Chinese medicine has yielded a promising new approach for treating canine cancer.
Seattle scientists have shown that a compound extracted from the wormwood plant seeks out and destroys many types of cancer cells, while leaving healthy cells unscathed.
In laboratory experiments, the compound called Artemisinin killed virtually all human breast cancer cells in the test tube, reports Dr Henry Lai, a bioengineering researcher at the University of Washington.
Just as importantly, he says, nearly all of the normal cells exposed to it were still alive.
And a dog with osteosarcoma so severe that it couldn’t walk across the room made a complete recovery within five days of receiving the treatment. X-rays showed the animal’s tumor “had basically disappeared,” says Lai, adding that he believed the dog is still alive two years later.
“Not only does Artemisinin appear to be effective, but it’s very selective,” Lai says. “It’s highly toxic to the cancer cells, but has a marginal impact on normal cells.”
Where does it come from?
Artemesinin is extracted it from the plant Artemesia annua L., commonly known as sweet wormwood, and was used thousands of years ago for use in the treatment of malaria, Lai says.
After a “secret recipe” for the treatment was discovered on a stone tablet in the tomb of a prince of the Han Dynasty during an archaeological dig in the 1970s, artemisinin re-emerged as a therapy for the mosquito-borne disease, Lai recalls.
In fact, a purified form of the plant compound is now the drug of choice for treating malaria in many areas, particularly where chloroquine-resistant strains have emerged, he says.
There are other forms of the herb wormwood such as Artemisia absinthium (absinth sagewort or common wormwood) but they do not contain the active artemisinin compound. Even subspecies of Artemesia annua may contain different concentrations of artemisinin. The subspecia that gives the highest yield is found in southwestern China and Vietnam.
How it works
Experiments into why artemisinin works as an anti-malaria agent led to its tests as an anti-cancer drug.
The key turned out to be a shared characteristic of the malaria parasite and dividing cancer cells: high iron concentrations. When artemisinin — or any of its derivatives — comes into contact with iron, a chemical reaction ensues, spawning charged atoms that chemists call free radicals.
In malaria, the free radicals attack and bind with cell membranes, breaking them apart and killing the single-cell parasite. Cells, too, need iron to replicate DNA when they divide. And since cancer is characterized by out-of-control cell division, cancer cells have much higher iron concentrations than do normal cells.
On their surfaces, cancer cells also have more so-called transferrin receptors — cellular pathways that allow iron to enter — than healthy cells.
In the case of breast cancer, the cells have five to 15 times more transferrin receptors on their surface than normal breast cells, Lai says.
And so entered the dash of logic:
About seven years ago, Lai reasoned, why not target cancer cells with the anti-malaria treatment? Working with assistant research professor Narendra Singh, Lai devised a strategy and obtained funding from the Breast Cancer Fund in San Francisco. The work appears in the November issue of the journal Life Sciences.
In his experiments, Lai subjected sets of both breast cancer cells and normal breast cells to either:
- A compound known as holotransferrin, which binds with transferrin receptors to transport iron into cells and thus further increases the cells’ iron concentrations
- A water-soluble form of artemisinin
- or A combination of both compounds.
The Cancer Killer: Cells exposed to just one of the compounds showed no appreciable effect, Lai reports. But the response by cancer cells when hit with first holotransferrin, then artemisinin, was dramatic, he says. After eight hours, three-fourths of the cancer cells were obliterated. A mere 16 hours later, nearly all the cancer cells were dead. Just as importantly, he says, the vast majority of normal breast cells did not die, showing the safety of the treatment.
More potential …
The success is particularly noteworthy in that breast cancer cells that were resistant to radiation were utilized in the experiment, Lai adds.
“So that means this approach might work for cancer resistant to conventional therapy.”
More aggressive cancers such as pancreatic and acute leukemia — which are characterized by more rapid cell division and thus higher iron concentrations — respond even better, Lai says.
Raising The Iron – Then Kicking Out Canine Cancer with Artemisinin
In a separate study, the therapy eliminated leukemia cells in the test tube within eight hours.
The next step, according to Lai, is further animal testing, followed by human trials.
First the patient would be given iron supplements to raise iron concentrations in his or her cancer cells, he says, and then the compound would be given in pill form.
While human tests are still years away, the treatment could revolutionize the way some cancers — particularly aggressive, fast-growing ones — are approached if it lives up to its early promise, he adds.
So far, Artemesinin has been shown to prevent canine cancer cells from developing a resistance to its action, and reportedly has yielded often impressive results in treating a variety of cancers, including leukemia, breast, colon, prostate and brain cancer (including left frontal glioblastoma).
How to give Artemisinin
Artemisinin has two derivatives:
- Artesunate, which has a relatively short half-life
- Artemether, which may be a more effective derivative, because it stays in the body longer. It also may be more effective than Artemisinin alone in brain cancers, because it penetrates the blood-brain barrier more readily.
Both compounds can be given orally.
Let your dog drink plenty of fresh water during therapy and provide plenty of pleasant, playful exercise, particularly after dinner for 2 to 3 hours.
NOTE: Inactive and old pets with poor health may respond poorly to treatment.
Iron supplements are NOT necessary. Avoid iron rich food, such as meat, 3 to 4 hours before the dose. It may be best to have your dog evaluated before and after his treatment (ultrasound, biopsy, X-rays and etc.) to see if the treatment is effective.
When Artemisinin was tested with monkeys, they showed no toxicity after they received up to 292 mg/kg (642 mg/pound) of Artemether over 1 to 3 months. Animal research has shown neurotoxic results with massive doses of Artemether – 150mg/kg/day (330mg/pound). Generally, at the lower recommended doses of 2-16 mg/pound, there is no reported toxicity.
The dose is typically 1 milligram of artemether per kg body weight per day, preferably given with butyrate and vitamin D-3. However, many holistic vets have doubled this dose with good results.
According to Dr Singh, when giving Artemix, calculate the dose based on artemether contents (1mg/kg/day) to avoid toxicity issues. Artemisinin and artesunate are very safe so you only need to be careful with the artemether.
According to Dr Singh, treatment should be continued daily for 8 weeks. If a response is noted (by a reduction of symptoms, signs, MRI, CAT), then switch to alternate days for 3 to 4 months. If no response is seen in 8 weeks, it might be best to switch to another therapy.
- Pets should not have radiation two months prior to using Artemisinin.
- To give the Artemesinin, suspend the contents in whole milk or yoghurt and, if necessary, deliver with a syringe.
- Alternately, you can give it orally by wrapping the capsules in cottage cheese.
- It’s important that Artemisinin is given 3 to 4 hours after dinner.
- Give your dog butyrate with vitamin D-3 at the same time he is given the Artemix or Artesinin.
- Low doses of antioxidants, specifically, 250 mg of vitamin C and 200 units of vitamin E, should be added around breakfast and lunch, but not given at the same time as the Artemisinin, according to Dr Singh.
Canine cancer and Artemisinin looks promising as a more natural alternative to chemotherapy or radiation therapy. If your dog suffers from cancer, this might be an important substance to discuss with your holistic vet.
Alternately, there is a yahoo chat group for canine cancer using Artemisinin. Sometimes, having the experience of other pet owners who have been in your shoes has a lot of value.
There’s always hope for dogs diagnosed with canine cancer with artemisinin . It is up to us to determine what treatments we are willing to use and how far we will go to help our pets. Artmesinin looks to be a safe and often effective choice for dog owners who want to think outside the box.