Correlation of results of agglutination assays with concanavalin A and carcinogenesis experiments on promoters of bladder cancer.

The promoting effects of various chemicals and dietary constituents on bladder carcinogenesis were examined by means of a short-term assay, in which maintenance of concanavalin A agglutination of isolated rat bladder cells caused by a subcarcinogenic dose of N-butyl-N-(4-hydroxybutyl)nitrosamine was used as an indicator. Twenty-seven chemicals were examined as possible promoters. Positive results in this assay were consistent with established promoting effects in the cases of sodium saccharin, saccharin, sodium L-ascorbate, sodium cyclamate, DL-tryptophan, butylated hydroxyanisole, butylated hydroxytoluene, L-thioproline and phenacetin. Allopurinol was the only established promoter that gave negative results in the agglutination assay. Thus, this method is useful for rapid evaluation of the specific promoting effect of a chemical on bladder carcinogenesis.