title: Prostate transglutaminase (TGase-4, TGaseP) enhances the adhesion of prostate cancer cells to extracellular matrix, the potential role of TGase-core domain.
abstract: BACKGROUND
  Transglutaminase-4 (TGase-4), also known as the Prostate Transglutaminase, is an enzyme found to be expressed predominately in the prostate gland. The protein has been recently reported to influence the migration and invasiveness of prostate cancer cells. The present study aimed to investigate the influence of TGase-4 on cell-matrix adhesion and search for the candidate active domain[s] within the protein.
  
  
  METHODS
  Human prostate cancer cell lines and prostate tissues were used. Plasmids that encoded different domains and full length of TGase-4 were constructed and used to generate sublines that expressed different domains. The impact of TGase-4 on in vitro cell-matrix adhesion, cell migration, growth and in vivo growth were investigated. Interactions between TGase-4 and focal adhesion complex proteins were investigated using immunoprecipitation, immunofluorescence and phosphospecific antibodies.
  
  
  RESULTS
  TGase-4 markedly increased cell-matrix adhesion and cellular migration, and resulted in a rapid growth of prostate tumours in vivo. This effect resided in the Core-domain of the TGase-4 protein. TGase-4 was found to co-precipitate and co-localise with focal adhesion kinase (FAK) and paxillin, in cells, human prostate tissues and tumour xenografts. FAK small inhibitor was able to block the action mediated by TGase-4 and TGase-4 core domain.
  
  
  CONCLUSIONS
  TGase-4 is an important regulator of cell-matrix adhesion of prostate cancer cells. This effect is predominately mediated by its core domain and requires the participation of focal adhesion complex proteins.
authors.affiliation: Metastasis and Angiogenesis Research Group, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, UK. jiangw@cf.ac.uk.
authors.forename: Wen G
authors.initials: WG
authors.lastname: Jiang
authors.forename: Lin
authors.initials: L
authors.lastname: Ye
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Sanders
authors.forename: Fiona
authors.initials: F
authors.lastname: Ruge
authors.forename: Howard G
authors.initials: HG
authors.lastname: Kynaston
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Ablin
authors.forename: Malcolm D
authors.initials: MD
authors.lastname: Mason
mesh_terms: D002448:Cell Adhesion; D045744:Cell Line, Tumor; D002465:Cell Movement; D005109:Extracellular Matrix / Q000473:pathology*; D005455:Fluorescent Antibody Technique; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000378:metabolism; D006801:Humans; D016023:Integrins / Q000378:metabolism; D008297:Male; D051419:Paxillin / Q000378:metabolism; D011467:Prostate / Q000201:enzymology*; D011471:Prostatic Neoplasms / Q000201:enzymology / Q000473:pathology*; D011503:Transglutaminases / Q000737:chemistry / Q000378:metabolism*
chemical_list: D016023:Integrins; D051419:Paxillin; C418702:transglutaminase 4; D011503:Transglutaminases; D051416:Focal Adhesion Protein-Tyrosine Kinases