[1] Univ N Carolina, Lineberger Comprehens Canc Ctr, Chapel Hill, NC 27599 USA
[2] Univ N Carolina, Dept Genet, Sch Med, Chapel Hill, NC 27599 USA
[3] Univ N Carolina, Dept Radiat Oncol, Sch Med, Chapel Hill, NC 27599 USA
[4] Univ N Carolina, Dept Med, Sch Med, Chapel Hill, NC 27599 USA
[5] Univ N Carolina, Dept Pharmacol, Sch Med, Chapel Hill, NC 27599 USA
[6] Univ Nebraska, Med Ctr, Eppley Inst Res Canc & Allied Dis, Omaha, NE 68198 USA