IFNG and neurofibroma: Interestingly, Choi et al.102 also discovered a switch from interferon (IFN) type I to type II signalling during the development of neurofibromas, which is consistent with the subsequent modulation of downstream targets of IFN-γ such as colony-stimulating factor (CSF)1.100,103 Remarkably, pegylated IFN-α2b significantly slowed down neurofibroma growth in some NF1 patients, warranting further investigation.104