Cancer Drug Discovered in Sunflower Seed Protein

Australian scientists have demonstrated sunflower proteins and their processing machinery are commandeered to produce rogue protein rings in a discovery that could provide avenues to less expensive, plant-based drug manufacturing.

Dr. Joshua Mylne hopes his research has found another use for these plants through the manufacture of cheap therapeutic drugs. Dr. Joshua Mylne and Prof. David Craik, both from the University of Queensland's (UQ) Institute for Molecular Bioscience (Brisbane, Australia), unraveled the manner in which sunflower seeds assemble protein rings, one of which has previously demonstrated potential as a drug for cancer.

The study, published March 21, 2011, in the international journal Nature Chemical Biology, revealed that the machinery used to process and mature otherwise dull seed storage proteins is controlled by a protein ring, SFTI, for its own use. Dr. Mylne and Prof. Craik used the model plant Arabidopsis for their research, demonstrating that the sunflower protein-production system could be moved into another species and therefore SFTI could be manufactured in a range of plants.

Whereas this is of interest to researchers by providing an understanding of how new proteins can evolve and how proteins are matured, it has wider applications for drug production. SFTI can be used in its natural form to block breast cancer enzymes, and in a modified form to block enzymes associated with other types of cancer.

These proteins have not been widely used by drug designers despite their potential to fight cancer because of the expense of producing them using conventional, synthetic manufacturing methods.

"Although SFTI and related proteins show great promise as drug templates, the cost to manufacture them is a significant barrier to widespread use,” Dr. Mylne said. "This issue could be solved through plant manufacturing. Seeds are an attractive system for the production of pharmaceuticals, as they are cheap to grow and their contents are stable at room temperature, and sterile inside their coat. There are also established systems in place for their production, harvest, storage, and transportation, meaning they could be the ultimate low-cost drug delivery system.”

Related Links:
University of Queensland Institute for Molecular Bioscience