title: Active sonic hedgehog signaling between androgen independent human prostate cancer cells and normal/benign but not cancer-associated prostate stromal cells.
abstract: BACKGROUND
  Sonic hedgehog (Shh) signaling plays a pivotal role in stromal-epithelial interaction during normal development but its role in tumor-stromal interaction during carcinogenic progression is less well defined. Since hormone refractory prostate cancer with bone metastasis is difficult to treat, it is crucial to investigate how androgen independent (AI) human prostate cancer cells communicate with their associated stroma.
  
  
  METHODS
  Shh and its target transcription factor, Gli1 mRNA, were assessed by RT-PCR and/or quantitative RT-PCR in co-cultured cell recombinants comprised of AI C4-2 either with NPF (prostate fibroblasts from normal/benign prostate gland) or CPF (cancer-associated stromal fibroblasts) under Shh/cyclopamine (a hedgehog signaling inhibitor) treatment. Human bone marrow stromal (HS27A) cells were used as controls. In vivo investigation was performed by checking serum PSA and immunohistochemical staining for the apoptosis-associated M30 gene in mice bearing chimeric C4-2/NPF tumors.
  
  
  RESULTS
  We found that (1) Shh has minimal growth-stimulating effects on prostate cancer cells, but it stimulated the growth of NPF but not CPF; (2) active Shh signaling was found between AI C4-2 cells and NPF but not CPF; and (3) osteonectin (ON) is a Gli1 target gene in NPF and not in CPF, and ON up-regulation in NPF can be blocked by cyclopamine
  
  
  CONCLUSIONS
  Based on co-culture and chimeric tumor models, active Shh-mediated signaling was demonstrated between AI prostate cancer and NPF in a paracrine- and tumor progression-dependent manner. Our study suggests that drugs like cyclopamine that interfere with Shh signaling could be beneficial in preventing AI progression in prostate cancer cells.
authors.affiliation: Department of Urology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, Georgia, USA.
authors.forename: Katsumi
authors.initials: K
authors.lastname: Shigemura
authors.forename: Wen-Chin
authors.initials: WC
authors.lastname: Huang
authors.forename: Xiangyan
authors.initials: X
authors.lastname: Li
authors.forename: Haiyen E
authors.initials: HE
authors.lastname: Zhau
authors.forename: Guodong
authors.initials: G
authors.lastname: Zhu
authors.forename: Akinobu
authors.initials: A
authors.lastname: Gotoh
authors.forename: Masato
authors.initials: M
authors.lastname: Fujisawa
authors.forename: Jingwu
authors.initials: J
authors.lastname: Xie
authors.forename: Fray F
authors.initials: FF
authors.lastname: Marshall
authors.forename: Leland W K
authors.initials: LW
authors.lastname: Chung
mesh_terms: D000728:Androgens / Q000378:metabolism; D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology / Q000378:metabolism; D002450:Cell Communication / Q000187:drug effects / Q000502:physiology; D045744:Cell Line, Tumor; D002678:Chimera; D017077:Culture Media, Conditioned / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D053823:Hedgehog Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008297:Male; D051379:Mice; D008817:Mice, Mutant Strains; D019899:Paracrine Communication / Q000187:drug effects / Q000502:physiology*; D011467:Prostate / Q000166:cytology / Q000378:metabolism / Q000473:pathology; D011471:Prostatic Neoplasms / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D017154:Stromal Cells / Q000166:cytology / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014704:Veratrum Alkaloids / Q000494:pharmacology; D000071676:Zinc Finger Protein GLI1
chemical_list: D000728:Androgens; D017077:Culture Media, Conditioned; C400551:GLI1 protein, human; D053823:Hedgehog Proteins; C509239:SHH protein, human; D014157:Transcription Factors; D014704:Veratrum Alkaloids; D000071676:Zinc Finger Protein GLI1; C000541:cyclopamine