Observation of MAOA expression revealed that the lowest MAOA expression was observed in benign prostate tissues with only 10 (20%) specimens having high MAOA expression, and MAOA expression was higher in PC tissues with 46 of 115 (40%) low-intermediate risk PC specimens and 75 of 135 (55.6%) high risk PC specimens with high MAOA expression (Table 1). Here, MAOA is linked to pachyonychia congenita.