Yamanaka, Shinya

▪ 2009

born Sept. 4, 1962, Osaka, Japan

      In 2008 Japanese physician and stem-cell researcher Shinya Yamanaka advanced the front lines of stem-cell research yet again when he reported a new breakthrough in his research—the generation of induced pluripotent stem (iPS) cells from mouse liver and stomach cells. In 2006 Yamanaka had single-handedly revolutionized the field of stem-cell research when he first announced that he had succeeded in generating iPS cells. The cells had the properties of embryonic stem cells but were produced by inserting four specific genes into the nuclei of mouse adult fibroblasts (connective-tissue cells). The following year Yamanaka reported that he had derived iPS cells from human adult fibroblasts—the first successful attempt at generating human versions of these cells. This discovery marked a turning point in stem-cell research because it offered a way of obtaining human stem cells without the controversial use of human embryos. Yamanaka's technique to convert adult cells into iPS cells up to that time employed a retrovirus that contained a gene called c-Myc. This gene was believed to play a fundamental role in reprogramming the nuclei of adult cells. Yamanaka recognized, however, that the activation of the c-Myc gene during the process of creating iPS cells led to the formation of tumours when the stem cells were later transplanted into mice. He subsequently proceeded to create iPS cells without c-Myc in order to render the cells noncancerous and thereby overcome a major concern in the therapeutic safety of the iPS cells.

      Yamanaka received a medical degree from Kobe University in 1987 and a Ph.D. in pharmacology from the Osaka City University Graduate School in 1993. That year he joined the Gladstone Institute of Cardiovascular Disease, San Francisco, where he began investigating the c-Myc gene in specific strains of knockout mice (mice in which a specific gene has been rendered nonfunctional in order to investigate the gene's function). In 1996 Yamanaka returned to Osaka City University, where he remained until 1999, when he took a position at the Nara Institute of Science and Technology. During these years his research became increasingly focused on stem cells. In 2004 Yamanaka moved again, this time to the Institute for Frontier Medical Sciences at Kyoto University, where he began his landmark studies on finding ways to induce pluripotency in cells. Yamanaka again sought research opportunities in the United States. He subsequently was awarded funding that allowed him to split his time between Kyoto and the Gladstone Institute of Cardiovascular Disease. In 2007 Yamanaka became a senior investigator at the Gladstone Institute.

Kara Rogers

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