AUSTIN, Texas (AP) - A top Republican says former leaders of a troubled $3 billion cancer-fighting agency in Texas won't publicly testify because of "significant legal concerns" raised by prosecutors.

House Appropriations Chairman Jim Pitts said Wednesday the request came from the Texas attorney general's office and Travis County public corruption prosecutors. Both began investigating the Cancer Prevention and Research Institute of Texas following an $11 million grant to a private company that skirted agency rules.

Pitts said former executive director Bill Gimson and chief scientific officer Alfred Gilman were willing to testify before prosecutors stepped in. Both resigned last year as problems within the agency mounted.

Neither has been accused of wrongdoing.

Lawmakers are vowing to reform the once-celebrated agency battered by controversial awards and state auditors exposing widespread problems with accountability.

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