For instance, histone deacetylase (HDAC) 2 was reported to play significant regulatory roles in osteosarcoma cancer stem cells phenotype and in vivo cancer growth.9 Likewise, Jiang et al10 demonstrated that, histone methyltransferase SETD2 inhibited osteosarcoma cells growth and chemosensitivity. The gene discussed is PRDM9; the disease is cancer.