br in the genetic structure of
in the genetic structure of the AR locus, as well as the total amount and relative ratios of all AR isoforms, will dictate the prevalence of each AR dimer.
In this study, we propose that the repressive function of ARv7 acts by negatively regulating genes that limit CRPC proliferation. Specifically, we found that SLC30A7, B4GALT1, HIF1A, and SNX14 have a negative impact on cell growth, while being repressed by ARv7. Interestingly, three of these genes have been previously associated with tumor-suppressor activities. Specifically, SLC30A7 N-octanoyl-L-Homoserine lactone accelerates prostate tumor for-mation (Singh et al., 2016; Tepaamorndech et al., 2011) while SNX14 is commonly deleted in human cancers (Dong et al., 2008). Moreover, HIF1A, although primarily studied as an onco-gene, also has tumor-suppressive activity (Chiavarina et al., 2010; Velasco-Hernandez et al., 2014). In PCa patients, expres-sion of the four genes is negatively correlated with ARv7 protein levels and time to recurrence. This is consistent with the concept that ARv7 acts by repressing tumor-suppressive genes during PCa progression, and that expression of ARv7-repressed genes may serve as a biomarker to assess ARv7 inhibition.
Detailed methods are provided in the online version of this paper and include the following:
d KEY RESOURCES TABLE
d CONTACT FOR REAGENT AND RESOURCE SHARING d EXPERIMENTAL MODEL AND SUBJECT DETAILS
B Cell Lines
B Clinical Patient Samples d METHOD DETAILS
B Generation of Doxycycline-Inducible shARfl or shARv7 Cell Lines
B siRNA Transfection
B Cell Proliferation Assays B Tissue Microarray
B Protein Assays
B RNA-Sequencing (RNA-seq) B ChIP-Sequencing (ChIP-seq) B FRET and FRAP
B MARCoNI Assay B CRISPR Screen
d QUANTIFICATION AND STATISTICAL ANALYSIS B Tissue Microarray Analysis
B Patient Data Clustering and Analysis of Recurrence-free Survival
B Western Blot Quantification B RNA-seq Analysis
B ChIP-seq Analysis
B FRET and FRAP Analysis B MARCoNI Assay Analysis B CRISPR Screen Analysis
d DATA AND SOFTWARE AVAILABILITY
Supplemental Information includes six figures and six tables and can be found with this article online at https://doi.org/10.1016/j.ccell.2019.01.008.
DECLARATION OF INTERESTS
M.B. has been a consultant for GTx and Novartis. He receives sponsored research support from Novartis and serves on the Scientific Advisory Board of Kronos Bio. L.C. and A.C.G. are employees of Sanofi and Basilea Pharma-ceutica, respectively. The other authors declare no competing interests.
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