Apoptosis as a biomarker in chemoprevention trials.

Monitoring apoptosis in histologic samples is becoming increasingly important as more effort is applied to the study of therapeutic modulators of cell death in tumors. The common methods used to monitor DNA fragmentation and cell morphology as markers of apoptosis have their own set of advantages and disadvantages. Growing knowledge of the signaling events that occur during cell death has established the caspase enzymes as the central executioner proteases of apoptosis. The results of caspase activity generate neo-epitopes that occur only during apoptosis. Directly monitoring caspase-mediated events as markers of apoptosis offers advantages over existing assay methods. Recently, several new marker antibodies have been developed that detect active caspase enzymes or the products they produce. The possibility of using these new marker antibodies for monitoring prostate chemoprevention trials is presented in this review.