For example, AR activity in prostate cancer cells may be modulated by RNAs, including the long non-coding RNA (lncRNA) HOTAIR (Zhang et al., 2015), or by proteins, such as the transcriptional repressor RE1-silencing transcription factor (REST; also called neuron-restrictive silencer factor [NRSF]) (Svensson et al., 2014). Here, REST is linked to prostate cancer.