KCNN2 codes for a small conductance Ca2+-activated potassium channel involved in the regulation of the neuronal excitability [55], and, to our knowledge, we here show for the first time that this gene is overexpressed in PCa harboring ERG rearrangements when compared to the other subtypes of PCa and to NPT. This evidence concerns the gene KCNN2 and posterior cortical atrophy.