title: Identification of a clinically relevant androgen-dependent gene signature in prostate cancer.
abstract: The androgen receptor (AR) is the principal target for treatment of non-organ-confined prostate cancer (PCa). Androgen deprivation therapies (ADT) directed against the AR ligand-binding domain do not fully inhibit androgen-dependent signaling critical for PCa progression. Thus, information that could direct the development of more effective ADTs is desired. Systems and bioinformatics approaches suggest that considerable variation exists in the mechanisms by which AR regulates expression of effector genes, pointing to a role for secondary transcription factors. A combination of microarray and in silico analyses led us to identify a 158-gene signature that relies on AR along with the transcription factor SRF (serum response factor), representing less than 6% of androgen-dependent genes. This AR-SRF signature is sufficient to distinguish microdissected benign and malignant prostate samples, and it correlates with the presence of aggressive disease and poor outcome. The AR-SRF signature described here associates more strongly with biochemical failure than other AR target gene signatures of similar size. Furthermore, it is enriched in malignant versus benign prostate tissues, compared with other signatures. To our knowledge, this profile represents the first demonstration of a distinct mechanism of androgen action with clinical relevance in PCa, offering a possible rationale to develop novel and more effective forms of ADT.
authors.affiliation: Department of Urology, Roswell Park Cancer Institute, Buffalo, New York 14263, USA. hannelore.heemers@roswellpark.org
authors.forename: Hannelore V
authors.initials: HV
authors.lastname: Heemers
authors.forename: Lucy J
authors.initials: LJ
authors.lastname: Schmidt
authors.forename: Zhifu
authors.initials: Z
authors.lastname: Sun
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Regan
authors.forename: S Keith
authors.initials: SK
authors.lastname: Anderson
authors.forename: Kelly
authors.initials: K
authors.lastname: Duncan
authors.forename: Dan
authors.initials: D
authors.lastname: Wang
authors.forename: Song
authors.initials: S
authors.lastname: Liu
authors.forename: Karla V
authors.initials: KV
authors.lastname: Ballman
authors.forename: Donald J
authors.initials: DJ
authors.lastname: Tindall
mesh_terms: D014408:Biomarkers, Tumor / Q000235:genetics*; D020869:Gene Expression Profiling; D006801:Humans; D007834:Lasers; D008297:Male; D042282:Microdissection; D009367:Neoplasm Staging; D020411:Oligonucleotide Array Sequence Analysis; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000473:pathology; D034741:RNA, Small Interfering; D011944:Receptors, Androgen / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D026362:Serum Response Factor / Q000235:genetics*; D014162:Transfection
chemical_list: D014408:Biomarkers, Tumor; D034741:RNA, Small Interfering; D011944:Receptors, Androgen; D026362:Serum Response Factor