OLIG2 and central nervous system cancer: OLIG2 is aCNS-restricted transcription factor that plays a critical role in glial progenitor proliferation36 and is ubiquitously expressed in gliomas.20,28,38 It can be used as aprognostic indicator as loss of expression has been linked to lower survival in humans.9 While the antibody for OLIG2 worked well on bovine brain tissue, only 4 outof 5 oligodendrogliomas showed the distinct nuclear immunolabeling.