ETIOLOGY PROGRAM AREA

SUMMARY OF ACTIVITIES

The year April 1, 1987 to March 31, 1988 is the fourth year of the third 5-year program of the U.S.-Japan Cooperative Cancer Research Program. The aim of the Etiology Program Area is to clarify the causes of human cancers and to determine the mechanisms of carcinogenesis. It has been envisaged that cancer prevention may be achieved eventually through progress in the science of cancer etiology.
Four seminars were held during this period, all in the United States. The first seminar, “Development of New Medium-Term Bioassay for Carcinogens,” focused on development of new medium-term bioassays from both nations, and re-evaluation of a few selected older medium-term bioassay systems in light of recent experimental findings. It was felt that these bioassays might be useful in detecting carcinogens and tumor promoters, some of which may be presumed carcinogens, in a relatively shorter period of time (weeks to months) than for the standard rodent 2-year carcinogen bioassay, thus saving time and money. The second seminar, “Cancer Cell Membranes: Aberrant Glycosylation and Other Critical Molecular Events,” focused on aberrant glycosylation and other molecular changes expressed at the surface of cancer cells and defined by monoclonal antibodies. The third seminar, “Biology of Oncogenes,” focused on new information being developed in the field of oncogenes, growth factors/growth factor receptors and cancer. The fourth seminar, “Glutathione S-Transferases and Carcinogenesis,” focused on a discussion of the properties, regulation, genetic expression, and role of glutathione S-transferases and related functions in carcinogenesis drug resistance, and normal tissue expression.
Four scientists from Japan and one scientist from the United States participated in exchange programs in etiology research, which has as its mission to provide a fundamental basis for understanding cancer causation that, in turn, would help in identifying effective means for preventing or modulating this process.
During this reporting period, the following compounds were shipped from the United States to Japan:
5 mg of benzo(a)pyrene-trans-7,8-dihydrodiol-9,10-epoxide(anti),
5 mg of benzo(a)pyrene-trans-7,8-dihydrodiol-9,10-epoxide(syn),
5 mg of benzo(a)pyrene-4,5-dihydroepoxide,
50 mg each of fecapentaene-12 and fecapentaene-14, and
5 gm of nitrilotriacetic acid trisodium salt, monohydrate.
Also, the following compounds were shipped to the United States from Japan:
1.80 g of 2-amin0-3,4,8-trimethylimidazo (4,5-f) quinoxalin
1.91 g of 2-amin0-3,8-dimethylimidazo (4,5-f) quinoxalin