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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Análise imunohistoquímica dos proteoglicanossindecan, decorin e biglican na próstata normal e hiperplásica / Immunohistochemical analysis of the proteoglycans sindecan-1, decorin and biglican in the normal and hyperplastic prostate

Bruno Leonardo Marroig de Freitas Ribeiro 30 June 2011 (has links)
Os mecanismos celulares envolvidos na hiperplasia prostática benigna (HPB) não são bem compreendidos e pouco se sabe sobre como os proteoglicanos estão relacionados com esta condição. Neste estudo foi avaliada a expressão de proteoglicanos de superfície celular e do estroma na HPB. As amostras de próstata com HPB foram colhidas de pacientes submetidos à prostatectomia aberta e ressecção transuretral da próstata (RTUP), enquanto as amostras do grupo controle consistiram na zona de transição de próstatas normais de adultos jovens. Foram usados anticorpos primários anti-sindecan-1, anti-biglican e anti-decorin. A imunomarcação foi avaliada determinando-se a área relativa marcada pelo anticorpo, ou usando-se um escore atribuído à intensidade da coloração. Os resultados mostraram que, no grupo controle, a expressão do sindecan-1 foi mínima ou nula. Na HPB, no entanto, a imunomarcação deste proteoglicano foi intensa e localizada principalmente nas células basais do ácino prostático e com menor intensidade na superfície basolateral das células secretoras. Como não houve diferença entre as amostras obtidas através da prostatectomia aberta e da RTUP, esses grupos foram combinados em um único grupo HPB. A área marcada pelo anticorpo anti-sindecan-1 no epitélio das amostras de HPB foi nove vezes maior do que na próstata normal (p<0,001), e não houve correlações significativas entre a marcação do sindecan-1naHPB e o volume da próstata, o PSA ou a idade do paciente. Quanto ao biglican e ao decorin, a marcação foi exclusivamente no estroma, tanto no grupo controle quanto no grupo HPB, e não houve diferença significativa na extensão e intensidade da coloração entre estes dois grupos. Em conclusão, a imunomarcação do sindecan-1 na HPB é intensa e está localizada no epitélio glandular exclusivamente, mas a intensidade não se correlaciona com o tamanho da próstata ou PSA. A expressão do decorin e do biglican, no entanto, não foi alterada na HPB. / The cellular mechanisms involved in benign prostatic hyperplasia (BPH) are not well understood, and little is known about how proteoglycans are affected. Here we investigated the protein expression of stromal and cell surface proteoglycans in BPH. BPH samples were colected from open prostatectomy and transurethral resection of the prostate (TURP), while controls consisted of the transitional zone of normal prostates from young adults. We used primary antibodies against the proteoglycans syndecan-1, biglycan, and decorin. Immunolabeling was evaluated by determining the relative area of staining, or by using a score for staining intensity. The results showed that, in controls, syndecan-1 was mostly negative. In BPH, however, the labeling of this proteoglycan was intense and located mainly in acinar basal cells, but could extended into the secretory cells. As there were no differences in samples from open prostatectomy and TURP, these groups were combined into a BPH group. Syndecan-1 labeling area in the epithelium of BPH samples was nine times greater than that of controls (p<0,001), and there were no significant correlations between syndecan-1 labeling in BPH and prostate volume, PSA, or patients age. Biglycan and decorin labeling were in the stroma exclusively, in control and BPH samples, and there were no significant differences in extent and intensity of the staining between these two groups. In conclusion, syndecan-1 immunolabeling in BPH is prominent and is located in the glandular epithelium exclusively, but intensity does not correlate with prostate size or PSA. Decorin and biglycan labeling, however, were unchanged in BPH.
12

Análise imunohistoquímica dos proteoglicanossindecan, decorin e biglican na próstata normal e hiperplásica / Immunohistochemical analysis of the proteoglycans sindecan-1, decorin and biglican in the normal and hyperplastic prostate

Bruno Leonardo Marroig de Freitas Ribeiro 30 June 2011 (has links)
Os mecanismos celulares envolvidos na hiperplasia prostática benigna (HPB) não são bem compreendidos e pouco se sabe sobre como os proteoglicanos estão relacionados com esta condição. Neste estudo foi avaliada a expressão de proteoglicanos de superfície celular e do estroma na HPB. As amostras de próstata com HPB foram colhidas de pacientes submetidos à prostatectomia aberta e ressecção transuretral da próstata (RTUP), enquanto as amostras do grupo controle consistiram na zona de transição de próstatas normais de adultos jovens. Foram usados anticorpos primários anti-sindecan-1, anti-biglican e anti-decorin. A imunomarcação foi avaliada determinando-se a área relativa marcada pelo anticorpo, ou usando-se um escore atribuído à intensidade da coloração. Os resultados mostraram que, no grupo controle, a expressão do sindecan-1 foi mínima ou nula. Na HPB, no entanto, a imunomarcação deste proteoglicano foi intensa e localizada principalmente nas células basais do ácino prostático e com menor intensidade na superfície basolateral das células secretoras. Como não houve diferença entre as amostras obtidas através da prostatectomia aberta e da RTUP, esses grupos foram combinados em um único grupo HPB. A área marcada pelo anticorpo anti-sindecan-1 no epitélio das amostras de HPB foi nove vezes maior do que na próstata normal (p<0,001), e não houve correlações significativas entre a marcação do sindecan-1naHPB e o volume da próstata, o PSA ou a idade do paciente. Quanto ao biglican e ao decorin, a marcação foi exclusivamente no estroma, tanto no grupo controle quanto no grupo HPB, e não houve diferença significativa na extensão e intensidade da coloração entre estes dois grupos. Em conclusão, a imunomarcação do sindecan-1 na HPB é intensa e está localizada no epitélio glandular exclusivamente, mas a intensidade não se correlaciona com o tamanho da próstata ou PSA. A expressão do decorin e do biglican, no entanto, não foi alterada na HPB. / The cellular mechanisms involved in benign prostatic hyperplasia (BPH) are not well understood, and little is known about how proteoglycans are affected. Here we investigated the protein expression of stromal and cell surface proteoglycans in BPH. BPH samples were colected from open prostatectomy and transurethral resection of the prostate (TURP), while controls consisted of the transitional zone of normal prostates from young adults. We used primary antibodies against the proteoglycans syndecan-1, biglycan, and decorin. Immunolabeling was evaluated by determining the relative area of staining, or by using a score for staining intensity. The results showed that, in controls, syndecan-1 was mostly negative. In BPH, however, the labeling of this proteoglycan was intense and located mainly in acinar basal cells, but could extended into the secretory cells. As there were no differences in samples from open prostatectomy and TURP, these groups were combined into a BPH group. Syndecan-1 labeling area in the epithelium of BPH samples was nine times greater than that of controls (p<0,001), and there were no significant correlations between syndecan-1 labeling in BPH and prostate volume, PSA, or patients age. Biglycan and decorin labeling were in the stroma exclusively, in control and BPH samples, and there were no significant differences in extent and intensity of the staining between these two groups. In conclusion, syndecan-1 immunolabeling in BPH is prominent and is located in the glandular epithelium exclusively, but intensity does not correlate with prostate size or PSA. Decorin and biglycan labeling, however, were unchanged in BPH.
13

Peptídeo AG73, derivado da laminina-111, induz migração, invasão e secreção de proteases em linhagem celular derivada de carcinoma epidermóide oral através de sindecana-1 e integrina b1 / Laminin-111-derived peptide AG73 regulates migration, invasion and protease activity of cell line derived from oral squamous cell carcinoma through syndecan-1 and b1 integrin.

Siqueira, Adriane Sousa de 24 September 2009 (has links)
Carcinona epidermóide é um prevalente tumor de cabeça e pescoço relacionado a altas taxas de mortalidade. Neste trabalho, verificamos se AG73 (RKRLQVQLSIRT, cadeia a1), peptídeo derivado da laminina-111, regula migração, invasão e secreção de protease em células de carcinoma epidermóide oral (OSCC). Cadeia a1 da laminina e MMP9 estão expressas neste tumor in vivo e in vitro. AG73 induziu aumento da taxa migratória de células OSCC em ensaios de ferida e migração, e também estimulou invasão em ensaio em câmaras bipartites com Matrigel. Células OSCC crescidas sobre AG73 exibiram aumento dose-dependente de MMP9, detectado por zimografia. Buscamos receptores de AG73 que regulariam atividade nesta linhagem. Células OSCC crescidas sobre AG73 exibiram colocalização de sindecana-1 e integrina b1, e silenciamento desses receptores com RNA de interferência promoveu diminuição de migração e invasão dependente de AG73 nestas células. Esses resultados sugerem que sindecana-1 e integrina b1, ativados por AG73, podem regular migração, invasão e secreção de MMPs em células OSCC. / Oral squamous cell carcinoma is a prevalent head and neck tumor, related to high mortality rates. Here we studied the role played by AG73 (RKRLQVQLSIRT, a1 chain) on migration, invasion and protease secretion of a cell line (OSCC) from human oral squamous cell carcinoma. Laminin a1 chain and MMP9 are expressed in oral squamous cell carcinoma cells in vivo and in vitro. AG73 increased migratory activity of OSCC cells, as shown by monolayer wound assays and migration assays. This peptide also stimulated cell invasion in chemotaxis chambers coated with Matrigel. OSCC cells cultured on AG73 showed a dose-dependent increase of MMP9 secretion, detected by zymography. We searched for AG73 receptors regulating activities in this cell line. OSCC cells grown on AG73 exhibited colocalization of syndecan-1 and b1 integrin, and siRNA knockdown of these receptors decreased AG73-dependent migration and invasion of OSCC cells. Our results suggest that syndecan-1 and b1 integrin signaling downstream of AG73 regulate migration, invasion and MMP secretion by OSCC cells
14

Adesão e atividade de protease são reguladas pelo peptídeo derivado da laminina AG73, sindecan-1 e integrina 1 em linhagem celular derivada de carcinoma adenóide cístico / Ahesion and protease activity are regulated by the laminin-derived peptide AG73, syndecan-1 and bintegrin in cell line derived from adenoid cystic carcinoma.

Oliveira, Elaine Cyreno 01 October 2009 (has links)
Estudamos indução da atividade de MMP pelo peptídeo da laminina a1 AG73 em linhagem celular (CAC2) de carcinoma adenóide cístico. CAC2 cultivadas em laminina-111 com AG73 geraram espaços pseudocísticos. Inibidor de MMP diminuiu tais espaços, sugerindo ação de MMPs. CAC2 crescidas sobre AG73 mostraram aumento dose-dependente de MMP9. RNAi para MMP9 diminuiu remodelação em cultura 3D. Buscamos receptores de AG73 ligados à atividade de MMP9. CAC2 crescidas sobre AG73 exibiram colocalização de sindecan-1 e integrina b1. RNAi para sindecan-1 ou para integrina b1 geraram, isolados, redução na adesão a AG73 e nas atividades de remodelação e de protease. Duplo RNAi estudou a cooperação entre os receptores e promoveu diminuição na adesão a AG73 e na atividade de MMP. Distinção de receptores foi feita por cromatografia de afinidade e espectrometria de massa, através de colunas de afinidade com AG73 acoplado, que resultou em possíveis receptores, como integrinas b1 e aV. Sugerimos que AG73 regula adesão e secreção de MMP em células CAC2 através de sindecan-1 e integrina b1. / We studied induction of MMP activity by b1-laminin peptide AG73 in adenoid cystic carcinoma cell line (CAC2). Cells grown inside AG73-enriched laminin-111 exhibited pseudocystics spaces. MMP inhibitor decreased those spaces, suggesting MMPs action. Cells grown on AG73 showed a dose-dependent increase of MMP9 secretion. MMP9 siRNAi decreased remodeling in 3D culture. We searched for AG73 receptors regulating MMP9 activity. CAC2 grown on AG73 exhibited colocalization of syndecan-1 and b1 integrin. Syndecan-1 siRNA or siRNA b1 integrin showed reduction in adhesion to AG73 and in remodeling and protease activities. Double-knockdown explored syndecan-1 and 1 integrin cooperation and showed decrease in adhesion to AG73 and in MMP activity. Receptors characterization was made by affinity chromatography followed by mass spectrometry through AG73-affinity columns and showed putative receptors, like b1 and aV integrins. We suggest that AG73 peptide regulates adhesion and MMP secretion in CAC2 cells through syndecan-1 and b1 integrin.
15

The role of Syndecan-1 and extracellular vesicles in breast cancer brain metastasis

Sayyad, Megan R 01 January 2019 (has links)
Breast cancer metastasizes to the brain in 15-30% of all breast cancer cases, and metastasis is the predominant cause of breast cancer-related deaths. Patients with HER2-enriched and triple-negative breast cancers (TNBCs) are more likely to develop brain metastases. While targeted therapies exist for HER2-enriched breast cancers, there are no effective treatments for TNBCs. Thus, a greater understanding of how these cancers spread to the brain is critical. In order to spread to the brain, disseminated breast cancer cells must overcome 2 major steps—crossing the blood-brain barrier (BBB) and survival and successful colonization of the distinctive and mostly cellular brain environment. Here, we report a novel role for breast cancer cell surface receptor, Syndecan-1 (Sdc1), a heparan sulfate proteoglycan, in promoting breast cancer cell transmigration across the BBB. We found that when we silenced Sdc1 expression in a highly metastatic TNBC cell line, MDA-MB-231, these cells exhibited reduced migration across an in vitro BBB model system. Further, in an in vivo experimental model of metastasis, mice injected with MDA-MB-231 Sdc1 KD (knock-down) cells developed less brain metastases than mice injected with control non-silencing (NS1) cells. Conversely, we found that overexpression of Sdc1 in a metastatic triple-negative mouse mammary carcinoma cell line, 4T1, led to an increase in brain metastases compared to empty vector control-treated mice. We predicted that a secreted factor(s) facilitated BBB disruption that allowed for Sdc1-mediated BBB transmigration, and found that silencing Sdc1 led to decreases in the production and/or release of various cytokines and chemokines implicated in BBB permeability and transmigration. In addition to supporting BBB transmigration, through an in vitro tissue section adhesion assay, we found that Sdc1 also facilitates adhesion of breast cancer cells to the brain, and not to the liver or lungs, revealing specificity for the brain. Further, we report that Sdc1 is expressed in 81% of breast cancer patient brain metastases in our tissue microarray study and that patients with TNBC and high Sdc1 expression have shorter disease-free survival based on a study performed using data from The Cancer Genome Atlas. Taken together, we predict that breast cancer cell Sdc1-regulated cytokines and chemokines promote BBB permeability and/or support transmigration to facilitate breast cancer metastasis to the brain. We also provide evidence for breast cancer-secreted extracellular vesicles, namely exosomes, in supporting the formation of a pro-metastatic brain environment. We compared exosomes derived from the metastatic 4T1 mouse mammary carcinoma cell line to a non-metastatic counterpart, the 67NR cell line, to assess their microRNA and protein composition and their effect(s) on recipient astrocytes, known mediators of brain metastasis. We found that there are inherent differences in both the microRNA and protein cargo from the metastatic 4T1 cells compared to the non-metastatic 67NR cells, whereby the metastatic 4T1 cells contained various tumor-promoting microRNAs and proteins, and also contained 4.5-fold more protein than the non-metastatic 67NR cells. Mouse astrocytes treated with the metastatic 4T1 exosomes exhibited a shift towards a pro-metastatic phenotype, characterized by upregulation of pro-inflammatory genes, and genes associated with astrocyte reactivity and cancer, whereby 67NR exosome-treated astrocytes exhibited a response profile that overlapped with untreated controls. Overall, these findings reveal an important role for exosomes in driving changes in the brain microenvironment to create a site conducive for cancer growth. Together, both studies help to elucidate how breast cancer cells can invade and colonize the unique brain environment.
16

ROLE DES MEMBRES DE LA FAMILLE BAFF/APRIL DANS LE MYELOME MULTIPLE : IMPLICATIONS PHYSIOPATHOLOGIQUES ET INTERET THERAPEUTIQUE

Moreaux, Jérome 24 November 2006 (has links) (PDF)
Le myélome multiple (MM) est une néoplasie B caractérisé par l'accumulation d'un clone plasmocytaire dans la moelle osseuse. Cette pathologie demeure incurable d'où la nécessité d'identifier de nouvelles cibles thérapeutiques. C'est notamment dans cette optique que nous avons initié, au sein du laboratoire, un travail de comparaison des profils d'expression génique des plasmocytes tumoraux purifiés de malades avec ceux de plasmocytes normaux et de lymphocytes B, ce qui permettra l'identification de nouvelles voies importantes pour la biologie du MM et donc de nouvelles cibles thérapeutiques potentielles.<br />Par cette approche, nous avons mis en évidence un rôle essentiel des membres de la famille BAFF/APRIL et de leurs récepteurs (BCMA, BAFF-R et TACI) dans la biologie du MM. Les cellules de MM expriment les récepteurs alors que les ligands sont principalement produits par les cellules de l'environnement médullaire. L'utilisation d'un inhibiteur spécifique de BAFF/APRIL a permis de montrer que ces facteurs de croissance sont importants pour la survie et la prolifération des cellules tumorales. TACI apparaît être le récepteur principal pour médier l'effet de BAFF et APRIL dans le MM. Une forte expression de TACI par les cellules de MM est associée à une signature génique de plasmocytes matures alors que les plasmocytes tumoraux présentant une faibles expression de TACI ont une signature génique de plasmablastes proliférants. Nous avons montré que syndecan-1, un protéoglycane à chaînes héparane sulfate joue un rôle essentiel dans la biologie du MM en permettant l'accumulation de fortes concentrations de facteurs de croissance à la surface des cellules. Nous avons identifié que syndecan-1 joue un rôle de corécepteur pour APRIL et TACI supportant ainsi la croissance des cellules de MM. <br />Ces travaux offrent de nouvelles perspectives thérapeutiques pour le MM et ont débouché sur un essai clinique de phase I/II, au CHU de Montpellier, utilisant un inhibiteur de la voie BAFF/APRIL dans le MM.
17

Peptídeo AG73, derivado da laminina-111, induz migração, invasão e secreção de proteases em linhagem celular derivada de carcinoma epidermóide oral através de sindecana-1 e integrina b1 / Laminin-111-derived peptide AG73 regulates migration, invasion and protease activity of cell line derived from oral squamous cell carcinoma through syndecan-1 and b1 integrin.

Adriane Sousa de Siqueira 24 September 2009 (has links)
Carcinona epidermóide é um prevalente tumor de cabeça e pescoço relacionado a altas taxas de mortalidade. Neste trabalho, verificamos se AG73 (RKRLQVQLSIRT, cadeia a1), peptídeo derivado da laminina-111, regula migração, invasão e secreção de protease em células de carcinoma epidermóide oral (OSCC). Cadeia a1 da laminina e MMP9 estão expressas neste tumor in vivo e in vitro. AG73 induziu aumento da taxa migratória de células OSCC em ensaios de ferida e migração, e também estimulou invasão em ensaio em câmaras bipartites com Matrigel. Células OSCC crescidas sobre AG73 exibiram aumento dose-dependente de MMP9, detectado por zimografia. Buscamos receptores de AG73 que regulariam atividade nesta linhagem. Células OSCC crescidas sobre AG73 exibiram colocalização de sindecana-1 e integrina b1, e silenciamento desses receptores com RNA de interferência promoveu diminuição de migração e invasão dependente de AG73 nestas células. Esses resultados sugerem que sindecana-1 e integrina b1, ativados por AG73, podem regular migração, invasão e secreção de MMPs em células OSCC. / Oral squamous cell carcinoma is a prevalent head and neck tumor, related to high mortality rates. Here we studied the role played by AG73 (RKRLQVQLSIRT, a1 chain) on migration, invasion and protease secretion of a cell line (OSCC) from human oral squamous cell carcinoma. Laminin a1 chain and MMP9 are expressed in oral squamous cell carcinoma cells in vivo and in vitro. AG73 increased migratory activity of OSCC cells, as shown by monolayer wound assays and migration assays. This peptide also stimulated cell invasion in chemotaxis chambers coated with Matrigel. OSCC cells cultured on AG73 showed a dose-dependent increase of MMP9 secretion, detected by zymography. We searched for AG73 receptors regulating activities in this cell line. OSCC cells grown on AG73 exhibited colocalization of syndecan-1 and b1 integrin, and siRNA knockdown of these receptors decreased AG73-dependent migration and invasion of OSCC cells. Our results suggest that syndecan-1 and b1 integrin signaling downstream of AG73 regulate migration, invasion and MMP secretion by OSCC cells
18

Adesão e atividade de protease são reguladas pelo peptídeo derivado da laminina AG73, sindecan-1 e integrina 1 em linhagem celular derivada de carcinoma adenóide cístico / Ahesion and protease activity are regulated by the laminin-derived peptide AG73, syndecan-1 and bintegrin in cell line derived from adenoid cystic carcinoma.

Elaine Cyreno Oliveira 01 October 2009 (has links)
Estudamos indução da atividade de MMP pelo peptídeo da laminina a1 AG73 em linhagem celular (CAC2) de carcinoma adenóide cístico. CAC2 cultivadas em laminina-111 com AG73 geraram espaços pseudocísticos. Inibidor de MMP diminuiu tais espaços, sugerindo ação de MMPs. CAC2 crescidas sobre AG73 mostraram aumento dose-dependente de MMP9. RNAi para MMP9 diminuiu remodelação em cultura 3D. Buscamos receptores de AG73 ligados à atividade de MMP9. CAC2 crescidas sobre AG73 exibiram colocalização de sindecan-1 e integrina b1. RNAi para sindecan-1 ou para integrina b1 geraram, isolados, redução na adesão a AG73 e nas atividades de remodelação e de protease. Duplo RNAi estudou a cooperação entre os receptores e promoveu diminuição na adesão a AG73 e na atividade de MMP. Distinção de receptores foi feita por cromatografia de afinidade e espectrometria de massa, através de colunas de afinidade com AG73 acoplado, que resultou em possíveis receptores, como integrinas b1 e aV. Sugerimos que AG73 regula adesão e secreção de MMP em células CAC2 através de sindecan-1 e integrina b1. / We studied induction of MMP activity by b1-laminin peptide AG73 in adenoid cystic carcinoma cell line (CAC2). Cells grown inside AG73-enriched laminin-111 exhibited pseudocystics spaces. MMP inhibitor decreased those spaces, suggesting MMPs action. Cells grown on AG73 showed a dose-dependent increase of MMP9 secretion. MMP9 siRNAi decreased remodeling in 3D culture. We searched for AG73 receptors regulating MMP9 activity. CAC2 grown on AG73 exhibited colocalization of syndecan-1 and b1 integrin. Syndecan-1 siRNA or siRNA b1 integrin showed reduction in adhesion to AG73 and in remodeling and protease activities. Double-knockdown explored syndecan-1 and 1 integrin cooperation and showed decrease in adhesion to AG73 and in MMP activity. Receptors characterization was made by affinity chromatography followed by mass spectrometry through AG73-affinity columns and showed putative receptors, like b1 and aV integrins. We suggest that AG73 peptide regulates adhesion and MMP secretion in CAC2 cells through syndecan-1 and b1 integrin.

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