La lombalgie liée à la dégénérescence du disque intervertébral (DIV) est un problème majeur de santé publique touchant une large proportion de nos populations vieillissantes. Actuellement, la prise en charge de cette maladie est essentiellement symptomatique mais grâce à de récentes découvertes, les processus de dégénérescence discale sont aujourd'hui mieux compris. Ces nouvelles connaissances permettent d'envisager de nouvelles stratégies thérapeutiques. Parmi ces stratégies et afin de répondre aux stades précoces de cette maladie, une attention particulière est portée sur les stratégies impliquant l’injection intradiscale de facteurs de croissance tels que le GDF-5 ou le TGF-β1, ciblant les processus de dégénérescence du DIV. En dépit de résultats encourageants concernant la sécurité d’utilisation et la tolérance clinique de ces facteurs de croissance, leur efficacité clinique doit encore être amélioré. Pour cela, l’utilisation de biomateriaux permettant une libération prolongée et la protection des facteurs de croissance, présente un intérêt majeur. Ce travail de thèse a donc pour objectif le développement de systèmes à libération prolongée de ces deux facteurs de croissance. Pour ce faire, deux biomatériaux ont été étudiés : les nanofibres de silice et les microbilles de pullulane. Pour ces deux matériaux, leurs synthèses et caractérisations ont été réalisées avant de s'intéresser à leur potentiel d'adsorption et de libération des facteurs de croissance. Les résultats obtenus sont tres encourageants puisqu’ils montrent une libération prolongée jusqu’a 28 jours in vitro avec un maintien de l’activité biologique des facteurs de croissance libérés. L’ensemble des données de cette thèse suggère le potentiel prometteur des systèmes présentés pour le développement de stratégies innovantes pour la médecine régénératrice DIV. / Low back pain caused by the intervertebral disc (IVD) degeneration is a major health concern affecting a large proportion of our aging populations. While current treatments of this disease are mainly symptomatic, recent discoveries have allowed a better understanding of the degenerative processes and new therapeutic strategies have been envisioned. Among these strategies, there is a growing interest for approaches aiming a tackling early stages of this disease, involving the intradiscal injection of growth factors such as GDF-5 or TGF-β1, able to target IVD degenerative processes. However, despite encouraging results regarding the safety and clinical tolerance of these growth factors, their clinical efficacy has to be further improved. To this end, the use of biomaterials allowing the sustained release and the protection of growth factors is of particular interest. The objective of this thesis is thus to develop systems able to deliver these two growth factors in a long period of time. Therefore, two biomaterials were studied: silica nanofibers and pullulan microbeads. For both materials, their syntheses and characterizations were studied, as well as their potential use for growth factors adsorption and release. Promising results were obtained demonstrating a sustained release for up to 28 days in vitro, while maintaining the released growth factors biological activity. Altogether, these data suggest that these newly designed systems may be promising candidates for the development of innovative strategies for the IVD regenerative medicine.

VASCONCELOS, G. L. Efeitos do fator de crescimento e diferenciação-9 e do hormônio folículo estimulante sobre o desenvolvimento in vitro de folículos pré-antrais bovinos. 2012. 93 f. Dissertação (Mestrado em Biotecnologia) - Campus de Sobral, Universidade Federal do Ceará, Sobral, 2012. / Submitted by Djeanne Costa (djeannecosta@gmail.com) on 2016-06-29T14:29:51Z No. of bitstreams: 1 2012_dis_glvasconcelos.pdf: 1200212 bytes, checksum: a407d9f70fa82b6a4fd6ccd68998217d (MD5) / Approved for entry into archive by Djeanne Costa (djeannecosta@gmail.com) on 2016-06-29T14:30:06Z (GMT) No. of bitstreams: 1 2012_dis_glvasconcelos.pdf: 1200212 bytes, checksum: a407d9f70fa82b6a4fd6ccd68998217d (MD5) / Made available in DSpace on 2016-06-29T14:30:06Z (GMT). No. of bitstreams: 1 2012_dis_glvasconcelos.pdf: 1200212 bytes, checksum: a407d9f70fa82b6a4fd6ccd68998217d (MD5) Previous issue date: 2012 / The results show that after 6 days of culture, FSH alone or associated with GDF-9 increased follicular diameter in relation to control medium. Moreover, after 12 days of culture, FSH promoted an increase in follicular diameter, while the association of FSH with GDF-9 significantly reduced follicular diameter when compared with follicles cultured in MEM plus FSH. Furthermore, FSH and GDF-9 increased the antrum formation after 12 days of culture (P<0.05). Despite GDF-9 had significantly reduced the levels of mRNA for HAS 1 when compared to MEM, this factor has increased the levels of versican and perlecan. In addition, the presence of both FSH and GDF-9 increased mRNA levels for HAS 2, but reduced level those for PCNA. In addition, FSH also acts by reducing mRNA levels for PCNA. In conclusion, FSH and/or GDF-9 promotes the follicular growth and antrum formation, and GDF-9 stimulates the expression of versican and perlecan and interact positively with FSH to the increased expression of HAS 2 / O objetivo deste estudo foi determinar o papel do GDF-9 sozinho ou em combinação com FSH sobre a viabilidade, crescimento e expressão do RNAm para PCNA, HAS 1, HAS 2, versican e perlecan em Folículos secundários bovinos cultivados in vitro. Para estudos in vitro, folículos secundários bovinos foram isolados e cultivados por doze dias, na presença de MEM sozinho ou suplementado com GDF-9 (200 g/mL), FSH (D0-D6: 100 ng/mL e de D7-D12: 500 ng/mL) ou ambos. Diâmetro folicular, viabilidade e formação de antro foram avaliados durante o cultivo. Para avaliar os níveis de RNAm para PCNA, HAS 1, HAS 2, Perlecan e versican em folículos após 12 dias de cultivo, o RNA total foi extraído e o cDNA foi sintetizado. Os níveis de RNAm foram quantificados por PCR em tempo real. O teste Kruskal-Wallis foi usado para comparar o diâmetro folicular. O teste Qui-quadrado foi utilizado para comparar a porcentagem de viabilidade e formação de antro de folículos após o cultivo in vitro (p<0,05), enquanto ANOVA seguido pelo teste de Tukey foram utilizados para avaliar os dados de expressão do RNAm nos folículos cultivados (p<0,05). Os resultados mostram que após 6 dias de cultivo, FSH sozinho ou associado com GDF-9 aumentaram o diâmetro folicular em relação ao meio controle. Além disso, após 12 dias de cultivo, FSH promoveu um aumento no diâmetro folicular, enquanto a associação de FSH com GDF-9 reduziu significativamente o diâmetro folicular quando comparado com folículos cultivados em MEM acrescido de FSH. Além disso, FSH e GDF-9 aumentaram a formação de antro após 12 dias de cultivo (P<0,05). Apesar de GDF-9 ter reduzido significativamente os níveis de RNA para HAS 1 quando comparado ao MEM, esse fator aumentou os níveis de versican e perlecan. Além disso, a presença de ambos FSH e GDF-9 aumentaram os níveis de RNAm para HAS 2, porém, reduziu os níveis de RNAm para PCNA. Além disso, FSH também atua reduzindo os níveis de RNAm para o PCNA. Em conclusão, FSH e/ou GDF-9 promovem o crescimento folicular e formação de antro, e GDF-9 estimula a expressão de versican e perlecan e interage positivamente com FSH para o aumento da expressão de HAS 2.

Memoria para optar al Título Profesional de Médico Veterinario / El Factor de Crecimiento Diferencial 9 (GDF9) cumple un rol esencial en el desarrollo ovocitario de los mamíferos, sin embargo, en ovocitos caninos se desconoce su presencia y participación durante la maduración. En este estudio, se evaluó la presencia de GDF9 en ovocitos de perra madurados in vitro (MIV) y su relación con la expansión del cúmulo, para lo cual complejos cúmulo ovocito (COC’s) se cultivaron por 0, 48, 72 y 96 h. Posteriormente, algunos COC’s fueron desprendidos del cúmulo. De este modo, ovocitos sin células del cúmulo y COC’s se procesaron para su evaluación a través de Inmunofluorescencia Indirecta y Western blot con el anticuerpo anti GDF9 humano. Con ambas técnicas, la proteína se detectó principalmente en el ovocito y en menor proporción en las células del cúmulo. Además, en ambos tipos celulares, la detección de GDF9 disminuyó a medida que progresó el tiempo de cultivo. En ovocitos denudados y COC’s, se detectó una banda de ~56 kDa correspondiente a la pro-proteína en todos los tiempos de maduración. Sin embargo, sólo en COC’s no madurados y MIV por 48 h se detectaron dos bandas de proteína madura de ~18 y 19 kDa. Finalmente, se observó una relación inversa entre la expansión del cúmulo durante la MIV y la detección de GDF9 por Western blot. Por consiguiente, GDF9 está presente en ovocitos de perra y tendría participación en los procesos iniciales del crecimiento y desarrollo ovocitario / Financiamiento: Proyecto Fondecyt 1110265

Stuttgart, Univ., Diss., 1996.

GDF-15 wird seit wenigen Jahren als prognostischer und prädiktiver Marker in der Tumortherapie diskutiert. Diese Pilotstudie sollte erstmals GDF-15 bei Patienten mit HER2/neu positivem Mammakarzinom im frühen Stadium im klinischen Verlauf untersuchen. Dazu wurden 22 Patienten rekrutiert und die GDF-15-Spiegel mittels ELISA vor und während einer Antikörpertherapie bestimmt. Um GDF-15 als prädiktiven Marker zu testen, wurde nach neoadjuvanter Therapie und anschließender Operation der Regressionsgrad nach Sinn bewertet. In der untersuchten Kohorte wurde ein medianer GDF 15-Spiegel von 0,33 ng/ml ermittelt. Im Therapieverlauf kam es zu keiner signifikanten Veränderung des Spiegels. Höhere GDF-15-Spiegel konnten allerdings bei größeren Tumoren und bei einem höheren BMI analysiert werden. Ebenfalls konnten wir zeigen, dass der GDF-15-Spiegel signifikant mit dem Alter steigt. Nicht signifikant, aber von Bedeutung ist der Zusammenhang zwischen GDF-15 und dem Regressionsgrad nach Sinn. Die untersuchten Patienten wiesen tendenziell höhere GDF-15-Werte bei niedrigem Regressionsgrad auf. Ein schlechteres Ansprechen auf eine Antikörpertherapie bei höheren GDF 15-Spiegeln ist somit anzunehmen. / GDF-15 as a prognostic and predictive marker in tumortherapy is actively discussed. In this pilot study we analysed the GDF-15 levels before an while antibody-therapy in patients with early her2-positiv breast cancer and correlated those with clinical variables. Overall we found relatively low GDF-15 levels. The correlation of GDF-15 with the sinn regression was not significant but showed a tendency. This indicates a worse response rate to a antibody-therapy for patients with higher GDF-15 serum levels.

No description available.

Kurzzusammenfassung: Dank der Einführung von Immuncheckpointinhibitoren hat sich die Therapie fortgeschrittener onkologischer Erkrankungen in den letzten Jahren dramatisch verändert. Trotz außergewöhnlicher Erfolge profitieren viele Patienten jedoch weder akut noch langfristig von einer Behandlung, tragen aber alle ihre Risiken. Ein besseres Verständnis davon, bei welchen Patienten diese Therapieform wirkt, sowie prädiktive Marker werden daher dringend benötigt. Growth Differentiation Factor 15 (GDF-15) ist Teil der Transforming Growth Factor-β Superfamilie, weist in pathologischen Situationen wie Entzündungen und insbesondere bei Krebs sehr hohe Spiegel auf und besitzt in verschiedenen, auch onkologischen Erkrankungen einen starken prognostischen Wert. Möglicherweise könnte GDF-15 durch seine immunmodulierenden Eigenschaften dazu beitragen, dass Krebszellen im Körper nicht angegriffen werden, und die Wirksamkeit einer Immuncheckpointblockade (ICB) dadurch vermindern. Ziel der vorliegenden Pilotstudie war es zu untersuchen, ob ein Zusammenhang zwischen dem GDF-15-Spiegel und dem Erfolg einer ICB besteht. Hierfür wurden 37 Patienten verschiedener onkologischer Entitäten vor Beginn einer ICB auf ihre GDF-15-Spiegel untersucht, sowie nach zwölf bzw. bei Progressive Disease zum Teil auch nach vier Wochen Therapie. Die Bewertung des Therapieergebnisses erfolgte anhand der RECIST sowie der klinischen Präsentation. Ein Therapieerfolg wurde ab Erreichen einer Stable Disease klassifiziert. Die Rekrutierungszeit betrug 23 Monate ab Januar 2017. Die Untersuchungen zeigten vor Therapiebeginn einer ICB einen geringen Unterschied der GDF-15-Spiegel zwischen Patienten mit Therapieerfolg und Therapieversagen (Median des Therapieerfolgs: 0,63 ng/ml versus Median des Therapieversagens: 0,92 ng/ml). Dieser Unterschied war statistisch nicht signifikant. Dagegen zeigte sich ein signifikanter Zusammenhang zwischen einem Anstieg des GDF-15-Spiegels unter Therapie und dem Therapieversagen einer ICB. Bei Therapieerfolg sank oder stagnierte der GDF-15-Spiegel im Median um - 0,01 ng/ml. Dagegen stieg er bei Therapieversagen im Median um + 0,7 ng/ml an (p < 0,01 r = 0,43). Auch die Höhe des GDF-15-Spiegels unter Therapie zeigte einen signifikanten Zusammenhang mit dem Therapieergebnis. Der GDF-15-Spiegel unter Therapie lag im Median bei Patienten mit Therapieerfolg bei 0,72 ng/ml, dagegen bei Patienten mit Therapieversagen bei 1,85 ng/ml (p < 0,01 r = 0,47). Ob der GDF-15-Spiegel vor Therapiebeginn die Wirksamkeit einer ICB vorhersagen kann, bleibt unklar, da in dieser Studie nur eine Tendenz aufgezeigt werden konnte, die in Folgestudien mit größeren Kohorten in den verschiedenen Entitäten untersucht werden sollte. Unsere Daten zeigen jedoch einen Zusammenhang zwischen einem steigenden bzw. erhöhten GDF-15-Spiegel unter Therapie mit dem Therapieergebnis einer ICB. Dieser Zusammenhang fügt sich gut in das Bild gegenwärtiger Diskussionen über immunmodulierende Eigenschaften von GDF-15 und seiner Rolle bei der Tumorprogression. Zugleich bestärkt das Studienergebnis die Annahme, in GDF-15 auch ein vielversprechendes Angriffsziel therapeutischer Ansätze gefunden zu haben. / Abstract: Thanks to the introduction of immune checkpoint inhibitors, therapy of progressed oncological diseases has changed dramatically in recent years. However, many patients benefit neither acutely nor in the long term from the treatment but bear all its risks. A better understanding of which patients profit from this therapy as well as predictive markers are therefore urgently needed. Growth Differentiation Factor 15 (GDF-15) is part of the Transforming Growth Factor-β superfamily. It shows raised levels in pathological situations such as inflammation and reaches especially in cancer remarkably high levels. It has a strong prognostic value in various, also oncological diseases. Possibly, GDF-15 helps cancer cells not to be attacked by the immune system and could thereby reduce the effectiveness of an immune checkpoint blockade (ICB). The aim of the presented pilot study was investigating whether there is a connection between the GDF-15 level and the success of an ICB. For this purpose, the GDF-15 level of 37 patients of different oncological entities were examined before the start of an ICB, as well as after twelve weeks of therapy, or in the case of progressive disease, after four weeks of therapy. The evaluation of the therapy results was based on RECIST and the clinical presentation. The time of recruitment was 23 months since January 2017. For the GDF-15 level before start of an ICB therapy, the investigations showed a small difference between patients with therapy success and therapy failure (median when success of the therapy: 0.63 ng/ml versus median when treatment failure: 0.92 ng/ml). But this difference was not statistically significant. In contrast, during therapy there was a significant connection between an increase in the GDF-15 level and therapy failure of the ICB. In case of successful therapy, the GDF-15 level fell or stagnated with a median of -0.01 ng/ml. In contrast, the GDF-15 level rose with a median of +0.7 ng/ml in case of therapy failure (p<0.01 r=0.43). Also, the absolute height of the GDF-15 level during therapy showed a significant connection with the therapy result. The median of the GDF-15 level during therapy of patients with therapy success was 0.72 ng/ml, but of patients with treatment failure was 1.85 ng/ml (p<0.01 r = 0.47). Whether the GDF-15 level can predict the effectiveness of an ICB before the start of therapy remains unclear, since this study could only show a trend that follow-up studies with larger cohorts for the different entities should further examine. However, our data show a correlation between increasing and increased GDF-15 levels under therapy with the therapy result of an ICB. This correlation fits well with current discussions about immunomodulating properties of GDF-15 and its role in tumor progression. Simultaneously, the study result confirms the assumption of GDF-15 being a promising target of new therapeutic approaches.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O objetivo deste estudo foi investigar os nÃveis de RNA mensageiro (RNAm) para ativina-A em folÃculos prÃ-antrais e antrais caprinos e os efeitos do hormÃnio folÃculo estimulante (FSH), ativina-A e fator de crescimento e diferenciaÃÃo - 9 (GDF-9) sobre o crescimento e a expressÃo de RNAm para ativina-A, GDF-9, proteÃna morfogenÃtica Ãssea (BMP) -2, -4, -6, -7, -15 e receptor de FSH (R-FSH) em folÃculos prÃ-antrais caprinos cultivados in vitro. Inicialmente, folÃculos primordiais, primÃrios e secundÃrios, bem como complexos cumulus-oÃcito (COCs) e cÃlulas da granulosa mural/teca de pequenos e grandes folÃculos antrais foram isoladas mecanicamente a partir de ovÃrios de cabra e a expressÃo de RNAm para ativina-A foi avaliada por PCR em tempo real. Para os estudos in vitro, folÃculos secundÃrios caprinos foram isolados e cultivados por 6 dias na presenÃa de FSH sozinho (50 ng/mL) ou em combinaÃÃo com ativina-A (100 ng/mL) ou GDF-9 (200 ng/mL). Isoladamente ou em combinaÃÃo com FSH, a influÃncia de ativina-A na expressÃo de ativina-A e R-FSH, e o efeito do GDF-9 sobre os nÃveis de RNAm para GDF-9, R-FSH e BMP -2, -4 , -6, -7 e -15 em folÃculos secundÃrios apÃs 6 dias de cultivo foram testados. Para isso, apÃs a extraÃÃo do RNA total e sÃntese do cDNA, os nÃveis de RNAm para ativina-A, GDF-9, R-FSH e BMP -2, -4, -6, -7 e -15 foram quantificados por PCR em tempo real. Os resultados mostraram que folÃculos secundÃrios apresentavam nÃveis menores de RNAm para ativina-A comparado aos folÃculos primÃrios (p<0,05). NÃo houve diferenÃa nos nÃveis de RNAm para ativina-A entre folÃculos primordial e primÃrio ou secundÃrio (p>0,05). Aliado a isso, nÃo houve diferenÃa entre COCs de pequenos e grandes folÃculos antrais (p>0,05). AlÃm disso, as cÃlulas da granulosa e da teca de grandes folÃculos antrais apresentaram maiores nÃveis de RNAm para ativina-A do que de pequenos folÃculos antrais (p<0,05). Quando comparamos a expressÃo do RNAm para ativina-A entre COCs de pequenos e grandes folÃculos antrais e suas cÃlulas da granulosa e da teca, nenhuma diferenÃa nos nÃveis de expressÃo foi observada (p>0,05). ApÃs o cultivo in vitro de folÃculos secundÃrios, a presenÃa de FSH sozinho ou associado com ativina-A ou GDF-9 aumentou a sobrevivÃncia, crescimento folicular e formaÃÃo de antro (p<0,05). O FSH tambÃm aumentou o RNAm para ativina-A, enquanto os folÃculos cultivados com ativina-A apresentaram nÃveis aumentados de RNAm para R-FSH (p<0,05). AlÃm disso, o GDF-9 diminuiu a expressÃo de RNAm para BMP -2 e -15 (p<0,05), mas nÃo teve efeito sobre a expressÃo de BMP -4, -6 e -7 (p>0,05). Em conclusÃo, durante a transiÃÃo de folÃculo primÃrio para secundÃrio hà uma diminuiÃÃo do RNAm para ativina-A, enquanto ocorre um aumento da expressÃo deste fator durante o crescimento de folÃculos antrais. FSH, ativina-A e GDF-9 estimulam o crescimento de folÃculos secundÃrios caprinos apÃs 6 dias de cultivo. ApÃs cultivo folicular, FSH controla a expressÃo de ativina-A e a expressÃo do R-FSH à regulada por ativina-A. Ainda, GDF-9 reduz a expressÃo do RNAm para BMP -2 e -15. / The aim of this study was to investigate the levels of messenger RNA (mRNA) for activin-A on goat preantral and antral follicles and the effects of follicle stimulating hormone (FSH), activin-A and growth and differentiation factor - 9 (GDF-9) on growth and mRNA expression for activin-A, GDF-9, bone morphogenetic protein (BMP) -2, -4, -6, -7, -15 and FSH receptor (FSH-R) in goat preantral follicles cultured in vitro. Initially, primordial, primary and secondary follicles, as well as cumulus-oocyte complexes (COCs) and mural granulosa/theca cells of small and large antral follicles were isolated mechanically from goat ovaries and the expression of mRNA for activin-A was evaluated by real-time PCR. For in vitro studies, goat secondary follicles were isolated and cultured for 6 days in the presence of FSH alone (50 ng/mL) or in combination with activin-A (100 ng/mL) or GDF-9 (200 ng/mL). Alone or in combination with FSH, the influence of activin-A on expression of activin-A and FSH-R, and the effect of GDF-9 on the levels of mRNA for GDF-9, FSH-R and BMP -2, -4, -6, -7 and -15 in secondary follicles after 6 days of culture were tested. For this, after extraction of total RNA and cDNA synthesis, the levels of mRNA for activin-A, GDF-9, FSH-R and BMP -2, -4, -6, -7 and -15 were quantified by real time PCR. The results showed that secondary follicles had lower levels of mRNA for activin-A, than compared to primary follicles (p<0.05). There was no difference in levels of mRNA for activin-A between primordial and primary or secondary (p>0.05). Allied to this, there was no difference between COCs of small and large antral follicles (p>0.05). Moreover, granulosa and theca cells of large antral follicles showed higher levels of mRNA for activin-A than in small antral follicles (p<0.05). When comparing mRNA expression for activin-A between COCs from small and large antral follicles and their granulosa and theca cells, no difference in expression levels was observed (p>0.05). After in vitro culture of secondary follicles, the presence of FSH either alone or associated with activin-A or GDF-9 increased survival, follicular growth and antrum formation (p<0.05). The FSH increased mRNA for activin-A, while the follicles cultured with activin-A showed increased levels of mRNA for FSH-R (p<0.05). In addition, GDF-9 decreased mRNA expression for BMP -2 and -15 (p<0.05), but had no effect on expression of BMP -4, -6, and -7 (p>0.05). In conclusion, during the transition from primary to secondary follicles there is a reduction of mRNA for activin-A, whereas there is an increased expression of this factor during the growth of antral follicles. FSH, activin-A and GDF-9 stimulate growth of goat secondary follicles after 6-day culture. After follicle culture FSH controls the expression of activin-A, and the expression of FSH-R is regulated by activin-A. Furthermore, GDF-9 reduces the mRNA expression for BMP-2 and -15.

O objetivo deste estudo foi determinar o papel do GDF-9 sozinho ou em combinaÃÃo com FSH sobre a viabilidade, crescimento e expressÃo do RNAm para PCNA, HAS 1, HAS 2, versican e perlecan em folÃculos secundÃrios bovinos cultivados in vitro. Para estudos in vitro, folÃculos secundÃrios bovinos foram isolados e cultivados por doze dias, na presenÃa de MEM sozinho ou suplementado com GDF-9 (200 ng/mL), FSH (D0-D6: 100 ng/mL e de D7-D12: 500 ng/mL) ou ambos. DiÃmetro folicular, viabilidade e formaÃÃo de antro foram avaliados durante o cultivo. Para avaliar os nÃveis de RNAm para PCNA, HAS 1, HAS 2, perlecan e versican em folÃculos apÃs 12 dias de cultivo, o RNA total foi extraÃdo e o cDNA foi sintetizado. Os nÃveis de RNAm foram quantificados por PCR em tempo real. O teste Kruskal-Wallis foi usado para comparar o diÃmetro folicular. O teste Qui-quadrado foi utilizado para comparar a porcentagem de viabilidade e formaÃÃo de antro de folÃculos apÃs o cultivo in vitro (p<0,05), enquanto ANOVA seguido pelo teste de Tukey foram utilizados para avaliar os dados de expressÃo do RNAm nos folÃculos cultivados (p<0,05). Os resultados mostram que apÃs 6 dias de cultivo, FSH sozinho ou associado com GDF-9 aumentaram o diÃmetro folicular em relaÃÃo ao meio controle. AlÃm disso, apÃs 12 dias de cultivo, FSH promoveu um aumento no diÃmetro folicular, enquanto a associaÃÃo de FSH com GDF-9 reduziu significativamente o diÃmetro folicular quando comparado com folÃculos cultivados em MEM acrescido de FSH. AlÃm disso, FSH e GDF-9 aumentaram a formaÃÃo de antro apÃs 12 dias de cultivo (P<0,05). Apesar de GDF-9 ter reduzido significativamente os nÃveis de RNA para HAS 1 quando comparado ao MEM, esse fator aumentou os nÃveis de versican e perlecan. AlÃm disso, a presenÃa de ambos FSH e GDF-9 aumentaram os nÃveis de RNAm para HAS 2, porÃm, reduziu os nÃveis de RNAm para PCNA. AlÃm disso, FSH tambÃm atua reduzindo os nÃveis de RNAm para o PCNA. Em conclusÃo, FSH e/ou GDF-9 promovem o crescimento folicular e formaÃÃo de antro, e GDF-9 estimula a expressÃo de versican e perlecan e interage positivamente com FSH para o aumento da expressÃo de HAS 2. / The aim of this study was to determine the role of GDF-9 alone or in combination with FSH on growth, viability and on the mRNA expression of PCNA, HAS 1, HAS 2, versican and perlecan in bovine secondary follicles cultured in vitro. For in vitro studies, bovine secondary follicles were isolated and cultured for twelve days in the presence of MEM alone or supplemented with GDF-9 (200 ng/mL), FSH (D0-D6: 100 ng/mL and of D7-D12: 500 ng/mL) or both. Follicular diameter, viability and antrum formation were evaluated during culture. To evaluate the mRNA levels for PCNA, perlecan, versican, HAS 1 and 2 in follicles after 12 days of culture, total RNA was extracted and cDNA was synthesized. The levels of mRNA were quantified by real time PCR. Kruskal-Wallis test were used to compare the follicular diameter. The chi-square test was used to compare the percentage of viability and antrum formation of follicles after in vitro culture (p<0.05), whereas ANOVA followed by Tukey's test were used to evaluate the mRNA expression data in cultured follicles (p<0.05). The results show that after 6 days of culture, FSH alone or associated with GDF-9 increased follicular diameter in relation to control medium. Moreover, after 12 days of culture, FSH promoted an increase in follicular diameter, while the association of FSH with GDF-9 significantly reduced follicular diameter when compared with follicles cultured in MEM plus FSH. Furthermore, FSH and GDF-9 increased the antrum formation after 12 days of culture (P<0.05). Despite GDF-9 had significantly reduced the levels of mRNA for HAS 1 when compared to MEM, this factor has increased the levels of versican and perlecan. In addition, the presence of both FSH and GDF-9 increased mRNA levels for HAS 2, but reduced level those for PCNA. In addition, FSH also acts by reducing mRNA levels for PCNA. In conclusion, FSH and/or GDF-9 promotes the follicular growth and antrum formation, and GDF-9 stimulates the expression of versican and perlecan and interact positively with FSH to the increased expression of HAS 2

Une des difficultés majeures dans le traitement des cancers est l’acquisition de résistance par les cellules tumorales vis-à-vis de la mort induite par les différentes chimiothérapies. Au sein du laboratoire, nous nous intéressons aux propriétés anti-tumorales d’un donneur de monoxyde d’azote (NO), le Glycéryl TriNitrate (GTN), fréquemment utilisé dans le traitement de l’angine de poitrine. Au cours de ce travail, nous avons étudié les mécanismes moléculaires par lesquels le GTN sensibilise les cellules tumorales de plusieurs types de cancer (colique, mammaire, prostatique) à la mort impliquant des voies de signalisation régulées par des cytokines telles que le TNFα, l’IL-6 ou encore le GDF-15.Une meilleure compréhension des mécanismes sous-jacents à l’action anti-tumorale du GTN permettrait de potentialiser son utilisation comme nouvelle thérapie anti-cancéreuse.Modèle colique : le GTN, en présence de la cytokine pro-inflammatoire TNFα, sensibilise les cellules cancéreuses coliques et mammaires à l’apoptose. Du point de vue mécanistique, le GTN induit la S-nitrosylation de cIAP1, inhibant ainsi son activité ubiquitine E3 ligase. Ce qui abroge la voie de signalisation classique NF-кB de survie cellulaire activée par la voie TNFα/TNFR1 en faveur d’une voie de signalisation pro-apoptotique.Modèle mammaire : le GTN intervient au niveau de la migration cellulaire en altérant la voie de signalisation Jak2/STAT3 activée par la cytokine pro-inflammatoire IL-6, dans un modèle de cancer du sein triple négatif. En présence de dérivés du platine (carboplatine) générant de l’IL-6, le GTN freine la migration des cellules en induisant la S-nitrosylation, et probablement l’inactivation, de la kinase Jak-2, indispensable pour l’activation de la voie.Modèle prostatique : le GTN sensibilise à la mort les cellules cancéreuses prostatiques résistantes au docétaxel en modulant le taux de deux marqueurs de résistance à cette chimiothérapie : la clusterine (CLU) et le growth differentiation factor 15 (GDF-15). Au niveau moléculaire, le GTN diminue le taux de l'isoforme cytoprotectrice soluble de la CLU (sCLU) et augmente le taux de l'isoforme cytotoxique nucléaire (nCLU) dans les cellules prostatiques résistantes au docétaxel. Plus particulièrement, en présence de GTN, nous avons établi un lien entre le GDF-15 et la modulation du taux des isoformes de la CLU. / One of the main difficulties in the treatment of cancers is the acquisition of resistance by the tumor cells vis-à-vis the death induced by the different chemotherapies. In the laboratory, we are interested in the anti-tumor properties of a nitric oxide (NO) donor, Glyceryl TriNitrate (GTN), frequently used in the treatment of angina pectoris. In this work, we investigated the molecular mechanisms by which GTN sensitizes tumor cells of several types of cancer (colonic, mammary, prostate) to death involving signaling pathways regulated by cytokines such as TNFα, IL-6 or GDF-15.A better understanding of the mechanisms underlying the GTN's anti-tumor action would make it possible to use it as a new anti-cancer therapy.Colon model: GTN, in the presence of the pro-inflammatory cytokine TNFα, sensitizes colon and mammary cancer cells to apoptosis. From a mechanistic point of view, GTN induces S-nitrosylation of cIAP1, thus inhibiting its ubiquitin E3 ligase activity. This abrogates the classical NF-κB signaling pathway of TNFα / TNFR1 activated cell survival in favor of a pro-apoptotic signaling pathway.Mammary model: GTN intervenes at the level of cell migration by altering the Jak2 / STAT3 signaling pathway activated by the pro-inflammatory cytokine IL-6, in a model of triple negative breast cancer. In the presence of platinum (carboplatin) derivatives generating IL-6, GTN inhibits cell migration by inducing S-nitrosylation, and probably inactivation, of Jak-2 kinase, essential for the activation of the way.Prostate model: GTN sensitizes prostatic prostate cancer cells to death by modulating the level of two markers of resistance to this chemotherapy: clusterin (CLU) and growth differentiation factor 15 (GDF-15). At the molecular level, GTN decreases the level of the soluble cytoprotective isoform of CLU (sCLU) and increases the level of nuclear cytotoxic isoform (nCLU) in prostatic cells resistant to docetaxel. More particularly, in the presence of GTN, we have established a link between GDF-15 and the modulation of the isoform rate of the CLU.