Natural products form a significant portion of medicinal agents that are currently used for the management of cancer. All these natural products have unique structures along with diverse action mechanisms with the capacity to interact with different therapeutic targets of several complex disorders. Although plants contribute as a major source of natural products with anti-cancer potential, the marine environment and microbes have also bestowed some substantial chemotherapeutic agents. A few examples of anti-cancer agents of natural origin include vincristine, vinblastine, paclitaxel, camptothecin and topotecan obtained from plants, bryostatins, sarcodictyin and cytarabine from marine organisms and bleomycin and doxorubicin from micro-organisms (dactinomycin, bleomycin and doxorubicin). The incredible diversity in the chemical structures and biological properties of compounds obtained from million species of plants, marine organisms and microorganisms present in nature has commenced a new era of potential therapeutic anti-cancer agents.

天然产物构成目前用于癌症治疗的大部分药物。所有这些天然产物具有独特的结构以及多种作用机制，能够与几种复杂疾病的不同治疗靶点相互作用。尽管植物是具有抗癌潜力的天然产物的主要来源，但海洋环境和微生物也赋予了一些重要的化学治疗剂。天然来源的抗癌药的一些例子包括从植物中获得的长春新碱，长春碱，紫杉醇，喜树碱和喜树碱，海洋生物中的抑菌素，降钙素和阿糖胞苷以及微生物（放线菌素，阿霉素和阿霉素）中的博来霉素和阿霉素。