Integration of cap analysis of gene expression and chromatin immunoprecipitation analysis on array reveals genome-wide androgen receptor signaling in prostate cancer cells.
The androgen receptor (AR) is a critical transcriptional factor that contributes to the development and the progression of prostate cancer (PCa) by regulating the transcription of various target genes. Genome-wide screening of androgen target genes provides useful information to understand a global view of AR-mediated gene network in PCa. In this study, we performed 5'-cap analysis of gene expression (CAGE) to determine androgen-regulated transcription start sites (TSSs) and chromatin immunoprecipitation (ChIP) on array (ChIP-chip) analysis to identify AR binding sites (ARBSs) and histone H3 acetylated (AcH3) sites in the human genome. CAGE determined 13 110 distinct, androgen-regulated TSSs (P<0.01), and ChIP-chip analysis identified 2872 androgen-dependent ARBSs (P<1e-5) and 25 945 AcH3 sites (P<1e-4). Both androgen-regulated coding genes and noncoding RNAs, including microRNAs (miRNAs) were determined as androgen target genes. Besides prototypic androgen-regulated TSSs in annotated gene promoter regions, there are many androgen-dependent TSSs that are widely distributed throughout the genome, including those in antisense (AS) direction of RefSeq genes. Several pairs of sense/antisense promoters were newly identified within single RefSeq gene regions. The integration of CAGE and ChIP-chip analyses successfully identified a cluster of androgen-inducible miRNAs, as exemplified by the miR-125b-2 cluster on chromosome 21. Notably, the number of androgen-upregulated genes was larger in LNCaP cells treated with R1881 for 24 h than for 6 h, and the percentage of androgen-upregulated genes accompanied with adjacent ARBSs was also much higher in cells treated with R1881 for 24 h than 6 h. On the basis of the Oncomine database, the majority of androgen-upregulated genes containing adjacent ARBSs and CAGE tag clusters in our study were previously confirmed as androgen target genes in PCa. The integrated high-throughput genome analyses of CAGE and ChIP-chip provide useful information for elucidating the AR-mediated transcriptional network that contributes to the development and progression of PCa.
Takayama
K
K
Department of Anti-Aging Medicine, Graduate School of Medicine, University of Tokyo, Bunkyo-ku, Tokyo, Japan.
Tsutsumi
S
S
Katayama
S
S
Okayama
T
T
Horie-Inoue
K
K
Ikeda
K
K
Urano
T
T
Kawazu
C
C
Hasegawa
A
A
Ikeo
K
K
Gojyobori
T
T
Ouchi
Y
Y
Hayashizaki
Y
Y
Aburatani
H
H
Inoue
S
S
D000107:Acetylation; D000728:Androgens / Q000494:pharmacology; D001665:Binding Sites / Q000235:genetics; D045744:Cell Line, Tumor; D047369:Chromatin Immunoprecipitation / Q000379:methods*; D013196:Dihydrotestosterone / Q000494:pharmacology; D020869:Gene Expression Profiling / Q000379:methods*; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D015894:Genome, Human / Q000235:genetics; D023281:Genomics / Q000379:methods; D006657:Histones / Q000378:metabolism; D006801:Humans; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D011401:Promoter Regions, Genetic / Q000235:genetics; D011471:Prostatic Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D011944:Receptors, Androgen / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics; D024363:Transcription Initiation Site
D000728:Androgens; D006657:Histones; D011944:Receptors, Androgen; D013196:Dihydrotestosterone