Interestingly, GSPT1, a gene epigenetically silenced in a large fraction of localized PC, was expressed highly in the 4 NR tumors, and its expression was generally mutually exclusive with these 3 genes in the extended PDX cohort as well as in the clinical specimens, suggesting a potential biological role of GSPT1 in resistance to SPT therapy. Here, GSPT1 is linked to pachyonychia congenita.