Since VDUP1 is up-regulated by vitamin D, we may hypothesize that vitamin D may exert beneficial effects against NF1 tumours also by enhancing VDUP1 expression, opening the way to innovative therapeutic strategies in which vitamin D can be used in combination with other drugs, such as HDAC inhibitors, in order to increase VDUP1 expression, in turn promoting cell death of NF1 cancers. Here, HDAC9 is linked to neurofibromatosis type 1.