January 11, 2005
Promising research from SIUC Ginseng root may help slow growth of cancer cells
CARBONDALE, Ill. — It can slow the growth of breast tumors, even those resistant to most drugs, and improve the action of commonly used chemotherapies, all with no side effects of its own.
It's an aphrodisiac, too.
"Ginseng root is a 'drugstore' with 20 to 30 different compounds — I've never worked with anything that complex," said Laura L. Murphy, a scientist in Southern Illinois University Carbondale's School of Medicine who has studied ginseng's effects since the early '90s.
Ginseng, an herb whose botanical name, panax, comes from the Greek "panacea," or cure-all, has a long history in Asian medicine as the drug of choice. Traditional healers have used it to treat everything from fatigue to high blood pressure to lack of sexual desire. In fact, it was ginseng's reputation as a sexual tonic that first got Murphy's attention.
Murphy specializes in the glands and hormones that affect, among other things, reproduction. Using lab rats, she and some of her students had already debunked the notion that marijuana has an aphrodisiac effect ("The higher the dose, the more difficulty male rats had having sex," she said). Taking a hard look at claims that ginseng boosted sexual prowess seemed a logical next step.
When her students fed ground-up American ginseng root to the rats, they all got a surprise.
"It had a tremendous effect on libido," she said. "I'd never seen a drug have that kind of effect before — it was amazing."
Intrigued, Murphy began looking for modern-day accounts of other studies done with this herb. She found Asian researchers doing most of the work, focusing mainly on ginseng's effectiveness in treating some kinds of cancer.
"But breast cancer and prostate cancer — two of the most common cancers that aging men and women get — had just fallen through the cracks," she said.
As an endocrinologist, Murphy had access to a supply of human breast cancer cells grown for researchers. When she and her students began treating some of these cells with a ginseng extract, they found that the higher the "dose" of ginseng, the more slowly the cancer cells grew. In fact, with a high enough dose, they could actually stop the cells from growing at all.
"It was consistent and repetitive — a very clean result," she said.
At this point, the U.S. Department of Defense, which has an interest in novel therapies and an extensive breast and prostate cancer program to boot, kicked in some funds, and the research kicked up a notch.
"We wanted to see if we could get the same results in an animal as we got in a petri dish, and we did — the first time an effect in animals has been documented," Murphy said.
Tumors in mice injected with breast cancer cells and treated with ginseng grew only half as big as they did in the mice that went without the herb.
"I think by itself, ginseng is probably not an effective treatment because it doesn't prevent the tumor from growing — it just slows the rate of growth, and if you take the animal off the ginseng, the tumor will come back," Murphy said.
"But if you can slow the growth, maybe you can use something else that will kill that tumor."
A few cautions are in order. For one thing, ginseng's powerful effects come not from a single compound within its botanical "drugstore" but from the whole shebang working together.
"You have to use the whole root," Murphy said. "The many compounds in ginseng interact with each other."
In addition, ginseng can have estrogen-like effects, which would seem to make it a huge no-no for women with cancers that thrive on estrogen. But the key lies in how it is prepared. Murphy and her associates found those estrogen-like effects in alcohol-based ginseng extracts but not in water-based extracts.
These days, with nearly half a million dollars in funding from the National Cancer Institute and the Penny Severns Breast and Cervical Cancer Fund, Murphy is looking into the possibilities of partnering ginseng with conventional chemotherapy.
"What we're finding is that when you give the mice ginseng in their drinking water and then you give them doxorubicin, the ginseng actually enhances the efficacy of the drug," she said.
"What is so cool about this is that the cancer cells we are using are resistant to chemotherapy drugs, which is a real problem for women with breast cancer because they often do eventually develop resistance. But when you start from Day One giving both ginseng and the drug together, there's no tumor growth at all. It has a profound effect."
Murphy and her research assistants are testing ginseng with other breast cancer drugs to see if they get the same results, but this early outcome has special meaning, she said.
"Doxorubicin is used in the treatment of lots of different cancers, not just breast cancer," Murphy noted. "Our work suggests that the combination approach might be useful in treating those other cancers as well."
Murphy and her students also are trying to find out if ginseng deserves its reputation for easing the side effects that often accompany chemotherapy. And they're working "like gangbusters" to find the "why" behind ginseng's overall magic.
"That's the key question right now because clinicians like to know how a drug works before they tell a patient to take it," Murphy said.
In the meantime, Murphy has found herself serving as a sort of unofficial ginseng ambassador.
"I get lots of e-mail from people who have cancer who want my opinion," she said.
"All I do is give them the facts. 'This is what we have seen, but there have been no clinical studies to date.' Then they come back and say, 'Well, would you take it?' and I say, 'Yes. Yes I would.'"
Serving others and leading in research, scholarly and creative activities are among the goals of Southern at 150: Building Excellence Through Commitment, the blueprint for the development of the University by the time it celebrates its 150th anniversary in 2019.
Root for a cure — In the “dirty lab,” where her team processes ginseng, Southern Illinois University Carbondale scientist Laura L. Murphy (left), student Christopher S. Krantz and technician Mandy L. King show the tools of their trade. Krantz, a senior in physiology from Arlington Heights, holds a ginseng extract; King, a research assistant, cradles a handful of the root itself. Early studies at SIUC show that ginseng can slow and sometimes stop the growth of cancer tumors.