This comprehensive volume explores the latest research on the mechanisms of resistance in cancer cells to CTL-mediated immunotherapy. Chapter topics discuss cell-mediated immunity as the result of cytotoxic T-lymphocytes (CTL) directed specifically against cancer cells. In addition, the volume reviews how CTL mediate the cytotoxic activity, in large part, by the indication of apoptosis; hence, tumor cells develop anti-apoptotic mechanisms and thereby, resist CTL-induced apoptosis. In order for CTL-mediated antitumor immunotherapy to be effective, it is essential that agents directed against the resistant tumor cells sensitized cancer cells for CTL-mediated apoptosis. Examples of such agents discussed in the volume include are HDAC inhibitors, proteasome inhibitors, Bcl-2 family inhibitors, PARP, antibodies, and more.