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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

Rastreamento de mutações nos genes VHL, SDHB e SDHD em pacientes portadores de feocromocitoma ou também, paraganglioma esporádico / Mutation screening in the VHL, SDHB and SDHD genes in patients with sporadic pheochromocytoma and/or paraganglioma

Loureiro, Vanessa Correia 06 March 2007 (has links)
Os feocromocitomas são tumores neuroendócrinos constituídos de células cromafins secretoras de catecolaminas e neuropeptídeos diversos, cuja manifestação clínica mais comum é a hipertensão. Doze a 24% dos tumores aparentemente esporádicos, apresentam mutações germinativas em genes até então associados a síndromes herdadas, como, RET, VHL, SDHB e SDHD. A doença de von Hippel-Lindau é causada por mutações no gene VHL. As proteínas codificadas pelos genes SDHB e SDHD fazem parte do complexo mitocondrial II e da cadeia aeróbica de transporte de elétrons. O objetivo deste projeto de pesquisa foi o rastreamento de mutações nos genes VHL, SDHB e SDHD em pacientes portadores de feocromocitoma ou, também, paraganglioma esporádicos acompanhados no Serviço de Endocrinologia do Hospital das Clínicas da FMUSP. Todos os exons dos três genes estudados foram amplificados por PCR e analisados por dHPLC. Os amplicons que apresentaram cromatogramas suspeitos ao dHPLC foram submetidos ao seqüenciamento automático. Nenhuma mutação foi encontrada no gene VHL, apenas dois polimorfismos previamente descritos no exon 1, c. -77 C>T em dois pacientes e c - 195 G>A em 58,6% do total de alelos dos pacientes estudados. No gene SDHB foram encontrados dois polimorfismos previamente descritos (c. 201-36 G>T e c.487 T>C) em quatro pacientes, uma mutação silenciosa não descrita (c.540 G>A) e uma mutação previamente descrita em portadores de feocromocitoma (c. 293 G>A). Um mesmo paciente apresentou a mutação silenciosa c.540 G>A e o polimorfismo c.201-36 G>T. No gene SDHD foram encontrados dois polimorfismos descritos (c.204 C>T e c.315-32 T>C) em um paciente cada, uma variante alélica descrita na literatura na região 3\' não codificante cuja freqüência nunca foi estudada em outras populações (c.*612 C>T) e duas substituições nunca descritas na região 3\' não codificante (c.*799 T>C e c.*803 A>G). As variantes c.*612 C>T e c.*799 T>C foram detectadas em apenas um paciente cada e não foram encontradas em 200 alelos de controles normais estudados. A variante c.*803 A>G foi encontrada em nove de 76 alelos dos 38 pacientes (11,8%) e em cinco de 200 alelos de 100 controles não afetados (2,5%), sendo, portanto, um polimorfismo significativamente mais freqüente entre os portadores de feocromocitoma ou paraganglioma. Dentre os sete pacientes portadores do polimorfismo c.*803 A>G, três pacientes heterozigotos para este polimorfismo apresentaram um segundo polimorfismo no gene SDHD, sendo que um desses pacientes também apresentava uma mutação no gene SDHB. Dentre os demais quatro pacientes, dois apresentavam o polimorfismo c.*803 A>G em homozigose. Este polimorfismo ocorre no nucleotídeo localizado na posição -1 imediatamente 5\' ao Sítio de Clivagem do pré-mRNA para que ocorra a inserção da cauda Poli(A), fundamental para a estabilidade do mRNA. A substituição da base A pela base G muito provavelmente apresenta uma repercussão funcional, pois a base A na posição -1 é considerada como a mais eficiente na promoção da clivagem do pré-mRNA, enquanto a base G é considerada a menos eficiente (ordem de eficiência de clivagem A > U > C > G). Desta forma, a possibilidade desse polimorfismo conferir susceptibilidade ao desenvolvimento do feocromocitoma e do paraganglioma não está descartada, sendo provável que outros eventos genéticos sejam necessários para promover a tumorigênese. Em conclusão, esse estudo evidenciou uma baixa freqüência de mutações nas regiões codificantes dos genes VHL (mutações não detectadas), SDHB (5,2%) e SDHD (mutações não detectadas) nessa série de pacientes com feocromocitomas e paragangliomas esporádicos, porém, encontrou um polimorfismo na região 3\' não codificante do gene SDHD significativamente mais freqüente nos portadores desses tumores que em indivíduos controles não afetados, e que, por suas características, pode estar relacionado à etiopatogenia do feocromocitoma e do paraganglioma. / Pheochromocytomas are neuroendocrine tumors composed of chromaffin cells that produce and secrete catecholamines as well as a variety of neuropeptides, whose most common clinical manifestation is arterial hypertension. Twelve to 24% of the apparently sporadic pheochromocytomas, present germline mutations in genes previously associated to inherited familiar syndromes, such as, RET, VHL, SDHB e SDHD. The von Hippel-Lindau (VHL) disease occurs upon the VHL gene mutation - a tumor suppressor gene whose product encodes complexes with other proteins leading proteic substracts to the proteolysis. The proteins encoded by the SDHD and SDHB genes are parts of the complex mitochondrial II, as well as the aerobic chain of the electron transport. The aim of the present study was the screening of mutations in the VHL, SDHB and SDHD genes in patients harboring sporadic pheochromocytoma and/or paraganglioma, followed by the Endocrinology Service of Hospital das Clínicas of the University of São Paulo School of Medicine. All the three studied gene exons were amplified by polymerase chain reaction (PCR) and were analyzed by dHPLC, which was the method used for screen mutations. The samples with altered eluting progress were directly sequenced. No mutations were found in the VHL gene, only two polymorphisms previously described in the exon 1, c. -77 C>T in two patients and c - 195 G> in 58.6% out of the total alleles of the studied patients. Two polymorphisms previously described (c. 201-36 G>T and c.487 T>C) in the SDHB gene were found in four patients, as well as silent mutation not yet described (c.540 G>A) and a mutation previously described in patients with pheochromocytoma (c. 293 G>A). A particular patient presented the silent mutation c.540 G>A and the polymorphism c.201-36 G>T. In the SDHD gene two polymorpfisms previously described (c.204 C>T and c.315-32 T>C) were found, one in each patient, as well as an allelic variant previously described in the 3\' non-coding region whose frequency has never been studied in other populations (c.*612 C>T) and two substitutions never described in the 3\' non-coding region (c.*799 T>C and c.*803 A>G). The variants c.*612 C>T and c.*799 T>C were detected in only one patient each and have not been found in 200 alleles of normal control subjects studied. The variant c.*803 A>G was found in nine out of 76 alleles from 38 patients (11.8%) and in five out of 200 alleles from 100 non-affected subjects (2.5%), being, then, a polymorphism significantly more frequent among patients with pheochromocytoma or paraganglioma. Among those seven patients with the polymorphism c.*803 A>G, three patients heterozygotous for the polymorphism presented a second polymorphism in the SDHD gene and one of those patients also presented a mutation in the SDHB gene. Out of the other four patients, two presented the polymorphism c.*803 A>G in heterozygosis. This polymorphism occurs in the nucleotide localized in the position -1 immediately 5\' to the site where the pre-mRNA is cleaved for the insertion of the poly(A) tail, which is essencial to the mRNA stability. The substitution of the A to the G probably presents a functional repercussion, because the A in the position -1 is considered as the most efficient nucleotide in the pre-mRNA cleavage promotion, while the G is considered the least efficient one (scale of cleavage efficiency A > U > C > G). Therefore, the possibility of this polymorphism be associated with susceptibility to the development of pheochromocytoma and paraganglioma is not discarded, being possible that other genetic events are necessary to promote tumorigenesis. In conclusion, this study evidenced a low frequency of mutations in the coding regions of the genes VHL (mutations not detected), SDHB (5,2%) and SDHD (mutations not detected) in this series of patients with sporadic pheochromocytomas and paragangliomas, however, a polymorphism significantly more frequent in patients harboring those tumors was found in the 3\' non-coding region of the SDHD gene and, for its specific characteristics, it can very well be related to the etiopathogenesis of the pheochromocytoma and paraganglioma
12

Rastreamento de mutações nos genes VHL, SDHB e SDHD em pacientes portadores de feocromocitoma ou também, paraganglioma esporádico / Mutation screening in the VHL, SDHB and SDHD genes in patients with sporadic pheochromocytoma and/or paraganglioma

Vanessa Correia Loureiro 06 March 2007 (has links)
Os feocromocitomas são tumores neuroendócrinos constituídos de células cromafins secretoras de catecolaminas e neuropeptídeos diversos, cuja manifestação clínica mais comum é a hipertensão. Doze a 24% dos tumores aparentemente esporádicos, apresentam mutações germinativas em genes até então associados a síndromes herdadas, como, RET, VHL, SDHB e SDHD. A doença de von Hippel-Lindau é causada por mutações no gene VHL. As proteínas codificadas pelos genes SDHB e SDHD fazem parte do complexo mitocondrial II e da cadeia aeróbica de transporte de elétrons. O objetivo deste projeto de pesquisa foi o rastreamento de mutações nos genes VHL, SDHB e SDHD em pacientes portadores de feocromocitoma ou, também, paraganglioma esporádicos acompanhados no Serviço de Endocrinologia do Hospital das Clínicas da FMUSP. Todos os exons dos três genes estudados foram amplificados por PCR e analisados por dHPLC. Os amplicons que apresentaram cromatogramas suspeitos ao dHPLC foram submetidos ao seqüenciamento automático. Nenhuma mutação foi encontrada no gene VHL, apenas dois polimorfismos previamente descritos no exon 1, c. -77 C>T em dois pacientes e c - 195 G>A em 58,6% do total de alelos dos pacientes estudados. No gene SDHB foram encontrados dois polimorfismos previamente descritos (c. 201-36 G>T e c.487 T>C) em quatro pacientes, uma mutação silenciosa não descrita (c.540 G>A) e uma mutação previamente descrita em portadores de feocromocitoma (c. 293 G>A). Um mesmo paciente apresentou a mutação silenciosa c.540 G>A e o polimorfismo c.201-36 G>T. No gene SDHD foram encontrados dois polimorfismos descritos (c.204 C>T e c.315-32 T>C) em um paciente cada, uma variante alélica descrita na literatura na região 3\' não codificante cuja freqüência nunca foi estudada em outras populações (c.*612 C>T) e duas substituições nunca descritas na região 3\' não codificante (c.*799 T>C e c.*803 A>G). As variantes c.*612 C>T e c.*799 T>C foram detectadas em apenas um paciente cada e não foram encontradas em 200 alelos de controles normais estudados. A variante c.*803 A>G foi encontrada em nove de 76 alelos dos 38 pacientes (11,8%) e em cinco de 200 alelos de 100 controles não afetados (2,5%), sendo, portanto, um polimorfismo significativamente mais freqüente entre os portadores de feocromocitoma ou paraganglioma. Dentre os sete pacientes portadores do polimorfismo c.*803 A>G, três pacientes heterozigotos para este polimorfismo apresentaram um segundo polimorfismo no gene SDHD, sendo que um desses pacientes também apresentava uma mutação no gene SDHB. Dentre os demais quatro pacientes, dois apresentavam o polimorfismo c.*803 A>G em homozigose. Este polimorfismo ocorre no nucleotídeo localizado na posição -1 imediatamente 5\' ao Sítio de Clivagem do pré-mRNA para que ocorra a inserção da cauda Poli(A), fundamental para a estabilidade do mRNA. A substituição da base A pela base G muito provavelmente apresenta uma repercussão funcional, pois a base A na posição -1 é considerada como a mais eficiente na promoção da clivagem do pré-mRNA, enquanto a base G é considerada a menos eficiente (ordem de eficiência de clivagem A > U > C > G). Desta forma, a possibilidade desse polimorfismo conferir susceptibilidade ao desenvolvimento do feocromocitoma e do paraganglioma não está descartada, sendo provável que outros eventos genéticos sejam necessários para promover a tumorigênese. Em conclusão, esse estudo evidenciou uma baixa freqüência de mutações nas regiões codificantes dos genes VHL (mutações não detectadas), SDHB (5,2%) e SDHD (mutações não detectadas) nessa série de pacientes com feocromocitomas e paragangliomas esporádicos, porém, encontrou um polimorfismo na região 3\' não codificante do gene SDHD significativamente mais freqüente nos portadores desses tumores que em indivíduos controles não afetados, e que, por suas características, pode estar relacionado à etiopatogenia do feocromocitoma e do paraganglioma. / Pheochromocytomas are neuroendocrine tumors composed of chromaffin cells that produce and secrete catecholamines as well as a variety of neuropeptides, whose most common clinical manifestation is arterial hypertension. Twelve to 24% of the apparently sporadic pheochromocytomas, present germline mutations in genes previously associated to inherited familiar syndromes, such as, RET, VHL, SDHB e SDHD. The von Hippel-Lindau (VHL) disease occurs upon the VHL gene mutation - a tumor suppressor gene whose product encodes complexes with other proteins leading proteic substracts to the proteolysis. The proteins encoded by the SDHD and SDHB genes are parts of the complex mitochondrial II, as well as the aerobic chain of the electron transport. The aim of the present study was the screening of mutations in the VHL, SDHB and SDHD genes in patients harboring sporadic pheochromocytoma and/or paraganglioma, followed by the Endocrinology Service of Hospital das Clínicas of the University of São Paulo School of Medicine. All the three studied gene exons were amplified by polymerase chain reaction (PCR) and were analyzed by dHPLC, which was the method used for screen mutations. The samples with altered eluting progress were directly sequenced. No mutations were found in the VHL gene, only two polymorphisms previously described in the exon 1, c. -77 C>T in two patients and c - 195 G> in 58.6% out of the total alleles of the studied patients. Two polymorphisms previously described (c. 201-36 G>T and c.487 T>C) in the SDHB gene were found in four patients, as well as silent mutation not yet described (c.540 G>A) and a mutation previously described in patients with pheochromocytoma (c. 293 G>A). A particular patient presented the silent mutation c.540 G>A and the polymorphism c.201-36 G>T. In the SDHD gene two polymorpfisms previously described (c.204 C>T and c.315-32 T>C) were found, one in each patient, as well as an allelic variant previously described in the 3\' non-coding region whose frequency has never been studied in other populations (c.*612 C>T) and two substitutions never described in the 3\' non-coding region (c.*799 T>C and c.*803 A>G). The variants c.*612 C>T and c.*799 T>C were detected in only one patient each and have not been found in 200 alleles of normal control subjects studied. The variant c.*803 A>G was found in nine out of 76 alleles from 38 patients (11.8%) and in five out of 200 alleles from 100 non-affected subjects (2.5%), being, then, a polymorphism significantly more frequent among patients with pheochromocytoma or paraganglioma. Among those seven patients with the polymorphism c.*803 A>G, three patients heterozygotous for the polymorphism presented a second polymorphism in the SDHD gene and one of those patients also presented a mutation in the SDHB gene. Out of the other four patients, two presented the polymorphism c.*803 A>G in heterozygosis. This polymorphism occurs in the nucleotide localized in the position -1 immediately 5\' to the site where the pre-mRNA is cleaved for the insertion of the poly(A) tail, which is essencial to the mRNA stability. The substitution of the A to the G probably presents a functional repercussion, because the A in the position -1 is considered as the most efficient nucleotide in the pre-mRNA cleavage promotion, while the G is considered the least efficient one (scale of cleavage efficiency A > U > C > G). Therefore, the possibility of this polymorphism be associated with susceptibility to the development of pheochromocytoma and paraganglioma is not discarded, being possible that other genetic events are necessary to promote tumorigenesis. In conclusion, this study evidenced a low frequency of mutations in the coding regions of the genes VHL (mutations not detected), SDHB (5,2%) and SDHD (mutations not detected) in this series of patients with sporadic pheochromocytomas and paragangliomas, however, a polymorphism significantly more frequent in patients harboring those tumors was found in the 3\' non-coding region of the SDHD gene and, for its specific characteristics, it can very well be related to the etiopathogenesis of the pheochromocytoma and paraganglioma
13

Further delineation of molecular alterations in adreno-medullary tumors /

Geli, Janos, January 2007 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 6 uppsatser.
14

DNA methylation and gene expression patterns in adrenal medullary tumors

Kiss, Nimrod G.B., January 2009 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2009. / Härtill 6 uppsatser.
15

Molekulárně biologická analýza feochromocytomu a paragangliomu. / Molecular biological analysis of pheochromocytoma and paraganglioma.

Musil, Zdeněk January 2019 (has links)
This work summarizes the results of a research inquiring into relatively rare neuroendocrine tumors - pheochromocytomas and paragangliomas (PHEO/PGL) These tumors may arise on a hereditary genetic predisposition basis. On that account we primarily focused on a genetic examination of patients with PHEO/PGL. Methods for diagnostics of changes in SDHD, SDHB and RET genes were implemented. The number of examined genes has been (and is still being) extended. Currently we are investigating these genes: ATRX, BRAF, CDH1, CDKN2A, CDKN2B, FGFR1, FH, FHIT, GNAS, HIF2A (EPAS1), H-RAS, IDH1, IDH2, KIF1Bß, KMT2D, K-RAS, MAML3, MAX, MDH2, MET, NF1, NGFR, N-RAS, PHD2/EGLN1, RET, SDHA, SDHAF2, SDHB, SDHC, SDHD, TERT, TMEM 127, TP53 and VHL, using next generation sequencing. The number of variations of the above mentioned genes is different (23%) in Czech patients with PHEO/PGL in comparison with some foreign studies (27%, 40%). This may be caused by geographical influences or selection of patients. PHEO/PGL occur mainly (75%) in a benign form. A malignant form may be indicated by the presence of chromaffin tissue in locations where these tumors do not usually occur - liver, lungs, bones. In our study we focused on characteristics indicating the malignancy, for example, the lower age of patients with the first manifestation...
16

Genetic analysis of pheochromocytoma and paraganglioma complicating cyanotic congenital heart disease / チアノーゼ性先天性心疾患に伴う褐色細胞腫及びパラガングリオーマの遺伝学的解析

Ogasawara, Tatsuki 23 January 2023 (has links)
京都大学 / 新制・課程博士 / 博士(医学) / 甲第24314号 / 医博第4908号 / 新制||医||1062(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 小林 恭, 教授 松田 文彦, 教授 柳田 素子 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
17

Apport de l'imagerie multimodale à l'étude de l'angiogenèse et du métabolisme des tumeurs liées aux mutations SDHB / In vivo multimodality imaging for the study of angiogenesis and metabolism in SDHB-mutated tumors

Lussey, Charlotte 25 November 2015 (has links)
Les phéochromocytomes et les paragangliomes (PCC/PGL) sont des tumeurs neuroendocrines rares qui se développent aux dépens de la médullosurrénale et des paraganglions sympathiques et parasympathiques. Près de 40% des patients ont une prédisposition génétique, et, à ce jour 13 gènes de prédisposition ont été identifiés. Les mutations du gène SDHB sont un facteur de risque de malignité et de mauvais pronostic qui conduisent à une perte de fonction de la succinate déshydrogénase (SDH), enzyme du complexe mitochondrial II. Il en résulte une accumulation intracellulaire de succinate responsable du phénomène dit de « pseudohypoxie » qui stimule la production de VEGF et donc l’angiogenèse, ainsi que l’expression du transporteur membranaire du glucose GLUT-1. Le surrisque de malignité liée à SDHB et l’absence de traitement curatif des formes métastatiques de PCC/PGL justifient l’élaboration d’un modèle murin permettant de mettre en place des essais précliniques. L’obtention d’un modèle murin prédisposé au PCC/PGL par mutation du gène Sdhb s’étant révélée infructueuse, notre équipe a finalement généré des cellules chromaffines Sdhb-/- immortalisées (imCC Sdhb-/-) dont l’implantation dans le coussinet adipeux sous-cutané (Fat-pad) de souris nudes NMRI a permis l’établissement du premier modèle de tumeurs porteuses d’une inactivation complète du gène Sdhb. La caractérisation phénotypique du modèle a été réalisée par imagerie multimodalité in vivo, comparativement à un groupe contrôle de souris ayant reçu des imCC non mutées (WT). L’angiogenèse tumorale évaluée par imagerie optique retrouve une expression des intégrines αvβ3 plus marquée dans le groupe Sdhb-/- avec une rétention du traceur prolongée 12 h après injection. L’IRM dynamique de contraste (IRM-DCE), montre un rehaussement tumoral global nettement plus important dans le modèle Sdhb-/-, que le post-traitement par le logiciel PhysioD3D permet d’attribuer à une augmentation du volume capillaire intratumoral. Sur le plan métabolique, la consommation globale de glucose mesurée par TEP au 18FDG est également plus marquée dans les tumeurs Sdhb-/-. Enfin, la spectroscopie par résonance magnétique (1H-MRS) a mis en évidence une accumulation de succinate dans les tumeurs Sdhb-/-, non retrouvée dans les tumeurs WT. Ce résultat a été confirmé par spectrométrie de masse et cette technique innovante de détection du succinate in vivo a été transférée avec succès en clinique pour l’exploration des patients porteurs de PCC/PGL. En conclusion, l’imagerie in vivo a permis de distinguer le phénotype des tumeurs Sdhb-/- de celui des WT, avec une néoangiogenèse, une microcirculation et un métabolisme glucidique augmentés. Ces résultats permettent de proposer des études précliniques de réponse précoce aux traitements. La détection de l’accumulation de succinate par 1H-MRS ouvre la possibilité d’un diagnostic « métabolique » préopératoire pour détecter les patients de mauvais pronostic. / Pheochromocytomas and paragangliomas (PCC/PGL) are rare neuroendocrine tumours that arise from chromaffin cells of the adrenal medulla, sympathetic and parasympathetic paraganglia respectively. Around 15% of PCC are malignant. SDHB mutations are associated with malignancy and poor prognosis. SDH deficiency leads to succinate accumulation that induces a cellular pseudohypoxic phenotype, promoting in particular VEGF and GLUT-1 expression and increasing angiogenesis and glucose metabolism. The high malignancy hazard associated with SDHB and the absence of curative treatment of metastatic forms of the disease make it essential to develop a mouse model for preclinical trials launching. The quest for a predisposed mouse model of Sdhb-deficient tumors being unsuccessful, Sdhb-/- and wild-type (WT) immortalized mouse chromaffin cells previously generated in the laboratory were propagated in the fat pad of NMRI nude mice, thereby providing the first pattern of Sdhb- deficient tumors. These mice were compared to a control group receiving non-mutated imCC (WT) and characterization was performed in vivo by multimodality imaging. Optical imaging assessing the tumor angiogenesis with Angiostamp®, an RGD fluorescent peptide, found an increased expression of integrins αvβ3 in the Sdhb-/- group 12 h after tracer injection. Dynamic contrast enhanced MRI (DCE-MRI) showed an overall tumor enhancement significantly higher in the Sdhb-/- model secondary to an increase of the tumor blood flow (F) and of the intratumoral capillary volume fraction (Vb) (compartmental analysis using PhysioD3D software). Metabolic imaging assessed by 18FDG-PET confirmed the expected high glucose consumption by Sdhb-/- tumors. Finally, magnetic resonance spectroscopy (1H-MRS) detected succinate accumulation in Sdhb-/- tumors and not in WT tumors. This result was confirmed by mass spectrometry and this innovative procedure for in vivo detection of succinate was translated into patients suffering from PCC/PGL. A succinate peak was specifically observed in SDHx-related PCC/PGL patients. In conclusion, these results show strong differences between Sdhb-/- and WT allografts and suggest that preclinical therapeutic studies could be implemented in this unique model of Sdhb-deficient tumour. Our noninvasive, highly sensitive and specific method allowing in vivo detection of succinate, the major biomarker of SDHx-mutated tumors was translated into clinical imaging.
18

Možnosti genetického vyšetření u pacientů s feochromocytomem a paragangliomem. / Possibilities of genetic testing in patients with pheochromocytoma and paraganglioma.

Turková, Hana January 2016 (has links)
1. Abstract Pheochromocytoma/ paraganglioma (FEO/PGL) may be developed on the basis of an inherited genetic mutation of different genes. They are associated with a high risk of developing of secondary hypertension, organ damage and metastatic disease that can be fatal. The aim was to focus on the possibility of genetic testing in patients with FEO/PGL, especially in patients with malignant tumors. The issue FEO/PGL, however, concerns not only the examination and assessment of risks arising therefrom, as well as other therapies and monitoring, including appropriate recommendations for clinical practice. We demonstrated a 20% incidence of cardiovascular (CV) complications before determining the final diagnosis of FEO/PGL, mainly arrhythmic, followed by complications of myocardial ischemia and accentuate atherosclerosis. Elevated levels of vitamin C and decreased levels of malondialdehyde (MDA) following the successful removal of the tumor demonstrated reduction of oxidative stress postoperatively. We found that early postoperative testing of levels of plasma metanephrines to confirm the success of surgical removal of FEO/PGL is already possible, since there was no significant correlation between plasma levels of metanephrines and postoperative examination interval. Distribution of frequency of metastatic...
19

Možnosti genetického vyšetření u pacientů s feochromocytomem a paragangliomem. / Possibilities of genetic testing in patients with pheochromocytoma and paraganglioma.

Turková, Hana January 2016 (has links)
1. Abstract Pheochromocytoma/ paraganglioma (FEO/PGL) may be developed on the basis of an inherited genetic mutation of different genes. They are associated with a high risk of developing of secondary hypertension, organ damage and metastatic disease that can be fatal. The aim was to focus on the possibility of genetic testing in patients with FEO/PGL, especially in patients with malignant tumors. The issue FEO/PGL, however, concerns not only the examination and assessment of risks arising therefrom, as well as other therapies and monitoring, including appropriate recommendations for clinical practice. We demonstrated a 20% incidence of cardiovascular (CV) complications before determining the final diagnosis of FEO/PGL, mainly arrhythmic, followed by complications of myocardial ischemia and accentuate atherosclerosis. Elevated levels of vitamin C and decreased levels of malondialdehyde (MDA) following the successful removal of the tumor demonstrated reduction of oxidative stress postoperatively. We found that early postoperative testing of levels of plasma metanephrines to confirm the success of surgical removal of FEO/PGL is already possible, since there was no significant correlation between plasma levels of metanephrines and postoperative examination interval. Distribution of frequency of metastatic...
20

Catecholamine metabolism in pheochromocytomas/paragangliomas due to pathogenic variants in HRAS and its association with clinical practice

Li, Minghao 25 January 2024 (has links)
Phäochromozytome und Paragangliome (PPGL) sind seltene neuroendokrine Tumore, die von Chromaffinzellen im Nebennierenmark (Phäochromozytome, PCC) oder vom extra-adrenalen Paraganglion (Paragangliome, PGL) ausgehen. Patienten mit PPGL zeigen in der Regel Anzeichen und Symptome, die mit der Biosynthese, Speicherung und Sekretion von Katecholaminen (Dopamin, Noradrenalin, Adrenalin) zusammenhängen. Der Katecholamin-Stoffwechsel bei PPGLs wird durch den genetischen Hintergrund bestimmt. Tumoren, die auf pathogene Varianten (PVs) in Genen zurückzuführen sind, die zur Aktivierung von Hypoxie-Signalwegen führen, sind nicht in der Lage, Epinephrin zu synthetisieren, während solche, die auf PVs in Genen zurückzuführen sind, die Kinase-Signalwege aktivieren, zur Epinephrin-Synthese befähigt sind. Dieser genetisch-biochemisch-klinische Phänotyp wurde in der klinischen Forschung nachgewiesen. Der Mechanismus, der der Regulierung der Katecholamin-Biosynthese durch Tumoren aufgrund von PVs in Kinase-Signalisierungsgenen zugrunde liegt, ist jedoch nicht klar. Ziel dieser Arbeit war es, den Mechanismus der Katecholamin-Biosynthese in PPGLs aufgrund von PVs in HRAS, einem mit Kinase-Signalwegen assoziierten Gen, zu untersuchen. Darüber hinaus wurden klinische Merkmale wie Katecholamin-assoziierte Anzeichen und Symptome, die prächirurgische Diagnose und die Entwicklung einer wiederkehrenden Erkrankung bei Patienten mit PPGL untersucht. Um den Katecholamin-Stoffwechsel bei PPGL zu untersuchen, wurden Katecholamine und PNMT-Enzymaktivitäten in 251 PPGL-Geweben gemessen. Anschließend wurden zwei Hotspot-Varianten von Hras, G13R und Q61R, durch CRISPR/Cas9-basiertes Prime Editing in eine Phäochromozytom-Zelllinie (PC12) der Ratte eingeführt. Katecholamine und nachgeschaltete HRAS-Faktoren, die die Epinephrin-Biosynthese regulieren, wurden in den Zellen mit/ohne Hras-PVs gemessen. Wir fanden heraus, dass PPGLs, die auf HRAS-PVs zurückzuführen sind, einen signifikant höheren Epinephrin-Gehalt und PNMT-Enzymaktivitäten aufweisen als solche, die auf PVs in Genen zurückzuführen sind, die mit Hypoxie-Signalwegen in Verbindung stehen. In Zelllinienversuchen steigerten PVs in Hras die Pnmt-Expression zusammen mit einer erhöhten Epinephrin-Synthese. Weitere Experimente zeigten, dass Hras-PVs die Pnmt-Expression durch Phosphorylierung von SP1 über den MAPK-Signalweg hochregulieren. Darüber hinaus verringerten Hras-PVs die Glukokortikoidrezeptorspiegel, wodurch die Empfindlichkeit gegenüber der gGukokortikoid-induzierten Expression von Pnmt reduziert wurde. Drei separate klinische Projekte wurden durchgeführt, um die mit Katecholaminen verbundenen klinischen Merkmale zu verstehen. Das erste Projekt untersuchte die Unterschiede in der klinischen Behandlung und die perioperativen Komplikationen bei Patienten mit Harnblasen-Paragangliom (UBPGL), die vor der Operation diagnostiziert oder fehldiagnostiziert wurden. In diesem Projekt wurde mehr als die Hälfte (53,6 %) der Patienten mit UBPGL vor der Operation nicht diagnostiziert. Wie erwartet wurden Patienten, die vor der Operation fehldiagnostiziert wurden, kaum mit einer alpha-adrenergen Blockade behandelt, und mehr dieser Patienten erlitten während der Operation eine Bluthochdruckkrise und perioperative Komplikationen als Patienten, die vor der Operation richtig diagnostiziert wurden. Eine weitere Analyse ergab, dass bei 34,5 % der Patienten mit Katecholamin-assoziierten Symptomen und/oder Bluthochdruck vor der Operation keine UBPGL diagnostiziert wurde. Darüber hinaus wurde Bluthochdruck als unabhängiger Faktor identifiziert, der mit der präoperativen Diagnose von UBPGL assoziiert ist. Das zweite Projekt untersuchte die Unterschiede im Auftreten von Katecholamin-assoziierten Zeichen und Symptomen bei Patienten mit und ohne metastasiertem PPGL (mPPGL). Wir konnten zeigen, dass das Auftreten von Katecholamin-assoziierten Anzeichen und Symptomen bei Patienten mit mPPGL mit der Produktion von Noradrenalin verbunden war, während es bei Patienten ohne mPPGL mit Epinephrin zusammenhing. Allerdings unterschieden sich die Anzeichen und Symptome bei Patienten mit metastasiertem PPGL nicht signifikant von denen mit nicht-metastasiertem PPGL. Das dritte Projekt untersuchte das Wiederauftreten der Krankheit bei Patienten mit sporadischem PPGL. Wir konnten zeigen, dass ein noradrenerger/dopaminerger Phänotyp des Primärtumors bei Patienten mit sporadischem PPGL ein unabhängiger Prädiktor für ein Wiederauftreten der Erkrankung ist. Darüber hinaus zeigten wir, dass bei 14,7 % dieser Patienten ein Rezidiv auftrat, bei einigen sogar noch 10 oder 15 Jahre nach der Resektion des Primärtumors. Diese Arbeit zeigte anhand von klinischen Tumorgewebedaten und in vitro gentechnisch hergestellten Zellmodellen, dass die Epinephrinbiosynthese bei PPGL vorwiegend durch den genetischen Hintergrund aufgrund von PVs in HRAS reguliert wird. Klinische Studien haben gezeigt, dass das Auftreten von Anzeichen und Symptomen, die prächirurgische Diagnose und das Wiederauftreten der Erkrankung mit dem Katecholaminstoffwechsel bei Patienten mit PPGL in Zusammenhang stehen. Daher muss der Katecholaminstoffwechsel bei der klinischen Behandlung von Patienten mit PPGL unbedingt berücksichtigt werden.:Content III Abbreviations: V List of figures and tables VII Zusammenfassung 1 Summary 3 1 Introduction and outline of the thesis 5 1.1 Pheochromocytomas and paragangliomas 5 1.2 Catecholamine metabolism in PPGLs 5 1.3 Pathogenic variants in the susceptibility genes of PPGLs 7 1.4 The association between genetic pathogenic variants and catecholamine metabolism in PPGLs 8 1.5 Catecholamine-associated clinical manifestations in patients with PPGLs 12 1.6 Catecholamine metabolite testing and diagnosis of PPGLs 12 1.7 Clinical treatment of patients with PPGLs 13 1.8 Follow-up for patients with PPGL 14 1.9 Outline of the thesis 15 2 Methods and results 17 2.1 Part 1: Regulation of epinephrine biosynthesis in HRAS-mutant paragangliomas 18 2.2 Part 2: Association of catecholamine metabolism and clinical management of patients with PPGL 67 2.2.1 Publication 1: 67 Differences in clinical presentation and management between pre- and postsurgical diagnoses of urinary bladder paraganglioma: is there clinical relevance? a systematic review 67 2.2.2 Publication 2: 74 Metastatic Pheochromocytoma and Paraganglioma: Signs and Symptoms Related to Catecholamine Secretion 74 2.2.3 Publication 3: 86 Recurrent disease in patients with sporadic pheochromocytoma and paraganglioma 86 3 General discussion 95 4 Conclusion 99 5 References 100 6 Acknowledgements 108 7 List of journal articles and invited presentations 109 8 Appendix 111 / Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors derived from chromaffin cells within the adrenal medulla (pheochromocytomas, PCCs) or extra-adrenal paraganglia (paragangliomas, PGLs). Patients with PPGL normally present signs and symptoms that are associated with catecholamine (dopamine, norepinephrine, epinephrine) biosynthesis, storage, and secretion. Catecholamine metabolism in PPGLs is influenced by the genetic background. Tumors resulting from pathogenic variants (PVs) in genes that lead to activation of hypoxia signaling pathways are unable to synthesize epinephrine, whereas those resulting from PVs in genes that activate kinase signaling are capable of epinephrine synthesis. This genetic-biochemical-clinical phenotype has been revealed in clinical research. However, the mechanism behind the regulation of catecholamine biosynthesis in tumors due to PVs in kinase signaling genes remains unclear. Thus, this thesis aimed to investigate the mechanism of catecholamine biosynthesis in PPGLs due to PVs in HRAS, a gene associated with kinase signaling pathways. In addition, clinical features such as catecholamine-associated signs and symptoms, a presurgical diagnosis, and the development of recurrent disease in patients with PPGL were studied. To investigate the catecholamine metabolism in PPGLs, catecholamines and PNMT enzyme activities of 251 PPGL tissues were measured. Subsequently, two hotspot variants of Hras, G13R and Q61R, were introduced into a rat pheochromocytoma cell line (PC12) using CRISPR/Cas9-based prime editing. The levels of catecholamines and downstream factors of HRAS that regulate epinephrine biosynthesis were measured in the cells with/without Hras PVs. We found that PPGLs resulting from HRAS PVs had significantly higher epinephrine content and PNMT enzyme activities compared to those resulting from PVs in genes associated with hypoxia signaling pathways. Furthermore, in our cell line experiments, PVs in Hras increased Pnmt expression, along with increased epinephrine synthesis. Moreover, further experiments indicated that Hras PVs upregulated Pnmt expression through phosphorylation of SP1 via the MAPK pathway. In addition, Hras PVs decreased glucocorticoid receptor levels, thereby reducing sensitivity to glucocorticoid-induced expression of Pnmt. Three separate clinical projects were performed to better understand the clinical features associated with catecholamines. The first project investigated the differences in clinical management and per-operative complications between patients with urinary bladder paraganglioma (UBPGLs) who were correctly diagnosed and those who were misdiagnosed before surgery. In this project, more than half (53.6%) of the patients with UBPGL were not diagnosed before surgery. As expected, patients who were misdiagnosed before surgery received limited treatment with alpha-adrenergic blockade, resulting in a higher incidence of hypertension crisis during surgery and perioperative complications compared to patients diagnosed before surgery. Further analysis indicated that 34.5% of these patients presenting with catecholamine-associated symptoms and/or hypertension were not diagnosed with UBPGL before surgery. In addition, we identified hypertension as an independent factor associated with pre-surgical diagnosis of UBPGLs. The second project analyzed differences in the presentation of catecholamine-associated signs and symptoms in patients with and without metastatic PPGL (mPPGL). We showed that the presentation of catecholamine-associated signs and symptoms was associated with the production of norepinephrine in patients with mPPGL, whereas in non-mPPGL patients, it was associated with epinephrine. However, the signs and symptoms in patients with metastatic PPGLs did not significantly differ from those in patients with non-metastatic PPGL. The third project analyzed recurrent disease in patients with sporadic PPGL. We showed that a noradrenergic/dopaminergic phenotype of primary tumors was an independent predictor of recurrent disease among patients with sporadic PPGL. In addition, we showed that 14.7% of these patients experienced recurrent disease, with some cases occurring even 10 or 15 years after the resection of their primary tumors. This thesis, through the use of clinical tumor tissue data and in vitro genetically engineered cell models, indicated that epinephrine biosynthesis was predominantly regulated by the genetic background in PPGLs with PVs in HRAS. Additionally, clinical studies showed that the presentation of signs and symptoms, a pre-surgical diagnosis, and the presence of recurrent disease were associated with catecholamine metabolism in patients with PPGL. It is therefore imperative to consider catecholamine metabolism in the clinical management of patients with PPGL.:Content III Abbreviations: V List of figures and tables VII Zusammenfassung 1 Summary 3 1 Introduction and outline of the thesis 5 1.1 Pheochromocytomas and paragangliomas 5 1.2 Catecholamine metabolism in PPGLs 5 1.3 Pathogenic variants in the susceptibility genes of PPGLs 7 1.4 The association between genetic pathogenic variants and catecholamine metabolism in PPGLs 8 1.5 Catecholamine-associated clinical manifestations in patients with PPGLs 12 1.6 Catecholamine metabolite testing and diagnosis of PPGLs 12 1.7 Clinical treatment of patients with PPGLs 13 1.8 Follow-up for patients with PPGL 14 1.9 Outline of the thesis 15 2 Methods and results 17 2.1 Part 1: Regulation of epinephrine biosynthesis in HRAS-mutant paragangliomas 18 2.2 Part 2: Association of catecholamine metabolism and clinical management of patients with PPGL 67 2.2.1 Publication 1: 67 Differences in clinical presentation and management between pre- and postsurgical diagnoses of urinary bladder paraganglioma: is there clinical relevance? a systematic review 67 2.2.2 Publication 2: 74 Metastatic Pheochromocytoma and Paraganglioma: Signs and Symptoms Related to Catecholamine Secretion 74 2.2.3 Publication 3: 86 Recurrent disease in patients with sporadic pheochromocytoma and paraganglioma 86 3 General discussion 95 4 Conclusion 99 5 References 100 6 Acknowledgements 108 7 List of journal articles and invited presentations 109 8 Appendix 111

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