HDAC8 and osteosarcoma: This finding refutes a role for the epigenetic repression of Notch1 gene expression that was reported in valproic acid-treated osteosarcoma cells [22], and is consistent with the cytoplasmic localization of HDAC8 in MDA-MB-231 cells, irrespective of treatment with AR-42 (0.5 μM) (Figure 5B).