GDNF and glioblastoma: To determine whether CBP recruited to CRE in GDNF enhancer II has the same functions, we used ChIP-PCR to measure CBP binding, histone H3 acetylation, and RNA polymerase II recruitment in the CRE of GDNF enhancer II and at the TSS in GBM and NB tissue and in U251 and NHA cells.