EN2 and pachyonychia congenita: To detect the subcellular localization of endogenous and exogenous EN2 in different types of PC cell lines, LNCap, DU145 and PC3 cell lines which represented different stages of PC were transfected with EN2-RFP-expressing plasmid and then detected by immunofluorescence using our homemade EN2 monoclonal antibody or its isotype control antibody.