Res ; 67(19): 9169-79, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17909022

RESUMO

This is the first report about human tenascin-W, the fourth and final member of the extracellular matrix protein family of tenascins. Sixty-three human breast tumor extracts were analyzed by Western blotting for the presence of tenascin-W and compared with tenascin-C, an established marker of tumor stroma. Interestingly, we found tenascin-W expression in the majority of the tumor tissues, but no detectable expression in the normal mammary parenchyma. Eighty-one percent of the breast tumor samples were tenascin-W positive and 86% showed expression of tenascin-C. However, tenascin-W and tenascin-C amounts varied greatly between tumors and some contained either tenascin-W or tenascin-C exclusively, indicating independent mechanisms regulating their expression. Although there was no difference between high- or low-grade tumors with respect to the presence of tenascin-C, tenascin-W was more prominent in low-grade tumors. For 42 of the breast cancer tissues, a frozen tumor microarray was available to confirm the Western blot data by immunohistochemistry. Similar to tenascin-C, tenascin-W was detected in the tumor stroma. Fibroblasts adhered to tenascin-W in a beta(1) integrin-dependent manner and spread with a distinctive morphology under conditions where they remained round on tenascin-C. CHOB2 cells expressing alpha(v)beta(1) or alpha4beta(1) integrins were able to spread on tenascin-W. Furthermore, addition of tenascin-W to the culture medium increased migration of breast cancer cells toward a fibronectin substratum in vitro. These data imply that tenascin-W expression in the activated tumor stroma facilitates tumorigenesis by supporting the migratory behavior of breast cancer cells.


Assuntos
Biomarcadores Tumorais/biossíntese , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Tenascina/biossíntese , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Adesão Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibronectinas/metabolismo , Humanos , Imuno-Histoquímica , Estadiamento de Neoplasias , Células Estromais/patologia , Tenascina/genética
16.
Development ; 134(9): 1745-54, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17409116

RESUMO

Development of the postnatal cerebellum relies on the tight regulation of cell number by morphogens that control the balance between cell proliferation, survival and differentiation. Here, we analyze the role of the serine-protease inhibitor protease nexin 1 (PN-1; SERPINE2) in the proliferation and differentiation of cerebellar granular neuron precursors (CGNPs) via the modulation of their main mitogenic factor, sonic hedgehog (SHH). Our studies show that PN-1 interacts with low-density lipoprotein receptor-related proteins (LRPs) to antagonize SHH-induced CGNP proliferation and that it inhibits the activity of the SHH transcriptional target GLI1. The binding of PN-1 to LRPs interferes with SHH-induced cyclin D1 expression. CGNPs isolated from Pn-1-deficient mice exhibit enhanced basal proliferation rates due to overactivation of the SHH pathway and show higher sensitivity to exogenous SHH. In vivo, the Pn-1 deficiency alters the expression of SHH target genes. In addition, the onset of CGNP differentiation is delayed, which results in an enlarged outer external granular layer. Furthermore, the Pn-1 deficiency leads to an overproduction of CGNPs and to enlargement of the internal granular layer in a subset of cerebellar lobes during late development and adulthood. We propose that PN-1 contributes to shaping the cerebellum by promoting cell cycle exit.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Cerebelo/crescimento & desenvolvimento , Proteínas Hedgehog/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores de LDL/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Células Cultivadas , Cerebelo/metabolismo , Feminino , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nexinas de Proteases , Receptores de Superfície Celular/genética , Transdução de Sinais
17.
Cancer Res ; 64(8): 2699-704, 2004 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15087382

RESUMO

Basal cell carcinoma (BCC) is one of the major types of skin cancer arising from keratinocytes. The SONIC HEDGEHOG pathway is deregulated in 100% of sporadic BCCs, as indicated by the overexpression of PATCHED, whose product encodes the receptor of SONIC HEDGEHOG, in 100% of analyzed BCCs. Reverse transcription-PCR analysis revealed that exposure to UVB irradiation, which is a risk factor known to contribute to BCC development, induces a strong and sharp decrease of PATCHED mRNA level both in vitro and ex vivo. Transcription of a reporter gene driven by the 4.4-kb 5'-regulatory region of the human PATCHED gene was shown to be down-regulated after UVB irradiation. Furthermore, overexpression of c-JUN, a member of the activator protein (AP)-1 family, induced repression of the PATCHED promoter. The role of AP-1 in UVB-induced PATCHED repression was confirmed in mouse embryonic fibroblasts knocked out for c-JUN NH(2)-terminal protein kinase. This study thus provides the first evidence of UV-induced down-regulation at the transcriptional level of the BCC-associated tumor suppressor PATCHED relying on activation of the AP-1 oncogenic pathway.


Assuntos
Queratinócitos/fisiologia , Queratinócitos/efeitos da radiação , Proteínas de Membrana/genética , Fator de Transcrição AP-1/efeitos da radiação , Ativação Transcricional/efeitos da radiação , Adulto , Diferenciação Celular/fisiologia , Células Cultivadas , Pré-Escolar , Relação Dose-Resposta à Radiação , Células Epidérmicas , Epiderme/fisiologia , Epiderme/efeitos da radiação , Humanos , Queratinócitos/metabolismo , Proteínas de Membrana/biossíntese , Proteínas de Membrana/efeitos da radiação , Receptores Patched , Regiões Promotoras Genéticas , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores de Superfície Celular , Fator de Transcrição AP-1/fisiologia , Transcrição Gênica/efeitos da radiação
18.
Hum Gene Ther ; 14(10): 983-96, 2003 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12869216

RESUMO

Xeroderma pigmentosum (XP) is a rare photosensitive and cancer-prone syndrome transmitted as an autosomal recessive trait. Most cancers developed by XP patients are basal and squamous cell carcinoma strikingly restricted to sun-exposed parts of the skin. Cells from patients with classic XP are deficient in nucleotide excision repair, a versatile biochemical mechanism for removal of ultraviolet-induced DNA lesions. Among the seven classic XP complementation groups known to date (XP-A to XP-G), XP-C is the most common one in Europe and North Africa and XP-C patients remain free of neurologic problems often seen in other XP complementation groups. This has prompted us to undertake genetic correction of XP-C fibroblasts and particularly keratinocytes, which are the most relevant cells in relation to skin cancer and have proven recently to be capable of reconstructing XP-C skin in vitro. In this study, we demonstrate that DNA repair capacity, cell survival properties, and transition from proliferative to abortive keratinocyte colonies toward UVB irradiation can be fully recovered in keratinocytes from patients with XPC transduced with a retroviral vector stably driving the expression of the wild-type XPC protein. In addition, we show that in the absence of UV, XP-C keratinocytes exhibit intrinsic cell cycle abnormalities, and beta(1)-integrin overexpression, defects that are also both fully reversed after genetic correction. Together with full correction of the defects in XP-C corrected keratinocytes, in vitro reconstruction of skin from these cells open a rational perspective to XP tissue therapy.


Assuntos
Reparo do DNA , Proteínas de Ligação a DNA/genética , Queratinócitos/patologia , Xeroderma Pigmentoso/genética , Divisão Celular , Sobrevivência Celular , Células Cultivadas , Criança , Pré-Escolar , Proteínas de Ligação a DNA/metabolismo , Teste de Complementação Genética , Humanos , Integrina beta1/metabolismo , Queratinócitos/metabolismo , Vírus da Leucemia Murina de Moloney/genética , Pele/anatomia & histologia , Transdução Genética
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