Thèse de doctorat en Sciences de la vie
Sous la direction de Marie Juana Escribano.
Soutenue en 1986
à Paris 11 , en partenariat avec Université de Paris-Sud. Faculté des Sciences d'Orsay (Essonne) (autre partenaire) .
Pas de résumé disponible.
Differenciation proteins from pancreatic acini : their association with pancreatic development and carcinogenesis, isolation and caracterization
This work is a study of hamster foetal pancreatic proteins. These proteins were detected with an antiserum raised against foetal or neonatal pancreatic homogenates. They are highly specific of acinar cells. They are associated with gestational stages and pancreatic development. In a foetus a reaction is observed from the 9th day of gestation. The proteins were not found after the l0th day after delivery. The expression reaches a peak between the 14th day of gestation and the day of birth (16th day). A study of pancreatic chemical carcinogenesis showed a reexpression of these proteins at very early stage ; this reexpression persists throughout the neoplasic transformation. A good corelation between presence of the proteins and tumoral transformation was established by pancreas grafts into syngeneic individuals. Our results suggest that pancreatic adenocarcinoma might originate in acinar cells. Western blot results indicate a great heterogenity of the foetal extract, with relative molecular weights (Mr) ranging from 17 x 10-3 to 110 x 10-3. The homogenate includes two major proteins of 58 x 10-3 and 80 x 10-3, which were isolated by affinity chromatography on Concanavalin A combined to preparative e1 ectrophoresis. Some of the foeta1 proteins enter the circulation in over 80 % of tumor bearing hamsters long before a tumor can be detected. In conclusion, acinar cells contain specific proteins: differenciation proteins associated with an early stage of pancreas neoplasic transformation.