The Preliminary Report of Rapid Production of Pancreas Cancer and Cholangiocarcinoma by Cyclic Injection of Carcinogens in Syrian Hamster initiated with N-nitrosobis(2-oxopropyl)amine

Ryu, Ki Sun; Jung, Seung Kyu; Kim, Wook Hwan; Wang, Hee Jung; Jin, Yoon Mi; Kim, Myung Wook

Abstract

BACKGROUND/AIMS: It is well known that N-nitrosobis(2-oxopropyl)amine(BOP)-induced pancreas cancer and cholangiocarcinoma in Syrian hamster is similar to that of humans in morphological, biological and immunological aspects. The cyclic administration of BOP and ethionine, choline-deficient diet and methionine is known to rapidly induce the ductal type of carcinoma in pancreas and bile duct. Authors studied whether the rapid production of this cancer can occur in Syrian hamster and what its features are.
METHODS
Sixteen Syrian hamsters aged 6-7 weeks and weighing 100 gm were used. All hamsters received 70 mg/kg body weight of BOP followed by three cycles of dl-ethionine, choline-deficient diet, l-methionine and 20mg/kg BOP. Hamsters were killed 9, 10 and 11 weeks after the beginning of the experiment and their gross and histologic features were observed.
RESULTS
Nine cases, killed withan 10weeks after the begining of experiment, showed no development of cancer. Of seven Syrian hamsters, killed more than 10weeks after the begining of experiment, the incidences of BOP-induced cancer included one case(14.3%) of pancreas cancer and five cholangiocarcinomas( 71.4%). The morphological change of pancreas carcinogenesis was shown at first in cell mitosis and atypia(6 weeks) and then in atypical ductal hyperplasia(9 weeks) and carcinoma in situ(10 weeks). The change in cholangiocarcinoma, first progressed with ductular proliferation and surrounding fibrosis(6 weeks) followed by focal cholangiocarcinoma(10 weeks) and multiple invasive cholangiocarcinomas( 11 weeks).
CONCLUSION
Pancreas cancer and intrahepatic cholangiocarcinomas can be induced rapidly within 10 weeks by cyclic injections of carcinogens in Syrian hamsters initiated with Nnitrosobis( 2-oxopropyl)amine and the morphologic changes can be observed.