Published by Communications and Public Affairs 519 824-4120, Ext. 56982 or 53338

News Release

December 19, 2005

U of G Prof Aims to Cut Cost of Cancer Drug

A University of Guelph researcher is looking to Canada’s hardwood forests as a potential source of a critical – and expensive – component of a cancer-fighting drug.

Prof. Glenn Fox of the Department of Agricultural Economics and Business is working to determine the economic, environmental, commercial and social sustainability of perennially harvesting Canada yew trees because they're an important source of paclitaxel, a drug that has been effective in treating several types of cancer by stopping or slowing cancer cell growth. If Canada yew can be grown in large enough quantities and an effective harvest process is created, the drug’s price could fall dramatically, he said.

Paclitaxel – sold commercially as Taxol -- is extracted from the yew’s leaves and bark and is an especially important tool in the fight against breast cancer, a disease that will strike more than 20,000 Canadian women this year alone. The supply of paclitaxel is currently limited and the drug can cost thousands of dollars to treat a single patient.

The Ontario Woodlot Association (OWA) sees potential for farmers and other landowners to get involved in yew farming. It’s happening elsewhere – the OWA says that in 2003, taxane products (those that inhibit cell growth, such as paclitaxel) registered $4.2 billion US in sales worldwide, and the demand grows.

Fox is concerned with maintaining the sustainability and life of the tree. If not properly managed, an increased interest in its harvest could possibly lead to its demise. Before scientists knew the yew tree produced paclitaxel, it was basically ignored, making the number of available yew trees that can easily be harvested quite sparse, said Fox. It’s now a controlled species and it's extraction requires the tree to be pruned, which is a key challenge because it’s not known how much pruning the plant can take and survive.

The OWA recommends pruning three-years worth of growth; any more, and yew trees may die. As well, to maximize the taxane yield, harvest time is crucial. Taxane yield will generally be higher in dormant times of the year; late August to early April is the recommended harvesting time. Winter harvest is possible, but experts recommend harvest when the tree is dormant.

These are all management matters that would impact on a Canadian yew industry, said Fox.

Contact:
Prof. Glenn Fox
Department of Agricultural Economics and Business
(519) 824-4120, Ext. 52768
gfox@uoguelph.ca