Anti-Cancer Plants Being Grown

Monday, July 24th 2000, 12:00 am
By: News On 6

WHITE PINE, Mich. (AP) — The high-intensity light bulbs and rows of plants make the scene look like an ordinary, garden-variety greenhouse.

But these tobacco plants are growing 200 feet below the earth's surface — in an abandoned copper mine converted into what is believed to be one of the first underground plant growth chambers in the United States.

In an environment where temperature, lighting and moisture are carefully regulated, a Canadian biotechnology company is cultivating genetically altered tobacco. Its seeds are being used to produce a protein that scientists hope to develop into medicine to fight bone marrow cancer, officials said in announcing the project Friday.

``We're embarking on a new era in which we will mass-produce biopharmaceuticals using plants to generate these proteins, instead of doing it synthetically in a laboratory,'' said Brent Zettl, president of Prairie Plant Systems Inc., of Saskatoon, Saskatchewan.

The Canadian national health agency, which engineers the tobacco plants, has signed a contract to have them grown in the White Pine underground chamber. The unique setting, with its elevated carbon dioxide level, speeds plant maturity.

``They grow so much faster here, it cuts the production time in half,'' said Dr. Anil Dudani, a Health Canada scientist taking part in studies with the proteins.

While using plants for medicinal purposes is nothing new, scientists are still learning to transfer human genetic material into plant cells. The plants are capable of turning the material into proteins, which are extracted from the seeds and made into drugs.

Plants are a cleaner and less expensive vehicle for protein production than conventional means such as fermentation in vats, Zettl said.

Somewhat ironically, given its reputation for endangering human health, tobacco is widely used in medical research because of its adaptability, he said.

``It's the white rat of plant genetics,'' Zettl said.

Prairie Plant Systems began growing plants in a copper and zinc mine in Manitoba nine years ago. When Copper Range Co. announced its plans to close of the White Pine mine in 1995, Zettl was invited to use a small section for a plant chamber.

After four years of negotiations and studies, Zettl's company formed a joint venture with local investors. Start-up costs have reached about $380,000.

Forty tobacco plants are now growing in the chamber. If they succeed, Health Canada will request 1,000, said Mark Pierpont, controller of SubTerra LLC, the joint venture.

Officials hope eventually to get beyond the trial stage and begin commercial production, enabling them to expand the growth chamber from its present 3,000 square feet to perhaps 500,000 square feet. Plants such as rice and flax, which have bigger seeds, might be used for commercial production of plants that could fight a variety of chronic diseases, Zettl said.

Another goal is to have laboratories on site, where seeds from the growth chamber could be processed into drugs instead of being sent elsewhere.

All that will depend on whether the growth chamber lives up to its early promise, Zettl said. The tobacco plants, the first of which began growing in early April, are already flowering and producing seeds, which shortly will be shipped to the Health Canada lab in Ottawa.

The chamber environment is a stark contrast with the rest of the dark, silent mine, where temperatures remain around a chilly 60 degrees. Inside, the plants flourish in 80-degree temperatures, with ideal amounts of water and artificial light and no pests or diseases.

The setting also prevents any genetically modified material from being blown or carried by insects to other locations, one of the concerns with biotechnology, said Bob Craig of the Michigan Department of Agriculture.

For Pete Rigoni, supervisor of Carp Lake Township, which includes the village of White Pine, the mine's new mission is a welcome — if unexpected — twist after its long history as a copper producer.

He hopes the venture signals new growth and jobs for the village, where about 700 people — mostly retirees — now live. Most young families left after the mine closed and cut 1,000 jobs; only about 110 students attend the school, down from more than 600 in the mine's heyday.

``We've been a one-industry community for a long time, with lots of peaks and pits ... always hinged on the price of copper,'' Rigoni said. ``Now we have a high-tech underground growth chamber. Now that's really unique.''