Antagonizing effect of triphenyltin chloride on cytosine-1-beta-D-arabinofuranoside potentiation of chromosome aberrations induced by mitomycin C.

We previously reported that the organotin triphenyltin chloride (TPTC), which has been widely used as an anti-fouling coating for fishing nets and ship bottoms, potentiated clastogen-induced chromosome aberrations during the G2 phase of the cell cycle. In this communication, CHO cells treated with mitomycin C (MMC) were post-treated with TPTC in the presence and absence of other agents--cytosine-1-beta-D-arabinofuranoside (araC), hydroxyurea, or caffeine--having a similar effect during the G2 phase of the cell cycle. The potentiating effect of araC was completely inhibited in the presence of TPTC at the concentration at which TPTC showed its potentiating effect, suggesting that potentiating effects of TPTC and araC are antagonistic. On the other hand, combined treatment with TPTC and caffeine or hydroxyurea showed a potentiating effect almost equal to the sum of the potentiating effects of each given separately.