AUSTIN, Texas (AP) -- A $3 billion cancer-fighting effort that's already under criminal investigation received yet more humiliation Wednesday when Texas Gov. Rick Perry called for a moratorium on new grants until confidence is restored in a once-celebrated agency that has plunged into turmoil in just three years.

Leaders of the Cancer Prevention and Research Institute of Texas quickly embraced the request from Perry, who unveiled the unprecedented state-run cancer fight in 2009 with promises of medical breakthroughs. But the effort has unraveled into one of Texas' biggest tempests involving a state agency in Perry's 12 years as governor.

A key Republican lawmaker who filed the original bill creating CPRIT piled on Wednesday by introducing new legislation, this time calling for new polices to bolster agency oversight and accountability. The agency also faces another round of scrutiny Thursday in front of a key state budget-writing committee.

"The mission of defeating cancer is too important to be derailed by inadequate processes and a lack of oversight," Perry said in a letter to CPRIT's oversight committee. That panel includes members appointed by Perry and some of his top political donors.

The governor added, "It is important that we restore the confidence of the Texas taxpayers who approved this important initiative before new funds are dispersed."

The letter was co-signed by Lt. Gov. David Dewhurst and state House Speaker Joe Straus, who also appoints members of the agency's governing board.

CPRIT controls the nation's second-largest pot of cancer research dollars, behind the National Institutes of Health. That federal department's cancer-research arm, the National Cancer Institute, also has said it is reviewing the troubles surrounding the Texas agency.

NCI confers on CPRIT prestigious status as an approved funding entity and losing that designation would be another blow for the beleaguered agency. It's already under a criminal investigation, is the target of widespread rebuke from scientists and has seen its leadership purged by resignations, including its executive director last week.

In a statement, oversight committee Chairman Jimmy Mansour and Vice Chairman Joseph Bailes said they agreed with Perry's call to cooperate with current reviews, implement recommended changes, enact reforms and fill key positions.

"These issues need to be resolved to restore public confidence in CPRIT," they said in a joint statement.

The reviews began after CPRIT disclosed that an $11 million grant to a private company had bypassed review.

The award to Dallas-based Peloton Therapeutics, a biomedical startup, marked the second time this year that a lucrative taxpayer-funded grant authorized by CPRIT instigated backlash and raised questions about oversight.

The first involved a $20 million grant to M.D. Anderson Cancer Center in Houston that CPRIT's former chief science officer, Nobel laureate Dr. Alfred Gilman, described as a thin proposal that should have first been scrutinized by an outside panel of scientific peer-reviewers, even though none was required under the agency's rules.

Dozens of the nation's top scientists agreed. They resigned en masse from the agency's peer-review panels along with Gilman. Some accused the agency of "hucksterism" and charting a politically-driven path that was putting commercial product-development above science.

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