PLK1 and cancer: Since antimitotics, including those that target PLK1, rely on apoptosis to kill cancer cells and given the aforementioned two competitive networks that determine whether mitosis-arrested cells will die or undergo slippage, here, we investigated whether the inhibition of the anti-apoptotic BCL-2 family members can enhance cell death during mitotic arrest caused by a PLK1 inhibitor and, thus, identify a relevant strategy to improve the efficacy of PLK1 targeting, when it is combined with targeted apoptosis potentiators.