Japanese Nobel prize winner Shinya Yamanaka expressed his gratitude on Monday evening, saying that the award came as a surprise but the discovery must be further developed to apply to the medical field as early as possible, local press reported.

Kyoto University Professor Shinya Yamanaka, who shared the 2012 Nobel Prize in Physiology or Medicine with John B. Gurdon of the United Kingdom for the discovery that mature cells can be reprogrammed to become pluripotent, told a press conference in Kyoto University that he was a nameless researcher but the award was made as his country, his colleagues and students in the university, and his family members have long supported him and his work.

"I was given the prize today but this could not have happened without Professor Gurdon's pioneering early work and the distinguished achievement in his laboratory, and supports from my country.

"While it is moment of indescribable joy, I feel a strong responsibility for eventually providing practical use of the discovery for all patients who are waiting," Yamanaka said.

"The cultivation technique of inducible pleural potent stem cells (iPS cells) is very new and we need to continue to develop the method for medical as well as pharmaceutical research," Yamanaka added.