"The real battle starts here," Shinya Yamanaka speaks ahead of 20th anniversary of iPS cell papers

Ahead of the 20th anniversary of the publication of his papers on the generation of induced pluripotent stem cells (iPS cells), Kyoto University Professor Shinya Yamanaka gave a lecture on May 27 at the Japan National Press Club in Tokyo. In March, the Ministry of Health, Labour and Welfare (MHLW) conditionally approved production and sales of two products using iPS cells. In response to these achievements, Yamanaka stated, "It is wonderful that clinical development has come this far, but the real battle starts here."

Yamanaka generated iPS cells from mouse cells in August 2006 and successfully generated them from human cells in November 2007, publishing papers for each that attracted global attention. In 2012, he received the Nobel Prize in Physiology or Medicine.

Yamanaka began his lecture, titled "20 years since the publication of the iPS cell papers: The path toward practical application," by emphasizing that groundbreaking achievements were made possible by the young researchers and students who studied alongside him. He introduced how things began from a small laboratory and led to the establishment of the Center for iPS Cell Research and Application (CiRA) at Kyoto University, which holds a mission for practical applications to reach patients rather than just basic research, producing successive global achievements.

He then explained that turning iPS cells derived from human skin or blood into nerve cells, cardiac muscle cells, liver cells, and muscle cells leads to two medical applications: "regenerative medicine" and "drug discovery." In his explanation of regenerative medicine, Yamanaka emphasized that it is "in a sense, a technology like a time machine." This is because even if a patient is 60 or 80 years old, the nerve or heart cells made from iPS cells are practically zero years old. Making zero-year-old cells allows for the creation of healthy cells from before the onset of the disease. For example, iPS cells are used to create brain cells of Parkinson's disease patients and returned to their brains to regenerate functions.

Regarding drug discovery, he explained that by culturing iPS cells in laboratories at universities and pharmaceutical companies, "we can actually observe the moment a disease develops right before our eyes. We can reproduce the disease as if rewinding a tape recorder, and this becomes a disease model." Utilizing this disease model makes it possible to stop or delay the progression of a disease.

As a representative example of drug discovery research, he introduced research on amyotrophic lateral sclerosis (ALS). ALS is an intractable disease in which motor neurons gradually die, and there had been no effective therapeutic drug for many years. In many cases, it is characterized by taking a long time for symptoms to appear, making observational studies for progressive treatment difficult. He stated that when motor neurons were made from patient-derived iPS cells, the phenomenon of nerve cells actually dying inside a Petri dish could be reproduced within a short period. "Because we can make hundreds of Petri dishes containing patient-derived motor neurons, it became possible to test the effects of hundreds of drugs at the same time."

Yamanaka further introduced that more than 15 clinical studies and clinical trials are underway in Japan. Specifically, targeted diseases in drug discovery include Alzheimer's disease, ALS, and fibrodysplasia ossificans progressiva (FOP). In regenerative medicine, treatments target age-related macular degeneration, type 1 diabetes, corneal epithelial stem cell deficiency, as well as cancer treatments such as head and neck cancer.

He pointed out, "After 20 years, Japan is number one, but the United States and China are advancing regenerative medicine at a tremendous pace." He also noted, "The characteristic and strength of Japan is that the country's institutions and universities become 'One Team' to cooperate, advancing research and development for various types of diseases and injuries simultaneously."

Then, comparing the journey to his hobby of running marathons, he said, "We have finally reached the halfway point, but there is still half left. The second half of a marathon is difficult, and as the finish line approaches, more people drop out. We want to put forth our maximum effort and work hard through the second half of the race." He added, "The competition against the U.S. and China is fierce, and whether we can maintain an 'All-Japan' framework in the future is the most important factor."

Yamanaka began running seriously in the late 2000s and has participated in full marathon events as a citizen runner for over 10 years. Recently, he has been running in well-known full marathon events both domestically and internationally for the purpose of raising research funds. He has left excellent records for a citizen runner in his 60s, with reports noting that he finished the 2025 Beppu-Oita Mainichi Marathon with a personal best of 3 hours, 20 minutes, and 32 seconds. In his lecture on this day, he also revealed that he participated in a marathon event held in London in April.

On March 6, the MHLW conditionally approved "ReHeart" and "Amshepli." ReHeart was developed by the Osaka University-born venture "Cuorips Inc." (Tokyo) for patients with severe heart failure caused by ischemic cardiomyopathy. Amshepli was developed for Parkinson's disease patients by Sumitomo Pharma Co., Ltd. (Osaka), a research and development-oriented pharmaceutical company within the Sumitomo Chemical Group. Although conditional, this was the world's first approval of pharmaceutical products utilizing iPS cells.