Tokyo's Waseda University said Monday it has revoked the doctorate of cell scientist Haruko Obokata, formerly of the prestigious Riken research institute, because she failed to correct inaccuracies in her thesis as requested.

Waseda President Kaoru Kamata told a news conference that Obokata is losing the Ph.D. in engineering conferred on her in 2011.

Although Obokata's doctoral research for the dissertation was published based on what she studied while at Harvard University, "the cooperation with our supervisors and outside institution was inadequate," Kamata said.

Obokata made headlines in 2014 when a team she led published purportedly groundbreaking research in the science journal Nature in which she described creating cells that serve as the building blocks of mammalian tissue, stimulus-triggered acquisition of pluripotency cells, or STAP cells.

Questions were asked, inconsistencies were identified and in December a Riken investigation concluded that the cells were in fact embryonic stem cells — obtained from another source.

The papers were retracted, rocking the scientific world and causing deep humiliation for Riken.

Meanwhile, the reputation of Waseda, too, has suffered damage. One of the nation's most highly respected private academic institutions, it now bears the shame of admitting it endorsed Obokata's dissertation in 2011 despite later identifying it as possibly riddled with errors.

In October 2014, the university's investigative panel said her dissertation contained at least 26 problem areas, including copyright infringement. It blamed its own inadequate screening for endorsing a "problematic" body of work, and gave her a year to correct it.

Obokata subsequently asked for an extension, which the university refused.

Last month, seven laboratories in the United States, China, the Netherlands and Israel said they had tried more than 100 times to reproduce her purported STAP cell work by following the method she described. They failed.