Preclinical Evaluation of panobinostat and ONC201 for the treatment of diffuse intrinsic pontine glioma (DIPG)

Diffuse intrinsic pontine glioma (DIPG) also referred as paediatric high-grade glioma (pHGG) is a fast-growing and aggressive type of childhood brain cancer. Recent studies investigating the molecular pathogenesis of DIPG have identified new therapeutic targets, paving the way for a new line of drugs mainly HDAC inhibitors. However, despite long years of trials, no significant results have been generated yet. Panobinostat is a HDAC inhibitor that has shown promising preclinical cytotoxicity in DIPG but failed so far in clinical trials. This study aims to re-evaluate the efficacy of Panobinostat in DIPG in vitro using patient-derived DIPG cell cultures obtained directly from patients. ONC201 is another potentially effective drug in DIPG. This apoptotic agent has been considered in a few clinical trials in diffuse glioma including DIPG. Our results reveal a dose-dependent response to Panobinostat and ONC201 in DIPG cells. However, Panobinostat caused a significant reduction in the mean percentage cell viability at a lower concentration compared to ONC201. Panobinostat caused significant decreases in DIPG cell viability at concentrations greater than or equal to 0.002 μM (p