• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • 1
  • 1
  • Tagged with
  • 3
  • 3
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 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.
1

La mutation K-RAS détectée dans la marge de résection veineuse d'une pièce de duodénopancréatectomie céphalique définit la notion de "marge génique" et peut modifier la technique chirurgicale

Turrini, Olivier 03 June 2013 (has links)
La technique d'une DPC pour adénocarcinome a évolué ces dernières années tant au niveau sécurité qu'au niveau carcinologique mais cela n'a pas suffit à faire progresser la survie. On peut se demander si la modification de la technique chirurgicale pourrait avoir un impact significatif sur la survie.A) Nous avons recherché, sur 23 pièces de DPC encrées, la présence de la mutation K-ras au niveau de la marge veineuse affirmée R0 en analyse histologique : 13 spécimens (groupe kras+) exprimaient une mutation K-ras au sein de la marge veineuse versus 10 spécimens (groupe kras-) ne l'exprimant pas. Les tumeurs des 2 groupes étaient comparables (taille, envahissement ganglionnaire, engainement périnerveux…). La survie globale à 1 an et 3 ans des groupes kras- versus kras+ étaient de 80% versus 84,6% et 16,7% versus 0% (p=0,03), respectivement. Les médianes de survie des groupes kras- versus kras+ étaient de 24 mois versus 16 mois (p=0,04), respectivement.B) Nous avons comparé, après appariement, 19 patients ayant eu une DPC avec résection « par excès » de la veine porte (groupe VP) avec 19 patients ayant eu une DPC sans résection de la veine porte (groupe contrôle). Les survies médianes et à 3 ans du groupe VP versus groupe contrôle étaient 42 mois versus 22 mois (p=0,04) et 60% versus 31% (p=0,03), respectivement.En conclusion, notre travail a montré qu'au-delà de la marge déterminée par le chirurgien pendant la chirurgie, de celle de l'anatomopathologiste déterminée par l'analyse microscopique, il existait une marge génique. La résection systématique de la veine porte semblait bénéfique car elle permettait sans doute de passer au-delà de cette marge génique. / Pancreticoduodenectomy (PD) for adenocarcinoma was safer during the last decades but did not improve survival. We sought to determine if technical changes during PD could improve survival.A) In a first study, we determine the presence of K-ras mutation in the venous margin of 23 PD's specimens. Thirteen specimens had K-ras mutation (kras+ group) and 10 specimens did not (kras- group). Except K-ras mutation status, tumors of the 2 groups were not different when comparing major histological findings (margin status, lymph node invasion, perineural invasion…). Overall 1- and 3-years survival of patients of kras- group versus kras+ group were 80% versus 84,6% and 16,7% versus 0% (p=0,03), respectively. Median survival of patients of kras- group versus kras+ group were 24 months versus 16 months (p=0,04), respectively.B) In a second study, we compared 19 patients with “excessive” portal vein resection during PD (PV group) with 19 matched patients who underwent PD without venous resection (control group). Median survival of patients of PV group versus control group were 42 months versus 22 months (p=0,04), respectively.In conclusion, we showed that the « genic margin » concept was consistent. Systematic portal vein resection could avoid positive genic margin and might be benefic for patient who underwent PD for resecable adenocarcinoma.
2

Entwicklung von neuen Behandlungskonzepten zur Therapie des Pankreaskarzinoms

Oettle, Helmut 16 April 2002 (has links)
Jährlich erkranken in Deutschland über 11.000 Patienten an Pankreaskarzinomen. Für die ganz überwiegende Mehrzahl dieser Patienten ist die Diagnosestellung gleichbedeutend mit einem Todesurteil innerhalb von wenigen Wochen, hauptsächlich bedingt durch das meist fortgeschrittene Krankheitsstadium bei Diagnosestellung sowie die relative Therapieresistenz des Tumors. Die vorliegende Arbeit faßt wissenschaftliche Untersuchungen zusammen, die in den zurückliegenden vier Jahren in Berlin zu dieser Thematik durchgeführt wurden. Stadienadaptiert wurden Behandlungskonzepte und klinische Studien entwickelt und durchgeführt, die von der adjuvanten Chemotherapie über ein Radiochemo-therapiekonzept bei lokal fortgeschrittenen Stadien hin zur Entwicklung einer neuen Zytostatika-Kombinationstherapie für die Behandlung metastasierter Pankreastumoren im Rahmen einer multinationalen Phase III Studie geführt haben. Neben diesen Schemata konnte auch eine wirksame Zweitlinientherapie geprüft werden. An Tumormaterial konnte gezeigt werden, daß sich keine Her2/neu-Überexpressionen bei Pankreastumoren nachweisen lassen, die therapeutisch nutzbar wären. Bei ca. 80 % aller Pankreaskarzinome lassen sich Mutationen des K-ras-Onkogens nachweisen. In Kooperation mit einer anderen Arbeitsgruppe wurde ein Verfahren entwickelt, mit dem sich qualitativ und semiquantitiativ schnell und zuverlässig ras-Mutationen nachweisen lassen. Diese klinischen Studienergebnisse geben Grund zur Hoffnung, die Prognose von Patienten mit Pankreaskarzinomen in den nächsten Jahren durch die hier vorgestellten Konzepte zu verbessern. Fortschritte im Verständnis der molekularen Karzinogenese, in Diagnostik und Therapie lassen in naher Zukunft Ergebnisse erwarten, die zumindest denen bei anderen soliden Tumoren nahekommen. Daher ist der vereinzelt noch verbreitete therapeutische Nihilismus bei der Behandlung des Pankreaskarzinoms als nicht länger gerechtfertigt und akzeptabel anzusehen. / In Germany, more than 11,000 patients are diagnosed with pancreatic cancer each year. For the vast majority, this means a death verdict within a few weeks, primarily due to the advanced stage of the disease at diagnosis and the relative chemoresistance of the tumor. This thesis summarizes the scientific work regarding pancreatic cancer that has been done within the last four years. Several clinical treatment concepts and studies were developed and conducted that covered the different stages of the disease, including adjuvant therapy, radiochemotherapy for locally advanced disease and a multinational phase III study for the patients with metastatic disease. In addition, an effective second line regimen was developed. Using tumor material, we found no overexpression of Her2/neu which would have been a therapeutically usable target. Mutations of the K-ras oncogene can be found in approximately 80% of patients with pancreas carcinoma. A method for a rapid and reliable qualitative and semiquantitative determination detection of ras mutations was developed in cooperation with another research group. The clinical results give rise to the hope that the prognosis of patients with pancreatic carcinoma can be improved during the next years using the concepts outlined above. Recent improvements in our understanding of the molecular carcinognesis together with advances in diagnostics and therapy give rise to the expectation that clinical results will be achievable that will be at least as good as those for other solid tumors. Therefore, nihilism regarding the treatment of pancreatic cancer that still can be found is no longer justifiable or acceptable.
3

The effect of RAN inhibition on human colorectal cancer cells (CRC)

Elrewey, Hussein A.S. January 2020 (has links)
Colorectal cancer (CRC) is the third most widespread and fourth most fatal malignancy disease. The CRC from a primary site can spread to other tissues, forming secondary tumours. CRC can metastasise to the liver through the effect of K-Ras and Pten mutation (Mt.) (Abbas et al. 2020). This study aimed to assess the hypothesis that the Ran inhibitor mebendazole MBZ reduces cell invasion and metastasis of CRC. I have investigated MBZ effect on the CRC isogenic human cell lines with specific mutations (HCT-116 K-Ras, DLD-1 K-Ras and Pten deletion and wild type HCT-116 and DKO-3. I used qRT-PCR and western blotting to identify expression levels of various genes and signalling molecules after treatment with 0.5 mM MBZ. In addition, several assays were performed to investigate MBZ effect on biological properties of the cells such as proliferation, migration, invasion, and colony formation. MBZ downregulated Ran and induced apoptosis through inhibition of Bcl-2 expression as well as inducing caspase -3, -7, -9 and PARP cleavage. Moreover, MBZ showed an effect on immune response by down regulating C5a, IL-1ß and IL-1α analysed at mRNA level. When treated with MBZ, the migration, invasion and colony formation abilities of HCT-116 K-Ras Mt., DLD-1 K-Ras Mt. and HCT-116 Pten-/- were significantly reduced compared to a control treated cell line. This was also the case with wild type cell lines such as HCT-116 and DKO-3. Furthermore, signalling molecules such as p- Erk 1/2 and p- Akt were upregulated after MBZ treatment and exert inhibition on Akt 1/2/3 and VEGFR1/2 mRNA levels. In conclusion; MBZ which is a Ran inhibitor, has significantly reduced proliferation, colony formation, and migration in colorectal cell lines with K-Ras and Pten gene deletion compared to wild type cells in a dose-dependent manner. This work paves the way to clinical validation of MBZ as a combination therapy for reducing the invasion of CRC cells.

Page generated in 0.1031 seconds