title: Androgens regulate Hedgehog signalling and proliferation in androgen-dependent prostate cells.
abstract: Prostate cancer (PCa) is androgen sensitive in its development and progression to metastatic disease. Hedgehog (Hh) pathway activation is important in the initiation and growth of various carcinomas including PCa. We and others have observed aberrations of Hh pathway during the progression of PCa to the castration-resistant state. The involvement of androgen signalling in Hh pathway activation, however, remains largely elusive. Here we investigate the direct role of androgen signalling on Hh pathway. We examined the effect of Dihydrosterone (DHT), antiandrogen, bicalutamide, and Hh pathway inhibitor, KAAD-cyclopamine in four human prostate cell lines (two cancerous: LNCaP, VCaP, and two normal: PNT2 and PNT2-ARm which harbours a mutant version of androgen receptor (AR) that is commonly found in LNCaP). Cell proliferation as well as Hh pathway members (SHH, IHH, DHH, GLI, PTCH) mRNA expression levels were assessed. We showed that KAAD-cyclopamine decreased cell proliferation of DHT-stimulated LNCaP, VCaP and PNT2-ARm cells. SHH expression was found to be downregulated by DHT in all AR posititve cells. The negative effect of DHT on SHH expression was counteracted when cells were treated by bicalutamide. Importantly, KAAD-cyclopamine treatment seemed to inhibit AR activity. Moreover, bicalutamide as well as KAAD-cyclopamine treatments induced GLI and PTCH expression in VCaP and PNT2-ARm. Our results suggest that Hh pathway activity can be regulated by androgen signalling. Specifically, we show that the DHT-induced inhibition of Hh pathway is AR dependent. The mutual interaction between these two pathways might be important in the regulation of cell proliferation in PCa.
authors: INSERM, Unité 955, Créteil 94000, France.
authors: Nanor
authors: N
authors: Sirab
authors: Stéphane
authors: S
authors: Terry
authors: Frank
authors: F
authors: Giton
authors: Josselin
authors: J
authors: Caradec
authors: Mihelaiti
authors: M
authors: Chimingqi
authors: Stéphane
authors: S
authors: Moutereau
authors: Francis
authors: F
authors: Vacherot
authors: Alexandre
authors: A
authors: de la Taille
authors: Jean-Claude
authors: JC
authors: Kouyoumdjian
authors: Sylvain
authors: S
authors: Loric
mesh_terms: D000328:Adult; D000813:Anilides / Q000494:pharmacology; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002934:Cinnamates / Q000494:pharmacology; D013196:Dihydrotestosterone / Q000494:pharmacology; D053823:Hedgehog Proteins / Q000032:analysis / Q000502:physiology*; D006801:Humans; D008297:Male; D009376:Neoplasms, Hormone-Dependent / Q000473:pathology*; D009570:Nitriles / Q000494:pharmacology; D011471:Prostatic Neoplasms / Q000473:pathology*; D011944:Receptors, Androgen / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*; D014105:Tosyl Compounds / Q000494:pharmacology; D014704:Veratrum Alkaloids / Q000494:pharmacology
chemical_list: C542465:3-keto-N-aminoethylaminoethylcaproyldihydrocinnamoyl cyclopamine; C410798:AR protein, human; D000813:Anilides; D002934:Cinnamates; D053823:Hedgehog Proteins; D009570:Nitriles; D011944:Receptors, Androgen; C509239:SHH protein, human; D014105:Tosyl Compounds; D014704:Veratrum Alkaloids; D013196:Dihydrotestosterone; C053541:bicalutamide