TMPRSS2 and posterior cortical atrophy: Our findings are of particular interest in light of the recent study by Rasool et al. demonstrating that phosphorylation of MED1 at T1457 upon androgen stimulation is essential for AR-mediated transcription in PCa cells, i.e. the transcription of AR targets genes (e.g. KLK3, TMPRSS2) and oncogenic drivers (e.g. ERG and MYC) (7).