Plasma levels of Claudin 3 were subsequently determined using ELISA (n = 58 localized PC, n = 11 metastatic PC, n = 15 BPH, n = 15 healthy individuals), with increased level detected in GS ≥ 8 compared to BPH and GS ≥ 8 vs. GS6-7. Here, CLDN3 is linked to pachyonychia congenita.