The goal of our study was to perform a comprehensive analysis of the protein and mRNA expression, epigenetic and genetic changes of HNF1B in prostate carcinoma (PC), focusing also on its relationship with the possible upstream (EZH2) and downstream (ECI2) genes on the level of protein expression, as detected by immunohistochemistry and mRNA expression. The gene discussed is ECI2; the disease is pachyonychia congenita.