Abstract

Despite recent efforts in the development of anticancer drugs, malignant disorders have still remained one of the leading causes of death worldwide. The rapid ongoing increase in the number of new cancer cases predicted by WHO for the next few decades also demands implementation of more intensified chemopreventive and chemotherapeutic strategies. More than half of the chemotherapeutic drugs currently used in the clinical setting are of natural origin. It means that they are either directly derived from natural sources, or their structures are inspired by compounds isolated from the nature. At that plant extracts have proved to be an important biological material. This article presents a review about the origin, anticancer activities and action mechanisms of four plant-derived classes of chemotherapeutic drugs (vinca alkaloids, podophyllotoxins, taxanes and camptothecin analogues). Based on the huge diversity of chemical structures and biological activities of natural products, discovery of novel drug candidates originating from plants can be expected in the next few years. Both preclinical and clinical studies in this field worldwide are directed to expanding our current arsenal for fighting against cancer.