More progress on the reprogrammed stem cell front. The Japanese scientist who discovered last year how to create cells with the same potentiality as embryonic stem cells has just published another important article in the leading journal Science. It had been feared that these induced pluripotent stem cells (iPS cells) would cause cancer, but Shinya Yamanaka (pictured) has now shown that this is unlikely, at least in some cases.

His team reprogrammed adult mouse cells into iPS cells by introducing three new genes with a retrovirus. Mice injected with these cells have remained cancer-free for six months. Yamanaka’s breakthrough experiment reprogrammed skin cells, but this paper focused on liver and stomach lining cells. It is still far too early for clinical applications, says Dr Takashi Aoi, one of Yamanaka's colleagues. “In order to apply this technology to clinics, we still have to study the safety of iPS cells in bigger animals such as monkeys. It will take years to do this.” ~ London Telegraph, Feb 14