Polo-like kinase 1 (PLK1), which helps orchestrate key events in the cell cycle, has been preclinically validated as an anticancer target, whereas it seems that the closely related kinases PLK2 and PLK3 might act as tumour suppressors. Strebhardt reviews recent insights into the biology of PLKs, with emphasis on their role in malignant transformation, and examines progress in the development of small-molecule PLK1 inhibitors as anticancer drugs.
