HDAC4 and prostate cancer: Halkidou et al. further demonstrated that castrate resistant prostate cancer expressed class II HDAC4 more predominately within the nucleus when compared to samples of benign prostate hyperplasia and androgen sensitive prostate cancers which maintained similar levels of HDAC4 expression within the cytosol, demonstrating a possible link between HDAC4 cellular location and loss of androgen sensitivity [14].