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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Androgen Antagonists, Androgens, Base Sequence, Blotting, Northern, Cell Division, DNA, Neoplasm, Dihydrotestosterone, Dose-Response Relationship, Drug, Down-Regulation, Epithelium, Flutamide, Gene Expression Regulation, Neoplastic, Humans, Male, Molecular Sequence Data, Polymerase Chain Reaction, Prostatic Neoplasms, RNA, Messenger, Receptors, Androgen, Transfection, Tumor Cells, Cultured.
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Is androgen independence of primary epithelial cultures of the prostate associated with a down-regulation of androgen receptor gene expression? Context: Epithelial cells cultured from prostatic acini do not demonstrate significant (P > 0.05) growth response to the testosterone metabolite dihydrotestosterone (DHT) at concentrations of 0.001-10.0 nM. In addition, the nonsteroidal antiandrogen hydroxyflutamide (HO-F) does not influence primary epithelial cell proliferation in this concentration range. Northern blotting carried out with an androgen reception (AR)-specific cDNA probe indicated that the extent of AR gene expression in six unpassaged primary prostatic epithelial cell cultures was insufficient to elicit a detectable signal upon autoradiography. However, RT/PCR analysis of total RNA using two sets of intron-spanning androgen receptor (AR) primers demonstrates the presence of full-length receptor transcripts in two BPH-derived epithelial cell cultures (BPH1 and BPH2) as well as a carcinoma-derived culture (CaP1). AR-positive LNCaP cells transfected with the AR reporter plasmid pMMTV/SPAP exhibit significant increases (P < 0.05) in SPAP production upon treatment with DHT. pMMTV/SPAP-transfected primary epithelial cells exhibit no such response when pulsed with either androgen or anti-androgen.
assistant
These results indicate that the lack of significant AR gene expression underlies the androgen independence of primary prostatic epithelial cell cultures. Final Decision: yes