Waseda University in Tokyo is set to revoke the doctoral degree of Haruko Obokata, the biologist who rocked the scientific community by fabricating data during highly touted research on stem cells, sources familiar with the matter said Friday.

The former Riken researcher was last October given a year in which to correct a thesis she wrote in 2011. She failed to submit the revisions in time, the sources said, and a request for an extension was refused.

An investigation into data fabrication involving published papers on so-called STAP, or stimulus-triggered acquisition of pluripotency, revealed flaws in her work and generated suspicions the findings were faked. The method was touted as a simplified process for making stem cells, which can grow into any type of body tissue.

Obokata and her fellow researchers published the papers in the British science journal Nature in January 2014 and they were retracted in July the same year.

In April 2014, Riken found that Obokata had manipulated data for the STAP cell papers. That December, it said what was touted as STAP cell material was in fact likely derived from embryonic stem cells.

Waseda University, which set up a separate investigative panel to review her doctoral thesis, concluded the following July that her work contained copyright infringement and other errors.

The university also acknowledged there had been serious flaws in the guidance and screening process and reprimanded those responsible. It gave Obokata a one-year moratorium to correct her dissertation under adequate supervision.

The scandal has rocked the stem-cell research community and sparked a debate about research ethics.

Last month, seven laboratories in the United States, China, the Netherlands and Israel said they could not reproduce STAP cells using Obokata's declared technique despite more than 100 attempts.