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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

Efeito da administração de octreotide, cabergolina e a associação de ambos nos níveis de ACTH e cortisol em pacientes com doença de Cushing: correlação da resposta clínica com a expressão tumoral dos receptores de dopamina  (DRD2) e de somatostatina (SSTR2 e SSTR5) / Effect of the administration of octreotide, cabergoline and the association of both on ACTH and cortisol levels in patients with Cushings disease: correlation of clinical response with tumoral expression of the dopamine (DRD2) and somatostatin (SSTR2 and SSTR5) receptors

Romanholi, Daniella de Jesus Patrick Carminatti 31 August 2010 (has links)
Introdução: A doença de Cushing apresenta elevada morbimortalidade. Seu tratamento de escolha é a cirurgia transesfenoidal que possui resultados satisfatórios em cerca de 70% dos casos. Na doença persistente ou recorrente, reabordagem cirúrgica, radioterapia e adrenalectomia bilateral podem ser realizadas, porém, essas opções apresentam como desvantagens o desenvolvimento de hipopituitarismo e a dependência de terapia de reposição. Até o momento, nenhuma droga tem se mostrado eficaz no tratamento do corticotrofinoma. Os esquemas terapêuticos mais eficazes são os inibidores da esteroidogênese que não atuam no tumor hipofisário. Objetivos: avaliar o efeito do octreotide e da cabergolina administrados isoladamente e em associação nas concentrações urinárias de cortisol e plasmáticas de ACTH em pacientes com corticotrofinomas; correlacionar esse efeito com a expressão tumoral dos receptores SSTR2, SSTR5 e DRD2; correlacionar a expressão tumoral desses receptores através de RT-PCR quantitativa e imunohistoquímica; avaliar se o uso prévio dessas drogas altera a expressão desses receptores. Casuística e Métodos: grupo controle composto por 11 pacientes (10 mulheres e 1 homem) entre 21 e 43 anos sem tratamento prévio à neurocirurgia e um grupo tratado formado por 11 pacientes (2 homens e 9 mulheres) entre 22 e 53 anos que receberam o seguinte tratamento antes da cirurgia: coleta de três amostras de cortisol urinário e ACTH plasmático, seguida da introdução de octreotide 100 g, subcutâneo, 8/8h durante 30 dias e nova coleta de três amostras de cortisol urinário e ACTH plasmático. Em seguida, iniciou-se a cabergolina 0,5 mg via oral 3 vezes na semana durante 30 dias com nova coleta de três amostras de cortisol urinário e ACTH plasmático. A seguir, o octreotide era associado por mais 30 dias com nova coleta de três amostras de cortisol urinário e ACTH plasmático. Resultados: Os valores de cortisol urinário apresentaram queda significante após o uso de cabergolina isolada (P = 0,016) e em associação ao octreotide (P = 0,012). A eficácia do tratamento combinado não foi maior que a da cabergolina isolada. Os valores de ACTH plasmático não revelaram diferença significante durante o tratamento e não se correlacionaram com os valores de cortisol. A média de expressão do mRNA do gene DRD2 foi maior no grupo tratado (1,170 ± 0,417) quando comparada ao grupo controle (0,776 ± 0,252) (P = 0,036). Houve dissociação entre os conteúdos de mRNA e da proteína desse receptor. Não foi possível analisar a expressão do mRNA do gene SSTR5, pois o tratamento das amostras com DNAse causou degradação do RNA. A imunorreatividade para SSTR5 esteve presente em todos os pacientes e não foi alterada pelo tratamento prévio. Não houve diferença estatística na expressão do gene SSTR2 entre os grupos controle (1,253 ± 0,511) e tratado (1,267 ± 0,386) bem como diferença significante da imunoexpressão do SSTR2 entre os grupos. Houve correlação entre os conteúdos de mRNA e da proteína desse receptor (P = 0,021). Não houve correlação entre a expressão dos receptores analisados e a resposta ao octreotide e à cabergolina isoladamente ou em associação. Conclusões: a cabergolina isolada representa opção terapêutica na doença de Cushing persistente ou recorrente. A associação de octreotide na dose estudada por 30 dias não foi mais eficiente em reduzir o cortisol urinário. A resposta a essas drogas não está relacionada à expressão dos receptores SSTR2, SSTR5 e DRD2 / Introduction: The Cushings disease presents high morbimortality. Its treatment of choice is transsphenoidal surgery which has satisfactory results in about 70% of cases. In persistent or recurrent disease, a second transsphenoidal surgery, radiotherapy and bilateral adrenalectomy can be carried through, however, these options present disadvantages as development of hypopituitarism and lifelong dependence on hormone replacement therapy. Presently, no drug has shown efficacy in corticotrophinomas treatment. The most efficient agents are the inhibitors of steroidogenesis which have no effect at pituitary tumor. Objectives: To evaluate isolated octreotide and cabergoline effects and their association on plasma ACTH and urinary cortisol in Cushings disease patients, to correlate this effect with tumoral expression of SSTR2, SSTR5 and DRD2 receptors; to correlate tumoral expression of these receptors by quantitative RT-PCR and immunohistochemistry; to evaluate whether these drugs modifies these receptors expression. Patients and methods: control group with 11 patients (10 women and 1 man) between 21 and 43 years who underwent pituitary surgery with no prior treatment and a treated group with 11 patients (2 men and 9 women) between 22 and 53 years that received the following treatment before surgery: : after three baseline urinary cortisol samples and one plasma ACTH sample, patients received octreotide 100 g, subcutaneous 8/8h for 30 days collecting three urinary cortisol samples and one plasma ACTH. After that, cabergoline was introduced 0,5 mg 3x/week for 30 days collecting three urinary cortisol samples and one plasma ACTH sample. Then, octreotide was associated to cabergoline for another 30 days followed by three urinary cortisol and one plasma ACTH sample. Results: Urinary cortisol concentrations significantly decreased after isolated and combined cabergoline use (P = 0,016 and P = 0,012, respectively). Combined treatment efficacy was not greater than isolated cabergoline administration. Plasma ACTH did not change statistically during treatment and did not correlate with urinary cortisol. The average of DRD2 gene expression was higher in control group (0,776 ± 0,252) in relation to treated group (1,170 ± 0,417) (P = 0,036). It had dissociation between mRNA and protein contents of this receptor. SSTR5 gene mRNA expression was not analyzed due to RNA degradation after DNAse tissue treatment. SSTR5 immunoreactivity was present in all patients and it was not modified by previous treatment. No statistic difference was observed between SSTR2 gene expression in control group (1,253 ± 0.511) and in treated group (1,267 ± 0,386). There was no significant difference in SSTR2 immunoexpression between groups. It had correlation between the mRNA and protein contents of this receptor (P = 0.021). No significant relationship was found between hormonal response to isolated and combined therapy and receptors mRNA expression levels. Conclusions: cabergoline represents therapeutical option in persistent or recurrent Cushings disease. Octreotide-cabergoline association in the studied dosage and for the period of 30 days was not more efficient in eliciting urinary cortisol reduction. The responsiveness to these drugs did not correlate to SSTR2 and DRD2 mRNA expression
12

The Regulation of Growth and Survival in Human Multiple Myeloma Cells by IGF-I Receptor Signaling

Strömberg, Thomas January 2003 (has links)
<p>Multiple myeloma (MM) is an incurable B-cell malignancy mainly localized to the bone marrow. Our aim was to examine the growth- and survival-promoting role of the IGF-IR and its downstream signaling components in MM cells to identify potential targets for therapy. </p><p>Octreotide, a somatostatin analog that has been demonstrated to interfere with the actions of IGF-I, induced growth inhibition in both IL-6-dependent and IL-6-independent MM cell lines expressing the somatostatin receptors sst2, sst3 and sst5. Additionally, a slight pro-apoptotic effect could be observed in a few cell lines. In primary MM cells octreotide induced apoptosis, an effect that was abrogated by exogenously added IGF-I, but not by IL-6.</p><p>Inhibition of IGF-I signaling in Karpas 707 cells, using either the anti-IGF-IR antibody αIR3 or the PI 3-K inhibitors LY294002 and wortmannin, increased sensitivity to apoptosis induced by dexamethasone. Exogenously added IGF-I prevented dexamethasone-induced apoptosis, an effect that could partly be mimicked by the pharmacological GSK-3β inhibitors LiCl and SB415286. Thus, we suggest the GSK-3β as an important mediator of the anti-apoptotic effects of IGF-IR signaling in MM.</p><p>Using rapamycin we selectively inhibited mTOR, a phosphoprotein downstream of the IGF-IR. In MM cell lines rapamycin induced G0/G1-arrest, an effect being associated with an increase of the cyclin-dependent kinase inhibitor p27 and a decrease of the cyclins D2, D3 and E. Interestingly, in primary MM cells rapamycin induced apoptosis. Moreover, rapamycin potentiated dexamethasone-induced apoptosis, an effect that was associated with a downregulation of the anti-apoptotic protein survivin. Strikingly, the combinatorial treatment with rapamycin and dexamethasone suppressed the anti-apoptotic effects of exogenously added IGF-I and IL-6, thus suggesting this drug-combination to be active also in vivo. </p><p>Two newly developed, selective IGF-I RTK inhibitors proved to be very effective in MM cell lines and in primary MM cells providing 50-90% growth inhibition within 48 h of incubation. The inhibitors induced massive apoptosis together with a prominent cell cycle arrest in the G2/M-phase. Importantly, the IGF-I RTK inhibitors downregulated the tyrosine phosphorylation of the IGF-IR β-chain but not of the insulin receptor β-chain. </p><p>In conclusion, the IGF-IR potently promotes growth and survival of MM cells. Therefore, interfering with the IGF-IR signaling pathway might be a suitable strategy to improve MM treatment.</p>
13

The Regulation of Growth and Survival in Human Multiple Myeloma Cells by IGF-I Receptor Signaling

Strömberg, Thomas January 2003 (has links)
Multiple myeloma (MM) is an incurable B-cell malignancy mainly localized to the bone marrow. Our aim was to examine the growth- and survival-promoting role of the IGF-IR and its downstream signaling components in MM cells to identify potential targets for therapy. Octreotide, a somatostatin analog that has been demonstrated to interfere with the actions of IGF-I, induced growth inhibition in both IL-6-dependent and IL-6-independent MM cell lines expressing the somatostatin receptors sst2, sst3 and sst5. Additionally, a slight pro-apoptotic effect could be observed in a few cell lines. In primary MM cells octreotide induced apoptosis, an effect that was abrogated by exogenously added IGF-I, but not by IL-6. Inhibition of IGF-I signaling in Karpas 707 cells, using either the anti-IGF-IR antibody αIR3 or the PI 3-K inhibitors LY294002 and wortmannin, increased sensitivity to apoptosis induced by dexamethasone. Exogenously added IGF-I prevented dexamethasone-induced apoptosis, an effect that could partly be mimicked by the pharmacological GSK-3β inhibitors LiCl and SB415286. Thus, we suggest the GSK-3β as an important mediator of the anti-apoptotic effects of IGF-IR signaling in MM. Using rapamycin we selectively inhibited mTOR, a phosphoprotein downstream of the IGF-IR. In MM cell lines rapamycin induced G0/G1-arrest, an effect being associated with an increase of the cyclin-dependent kinase inhibitor p27 and a decrease of the cyclins D2, D3 and E. Interestingly, in primary MM cells rapamycin induced apoptosis. Moreover, rapamycin potentiated dexamethasone-induced apoptosis, an effect that was associated with a downregulation of the anti-apoptotic protein survivin. Strikingly, the combinatorial treatment with rapamycin and dexamethasone suppressed the anti-apoptotic effects of exogenously added IGF-I and IL-6, thus suggesting this drug-combination to be active also in vivo. Two newly developed, selective IGF-I RTK inhibitors proved to be very effective in MM cell lines and in primary MM cells providing 50-90% growth inhibition within 48 h of incubation. The inhibitors induced massive apoptosis together with a prominent cell cycle arrest in the G2/M-phase. Importantly, the IGF-I RTK inhibitors downregulated the tyrosine phosphorylation of the IGF-IR β-chain but not of the insulin receptor β-chain. In conclusion, the IGF-IR potently promotes growth and survival of MM cells. Therefore, interfering with the IGF-IR signaling pathway might be a suitable strategy to improve MM treatment.
14

Análogos da somatostatina na acromegalia: comparação da resposta clínica, laboratorial e do volume tumoral com a expressão dos subtipos dos receptores de somatostatina no tumor somatotrófico / Somatostatin analogs in acromegaly: comparison of clinic response, laboratory and tumor volume with expression of somatostatin receptor subtype in somatotroph tumor

Ana Paula Malinosk Casarini 13 August 2008 (has links)
Este estudo analisa a expressão dos subtipos de receptores da somatostatina (SSTR) em 39 adenomas secretores de GH. Em 19 pacientes acromegálicos, a resposta clínica, laboratorial e radiológica ao análogo da somatostatina (AS) octreotide-LAR foi comparada à expressão dos SSTR. O SSTR mais freqüentemente expresso foi o SSTR5, seguido pelos SSTR3, SSTR2, SSTR1 e SSTR4. O SSTR1 e SSTR2 foram mais expressos nos pacientes que normalizaram GH e IGF-I. Houve correlação positiva entre o grau de redução tumoral e a expressão dos SSTR1, SSTR2 e SSTR3. Portanto, AS específicos para os SSTR´s poderão contribuir para o tratamento de acromegálicos resistentes aos AS atualmente disponíveis / This study aimed to analyze the expression of somatostatin receptor subtypes (SSTR) in 39 GH-secreting pituitary adenomas. In 19 acromegalics the clinical, laboratorial and radiological responses to the somatostatin analog (SA) octreotide-LAR were compared to SSTR´s expression. The most expressed SSTR was SSTR5, followed by SSTR3, SSTR2, SSTR1 and SSTR4. SSTR1 and SSTR2 were more expressed in patients who achieved GH and IGF-I normalization. There was a positive correlation between the degree of tumor reduction with SSTR1, SSTR2 and SSTR3 expression. Therefore, the development of specific SA could contribute to treatment improvement in resistant acromegalics patients to available SA
15

Efeito da administração de octreotide, cabergolina e a associação de ambos nos níveis de ACTH e cortisol em pacientes com doença de Cushing: correlação da resposta clínica com a expressão tumoral dos receptores de dopamina  (DRD2) e de somatostatina (SSTR2 e SSTR5) / Effect of the administration of octreotide, cabergoline and the association of both on ACTH and cortisol levels in patients with Cushings disease: correlation of clinical response with tumoral expression of the dopamine (DRD2) and somatostatin (SSTR2 and SSTR5) receptors

Daniella de Jesus Patrick Carminatti Romanholi 31 August 2010 (has links)
Introdução: A doença de Cushing apresenta elevada morbimortalidade. Seu tratamento de escolha é a cirurgia transesfenoidal que possui resultados satisfatórios em cerca de 70% dos casos. Na doença persistente ou recorrente, reabordagem cirúrgica, radioterapia e adrenalectomia bilateral podem ser realizadas, porém, essas opções apresentam como desvantagens o desenvolvimento de hipopituitarismo e a dependência de terapia de reposição. Até o momento, nenhuma droga tem se mostrado eficaz no tratamento do corticotrofinoma. Os esquemas terapêuticos mais eficazes são os inibidores da esteroidogênese que não atuam no tumor hipofisário. Objetivos: avaliar o efeito do octreotide e da cabergolina administrados isoladamente e em associação nas concentrações urinárias de cortisol e plasmáticas de ACTH em pacientes com corticotrofinomas; correlacionar esse efeito com a expressão tumoral dos receptores SSTR2, SSTR5 e DRD2; correlacionar a expressão tumoral desses receptores através de RT-PCR quantitativa e imunohistoquímica; avaliar se o uso prévio dessas drogas altera a expressão desses receptores. Casuística e Métodos: grupo controle composto por 11 pacientes (10 mulheres e 1 homem) entre 21 e 43 anos sem tratamento prévio à neurocirurgia e um grupo tratado formado por 11 pacientes (2 homens e 9 mulheres) entre 22 e 53 anos que receberam o seguinte tratamento antes da cirurgia: coleta de três amostras de cortisol urinário e ACTH plasmático, seguida da introdução de octreotide 100 g, subcutâneo, 8/8h durante 30 dias e nova coleta de três amostras de cortisol urinário e ACTH plasmático. Em seguida, iniciou-se a cabergolina 0,5 mg via oral 3 vezes na semana durante 30 dias com nova coleta de três amostras de cortisol urinário e ACTH plasmático. A seguir, o octreotide era associado por mais 30 dias com nova coleta de três amostras de cortisol urinário e ACTH plasmático. Resultados: Os valores de cortisol urinário apresentaram queda significante após o uso de cabergolina isolada (P = 0,016) e em associação ao octreotide (P = 0,012). A eficácia do tratamento combinado não foi maior que a da cabergolina isolada. Os valores de ACTH plasmático não revelaram diferença significante durante o tratamento e não se correlacionaram com os valores de cortisol. A média de expressão do mRNA do gene DRD2 foi maior no grupo tratado (1,170 ± 0,417) quando comparada ao grupo controle (0,776 ± 0,252) (P = 0,036). Houve dissociação entre os conteúdos de mRNA e da proteína desse receptor. Não foi possível analisar a expressão do mRNA do gene SSTR5, pois o tratamento das amostras com DNAse causou degradação do RNA. A imunorreatividade para SSTR5 esteve presente em todos os pacientes e não foi alterada pelo tratamento prévio. Não houve diferença estatística na expressão do gene SSTR2 entre os grupos controle (1,253 ± 0,511) e tratado (1,267 ± 0,386) bem como diferença significante da imunoexpressão do SSTR2 entre os grupos. Houve correlação entre os conteúdos de mRNA e da proteína desse receptor (P = 0,021). Não houve correlação entre a expressão dos receptores analisados e a resposta ao octreotide e à cabergolina isoladamente ou em associação. Conclusões: a cabergolina isolada representa opção terapêutica na doença de Cushing persistente ou recorrente. A associação de octreotide na dose estudada por 30 dias não foi mais eficiente em reduzir o cortisol urinário. A resposta a essas drogas não está relacionada à expressão dos receptores SSTR2, SSTR5 e DRD2 / Introduction: The Cushings disease presents high morbimortality. Its treatment of choice is transsphenoidal surgery which has satisfactory results in about 70% of cases. In persistent or recurrent disease, a second transsphenoidal surgery, radiotherapy and bilateral adrenalectomy can be carried through, however, these options present disadvantages as development of hypopituitarism and lifelong dependence on hormone replacement therapy. Presently, no drug has shown efficacy in corticotrophinomas treatment. The most efficient agents are the inhibitors of steroidogenesis which have no effect at pituitary tumor. Objectives: To evaluate isolated octreotide and cabergoline effects and their association on plasma ACTH and urinary cortisol in Cushings disease patients, to correlate this effect with tumoral expression of SSTR2, SSTR5 and DRD2 receptors; to correlate tumoral expression of these receptors by quantitative RT-PCR and immunohistochemistry; to evaluate whether these drugs modifies these receptors expression. Patients and methods: control group with 11 patients (10 women and 1 man) between 21 and 43 years who underwent pituitary surgery with no prior treatment and a treated group with 11 patients (2 men and 9 women) between 22 and 53 years that received the following treatment before surgery: : after three baseline urinary cortisol samples and one plasma ACTH sample, patients received octreotide 100 g, subcutaneous 8/8h for 30 days collecting three urinary cortisol samples and one plasma ACTH. After that, cabergoline was introduced 0,5 mg 3x/week for 30 days collecting three urinary cortisol samples and one plasma ACTH sample. Then, octreotide was associated to cabergoline for another 30 days followed by three urinary cortisol and one plasma ACTH sample. Results: Urinary cortisol concentrations significantly decreased after isolated and combined cabergoline use (P = 0,016 and P = 0,012, respectively). Combined treatment efficacy was not greater than isolated cabergoline administration. Plasma ACTH did not change statistically during treatment and did not correlate with urinary cortisol. The average of DRD2 gene expression was higher in control group (0,776 ± 0,252) in relation to treated group (1,170 ± 0,417) (P = 0,036). It had dissociation between mRNA and protein contents of this receptor. SSTR5 gene mRNA expression was not analyzed due to RNA degradation after DNAse tissue treatment. SSTR5 immunoreactivity was present in all patients and it was not modified by previous treatment. No statistic difference was observed between SSTR2 gene expression in control group (1,253 ± 0.511) and in treated group (1,267 ± 0,386). There was no significant difference in SSTR2 immunoexpression between groups. It had correlation between the mRNA and protein contents of this receptor (P = 0.021). No significant relationship was found between hormonal response to isolated and combined therapy and receptors mRNA expression levels. Conclusions: cabergoline represents therapeutical option in persistent or recurrent Cushings disease. Octreotide-cabergoline association in the studied dosage and for the period of 30 days was not more efficient in eliciting urinary cortisol reduction. The responsiveness to these drugs did not correlate to SSTR2 and DRD2 mRNA expression
16

Small Cell Variant of Medullary Thyroid Carcinoma: A Possible Treatment

Sherret, John, Alomari, Mohammad, Coleman, Joshua, Hamati, Agnes 20 July 2020 (has links)
Small cell variant of medullary thyroid carcinoma is an extremely rare histologic entity with a paucity of data. As such, there is a lack of literature and clinical experience regarding this disease. In this report, we examine a case of small cell variant of medullary thyroid carcinoma that presented with intractable nausea, vomiting and diarrhea. While these symptoms were essentially refractory to the standard symptomatic treatment, further laboratory analysis revealed dramatically elevated calcitonin levels and mildly raised thyroid-stimulating hormone levels. Interestingly, repletion of thyroid hormone and treatment with lanreotide resulted in an abatement of our patient's symptoms. This temporal clinical improvement highly suggests a potential role involving thyroid-stimulating hormone and calcitonin levels in the pathogenesis of this disease, and consequently suggests a role for thyroxine in treating the associated gastrointestinal symptoms.
17

Tumores indutores de osteomalácia: diagnóstico, caracterização tumoral e avaliação evolutiva em longo prazo de nove pacientes / Tumor-induced osteomalacia: diagnosis, tumor characterization, and clinical evaluation in nine patients over a long-term period

Ferraz, Marcela Paula 14 April 2016 (has links)
INTRODUÇÃO: Tumores indutores de osteomalácia (TIOs) são raros, geralmente apresentam origem mesenquimal, têm produção excessiva de fosfatoninas sendo a mais comum o FGF23 (Fibroblast Growth Factor 23) que, em níveis elevados, provoca osteomalácia hipofosfatêmica. A cura dos TIOs envolve a remoção completa do tumor, o que torna essencial sua localização. OBJETIVOS: (1) caracterizar nove pacientes com TIO ao diagnóstico e avaliá-los evolutivamente em longo prazo; (2) avaliar a eficácia da cintilografia com Octreotida (Octreoscan®) e a da cintilografia de corpo inteiro com Mibi (MIBI) na detecção dos TIOs. MÉTODOS: O acompanhamento dos pacientes consistiu na avaliação clínica, na avaliação laboratorial com ênfase no metabolismo ósseo e na realização de exames de imagem para caracterização das deformidades esqueléticas. Para a localização dos TIOs, os pacientes foram submetidos a exames de Octreoscan®, MIBI, ressonância magnética (RM) e tomografia computadorizada (TC). RESULTADOS: O período de observação dos pacientes variou de dois a 25 anos. Ao diagnóstico, todos exibiam fraqueza muscular, dores ósseas e fraturas de fragilidade. Em relação à avaliação laboratorial, apresentavam: hipofosfatemia com taxa de reabsorção tubular de fosfato reduzida, fosfatase alcalina aumentada e níveis elevados de FGF23. O Octreoscan® permitiu a identificação dos TIOs nos nove pacientes e o MIBI possibilitou a localização dos TIOs em seis pacientes, sendo que ambos os exames foram concordantes entre si e com os exames topográficos (RM ou TC). Os achados histopatológicos das lesões dos nove pacientes confirmaram tratar-se de oito tumores mesenquimais fosfatúricos (PMTs) benignos e um PMT maligno. Após a primeira intervenção cirúrgica para a remoção dos TIOs, quatro pacientes encontram-se em remissão da doença e cinco evoluíram com persistência tumoral. Dos cinco, quatro foram reoperados e um aguarda nova cirurgia. Dos que foram reoperados, um paciente se mantém em remissão da doença, um foi a óbito por complicações clínicas, uma teve doença metastática e o último apresentou recidiva tumoral três anos após a segunda cirurgia. Deformidades ósseas graves foram observadas nos pacientes cujo diagnóstico e/ou tratamento clínico foram tardios. O tratamento da osteomalácia foi iniciado com fosfato e perdurou até a ressecção tumoral, tendo sido reintroduzido nos casos de persistência/recidiva tumoral. Quatro pacientes que fizerem uso regular desse medicamento por mais de seis anos evoluíram com hiperparatireoidismo terciário (HPT). CONCLUSÕES: O estudo revelou que tanto o Octreoscan® como o MIBI foram capazes de localizar os TIOs. Por isso, incentivamos a realização do MIBI nos locais onde o Octreoscan® não for disponível. Uma equipe experiente é indispensável para o sucesso cirúrgico visto que os tumores, embora benignos, costumam ser infiltrativos. Recomendamos o seguimento por tempo indeterminado em função do risco de recidiva tumoral. Assim como o FGF23, consideramos o fósforo um excelente marcador de remissão, persistência e recidiva dos TIOs. O diagnóstico e o tratamento precoce são fundamentais para a melhora dos sintomas podendo minimizar as deformidades esqueléticas e as sequelas ósseas. O uso prolongado do fosfato no tratamento da osteomalácia hipofosfatêmica foi associado ao desenvolvimento do HPT / BACKGROUND: Tumor-induced osteomalacia (TIO) is rare. The tumor usually has mesenchymal origin and produces excessive phosphatonins, most commonly FGF23 (Fibroblast Growth Factor 23), which at high levels causes hyphophostatemic osteomalacia. The cure for TIO is achieved through complete removal of the tumor. It is therefore essential identify its location. OBJECTIVES: (1) to characterize nine patients with TIO at diagnosis and to evaluate their follow-up over a long-term period; (2) to evaluate the efficacy of whole-body scintigraphy 111In-octreotide (Octreoscan®) and 99mTc-sestamibi (MIBI) in TIO detection. METHODS: Evaluations consisted of clinical and laboratory testing of bone metabolism and imaging to characterize skeletal deformities. To locate TIO, patients underwent Octreoscan®, MIBI, magnetic resonance (MRI), and computed tomography (TC). RESULTS: Patients were followed-up from two to 25 years. At diagnosis, all patients presented with muscle weakness, bone pain and fragility fractures. Laboratorial evaluation revealed hypophosphatemia with reduced tubular reabsorption of phosphate, increased alkaline phosphatase, and high levels of FGF23. TIO was identified in nine patients through Octreoscan® and in six patients through MIBI. Results of both types of scintigraphies matched one another as well with topographic examination (MR or CT). Histopathological findings of the lesions in the nine patients confirmed the existence of eight benign phosphaturic mesenchymal tumors (PMTs) and one malign PMT. After the first surgery for tumor resection, four patients were in remission, whereas five revealed tumoral persistence. Four of the latter five were re-operated, and one is still waiting for another surgery. Of those four patients, one became in remission, one died of clinical complications, one disclosed metastatic disease, and the last one had tumoral recurrence three years after the second surgery. Severe bone deformations were observed in patients whose diagnosis and/or clinical treatment were delayed. Osteomalacia treatment was initiated with oral phosphate, which continued until tumor resection. In case of tumor persistence or recurrence, oral phosphate was reintroduced. Four patients treated with this medication regularly for six years or more developed tertiary hyperparathyroidism (HPT). CONCLUSIONS: The present study revealed that Octreoscan® and MIBI were able to locating TIO. Therefore, we suggest that MIBI should be encouraged in places where Octreoscan® is not available. An expert team of surgeons is essential to the success of TIO\'s treatment, because of their infiltrative, albeit benign nature. Long-term follow-up is important due to the risk of tumor recurrence. Along with FGF23, phosphorous was considered an excellent hallmarker of TIO remission, persistence and recurrence. Early diagnosis and treatment are essential to improve symptoms and minimize skeletal deformities and skeletal disabilities. Long-term treatment of osteomalacia with oral phosphate was associated with the development of HPT
18

Neue medikamentöse Therapiestrategien beim Pankreaskarzinom

Wenger, Frank Axel 16 January 2003 (has links)
Die Mehrzahl der Patienten mit einem duktalen Pankreaskarzinom weist bei Diagnosestellung ein fortgeschrittenes Tumorstadium auf. Da die Chemo- und die Strahlentherapie nur geringe Ansprechraten bei gleichzeitig starken Nebenwirkungen zeigen, ist die Entwicklung neuer nebenwirkungsarmer Therapiekonzepte erforderlich. Zur Evaluierung neuer medikamentöser Behandlungskonzepte etablierten wir das Tumordell eines N-Nitrosobis-2-oxopropylamin (BOP)-induzierten duktalen Pankreaskarzinoms des Syrischen Hamsters, welches morphologisch und biologisch dem humanen Pankreaskarzinom sehr ähnlich ist. Um fortgeschrittene Tumorstadien zu simulieren hoben wir die in diesem Tiermodell auftretende Lebermetastasierungsrate von 30-35% auf 90% durch eine diätetische Modifikation an, indem der Rohfettanteil von 3,5% im Hamsterstandardfutter auf 21,4% erhöht wurde. Die führenden Komponenten waren dabei Linolsäure und Linolensäure. Da die gesteigerte Lebermetastasierung durch die Anhebung des Rohfettanteils bedingt war und eine Steigerung des oxidativen Stresses durch Nitrosamine, wie BOP, bekannt ist, untersuchten wir ferner den Einfluß auf die intra- und extrametastatische Lipidperoxidation. Unter der Therapie mit dem Somatostatin-Analogon Octreotid und dem Östrogenantagonisten Tamoxifen zeigte sich, daß Tamoxifen keinen Einfluß auf das Wachstum und die Lebermetastasierung hat. Hingegen verringerte Octreotid in Einzel- und Kombinationstherapie gleichermaßen das Lebermetastasenwachstum. Darüberhinaus führte Octreotid bei gleichzeitiger Hochfetternährung zu einer Erniedrigung der extrametastatischen und einer Erhöhung der intrametastatischen hepatischen Lipidperoxidation. Über diese beiden Mechanismen führt Octreotid möglicherweise zu einer Inhibition des Wachstums der Lebermetastasen. Hierbei scheint es sich nicht um einen rezeptorvermittelten Effekt handeln, da in metastasenfreien Leberanteilen keine Somatostatinrezeptoren nachweisbar waren. Demgegenüber könnte es sich bei der Octreotid-bedingten intrametastatischen Steigerung der Lipidperoxidation um einen direkten, rezeptorvermittelten Effekt handeln, da intrametastatisch Somatostatinrezeptoren nachgewiesen wurden. Unter der Therapie mit Vitamin A und E wurde die Lebermetastasierung beim Pankreaskarzinom erniedrigt. Biochemisch war unter der Behandlung mit den Vitaminen A, C und E die Aktivität der antioxidativen Schutzenzyme GSHPX und SOD erhöht, sowie die hepatisch Lipidperoxidation (TBARS) intra- und extrametastatisch erniedrigt. Ferner untersuchten wir den Einfluß der hochselektiven Cyclooxigenase-II- (Celebrex) und der 5-Lipoxygenase-Inhibition (Zyflo) des Eicosanoidstoffwechsels auf das Tumorwachstum des Pankreaskarzinoms. Während die Einzeltherapie mit Celebrex oder Zyflo keinen Einfluß auf die Inzidenz, Anzahl oder Größe von Lebermetastasen hatte, wurden alle 3 Parameter durch die Kombinationstherapie erniedrigt. Darüberhinaus war die hepatische Aktivität der Lipidperoxidations-Schutzenzyme intrametastatisch unter der Kombinationstherapie nicht erhöht. Dies führte zu einer Steigerung der intrametastatischen Lipidperoxidation, die wahrscheinlich für Membranschäden von Metastasenzellen mitverantwortlich ist, und über einen Verlust von Zellintegrität zum Zelltod führt. / At the time of diagnosis the majority of patients with ductal pancreatic cancer suffers from advanced tumor stages. Since present adjuvant therapies show strong side-effects and only decrease tumour growth in very few patients, the development of new therapeutic concepts seems urgent. In order to evaluate new therapeutic strategies we established a tumour model of N-nitrosobis-2-oxopropylamin (BOP) induced ductal pancreatic cancer in Syrian Hamster, which is equal to human cancer in morphological and biological aspects. Accordingly we increased the incidence of liver metastasis from 30-35% to 90% by diatetic modification elevating raw fat content from 3,5% zu 21,4% with important components linolenic and linol acid. Furthermore we evaluated the impact of increased raw fat content and oxidative stress, caused by nitrosamines, on intra- and extrametastatic lipidperoxidation. Evaluating the effect of the somatostatin analogue Octreotide and the estrogen antagonist Tamoxifen we observed that Tamoxifen did neither influence tumour growth nor liver metastasis while Octreotide decreased liver metastasis in single and combined therapy. Moreover Octreotide significantly decreased extrametastatic lipidperoxidation and increased intrametastatic lipidperoxidation. Probably inhibition of growth of liver metastasis was caused by these mechanisms. This effect seems not to be mediated by somatostatin receptors since we did not detect any receptors in non-metastatic hepatic tissue. However, intrametastatic increase of lipidperoxidation might directly be receptor-mediated, since we proved somatostatin receptors in liver metastasis. Therapy with Vitamine A and E decreased liver metastasis in pancreatic cancer. Biochemically activity of lipidperoxidation protective enzymes GSHPX and SOD was increased by Vitamine A, C and E while hepatic lipidperoxidation was decreased intra- and extrametastically. Furthermore we analysed the impact of selective cyclooxigenase-II- (Celebrex) and 5-lipoxygenase-inhibition (Zyflo) of eicosanoid metabolism on tumor growth in. While single therapy with Celebrex or Zyflo did not influence incidence, number or size of liver metastasis, these parameters were decreased by combined therapy. Moreover hepatic activity of lipidperoxidation protective enzymes was not increased intrametastatically by combined therapy. Thus intrametastatic lipidperoxidation increased and probably caused damage of membranes and apoptosis of metastatic cells.
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Análise da expressão da filamina A nos tumores hipofisários e suas implicações clínicas e terapêuticas / Analysis of filamin A expression in pituitary tumors and its clinical and therapeutic correlations

Sickler, Thaís de Paula 23 February 2018 (has links)
A filamina A (FLNA) é uma proteína de citoesqueleto com diversas funções, dentre as quais estão motilidade celular e ancoragem de receptores de membrana. A alteração de sua expressão foi anteriormente descrita em diversos tipos de neoplasia. Em tumores hipofisários, demonstrou-se que sua expressão se correlacionou à expressão de receptores de dopamina tipo 2 (DRD2) em prolactinomas, e com a sinalização intracelular do receptor de somatostatina tipo 2 (SSTR2) após ativação por agonista, em somatotropinomas. Neste estudo, avalariam-se a expressão da FLNA, DRD2, SSTR2 e SSTR5 em diversos tumores hipofisários: prolactinomas, somatotropinomas, corticotropinomas e adenomas clinicamente não funcionantes (ACNF). Avaliou-se também a correlação entre a expressão da FLNA e resposta aos tratamentos medicamentosos, com agonista dopaminérgico (AD) ou com ligantes do receptor de somatostatina (LRS), e entre FLNA e as características de invasividade e/ou agressividade tumorais. Houve correlação entre a expressão de FLNA e a expressão de DRD2 e, entre FLNA e a resposta ao AD, nos ACNFs. Nos corticotropinomas, houve correlação entre a expressão da FLNA e critérios de invasividade tumoral. Portanto, o papel da FLNA nos tumores hipofisários pode depender do tipo celular implicado. Além disso, o envolvimento da FLNA nos mecanismos de resistência aos medicamentos utilizados nos tumores hipofisários, AD ou LRS, não deve estar relacionado apenas à sua ação na ancoragem e reciclagem dos receptores DRD2 e SSTRs, mas também à sua ação na motilidade celular, propiciando caratecterísticas de invasividade / Filamin A (FLNA) is a cytoskeletal protein with a variety of functions, including cell motility and membrane receptor anchorage. Changes in FLNA expression has already been described in several types of neoplasia. In pituitary tumors, its expression has been shown to correlate with the expression of dopamine type 2 receptors (DRD2) in prolactinomas and with intracellular somatostatin type 2 receptor (SSTR2) signaling after agonist activation in somatotropinomas. The expression of FLNA, DRD2, SSTR2 and SSTR5 in different pituitary tumors: prolactinomas, somatotrophinomas, corticotrophinomas and clinically nonfunctioning adenomas (CNFA) were evaluated. We also correlate FLNA expression to sensibility to drug treatments with dopamin agonists (DA) or somatostatin receptor ligands (SRL), and to tumor invasiveness and/or aggressiveness. Positive correlation between FLNA expression and DRD2 expression and between FLNA and DA response were found in CNFA. In corticotrophinomas, there was correlation between FLNA expression and tumor invasiveness. Therefore, the role of FLNA in pituitary tumors seems to depend on the cell type involved. Additionally, FLNA involvement in the mechanisms of drug (DA or SRL) resistance in pituitary tumors could not be related only to its action in the anchoring and recycling of DRD2 and SSTR receptors, but also to its action on cellular motility and invasiveness
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Tumores indutores de osteomalácia: diagnóstico, caracterização tumoral e avaliação evolutiva em longo prazo de nove pacientes / Tumor-induced osteomalacia: diagnosis, tumor characterization, and clinical evaluation in nine patients over a long-term period

Marcela Paula Ferraz 14 April 2016 (has links)
INTRODUÇÃO: Tumores indutores de osteomalácia (TIOs) são raros, geralmente apresentam origem mesenquimal, têm produção excessiva de fosfatoninas sendo a mais comum o FGF23 (Fibroblast Growth Factor 23) que, em níveis elevados, provoca osteomalácia hipofosfatêmica. A cura dos TIOs envolve a remoção completa do tumor, o que torna essencial sua localização. OBJETIVOS: (1) caracterizar nove pacientes com TIO ao diagnóstico e avaliá-los evolutivamente em longo prazo; (2) avaliar a eficácia da cintilografia com Octreotida (Octreoscan®) e a da cintilografia de corpo inteiro com Mibi (MIBI) na detecção dos TIOs. MÉTODOS: O acompanhamento dos pacientes consistiu na avaliação clínica, na avaliação laboratorial com ênfase no metabolismo ósseo e na realização de exames de imagem para caracterização das deformidades esqueléticas. Para a localização dos TIOs, os pacientes foram submetidos a exames de Octreoscan®, MIBI, ressonância magnética (RM) e tomografia computadorizada (TC). RESULTADOS: O período de observação dos pacientes variou de dois a 25 anos. Ao diagnóstico, todos exibiam fraqueza muscular, dores ósseas e fraturas de fragilidade. Em relação à avaliação laboratorial, apresentavam: hipofosfatemia com taxa de reabsorção tubular de fosfato reduzida, fosfatase alcalina aumentada e níveis elevados de FGF23. O Octreoscan® permitiu a identificação dos TIOs nos nove pacientes e o MIBI possibilitou a localização dos TIOs em seis pacientes, sendo que ambos os exames foram concordantes entre si e com os exames topográficos (RM ou TC). Os achados histopatológicos das lesões dos nove pacientes confirmaram tratar-se de oito tumores mesenquimais fosfatúricos (PMTs) benignos e um PMT maligno. Após a primeira intervenção cirúrgica para a remoção dos TIOs, quatro pacientes encontram-se em remissão da doença e cinco evoluíram com persistência tumoral. Dos cinco, quatro foram reoperados e um aguarda nova cirurgia. Dos que foram reoperados, um paciente se mantém em remissão da doença, um foi a óbito por complicações clínicas, uma teve doença metastática e o último apresentou recidiva tumoral três anos após a segunda cirurgia. Deformidades ósseas graves foram observadas nos pacientes cujo diagnóstico e/ou tratamento clínico foram tardios. O tratamento da osteomalácia foi iniciado com fosfato e perdurou até a ressecção tumoral, tendo sido reintroduzido nos casos de persistência/recidiva tumoral. Quatro pacientes que fizerem uso regular desse medicamento por mais de seis anos evoluíram com hiperparatireoidismo terciário (HPT). CONCLUSÕES: O estudo revelou que tanto o Octreoscan® como o MIBI foram capazes de localizar os TIOs. Por isso, incentivamos a realização do MIBI nos locais onde o Octreoscan® não for disponível. Uma equipe experiente é indispensável para o sucesso cirúrgico visto que os tumores, embora benignos, costumam ser infiltrativos. Recomendamos o seguimento por tempo indeterminado em função do risco de recidiva tumoral. Assim como o FGF23, consideramos o fósforo um excelente marcador de remissão, persistência e recidiva dos TIOs. O diagnóstico e o tratamento precoce são fundamentais para a melhora dos sintomas podendo minimizar as deformidades esqueléticas e as sequelas ósseas. O uso prolongado do fosfato no tratamento da osteomalácia hipofosfatêmica foi associado ao desenvolvimento do HPT / BACKGROUND: Tumor-induced osteomalacia (TIO) is rare. The tumor usually has mesenchymal origin and produces excessive phosphatonins, most commonly FGF23 (Fibroblast Growth Factor 23), which at high levels causes hyphophostatemic osteomalacia. The cure for TIO is achieved through complete removal of the tumor. It is therefore essential identify its location. OBJECTIVES: (1) to characterize nine patients with TIO at diagnosis and to evaluate their follow-up over a long-term period; (2) to evaluate the efficacy of whole-body scintigraphy 111In-octreotide (Octreoscan®) and 99mTc-sestamibi (MIBI) in TIO detection. METHODS: Evaluations consisted of clinical and laboratory testing of bone metabolism and imaging to characterize skeletal deformities. To locate TIO, patients underwent Octreoscan®, MIBI, magnetic resonance (MRI), and computed tomography (TC). RESULTS: Patients were followed-up from two to 25 years. At diagnosis, all patients presented with muscle weakness, bone pain and fragility fractures. Laboratorial evaluation revealed hypophosphatemia with reduced tubular reabsorption of phosphate, increased alkaline phosphatase, and high levels of FGF23. TIO was identified in nine patients through Octreoscan® and in six patients through MIBI. Results of both types of scintigraphies matched one another as well with topographic examination (MR or CT). Histopathological findings of the lesions in the nine patients confirmed the existence of eight benign phosphaturic mesenchymal tumors (PMTs) and one malign PMT. After the first surgery for tumor resection, four patients were in remission, whereas five revealed tumoral persistence. Four of the latter five were re-operated, and one is still waiting for another surgery. Of those four patients, one became in remission, one died of clinical complications, one disclosed metastatic disease, and the last one had tumoral recurrence three years after the second surgery. Severe bone deformations were observed in patients whose diagnosis and/or clinical treatment were delayed. Osteomalacia treatment was initiated with oral phosphate, which continued until tumor resection. In case of tumor persistence or recurrence, oral phosphate was reintroduced. Four patients treated with this medication regularly for six years or more developed tertiary hyperparathyroidism (HPT). CONCLUSIONS: The present study revealed that Octreoscan® and MIBI were able to locating TIO. Therefore, we suggest that MIBI should be encouraged in places where Octreoscan® is not available. An expert team of surgeons is essential to the success of TIO\'s treatment, because of their infiltrative, albeit benign nature. Long-term follow-up is important due to the risk of tumor recurrence. Along with FGF23, phosphorous was considered an excellent hallmarker of TIO remission, persistence and recurrence. Early diagnosis and treatment are essential to improve symptoms and minimize skeletal deformities and skeletal disabilities. Long-term treatment of osteomalacia with oral phosphate was associated with the development of HPT

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