Feverfew

קראתי שתמציות מהצמח Feverfew (שמשמש לטיפול במיגרנות) הראו יכולת להשמיד תאי גזע סרטניים - הסוג הכי בעייתי. מישהו יכול להגיד מה הידע הנוכחי בתחום מתוצאות ניסויים על בני אדם?

Invest New Drugs. 2004 Aug;22(3):299-305. Links Phase I dose escalation trial of feverfew with standardized doses of parthenolide in patients with cancer.Curry EA 3rd, Murry DJ, Yoder C, Fife K, Armstrong V, Nakshatri H, O'Connell M, Sweeney CJ. Department of Pharmacy Practice, Purdue University, Indianapolis, IN, USA. PURPOSE: Feverfew is a botanical product that contains parthenolide. Parthenolide has in vitro AND in vivo anti-tumor AND anti-angiogenic activity. Feverfew has been used extensively without any formal pharmacokinetic analysis. A Phase I trial was conducted to evaluate the pharmacokinetics AND toxicity of parthenolide given as a component of "feverfew." PATIENTS AND METHODS: Feverfew (Tanacet trade mark ) was administered as a daily oral tablet in a 28-day cycle. A starting dose of 1 mg per day was explored with subsequent dose escalations to 2, 3, AND 4 mg. Assessment of plasma pharmacokinetics was performed on patients accrued to the trial. Solid phase extraction AND mass spectroscopy were used to evaluate parthenolide plasma concentrations. The limit of detection for parthenolide in plasma was 0.5 ng/ml. Patients were evaluated for response after every two cycles. RESULTS: Feverfew given on this schedule had no significant toxicity, AND the maximum tolerated dose was not reached. When parthenolide was administered at doses up to 4 mg as a daily oral capsule in the feverfew preparation, there was not detectable concentration in the plasma. Because of this, parthenolide pharmacokinetics were not able to be completed. CONCLUSION: Feverfew, with up to 4 mg of parthenolide, given daily as an oral tablet is well tolerated without dose-limiting toxicity, but does not provide detectable plasma concentrations. Purification of parthenolide for administration of higher doses will be needed.

A daisy-like plant known as Feverfew, found growing wild across the British Isles, is the source of an agent that kills human leukaemia stem cells like no other single therapy, scientists at the University of Rochester Medical Center's James P. Wilmot Cancer Center have discovered. Their investigation is reported in the online edition of the journal Blood. It will take months before a useable, pharmaceutical compound can be made from parthenolide, the main component in Feverfew. However, UR stem cell expert Craig T. Jordan, Ph.D., AND Monica L. Guzman, Ph.D., lead author on the Blood paper, say their group is collaborating with University of Kentucky chemists, who have identified a water-soluble molecule that has the same properties as parthenolide. The National Cancer Institute has accepted this work into its rapid access program, which aims to move experimental drugs from the laboratory to human clinical trials as quickly as possible. "This research is a very important step in setting the stage for future development of a new therapy for leukaemia," said Jordan. "We have proof that we can kill leukaemia stem cells with this type of agent, AND that is good news." Parthenolide is the first single agent known to act on myeloid leukaemia at the stem-cell level, which is significant because current cancer treatments do not strike deep enough to kill mutant cells where the malignancy is born. In other words, even the most progressive leukaemia treatment, a relatively new drug called Gleevec, is effective only to a degree. It does not reach the stem cells, so, according to Jordan, "you're pulling the weed without getting to the root." Feverfew has been used for centuries as an herbal remedy to reduce fevers AND inflammation, to prevent migraine headaches, AND to ease symptoms from arthritis. A person with leukaemia, however, would not be able to take enough of the herbal remedy to halt the disease. Investigating stem cells that give rise to cancer is an urgent new initiative, as is identifying stem-cell treatments that might end the disease process. Jordan AND Guzman are among only a handful of stem cell biologists nationwide who are specifically studying cancer stem cells. In recent years, scientists have identified cancer stems cells in blood cancers AND in brain AND breast tumours, although the idea that cancer stems cells exist has been around for at least 40 years. In the current study, the UR group began investigating Feverfew after other scientists showed that it prevented some skin cancers in animal models. Intrigued by the plant's anti-tumour activities, the UR team analysed how a concentrated form of parthenolide would act on the most primitive types of acute myelogenous leukaemia cells, chronic myelogenous leukaemia cells AND normal cells. In laboratory experiments, they also compared how human leukaemia stem cells reacted to parthenolide, versus a common chemotherapy drug called cytarabine. The result: parthenolide selectively killed the leukaemia cells while sparing the normal cells better than cytarabine. Scientists believe parthenolide might also make cancer more sensitive to other anti-tumour agents. And, the UR group was able to demonstrate the molecular pathways that allow parthenolide to cause apoptosis, OR cancer cell death, increasing the chances of developing a new therapy. The research is sponsored by grants from the Leukemia AND Lymphoma Society, American Cancer Society AND National Cancer Institute.