- DNA-synthesizing enzymes in breast cancer (thymidine kinase, thymidylate synthase and thymidylate kinase): association with flow cytometric S-phase fraction and relative prognostic importance in node-negative premenopausal patients. Romain, S., Bendahl, P.O., Guirou, O., Malmström, P., Martin, P.M., Fernö, M. Int. J. Cancer (2001)