Biomaterial Database

Hedgehog/Gli supports androgen signaling in androgen deprived and androgen independent prostate cancer cells. 2010

Mengqian Chen, and Michael A Feuerstein, and Elina Levina, and Prateek S Baghel, and Richard D Carkner, and Matthew J Tanner, and Michael Shtutman, and Francis Vacherot, and Stéphane Terry, and Alexandre de la Taille, and Ralph Buttyan

The Ordway Research Institute, Albany, New York, USA.

BACKGROUND Castration resistant prostate cancer (CRPC) develops as a consequence of hormone therapies used to deplete androgens in advanced prostate cancer patients. CRPC cells are able to grow in a low androgen environment and this is associated with anomalous activity of their endogenous androgen receptor (AR) despite the low systemic androgen levels in the patients. Therefore, the reactivated tumor cell androgen signaling pathway is thought to provide a target for control of CRPC. Previously, we reported that Hedgehog (Hh) signaling was conditionally activated by androgen deprivation in androgen sensitive prostate cancer cells and here we studied the potential for cross-talk between Hh and androgen signaling activities in androgen deprived and androgen independent (AI) prostate cancer cells. RESULTS Treatment of a variety of androgen-deprived or AI prostate cancer cells with the Hh inhibitor, cyclopamine, resulted in dose-dependent modulation of the expression of genes that are regulated by androgen. The effect of cyclopamine on endogenous androgen-regulated gene expression in androgen deprived and AI prostate cancer cells was consistent with the suppressive effects of cyclopamine on the expression of a reporter gene (luciferase) from two different androgen-dependent promoters. Similarly, reduction of smoothened (Smo) expression with siRNA co-suppressed expression of androgen-inducible KLK2 and KLK3 in androgen deprived cells without affecting the expression of androgen receptor (AR) mRNA or protein. Cyclopamine also prevented the outgrowth of AI cells from androgen growth-dependent parental LNCaP cells and suppressed the growth of an overt AI-LNCaP variant whereas supplemental androgen (R1881) restored growth to the AI cells in the presence of cyclopamine. Conversely, overexpression of Gli1 or Gli2 in LNCaP cells enhanced AR-specific gene expression in the absence of androgen. Overexpressed Gli1/Gli2 also enabled parental LNCaP cells to grow in androgen depleted medium. AR protein co-immunoprecipitates with Gli2 protein from transfected 293T cell lysates. CONCLUSIONS Collectively, our results indicate that Hh/Gli signaling supports androgen signaling and AI growth in prostate cancer cells in a low androgen environment. The finding that Gli2 co-immunoprecipitates with AR protein suggests that an interaction between these proteins might be the basis for Hedgehog/Gli support of androgen signaling under this condition.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D011471	Prostatic Neoplasms	Tumors or cancer of the PROSTATE.	Cancer of Prostate,Prostate Cancer,Cancer of the Prostate,Neoplasms, Prostate,Neoplasms, Prostatic,Prostate Neoplasms,Prostatic Cancer,Cancer, Prostate,Cancer, Prostatic,Cancers, Prostate,Cancers, Prostatic,Neoplasm, Prostate,Neoplasm, Prostatic,Prostate Cancers,Prostate Neoplasm,Prostatic Cancers,Prostatic Neoplasm
D011944	Receptors, Androgen	Proteins, generally found in the CYTOPLASM, that specifically bind ANDROGENS and mediate their cellular actions. The complex of the androgen and receptor migrates to the CELL NUCLEUS where it induces transcription of specific segments of DNA.	Androgen Receptors,5 alpha-Dihydrotestosterone Receptor,Androgen Receptor,Dihydrotestosterone Receptors,Receptor, Testosterone,Receptors, Androgens,Receptors, Dihydrotestosterone,Receptors, Stanolone,Stanolone Receptor,Testosterone Receptor,5 alpha Dihydrotestosterone Receptor,Androgens Receptors,Receptor, 5 alpha-Dihydrotestosterone,Receptor, Androgen,Receptor, Stanolone,Stanolone Receptors,alpha-Dihydrotestosterone Receptor, 5
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000071676	Zinc Finger Protein GLI1	A transcriptional activator and oncogene protein that contains two CYS2-HIS2 ZINC FINGERS. Two isoforms are expressed; both regulate the expression of specific genes during development of craniofacial features, digits, the CENTRAL NERVOUS SYSTEM; and the GASTROINTESTINAL TRACT. They also regulate SONIC HEDGEHOG PROTEIN signaling and cell proliferation.	Gli Protein,Gli1 Protein,Glioma-Associated Oncogene Protein,Oncogene GLI Protein,GLI Protein, Oncogene,Glioma Associated Oncogene Protein,Oncogene Protein, Glioma-Associated
D000728	Androgens	Compounds that interact with ANDROGEN RECEPTORS in target tissues to bring about the effects similar to those of TESTOSTERONE. Depending on the target tissues, androgenic effects can be on SEX DIFFERENTIATION; male reproductive organs, SPERMATOGENESIS; secondary male SEX CHARACTERISTICS; LIBIDO; development of muscle mass, strength, and power.	Androgen,Androgen Receptor Agonist,Androgen Effect,Androgen Effects,Androgen Receptor Agonists,Androgenic Agents,Androgenic Compounds,Agents, Androgenic,Agonist, Androgen Receptor,Agonists, Androgen Receptor,Compounds, Androgenic,Effect, Androgen,Effects, Androgen,Receptor Agonist, Androgen,Receptor Agonists, Androgen
D014157	Transcription Factors	Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.	Transcription Factor,Factor, Transcription,Factors, Transcription
D014162	Transfection	The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.	Transfections
D014704	Veratrum Alkaloids	Alkaloids with powerful hypotensive effects isolated from American or European Hellebore (Veratrum viride Ait. Liliaceae and Veratrum album L. Liliaceae). They increase cholinergic and decrease adrenergic tone with appropriate side effects and at higher doses depress respiration and produce cardiac arrhythmias; only the ester alkaloids have been used as hypotensive agents in specific instances. They have been generally replaced by drugs with fewer adverse effects.	Alkaloids, Veratrum
D015153	Blotting, Western	Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.	Immunoblotting, Western,Western Blotting,Western Immunoblotting,Blot, Western,Immunoblot, Western,Western Blot,Western Immunoblot,Blots, Western,Blottings, Western,Immunoblots, Western,Immunoblottings, Western,Western Blots,Western Blottings,Western Immunoblots,Western Immunoblottings