Grant-in-Aid for international Scientific Research
|Allocation Type||Single-year Grants|
|Research Institution||Saitama Cancer Center|
FUJIKI Hirota Saitama Cancer Center, Res.Inst., Director, 研究所, 所長兼部長 (60124426)
IN Kyoung Li Ajou University School of Medicine, 所長
HAYASHI Shinichi Researcher, Saitama Cancer Center, Res.Inst., 研究所・生化学部, 主任研究員 (60144862)
SUEOKA Eisaburo Researcher, Saitama Cancer Center, Res.Inst., 研究所・血清ウイルス部, 研究員 (00270603)
SUGANUMA Masami Researcher, Saitama Cancer Center, Res.Inst., 研究所・血清ウイルス部, 主任研究員 (20196695)
LIM In Kyoung Professor, Ajou University, School of Medicine
|Project Period (FY)
Completed(Fiscal Year 1996)
|Budget Amount *help
¥1,100,000 (Direct Cost : ¥1,100,000)
Fiscal Year 1996 : ¥1,100,000 (Direct Cost : ¥1,100,000)
|Keywords||Hepato-carcinogenesis / Nodularin / Liver tumor promoter / Androgen receptor / Estrogen receptor / Early response gene / TNF-alpha / Endogenous tumor promoter / Gene expression|
Molecular studies on liver cancer development in humans
1. Expression of TNF-alpha gene and early response genes in primary cultured rat hepatocytes Nodularin, a potent liver tumor promoter strongly induces TNF-alpha mRNA and mRNAs of jun and fos gene families in rat liver two-stage carcinogenesis experiment. We studied whether rat hepatocytes induce expression of TNF-alpha gene and early response genes. Treatment of primary cultured rat hepatocytes with nodularin significantly induced enhancement TNF-alpha gene and stabilization of TNF-alpha mRNA.The effects were similar on the expression of early response genes.
2. Reduction of TGF-beta receptor expression in liver tumor promotion
TGF-beta receptor type 1 and 2 (TGF-beta RI and RII) was diminished in preneoplastic nodules induced by nodularin, indicating that reduced response to TGF-beta in preneoplastic cells in rat liver might be involved in hepatocarcinogenesis by nodularin.
3. Expression of TIS 21 gene in mouse skin two-stage carcino
TIS 21 gene is one of the genes induced in Swiss 3T3 fibroblasts by treatment with TPA.TIS 21 gene is thought to be one possible tumor suppressor gene. TIS 21 gene was expressed in normal mouse skin. An initiator, dimethylbenz (a) anthracene (DMBA) alone suppressed the expression, and a tumor promoter, okadaic acid, induced TIS 21 expression. However, the level of the expression was not much changed in papilloma and carcinoma of mouse skin.
To achieve successful collaborations with Korean scientists, we organized the Second Scientific Meeting on mechanisms of carcinogenesis and cancer chemoprevention in January this year in Korea, where 7 Japanese scientists and 9 Korean scientists presented new results. As a result of fruitful discussions at this meeting, a new collaboration on the study of TIS21, a putative tumor suppressor gene, has been started, between Professor Yamamoto's laboratory at the Institute of Medical Science, Tokyo University and Dr.Lim's laboratory at Ajou University. Less