Mutagenic activity of furylfuramide on cultured mouse cells.

Effects of furylfuramide (FF) on cultured FM3A cells a C3H mouse mammary carcinoma cell line, were examined. FF inhibited the growth at 10(-4.5) M, and provoked enlargement of cellular, nuclear and nucleolar size, cytoplasmic vacuolation and granular aggregation of chromatin. Chromosome preparation demonstrated severe aberrations in nearly 90% of mitotic plates after 24 and 28 hour treatment. The changes included gaps, breaks, exchanges and fragmentations, but were at chromatid level. Time course study of the incorporation of radioactive precursors showed the gradual but remarkable inhibition of 3H-thymidine uptake whereas 3H-uridine and 3H-leucine uptakes were fairly maintained. Thus, it is suggested that FF induced the block of G1 phase and the delay of S and/or G2 phase. According to the results of alkaline sucrose gradient analysis of cell DNA, breakage of the treated cell DNA was induced and the induced breakage was recovered after the incubation without FF. The capacity to induce 8-azaguanine-resistant mutant cells by FF was shown remarkably high.