Mao’s project recruited 500 scientists to find a new cure using two chief tactics: synthetic chemistry and ethnobotany based on traditional Chinese medicine. By analyzing ancient medical texts and more than 2,000 herbal remedies, the phytochemist Tu Youyou and her team identified a plant supposedly brimming with antimalarial compounds: sweet wormwood (Artemisia annua), a member of the daisy family that looks a bit like chamomile. Upon initial testing, the plant did not perform well. But a fourth-century handbook of prescriptions provided a vital insight: To extract the plant’s medicinal properties, it should be steeped in relatively cold water, rather than boiled like tea. Subsequent research identified wormwood’s primary active compound, which was eventually developed into artemisinin, one of the most successful treatments for malaria in history. In 2015, Tu received the Nobel Prize in Physiology or Medicine.

According to studies that were published in an issue of Life Sciences, artemesinin – a derivative of the wormwood plant used in Chinese Medicine – can kill 98% of breast cancer cells in less than 16 hours. The herb used alone caused a 28% reduction in breast cancer cells, but when paired with iron, sweet wormwood was able to eradicate cancer almost entirely. What’s more, normal cells were not negatively affected in the experiment by this treatment.

Artemisinin has been used in the past as a powerful anti-malarial herb, but it now has been proven to be a cancer-fighter, too. When subjects in the published study were given an iron supplement, which often accumulates in the breast tissue but especially so in cancerous cells, the artemisinin was able to selectively target ‘bad’ cells and leave ‘good’ cells alone.

“Taken together, our results demonstrate that the artemisinin disruption of E2F1 transcription factor expression mediates the cell cycle arrest of human breast cancer cells and represents a critical transcriptional pathway by which artemisinin controls human reproductive cancer cell growth.”

Read: Watercress Found to Block Breast Cancer Cell Growth

Iron accumulates in cancerous cells due to special receptors that help them in cell division, called transferrin receptors. Normal cells likely have these receptors as well, but cancerous cells have them in greater abundance, and thus can be targeted by the iron-artemisinin combination, like a 1-2 punch.

There have been many experiments now that prove this sweet wormwood derivative can effectively eradicate disease in the presence of iron. The extract has been used for thousand of years in China to treat malaria. The malaria parasite cannot live in the presence of artemisinin because they are iron-rich, but the treatment works just as well for cancerous cells, too. Bioengineers Henry Lai and Narendra Singh of the University of Washington, Seattle were the scientists who initially made this discovery. This is yet another example of a natural herb causing cancerous cell apoptosis.

While the sweet wormwood extract has been somewhat difficult to obtain for a fair price for countless years, it is now on its way to being mass-produced by biotech. Will the result be positive and promising?