TY - JOUR
AU - Woutersen, R.A.
AB - Using immunohistochemistry, Northern blotting and a semi-quantitative PCRtechnique, epidermal growth factor (EGF), transforming growth factor-α(TGF-α) and epidermal growth factor receptor (EGFR) expression werestudied in the pancreas of N-nitrosobis(2-oxopropyl)-amine(BOP)-treated hamsters. After initiation pancreatic carcinogenesis was modulatedby a high fat diet or by injections with the cholecystokinin analogue caerulein.Autopsies were performed 6 and 12 months after the last injection with BOP.Immunohistochemistry revealed a weak expression of TGF-α innormal acinarcells and a stronger expression in ductular and centro-acinar cells.Over-expression of TGFα was observed in advanced putative preneoplasticlesions (classified as borderline lesions) and in ductular adenocarcinomas. EGFRimmunoreactivity was present only in ductular adenocarcinomas. EGF peptideexpression was observed both in acinar and ductular normal and tumorous cellsand the level of expression did not change significantly during carcinogenesis.Moreover, the post-initiation treatments did not cause differences in EGF,TGFα or EGFR peptide or mRNA levels, except for a significantly lowerexpression of TGF-α mRNA in hamsters fed a high fat diet when comparedwith those fed a low fat diet. TGF-α mRNA levels increased, whereas EGFmRNA levels decreased significantly in total pancreatic homogenates ofBOP-treated hamsters in comparison with untreated controls. Also, in ductularadenocarcinomas TGF-α and EGFR (butnot EGF) mRNA levels weresignificantly higher than in normal pancreatic homogenates. In pancreatichomogenates obtained 6months after the last BOP injection, these differenceswere less pronounced in comparison with those obtained after 12 months. Thepresent results indicate that TGF-α (but not EGF) might act in aparacrine or autocrine manner in pancreatic tumours in BOP-treated hamsters viasimultaneously expressed EGFR. However, TGFα, EGF and EGFR do not seem tobeinvolved in the modulating effects of a high fat diet or caerulein treatmenton pancreatic carcinogenesis in BOP-treated hamsters.
TI - Overexpression of transforming growth factor-α and epidermal growth factor receptor, but not epidermal growth factor, in exocrine ...
JO - Carcinogenesis
DO - 10.1093/carcin/17.4.779
DA - 1996-04-01
UR - https://www.deepdyve.com/lp/oxford-university-press/overexpression-of-transforming-growth-factor-and-epidermal-growth-onNIuJmqeK
SP - 779
EP - 785
VL - 17
IS - 4
DP - DeepDyve
ER -