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(WASHINGTON, February 3, 2009) - Green tea products have become regarded as a valuable health supplement, as studies have shown evidence of its benefit against a variety of diseases, including cancer. However, a new study suggests that some components of green tea may counteract the anticancer effects of one cancer therapy, bortezomib (Velcade®), and may be contraindicated for patients taking this medicine to ensure its maximum therapeutic benefit. This study is being prepublished online today in Blood, the official journal of the American Society of Hematology.

Below is a list of publications covering the research being done by UW and other institutions on artemisinin and cancer. The list is organized into two categories: publications related to the effects of artemisinin and its analogs on cancer and artemisinin pharmacology and pharmacokinetics. You may find them useful when consulting with your personal physician. We have also compiled a comprehensive list of artemisinin-related articles (more than 350 publications) that you may also find useful.

Artemisia Annua (Sweet Wormwood) is a shrubby perennial native to China. The leaf of the plant contains up to 0.04 percent Artemisinin. This herb has been used over the centuries by Chinese medical practitioners. Artemisinin came to the attention of the World Health Organization in the 1970s when Quinine lost efficacy against malaria. Artemisinin is the only drug effective against malaria and hundreds of millions of doses are prescribed for that purpose every year. The artemisinin molecule has an affinity for iron, which the malarial parasite sequesters internally. Artemisinin enters the malarial parasite and combines with sequestered iron to create Reactive Oxygen Species, rupturing the parasite. Like malarial parasites, cancer cells concentrate and sequester high levels of iron. Moreover cancer cells overexpress cell surface receptors for iron-containing compounds like ferritin and holotransferrin. Therefore, Artemisinin has a high affinity for cancer cells, and upon entering the cell combines with intercellular iron creating ROS-mediated apoptosis. Artemisinin is the only chemotherapeutic agent that lacks the tertiary amine necessary to usher the drug back out of the cell. This document is based on the research of Dr. Henry Lai and Dr. Narenda Singh at the University of Washington,and the medical practice of Dr. Ba Hoang of Vietnam and San Jose, California. There are a few points of divergence among experts studying Artemisinin, therefore more than one protocol is outlined below.

Artemisinin (pronounced /ɑːtə'misinən/) is a drug used to treat multi-drug resistant strains of falciparum malaria. The compound (a sesquiterpene lactone) is isolated from the plant Artemisia annua. Not all plants of this species contain artemisinin. Apparently it is only produced when the plant is subjected to certain conditions, most likely biotic or abiotic stress. It can be synthesized from artemisinic acid.[1] The drug is derived from a herb used in Chinese traditional medicine, though it is usually chemically modified and combined with other medications. Artemisinin is under early research and testing for treatment of cancer, primarily by researchers at the University of Washington.[7][8] Artemisinin has a peroxide lactone group in its structure. It is thought that when the peroxide comes into contact with high iron concentrations (common in cancerous cells), the molecule becomes unstable and releases reactive oxygen species. It has been shown to reduce angiogenesis and the expression of vascular endothelial growth factor in some tissue cultures.

Serum 25-hydroxyvitamin D and colon cancer: eight-year prospective study. Garland CF, Comstock GW, Garland FC, Helsing KJ, Shaw EK, Gorham ED. Lancet. 1989 Nov 18;2(8673):1176-8. PMID: 2572900 Blood samples taken in 1974 in Washington County, Maryland, from 25 620 volunteers were used to investigate the relation of serum 25-hydroxyvitamin D (25-OHD) with subsequent risk of getting colon cancer. 34 cases of colon cancer diagnosed between August, 1975, and January, 1983, were matched to 67 controls by age, race, sex, and month blood was taken. Risk of colon cancer was reduced by 75% in the third quintile (27-32 ng/ml) and by 80% in the fourth quintile (33-41 ng/ml) of serum 25-OHD. Risk of getting colon cancer decreased three-fold in people with a serum 25-OHD concentration of 20 ng/ml or more. The results are consistent with a protective effect of serum 25-OHD on colon cancer.