FOXA1 and pachyonychia congenita: We next investigated FOXA1 mRNA and protein expression in PC by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis and Western blotting respectively, of four PC-derived cell lines, including androgen independent cell line (PC-3 and DU145), androgen sensitive cell line (LNCaP), androgen insensitive cell line (C4-2) established from castrated host of LNCaP and non-tumorigenic prostate cell line (RWPE-1) [16]–[19] (Figure 2A).