A plant compound in herbal medicines and used for thousands of years may be responsible for urinary tract cancers and kidney damage common in Asia.
Known as aristolochic acid, the ingredient is found in the plant Aristolochia, commonly known as birthwart. The vine is used to treat arthritis, gout and inflammation as well as a weight loss remedy.
Researchers scoured the exomes of 19 cancer patients exposed to aristolochic acid and 7 patients with urinary tumors but no known exposure to the herbal medicine.
The exome is part of the human genome that contains codes for functional proteins and can reveal particular mutations.
In this case, scientists were able to directly tie the protein fingerprints to urinary tumors in patients in the aristolochic acid group.
They found 753 mutations in the toxin-exposed group compared to just 91 abnormalities in the tumors of cancer patients who did not take the herbal remedies.
Bin Tean Teh of National Cancer Center Singapore is co-author of a study
that identified the genetic protein mutations in toxin-exposed participants.
Teh, in an interview with the journal Science Translation Medicine
, said aristolochic acid was a powerful carcinogen or cancer-causing substance.
“This carcinogen caused actually more mutations than say smoking-related lung cancer or even the ultraviolet radiation associated skin cancer, melanoma,” said Teh.
Health officials in many Western countries have long suspected that Aristolochic acid is a carcinogen, and banned its import.
The medicinal vine has also been found to be an environmental hazard, contaminating wheat fields in the Balkans, where it grows naturally.
Teh’s article, along with a second study on the cancer-promoting genetic mutations of aristolochic acid, are published in Science Translational Medicine.