New Hope for Treating Cancer

Every cloud has a silver lining, even clouds of war and pestilence. Here’s an example. We can thank the Vietnam War and a malaria plague for the development of an herbal extract that may be your dog’s best new treatment for cancer. Thirty years ago, mosquitoes carrying malaria parasites bred in rain water that collected in underground tunnels built by the army of North Vietnam.

When that country lost more soldiers to malaria than to military weapons, it turned to China for help. Soon China’s top scientists were analyzing the problem from every perspective. When researchers at the Chinese Institute of Material Medicine discovered a region of China that did not have malaria, they found that its people drank a decoction (simmered tea) of Artemesia annua L. at the first sign of malarial symptoms. Artemesia annua L. is known as Qinghao in China and as sweet wormwood, annual wormwood, or sweet Annie in the West. (Its cousin Artemesia absinthium, or perennial wormwood, is an ingredient in herbal worming products for dogs and people.) In 1972, Chinese scientists isolated four chemical compounds in Artemesia annua: the natural compound artemisinin and three synthetic or semisynthetic compounds: artesunate, artemether, and arteether. Artemisinin became North Vietnam’s drug of choice for malaria. It has since become popular throughout Southeast Asia and Africa, where malaria is resistant to nearly all antimalarial drugs, including chloroquine, quinine, mefloquine, and Fansidar. So far, malaria has not developed resistance to artemisinin. In 1993, a University of Michigan researcher discovered the biochemical mechanism that makes artemisinin effective. Dr. Steven R. Meshnick, a parasitologist at the University of Michigan’s School of Public Health, found that the malaria parasite survives in its host by consuming approximately 25 percent of the hemoglobin in the host’s red blood cells. However, it does not metabolize the heme (iron) in the hemoglobin. Instead, it stores the iron in the form of a polymer, called hemozoin, inside a food vacuole. “We discovered that when artemisinin comes into contact with the iron in the hemozoin,” reports Dr. Meshnick, “the iron converts the artemisinin into a toxic chemical, releasing a free radical that destroys the parasite.” In Dr. Meshnick’s clinical study of 638 malarial patients in Vietnam, artemisinin eliminated 98 percent of malarial parasites within 24 hours and did so without significant side effects. “The parasite reappeared in only 10 to 23 percent of the group that took artemisinin for 5 to 10 days,” Dr. Meshnick says. “It may well be that the reappearance of the disease was due to a new infection rather than a flare-up of the prior one.” Artemisinin was equally effective against both the falciparum and vivax strains of malaria. Cancer needs iron, too Artemisinin’s reaction to iron molecules interested research professors Henry Lai, Ph.D., and Narendra Singh, MBBS, at the University of Washington in Seattle because cancer cells, like malaria parasites, collect and store iron. “Cancer cells need extra iron to replicate DNA when they divide,” explains Professor Lai. “As a result, cancer cells have a much higher concentration of iron than normal cells. When we began to understand how artemisinin works, I wondered if we could use that knowledge to target cancer cells.” In research published in 1995 in the journal Cancer Letters and in the November 2001 journal Life Sciences, Professors Lai and Singh found that artemisinin killed all of the human leukemia and breast cancer cells in a test tube within 8 to 16 hours while leaving nearly all of the normal cells unharmed. Artemisinin has been shown in test tube studies to be most effective against leukemia and colon cancer. Preliminary tests suggest that artemisinin will be effective against melanoma, breast, ovarian, prostate, renal, and central nervous system cancers such as glioblastoma and neuroblastoma. Working with veterinarians In 1999, Professors Lai and Singh pioneered canine research on artemisinin when, in collaboration with Tejinder Sodhi, DVM, of the Animal Hospital of Lynnwood in Lynnwood, Washington, they treated a male Golden Retriever with acute lameness of the right front leg. “The xray showed exostosis below the humeral neck with general sunburst osteolytic appearance,” reported Dr. Sodhi. “Fine-needle aspirate showed cells resembling osteoblasts and satisfied the criteria of malignancy.” Despite a very low dose of artemisinin and only 10 days of treatment (artemisinin was then expensive and the project lacked funding to buy more), the dog recovered within a week, gaining weight and walking normally, with xrays taken on the tenth day showing signs of bone remodeling. In another case, a seven-year-old male Basset Hound was diagnosed with lymphosarcoma of the lymph nodes. After three five-day treatments separated by intervals of three to five days, the diameter of the left and right linguinal and submandibular lymph nodes was reduced to half. Both dogs recovered without further treatment. As this article goes to press, the Washington Cancer Institute Department of Orthopedic Oncology at Georgetown University Medical Center, and a fellowship-trained veterinary surgical oncologist in Washington, DC, are collaborating on a project to determine whether artemisinin is an effective compound in the treatment of canine osteosarcoma. “We are performing in vitro or laboratory assays, the results of which will be determined by June 2003,” says Senior Clinical Researcher Kristen Kellar-Graney at the Washington Cancer Institute. “If these results prove favorable, it is our intention to perform a small, double-blinded, randomized study with pet canines who are not eligible for other forms of conventional treatment or pets whose owners are not interested in or cannot afford more conventional methods of treatment.” Using artemisinin The recommended human dose is approximately 1 milligram (mg) artemisinin per kilogram (2.2 pounds) of body weight twice per day. The dose recommended for most dogs is 50 mg or 100 mg twice per day for at least one month, continued for up to 6 to 12 months at a time.

Vitamin C, coenzyme Q10, pancreatic enzymes, and other supplements used in holistic cancer therapies are compatible with artemisinin, though some practitioners recommend separating artemisinin and high doses of vitamin C by at least three hours. Some healthcare practitioners recommend giving cod liver oil or other fat with artemisinin to improve its assimilation, but Professor Lai says that this is not necessary. Artemisinin should not be combined with radiation therapy because radiation treatments release iron stored in cancer cells to surrounding tissue. For best results, patients are encouraged to wait until at least two months after their last radiation treatment before beginning artemisinin. However, artemisinin is compatible with chemotherapy. In a study published last year, German researcher T. Efferth, Ph.D., tested artemisinin in combination with 22 chemotherapy drugs and found that artemisinin enhanced the drugs’ effectiveness. When artemisinin is used in combination with chemotherapy, it should be taken several hours after the chemotherapy treatment ends. When taken in combination with chemotherapy, artemisinin does not alleviate chemotherapy’s side effects. Cancer case history: Gus In the spring of 2002, Karen and Greg Moore of Bar Harbor, Maine, noticed that Gus, their seven-year-old German Shepherd Dog, was drinking large quantities of water and urinating more than usual. “He was having some accidents in the house,” Karen Moore recalls, “and he had never done that before. We went to the veterinarian, but it took quite a while to find out what the problem was. Only one of Gus’s lab tests showed an unusual result, and that was his calcium level, which was extremely high. At the end of April, our vet referred us to a clinic in Bath, Maine, where Gus underwent ultrasound and other tests.” The examination revealed apocrine gland adenocarcinoma, an anal gland tumor, with lymph node involvement. “The mass was then about the size of a plum,” says Moore, “and they could see that it had metastasized. The diagnosis was devastating. They basically had him dead and buried. They told us it was inoperable because it had already spread to the lymph nodes, there was nothing they could do, and he would die within a few weeks. They said we could try chemotherapy, but we would be fighting a very aggressive tumor, so it probably wouldn’t buy much time.” The Moores decided in favor of chemotherapy, and in May, Gus received his first of five treatments. “He couldn’t have more than that,” she says, “because they didn’t want it to affect his organs. In August, he had his final treatment, and that was that. He was still hanging in there. Now we were playing a wait-and-see game.” Three months later, while talking with the owner of a Bar Harbor health food store, Moore mentioned her dog. “I said I wished we could do something more for him,” she says. “That’s when the owner told me about the research of Dr. Henry Lai at the University of Washington. He gave me an e-mail address, and that’s how I got in touch with Holley Pharmaceuticals, the company that imports the artemisinin Gus takes.” On December 7, Gus received his first dose of artemisinin. “He’s taking 100 mg twice a day,” says Moore. “It’s been only three months so far, but we’ve been amazed at the improvements we see. His energy level is high, and his eyes are as clear as can be. They had gotten very foggy and unhealthy looking, but now they’re not cloudy at all. His calcium level went back to normal. The tumor grew after the chemotherapy treatments were stopped, but it hasn’t grown since we started the artemisinin. Gus is active, he plays ball, and he hikes with us. We really thought he would be slowing down by now. We never thought he would last this long or this well.” If Gus maintains his improved condition, Moore plans to continue his current dose of artemisinin. “On the protocol we’re following,” she says, “the dog takes it for up to a year and then you begin a weaning process and discontinue the treatment. Gus goes to the vet every six to eight weeks for checkups, so his condition is being monitored. It’s reassuring to have the vet keep an eye on him to be sure he’s doing well. Gus is now eight years old and thriving, which is something we never expected.” Cancer case history: Zoe Zoe, a Great Pyrenees, recently moved with Shirley and Mike Driggs to Lake Havasu City, Arizona. On April 19, 2002, when she was five and a half years old and they lived in Indiana, Zoe was diagnosed with osteo-sarcoma in her right front leg. “We took her to the vet because she was limping,” says Shirley Driggs. “The diagnosis was terrible news because bone cancer spreads really fast. Most dogs die within a month or two.” Driggs considered conventional treatments, including amputation, chemotherapy, and radiation. “From everything I could find about these options,” she says, “they only give dogs five or six more months of life, and the treatments’ side effects are so awful, the quality of that life is questionable at best. My mother died of bone cancer, so I’ve seen this disease up close. There was no way I could put Zoe through any of the conventional therapies.” Instead, she searched the Internet to learn everything she could about the disease. “On page after page and site after site,” she says, “I hit a message board that discussed artemisinin. Further searches led me to Dr. Lai. I called him up and discussed the herb, and he gave me some background information. I later e-mailed Dr. Lai with Zoe’s weight and medical background, and he advised me of the dosage he felt was suitable for her.” When Driggs returned to Zoe’s veterinarian with this information, he looked skeptical but said he had no problem with her trying it. “Since I had no other course of action,” she says, “and I was told this treatment had no adverse side effects, I thought, why not?!” Zoe’s response to artemisinin was immediate and dramatic. “We started her on 50 mg twice a day,” says Driggs, “and she literally quit limping on the second day. She ran, jumped, barked, played, fought with the other dogs, and had a wonderful time. You would never know she had bone cancer.” Zoe continued to be symptom-free for the next eight months. In fact, a radiograph taken last October showed that her bone tumor had begun to shrink. Two veterinarians examined her xrays and confirmed this. “When bone cancer metastasizes, it usually spreads to the lungs,” says Driggs, “and all of Zoe’s lung xrays, including one taken in February 2003, show that her lungs are completely clear. This has really amazed her doctors.” But in January 2003, just after the move to Arizona, Zoe’s limp came back. “We gave her a prescription anti-inflammatory,” says Driggs, “because we don’t want her to be in pain, but we knew this was a serious symptom.” Driggs contacted Dr. Lai, who recommended that they either stop the artemisinin for seven days and then continue at the same 50-mg dose twice a day, or increase the dose to 100 mg twice per day. They increased the artemisinin. On March 14, Driggs was petting Zoe when she noticed a hard, grape-sized lump under the dog’s left armpit. “We went straight to our veterinarian, who explained that what I found was a lymph node and that the cancer had spread,” explains Driggs. “But Zoe is still looking good. She is still eating well, still has her appetite, still comes outside, and still enjoys life. We’ll just take one day at a time.” In the meantime, Driggs says she is thoroughly satisfied with her experience using the artemisinin for Zoe’s cancer. “I have no regrets about having used it,” she says. “When your dog is diagnosed with bone cancer and you reject all conventional treatment, the odds are you won’t have more than a few weeks together. Instead of declining, Zoe has had a wonderful year. She may be living on borrowed time, but her borrowed time has stretched out considerably, and every day has been a blessing.”