ATLA::Alternatives to Laboratory Animals

Volume 30, Number 1

Use of a cell transformation assay with established cell fines, and a metabolic cooperation assay with V79 cells for the detection of tumour promoters: a review.

Ayako Sakai1, Yumiko Iwase2,3, Yoshiyuki Nakamura4, Kiyoshi Sasaki5, Noriho Tanaka5, and Makoto Umeda5

1National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-850 1, Japan; 2Toxicology Laboratory, Mitsubishi Pharma Corporation, 100-5 Yana, Kisarazu City 292-081Z Japan; 3Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670, Japan; 4School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada, Shizuoka City 42280OZ Japan; 5Hatano Research Institute, Food and Drug Safety Centre, 729-5 Ochiai, Hadano City 2578523, Japan

SUMMARY

Extensive studies on the safety evaluation of chemicals have indicated that a considerable number of non-genotoxic chemicals are carcinogenic. Tumour promoters are likely to be among these nongenotoxic carcinogens, and their detection is considered to be an important approach to the prevention of cancer. In this review, the results are summarised for in vitro transformation assays involving established cell lines, and for an assay for inhibition of gap junctional intercellular communication for the detection of tumour promoters, which involves V79 cells. Although the number of chemicals examined is still too small to permit a full evaluation of the correlation between in vitro cell transformation and in vivo carcinogenicity, it is clear that the sensitivity of the focus formation assay is very high. In the case of the metabolic cooperation assay, the sensitivity appears to be rather poor, but the assay can be considered to be useful because of its simple procedure and its considerable database. These in vitro assays for tumour promoters are recommended as useful tools for the detection of nongenotoxic carcinogens.

Keywords: tumour promoters, transformation assays, established cell lines, metabolic cooperation assay, V79 cells