HIP1 goes nuclear to aid in androgen responses.
Adaptor proteins that mediate membrane trafficking have been implicated in cancers as signaling regulators; some are overexpressed in cancers, including prostate cancer. On
page 191, Mills et al. provide an unexpected explanation for these observations. They find that the adaptor protein HIP1 moves to the nucleus following androgen stimulation, where it enhances transcription from androgen-responsive genes.Previous work showed that overexpression of HIP1 in prostate cancer cells correlates with recurrence, but how HIP1 might affect androgen receptor function was unknown. Now, Mills et al. measure the amount of HIP1 and androgen receptor protein in the nuclei of tissue culture cells before and after androgen stimulation. As expected, most of the androgen receptor moved to the nucleus. So did 50% of the HIP1 protein.
The two proteins copurified by immunoprecipitation and both purified with androgen-responsive promoter elements in...
