Grant-in-Aid for Overseas Scientific Survey.
|Section||Special Cancer Research|
|Research Institution||NAGOYA CITY UNIVERSITY|
ITO Nobuyuki Nagoya City University, 医学部, 教授 (00079956)
CHAWALIT Pai Khon Kaen大学, 医学部, 助教授
WITAYA Thama Mahidol大学, 医学部, 助教授
伊藤 誠 名古屋市立大学, 医学部, 助手 (90137117)
白井 智之 名古屋市立大学, 医学部, 助教授 (60080066)
PAIROJKUL Ch Khon Kaen大学, 医学部, 助教授
THAMAVIT Wit Mahidol大学, 医学部, 助教授
CHAWALIT PAI Khon Kean大学, 医学部, 助教授
WITAYA THAMA Mahidol大学, 医学部, 助教授
THAMAVIT Witaya Mahidol University
PAIROJKUL Chawalit Khon Kaen University
SHIRAI Tomoyuki Nagoya City University
ITO Makoto Nagoay City University
|Project Fiscal Year
1990 – 1992
Completed(Fiscal Year 1992)
|Budget Amount *help
¥15,000,000 (Direct Cost : ¥15,000,000)
Fiscal Year 1992 : ¥5,000,000 (Direct Cost : ¥5,000,000)
Fiscal Year 1991 : ¥6,000,000 (Direct Cost : ¥6,000,000)
Fiscal Year 1990 : ¥4,000,000 (Direct Cost : ¥4,000,000)
|Keywords||Opisthorchis viverri / Cholangiocellular carcinoma / Thailand / Liver cancer / タイ国 / 胆管細胞癌 / タイ肝吸虫 / 肝癌 / 発癌物質 / 胆管炎 / 抗タイ肝吸虫抗体 / プラジカンテル / 肝内胆管癌 / B型肝炎ウイルス / 肝吸虫|
The northeast area of Thailand where the liver fluke parasite Opisthorchis viverrini (OV) is endemic and economically disadvantaged people eat law fish harboring parasite matacercariae has a high incidence of cholangiocellular cancer. The present investigation was performed to clarify the histopathological characteristics of cholangiocellular carcinomas associated with OV infection, to determine natural carcinogen contamination in foodstuffs, to assess any association with hepatitis virus and to examine predictive value of anti-OV antibodies for early detection of cancer development.
(1) No obvious aflatoxin B1, B2, G1 and G2, sterigmatocystin, ochratoxin, dimethylnitrosamine, or diethylnitrosamine contamination was found by high pressure liquid chromatography or the mass fragment method in the Pla-ra fish sauce prepared in the northeast Thailand.
(2) No association of HVB infection with bile duct carcinoma development in northeastern Thailand was evident from HBs antigen analysis of 93
patients with cholangiocellular carcinomas.
(3) Anti-OV antibody was detected in all patients with cholecystitis and/or cholangiocellular carcinomas, higher titers suggesting a higher risk of cancer development.
(4) Proportions of different cholangiocellular tumor types in northeast Thailand were similar to those in Japanese cases except that the medullary type of poorly differentiated tubular adenocarcinoma was only found in Thai patients. Inflammatory reaction in the bile ducts and earlier development of tumors were apparent in association with parasites.
(5) Bile duct ligation enhanced the development of dimethylnitrosamine-initiated hamster cholangiocellular carcinomas, mimicking bile duct obstruction by heavy OV infestation and regenerative epithelial proliferation in man.
(6) Praziquantel, an anthelminthic agent was found to enhance diethylnitrosamine-initiated rat liver carcinogenesis. However, since the effective dose for promotion was extremely high, no adverse effect in man is expected.
In conclusion, prolonged inflammation and regenerative epithelial hyperplasia appear to play important roles in development of cholangiocellular carcinomas in northeast Thailand. Less