Effects of resveratrol on topoisomerase II-α activity: induction of micronuclei and inhibition of chromosome segregation in CHO-K1 cells.

In recent years, a great interest has emerged in resveratrol (RSV) activity in the prevention of various pathologies including cancer. We recently showed that RSV is able to interfere with topoisomerase II-α (TOPO2) activity in cancer cells, thus inducing a delay in S-phase progression with concomitant phosphorylation of the histone H2AX. TOPO2 is mainly active in proliferating cells and is involved in the resolution of supercoiled DNA and chromosome segregation during mitosis. Here, we studied the effects of RSV in CHO-K1 cells concerning to chromosome damage and segregation as a consequence of TOPO2 inhibition. We show an increase in micronuclei and in polyploid and endoreduplicated cells due to incorrect chromosome segregation. Furthermore, since incomplete segregation can also affect the normal distribution of mitotic figures, we checked mitosis progression showing an increase in metaphase in relation to ana-telophase after RSV treatment. On the whole, our data show that RSV affects chromosome stability and segregation in proliferating cells, probably interfering with TOPO2 activity.