HDAC4 and pachyonychia congenita: HDAC4: overexpressed in primary and recurrent prostate cancer compared to benign tissues. Higher expression in androgen-independent cell lines (PC3, DU145, and LNCaP-AI) compared to androgen-dependent cellsHDAC5: overexpressed in recurrent prostate cancer compared to primary PC (p = 0.004). Highest expression in LAPC4 cells (androgen-dependent)