http://www.peplin.com/pipeline-products.php

http://www.peplin.com/research.php

The likelihood of you getting skin cancer is linearly related to
your exposure to the sun. The treatment indicated above came from Australia
(this is the Oz Report, after all) and came from a herbal source: Euphorbia
peplus (radium weed), "a traditional remedy for skin lesions."

http://www.iewf.org/weedid/Euphorbia_peplus.htm

Folklore.