Codeletion of BRCA2 and RB1 was found in approximately 10% to 50% of PC patients, and the codeletion might be one of the resistance mechanisms in NHTs (44); the sensitivity to PARP inhibition was increased in this state, and the inhibition of PARP might have weakened the growth of mCRPC cells (44). Here, PARP1 is linked to pachyonychia congenita.