PC-3 cells with enhanced androgen receptor signaling: a model for clonal selection in prostate cancer.
BACKGROUND
Two sublines of the human prostate cancer cell line, PC-3, which is widely used as a model of prostate cancer progression, have been reported: PC-3(AR-) that do not express androgen receptor (AR), and PC-3AR+ that have measurable AR RNA but little protein.


METHODS
We assayed the geneotype, karyotype, AR expression, and physical characteristics of the two PC-3 sublines, and compared their ability to elicit a transactivation response from ectopic AR in the presence and absence of specific AR coregulators.


RESULTS
PC-3(AR-) and PC-3AR+ cells are genotypically and karyotypically similar, but exhibit salient differences in their morphology, growth rate, and expression of AR RNA. Whereas endogenous AR expression in PC-3AR+ cells does not result in sufficient protein to confer androgen responsiveness in culture, ectopic AR consistently elicited a much greater transactivation response in PC-3AR+ than in PC-3(AR-) cells, without altered sensitivity to activation by native ligand or AR coregulators including GRIP1, BRCA1, and Zac1. Moreover, phenotypic differences of AR variants implicated in prostate cancer susceptibility and progression were only observed in PC-3AR+ cells. Higher levels of known AR coregulator proteins detected in PC-3AR+ compared with PC-3(AR-) cells likely contribute to these differences.


CONCLUSIONS
These studies provide new evidence that the androgen-signaling axis can be sensitized in prostate cancer cells, and have important implications for the analysis and interpretation of AR structure and function in in vitro cell systems.
Buchanan
Grant
G
Dame Roma Mitchell Cancer Research Laboratories, Department of Medicine, University of Adelaide/Hanson Institute, Adelaide, Southern Australia, Australia.
Craft
Paul S
PS
Yang
Miao
M
Cheong
Albert
A
Prescott
Jennifer
J
Jia
Li
L
Coetzee
Gerhard A
GA
Tilley
Wayne D
WD
D002455:Cell Division; D003001:Cloning, Molecular; D018450:Disease Progression; D015972:Gene Expression Regulation, Neoplastic; D005838:Genotype; D006801:Humans; D007621:Karyotyping; D008297:Male; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000473:pathology*; D012313:RNA / Q000096:biosynthesis; D011944:Receptors, Androgen / Q000096:biosynthesis* / Q000235:genetics*; D015398:Signal Transduction; D014407:Tumor Cells, Cultured / Q000502:physiology*
D011944:Receptors, Androgen; D012313:RNA