We thus, examined if HYP inhibits HDAC activity in GBM cell lines using two approaches: evaluating effects of HYP applied for 30 minutes onto whole cell lysates obtained from untreated cells, and a second approach of measuring total HDAC catalytic activity in lysates from cells pretreated with HYP (as live whole cells) for 72 hrs. Here, HDAC9 is linked to glioblastoma.