Natural products in cancer therapy and Prevention

Cancer is a chronic immune and/or metabolic associated disorder which involves abnormal growth of cancer cells by destroying the surrounding healthy cells and ultimately metastasizes to other parts of the body. Cancer induction, growth and progression are therefore multi-step events. One of the oldest and most effective strategies for developing new chemotherapeutics is the isolation and evaluation of chemicals of natural origin which interfere with these stages of cancer, thus blocking malignancy. Many of the clinically active drugs that are presently used in cancer therapy are either natural products or are based on natural products. It is also apparent that materials from natural sources are excellent probes (indicators) for cellular targets that, when modulated, may have a deleterious effect upon the survival or proliferation of tumor cells.