Review on anti-cancer activity in wild plants of the Middle East.

Background: The Mediterranean basin is one of the richest biodiversity areas in the world, and the use of medicinal plants for treating cancer in this area has been documented for generations in different cultures. Objective: To present and discuss the findings related to medicinal plants with confirmed data on active compounds and/or clear mode of action. Methods: We undertook a structured search of bibliography of peer-reviewed research literature using key words and a focused review question. Papers with sufficient quality were reviewed, their findings presented and integrated into a coherent, state of the art document on wild plants of the Middle East with anti-cancer activity. Results: 121 papers were included in the review, among them 10 define herbal medicine, 3 describe the status of cancer worldwide, 18 discuss biodiversity, chemodiversity, ethnopharmacological survey and conservation of medicinal plants, 12 describe well known natural products from plants used to treat cancer and 78 papers describe specific compounds and mode of action in different wild plants from the middle east, traditionally used to treat cancer. Conclusions: Confirmed data on active compounds and/or clear mode of action exist for several wild plants traditionally used in herbal medicine to treat cancer. Yet, medicinal plants were mainly gathered from the wild, resulting in some of the commonly used herbs becoming endangered species. Also, in many cases, the activity and biochemical profile of plants harvested over different time spans and ecosystems may vary. Rational cultivation may ensure optimized yield with a uniform high quality of products.