Genome-wide maps of the androgen receptor and H3K27 upon MED19 overexpression in LNCaP cells

We report the application of ChIP and RNA sequencing to identify the mechanism whereby stable overexpression of MED19 in androgen-dependent LNCaP cells promotes growth under conditions of androgen deprivation. We determined the MED19 and AR transcriptomes and cistromes in control and MED19 LNCaP cells. We also examined genome-wide H3K27 acetylation in both the absence and presence of androgens. We found that MED19 overexpression selectively alters AR occupancy, H3K27 acetylation, and gene expression. Under conditions of androgen deprivation, genes regulated by MED19 correspond to genes regulated by ELK1, a transcription factor that binds the AR N-terminus to induce select AR target gene expression and proliferation. This study provides important insight into the mechanisms of prostate cancer cell growth under low androgen, and underscores the importance of the MED19 in this process. Overall design: Examination by CHIP seq of AR, MED19 and H3K27ac in contorl LNCaP and MED19 LNCaP cells with and without androgen treatment. Also performed RNA seq in contorl LNCaP and MED19 LNCaP cells with and without androgen treatment.