Plants are endowed with biological catalysts (enzymes) that make natural drugs used to treat various human illnesses. Among these, the Chinese happy tree (Camptotheca acuminata) produces the anticancer drug camptothecin. Although camptothecin is readily convertible to the more potent drugs topotecan (Hycamtin) and irinotecan (Camptosar), this requires chemical synthesis steps which rely on toxic chemicals and petroleum-based resources.
Our research program aims at developing multidisciplinary approaches to discover and modify happy tree’s enzymes that facilitate the production topotecan, irinotecan and new camptothecin-derived analogues. We aim to rapidly generate 25-50 camptothecin-derived analogues by biotechnological means and test these compounds using in vitro and cellular assays to assess potential anti-cancer activity.
Our biosynthetic approach will allow us to explore the untapped medicinal potentials of a whole host of novel camptothecin-related chemicals in addition to topotecan and irinotecan. Long-term efforts, also ongoing in our laboratory, will focus on synthetic biology approaches to scale up production of compounds that show promising bioactivity.