title: Differential expression of C-CAM cell adhesion molecule in prostate carcinogenesis in a transgenic mouse model.
abstract: OBJECTIVE
  The transgenic adenocarcinoma of mouse prostate (TRAMP) model, in which various grades of prostate intraepithelial neoplasia (PIN) and prostate cancer with metastases can be reproducibly generated, is a paradigm for prostate disease progression. We have previously shown that C-CAM, an adhesion molecule, can suppress the growth of prostate cancer. In this report, we describe immunohistochemical characterization of differential expression of C-CAM at various stages of prostate tumorigenesis in the TRAMP model.
  
  
  METHODS
  We sampled prostate specimens and periaortic lymph nodes from TRAMP mice. Indirect immunohistochemical staining with a polyclonal anti-C-CAM antibody was performed on the formalin-fixed, paraffin-embedded specimens. After castration at 12 weeks of age, the TRAMP mice developed androgen-independent prostate cancer (AIPC) and lymph node metastasis at 18 to 24 weeks of age. Samples from these castrated mice were also analyzed.
  
  
  RESULTS
  C-CAM protein was expressed in the normal prostate epithelia of non-transgenic and TRAMP mice as well as in low-grade PINs in TRAMP mice. Expression was uniform on the luminal surfaces of these epithelia. C-CAM expression was noticeably reduced and the staining pattern heterogeneous in some high-grade PINs. C-CAM staining was generally absent in prostate cancer and metastatic lymph nodes. Androgen independent prostate cancer and its metastatic tumors generated in castrated TRAMP mice were also C-CAM negative.
  
  
  CONCLUSIONS
  C-CAM expression correlates with the differentiation states of prostate epithelia and is down regulated early in prostate tumorigenesis in the TRAMP model.
authors.affiliation: Department of Molecular Pathology, The University of Texas M.D. Anderson Cancer Center, Houston 77030, USA.
authors.forename: Y S
authors.initials: YS
authors.lastname: Pu
authors.forename: W
authors.initials: W
authors.lastname: Luo
authors.forename: H H
authors.initials: HH
authors.lastname: Lu
authors.forename: N M
authors.initials: NM
authors.lastname: Greenberg
authors.forename: S H
authors.initials: SH
authors.lastname: Lin
authors.forename: J R
authors.initials: JR
authors.lastname: Gingrich
mesh_terms: D000251:Adenosine Triphosphatases / Q000096:biosynthesis* / Q000235:genetics*; D000818:Animals; D015703:Antigens, CD; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000096:biosynthesis* / Q000235:genetics*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D006023:Glycoproteins; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D019048:Prostatic Intraepithelial Neoplasia / Q000235:genetics* / Q000378:metabolism*; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000378:metabolism*
chemical_list: D015703:Antigens, CD; C069847:CD66 antigens; C087701:Ceacam2 protein, mouse; D015815:Cell Adhesion Molecules; D006023:Glycoproteins; D000251:Adenosine Triphosphatases