Inhibitors of cell cycle checkpoints and DNA replication cause different responses in normal versus malignant urothelial cells.

S-phase checkpoints are triggered in tumor cells in response to DNA replication stress caused by the tumor microenvironment or oncogenes. A recent report from our laboratory showed that tumor cells and more normal epithelial cells have a very different response to replication stress. In this Author's View, the implications of this finding are discussed.