From Traditional Chinese Herb to Targeted Modern Medicine
Artemisinin was discovered in 1972 by the Chinese scientist Youyou Tu, who extracted it from a traditional Chinese medicinal herb, sweet wormwood (Artemisia annua). Dr Tu was awarded a Nobel Prize in 2015 for her role in the discovery and development of this significant medicine. The active substance inhibits the malaria parasite and, in specific combination with other drugs, is the World Health Organisation’s recommended treatment for uncomplicated malaria . In these combination therapies, the artemisinin element rapidly kills the malaria parasite and is then quickly cleared from the body.
Since its discovery, artemisinin has been widely investigated for its anti-inflammatory and anti-cancer properties. It has been shown in clinical research that artemisinin and its derivatives selectively kill cancer tumour cells. How they are able to do this relates to the specific characteristics of cancer tumour cells compared with normal cells. Cancer cells have an increased metabolism and higher levels of iron intake, which they need in order to grow rapidly and multiply. Artemisinin is able to identify and target the iron receptors on these cells in order to attack and destroy the cell membranes, while healthy cells are left unharmed.
Effective in Multiple Cancer Types
Studies have been conducted in a variety of cancers, looking at tumour cell death and prevention of tumour cell migration (metastasis). A large trial programme conducted by the US National Cancer Institute and published in 2001 investigated the effect of one of the artemisinin derivatives, artesunate, on 55 different cancer cell types . The research found that the biggest benefit was in leukaemia and colon cancers. There was also significant effect on melanomas, breast, ovarian, prostate, CNS and renal cancers. Importantly, the artemisinin therapy was effective in leukaemia cells that were previously resistant to standard drug treatments.
More recent clinical trials have shown benefits in pancreatic and lung cancers, as well as confirming the previous results in multiple tumour types. Artemisinin has also been studied in metastatic and treatment-resistant cancers, with demonstrated benefits in limiting disease progression. Artemisinin has shown to be well tolerated and safe for use in a wide range of cancer patients. There is some evidence that higher doses may be more effective but this must always be balanced with the potential for side effects.
Combination therapy, where artemisinin is used alongside conventional chemotherapies, has been shown to have a synergistic effect in patients being treated for lung, ovarian, pancreatic and liver cancers.
Resources: Guidelines for the Treatment of Malaria (3rd ed). Geneva: World Health Organisation. 2015  Efferth T, Dunstan H, Sauerbrey A, Miyachi H and Chitambar CR: The anti-malarial artesunate is also active against cancer. Int J Oncol 18: 767-773, 2001