HPSE and neuroblastoma: By using neuroblastoma cells as a model, Qu et al. found that the overexpression of miR-558 induced the expression of the heparanase (HPSE) gene, which was accompanied by a corresponding decrease of H3K9me2 and H3K27me3, and an increase of H3K4me3 and RNA Pol II on the HPSE promoter.