Protein kinase inhibitors--potential chemotherapeutic agents.

Protein kinase inhibitors, widely exploited for elucidation of the biological functions of kinases, have more recently come under active consideration as potential chemotherapeutic agents for tumour and other diseases. A brief overview is presented of diverse approaches to the design and development of selective protein kinase inhibitors, and related problems such as donor and acceptor specificities, stereochemical aspects, emerging relationships between protein, sugar and nucleoside kinases. In particular, and contrary to popular belief that ATP-competitive inhibitors cannot be selective because of the close homology of the ATP catalytic sites, numerous examples are presented of such inhibitors which are both potent and selective for a given kinase or class of kinases. Some of these are undergoing preclinical trials. Attention is also directed to the role of cellular and viral protein kinases in the life cycle of viruses, and the potential of these enzymes, especially those encoded by, and essential for replication of, a given virus as targets for antiviral chemotherapy.