African Milkbush Plant May Cause Childhood Cancer describes how a bush used to make glue — and used by children to mold toys — switches on certain genes, allowing a virus to cause cancer:
A plant used in Africa to make glue and herbal remedies may be an important cause of the most common childhood cancer in Africa, scientists said on Tuesday.Children use the sap from the milkbush plant to make toys, but researchers believe exposure to the sticky liquid may make them more susceptible to the effects of a virus that causes Burkitt’s lymphoma, a tumor of the immune system.
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When they studied the impact of the sap on the virus in the laboratory, they discovered low concentrations switched on three genes that were important in various stages of the virus, allowing it to replicate, kill cells and infect new ones.