DIETARY PHYTOCHEMICALS IN CELL CYCLE ARREST AND APOPTOSIS- AN INSIGHT

Recently chemoprevention by the use of naturally occurring dietary substances is considered as a practical approach to reduce the ever-increasing incidence of cancer. While a number of natural foods, fruit and vegetables are recommended for prevention of cancer and other diseases, their active ingredients and their mechanism of action are not well understood. A number of dietary phytochemicals are under phase III clinical trial due to their potent therapeutic effect against cancer. Moreover most of the drugs being used in chemotherapy have been derived from plant products. With an advanced knowledge of molecular science and refinement in isolation and structure elucidation techniques, world is in a much better position to identify various anticancer herbs and develop therapeutic agents for cancer. However lack of success with targeted mono-t herapy and multi-drug resistance to existing chemotherapeutic agents has forced scientists to practice either combination therapy or use a number of agents working at different sites to get some synergistic effect. Since most of the cells do not show resistance to natural plant products; hence the use of natural plant products can be an alternative modality of treatment for multidrug resistant tumors. In this review article an attempt has been made to put some known phytochemicals of dietary origin that act at various stages of cell cycle and/or apoptotic pathway at a single platform, so that by understanding the synergistic, additive or antagonistic interactions of various constituents of anticancer herbs, the herbal regimens can be designed to fight cancer.