Antibody-directed, effector cell-mediated tumor destruction

Effective cancer treatment requires the irreversible cessation of growth, o r destruction of cancer cells in vivo. Ideally, this antitumor effect shoul d be directed selectively against the cancer and cause little or no injury to normal tissues. Antitumor specificity (i.e., selective action against tu mor cells but not normal cells) can be provided by the surgeon's scalpel, b y the radiotherapist's treatment ports, and by the metabolic targets of cer tain cytotoxic drugs. The selectivity potentially provided by immunotherapy involves immune-mediated recognition of molecules (antigens) specifically or selectively expressed by tumor cells. This immune recognition of tumor a ntigens may be through cell-mediated recognition or through antibody-mediat ed recognition. The technology for creating monoclonal antibodies (mAbs) ha s allowed the development of many distinct purified reagents that recognize molecules selectively expressed on the surface of human cancer cells. This article summarizes how these mAbs can induce immune cells to destroy cance r cells in preclinical models and describes how these mechanisms are being tested as clinical cancer treatments.