Could Plant Growing Near Mount Vernon Prevent Lung Cancer?

Source from:  By Mike Penprase News-Leader 06/21/2004

Alone, no; but studies show that mixed with 5 other herbs, it may be powerful. Starting with an unassuming plant that has a small spike of tiny blue flowers, researchers at the University of Missouri's Southwest Center are trying to determine whether a traditional Chinese herbal medicine can help prevent lung cancer. They and colleagues at the Missouri Botanical Garden in St. Louis hope ingredients from six plants used by the Chinese for hundreds of years — including selfheal, grown at the Southwest Center — will be shown to cut pre-cancerous cells. [img border=0 hspace="4" vspace="4" align="left" src=http://www.tobaccochina.com/english/picture/0620-Couldplant_1.jpg] But Andy Thomas, associate researcher and horticulturist at the center, and Botanical Garden curator James Miller caution the research is in its early stages and could take years to show results. Medical studies indicate that people taking the herbal medicine had a reduced risk of lung cancer of 40 to 50 percent. This has prompted an effort to grow the plants in the United States. Researchers here hope to determine how the mixture of ingredients from six plants works. "Whether it turns out to be any miracle cure or not, I don't know," Thomas said from his office at the center better known for providing advice to farmers. [img border=0 hspace="4" vspace="4" align="right" src=http://www.tobaccochina.com/english/picture/0620-Couldplant_3.jpg] Thomas has had previous experience in the emerging field of using plants in medicine. When he was employed by the Missouri Botanical Garden, Thomas went to the African nation of Cameroon to help study the potential of a plant said to have AIDS-fighting properties. More recently, he has been growing black cohosh, a flowering plant used by American Indians found to have properties that ease the discomfort of menopause, to determine whether it can be grown commercially by Missouri farmers. Cultivating black cohosh began with two plants and ended up with hundreds being grown over three years. The experiment concludes this fall when the plants are dug up and the roots processed. [img border=0 hspace="4" vspace="4" align="left" src=http://www.tobaccochina.com/english/picture/0620-Couldplant_4.jpg] Working with the Botanical Garden on what's known as Anti-Tumor B, or Anti-Cancer Health Preventive Health Agent (ACAPHA), will require even more effort than growing black cohosh, Thomas said. A $3,000 grant for initial horticultural work is financing a project involving two assistants and Thomas. While some of the plants in the mixture are common to the United States and Asia, others are found only in Asia. Prinella vulgaris, better known as selfheal, is relatively easy to find, especially in Ohio and North Carolina, where it's considered a weed. "I wouldn't mind, if I have time, to dash out there," Thomas said. Another plant native to Asia and the Pacific known as air potato, air yam or Chinese potato was introduced to the United States in 1905 and is considered a pest rivaling kudzu in Florida and other Southeast states, where its vines can grow 60 or 70 feet. Air potato already is known to contain useful compounds, including one used in birth-control pills. Finding Sophora tonkinensis could be more difficult. The plant that can resemble a tree or bush is found in Vietnam, and is known as Gapnep. "The Sophora, I don't think we'll be able to find it for a while," Thomas said. "Part of the grant is to find it and get it." There also are plants known as dragonwort, dittany root-bark and sow-thistle in the concoction. It might take up to a year to find seeds or other parts of plants that can be propagated, but Miller said he's confident that can be done. He heads the Missouri Botanical Garden's natural products research effort that includes cultivating plants that form ACAPHA at the garden's Shaw Nature Research Center in Gray Summit. In fact, Thomas said he should get a shipment of seeds within days. Having two sites growing the same plants will help determine how they react to different conditions and growing methods, Miller said. Determining whether the plants can be grown far from their native territories is important both in making widespread cultivation by farmers in Missouri and other states possible, and to protect native plants, he said. Part of the garden's conservation efforts in foreign countries involves trying to determine whether threatened plants have useful properties and might be grown by farmers rather than taken from the wild, he said. The threat isn't only from land-clearing, Miller said. "In many cases, long before the forests are cleared, local people have extracted the useful plant species to the point there are none left," he said. Another question that has to be answered is how the ingredients work in concert, Miller said. Although the breast cancer-fighting compound tamoxifen was found in yew tree bark, determining how compounds from six plants interact to prevent lung cancer is much more involved, he said. In part, that's because Western physicians aren't familiar with using medicines with many ingredients that interact with each other, Miller said. "It's difficult to know what role each of the six species play," he said. "It's even difficult to know if all the plants are needed. You get those kinds of activities in some of these herbal products you don't get in a single compound. We're really at the infancy of understanding that kind of pharmacology. Western pharmacology is very much based on understanding the chemical activity of one single compound." That's where the medical researchers play a role. Money Thomas received to grow plants and funding for work at the Missouri Botanical Garden comes from a National Institutes of Health grant originally awarded to the Washington University School of Medicine. The Botanical Garden is working with Dr. Ming You, a surgeon and researcher in preventive medicine on the staff of the school's Siteman Cancer Center. Although You was unavailable for comment, he has said in the past that research into traditional medicines is useful if those compounds' effects can show quantifiable medical effects. While You's research is in its early stages, researchers at the British Columbia Cancer Agency in Vancouver are in the midst of a clinical trial. One hundred people who have quit smoking or who still smoke are taking part. "The study is ongoing," agency spokeswoman Nicole Adams said. "We're looking at 2005 before it wraps up and several more months before the results are available," she said of the study that began in 2002. Miller said the Canadian researchers tell him ACAPHA looks promising. "They've got pretty good data, though," he said. "We have several grant applications pending that would provide significant support from the National Institutes of Health. But the preliminary data is very supportive that ACAPHA or Anti-Tumor B has some effect on preventing cancer." Thomas and two assistants are trying to find out whether the plants needed to produce ACAPHA can be grown in the United States. They've set up a collection of planting beds surrounded by fescue at the Mount Vernon research center. Instead of a white lab coat, Thomas wears blue jeans, a T-shirt and a straw hat while doing his work. A hoe for weeding is an important tool. Thomas' enthusiasm is shared by assistants Josh Norton and David Middleton, whose jobs involve weeding the plants and making sure they grow. A recent Southwest Missouri State University graduate, Middleton said he's excited to take part in an effort that could have widespread benefits. "It would be interesting to see how all this comes out," he said. But like any experienced gardener who has seen hope turn to resignation when a new plant doesn't survive, Thomas is cautious about what to expect. "It's research," he said. "It may go nowhere, but it could go somewhere." Enditem