Human embryonic stem cells could be ideal for drug testing, say Israeli scientists. Karl Skorecki and Maty Tzukerman, of the Technion-Israel Institute of Technology, have found that injecting them into the hind legs of lab mice provides a platform for testing anti-cancer drugs in human tissue. In a study published in the April issue of Cancer Research, they described how the cells developed — as expected — into teratomas. Then they injected lab-grown cancer cells into the teratoma and these spread through the human tissue. They have already found one drug which is effective in cancers in ordinary mice, but not on the mice with human tissue.

Since a teratoma contains the entire “panoply of human cell types in a semi-organised fashion”, a range of drugs can be tested, days Dr Skorecki. “There are many uses of human embryonic stem cells as an experimental platform without ever injecting them into a human being,” he said. “This is just one example.”

“Long before embryonic stem cells are going to be used in clinical regenerative medicine, which is where all of the hope and some of the hype is, I think there is an opportunity to use embryonic stem cells for drug testing,” he told Seed magazine.