Calmodulin: a potential target for cancer chemotherapeutic agents.

Calmodulin is a ubiquitous, calcium-binding protein that is responsible for many of the intracellular actions of calcium. Recent evidence suggests that calmodulin may regulate cellular proliferation and that its function may be altered in malignancy. The discovery that drugs such as phenothiazines antagonize the action of calmodulin led to the study of these antagonists against tumor cells. It is now appreciated that calmodulin antagonists are cytotoxic, can restore the sensitivity of resistant cells to drugs such as doxorubicin and vincristine, and can augment the cytotoxicity of bleomycin. This report addresses the possibility of developing new forms of chemotherapeutic agents that work by disrupting the function of this intriguing molecule.