Calcitriol deregulates AR signaling to inhibit prostate cancer progression in the TRAMP model

The mechanism of action of vitamin D in prostate cancer (PCa) remains poorly defined, with most mechanisms identified being highly cell type and model specific. One of the underlying factors for these diverse mechanisms may be the use of overly simplistic in vitro model systems to study the complex biology of vitamin D response. Here we use the more complex and in vivo transgenic adenocarcinoma of mouse prostate (TRAMP) model to better determine the mechanism by which vitamin D inhibits PCa growth. In these studies early stage TRAMP mice were treated ± 20μg/kg calcitriol (vitamin D) on a Monday/Wednesday/Friday schedule and tissue was procured 12 and 24 hours post treatment to assess changes in PCa transcriptomes using Affymetrix gene expression arrays. 15 total samples were analyzed. 10 week old TRAMP mice were treated IP ± 20 ug/kg calcitriol on a Monday/Wednesday/Friday (MWF) schedule, and prostate tissue was procured 12 (N=3, control; N=4, calcitriol) and 24 hours (N=4, control; N=4, calcitriol) post treatment for use in affymetrix studies.