Tetraploidy-linked sensitization to CENP-E inhibition in human cells

Abstract

Tetraploidy caused by whole-genome duplication is a hallmark of cancer cells, and tetraploidy-selective cell growth suppression is a potential strategy for targeted cancer therapy. However, how tetraploid cells differ from normal diploids in their sensitivity to anti-proliferative treatments remains largely unknown. In this study, we found that tetraploid cells are significantly more susceptible to inhibitors of a mitotic kinesin CENP-E than diploids. CENP-E inhibitor preferentially diminished the tetraploid cell population in diploid-tetraploid co-culture at optimum conditions. Live imaging revealed that tetraploidy-linked increase in unsolvable polar chromosome misalignment caused substantially longer mitotic delay in tetraploids than in diploids upon moderate CENP-E inhibition. This time gap of mitotic arrest resulted in cohesion fatigue and subsequent cell death, specifically in tetraploids, leading to tetraploidy-selective cell growth suppression. In contrast, the microtubule-stabilizing compound paclitaxel caused tetraploidy-selective growth suppression through the aggravation of spindle multipolarization. We also found that CENP-E inhibitor had superior generality to paclitaxel in its tetraploidy selectivity across a broader spectrum of cell lines. Our results highlight the unique properties of CENP-E inhibitors in tetraploidy-selective suppression, giving us clues on the further development of tetraploidy-targeting interventions in cancer.