|By Wolfgang on Thursday, December 06, 2001 - 09:04 am: Edit|
Shit, you just broke the illusion we where planning to use as a justification to drink more absinthe! ;)
|By Don_Walsh on Thursday, December 06, 2001 - 07:26 am: Edit|
First of all this is A.annua not A.absinthium.
Secondly we have discussed A.annua and its various antimalarial/antiplasmodial components on thois forum several times.
The antineoplastic application is interesting but still in vitro only.
|By Dr_Ordinaire on Wednesday, December 05, 2001 - 11:04 pm: Edit|
Oh, shit, that was a moment of youthful enthusiasm...
The logistics are daunting.
Certifying prescriptions, being raided by the Feds...
Nah...go to SC
|By Dr_Ordinaire on Wednesday, December 05, 2001 - 11:01 pm: Edit|
I'm starting a "Medical Absinthe" Initiative right now...
|By Franglais on Wednesday, December 05, 2001 - 09:50 pm: Edit|
From today's MSNBC
Chinese folk remedy fights cancer
Plant compound sparks chain reaction that kills tumor cells
By Charlene Laino
Dec. 4 — Chinese folk medicine has yielded a promising new approach for treating cancer. Using a dash of logic and modern lab techniques, Seattle scientists have shown that a compound extracted from the wormwood plant seeks out and destroys breast cancer cells, while leaving healthy cells unscathed.
IN LABORATORY experiments, the compound killed within 16 hours virtually all human breast cancer cells exposed to it in the test tube, reports 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 a type of bone cancer known as 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 believes the dog is still alive two years later.
“Not only does [the drug] 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.”
So what is this “novel” anti-cancer compound? It’s called artemisinin — and actually, it isn’t new at all. Chinese folk practitioners extracted it from the plant Artemesia annua L., commonly known as wormwood, 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.
WHY 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, Lai says. 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.
THE ANTI-CANCER STRATEGY
The thrust of the strategy, according to Lai, is to pump up cancer cells with even more iron and then introduce artemisinin to selectively kill them.
In the 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.
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. By 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.
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.”
As might be expected, 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. In a separate study, the therapy eliminated leukemia cells in the test tube within eight hours, he says.
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.
If the treatment lives up to its early promise, it could revolutionize the way some cancers — particularly aggressive, fast-growing ones — are approached, he adds.
“The fascinating thing is that this was something the Chinese used thousands of years ago,” he adds. “We simply found a different application.”
The application certainly makes sense. There’s a wealth of research linking iron and cancer: One study, for example, showed that three times as much iron could be extracted from malignant breast tissue as from benign tissue, according to Ralph Moss, author of the “Healing Choices” reports for people with cancer. Elevated iron storage was found in 88 percent of the breast cancer patients studied.
Given this shared characteristic of malaria and cancer cells, why did it take so long to think of it? That, Lai says, is a mystery — “Maybe people just don’t think of simple ideas.”
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