MED1 and posterior cortical atrophy: Given that MED1 and AR interact not only in androgen-dependent PCa cells at SEs (7) but also in PCa tissues and that both these proteins are able to phase separate and form foci (14–16), it is likely that the partioning of AR and MED1, and other coactivators, to SEs in PCa is, at least in part, mediated by phase separation.