title: CD133 antigen expression in ovarian cancer.
abstract: BACKGROUND
  Much attention has been recently focused on the role of cancer stem cells (CSCs) in the initiation and progression of solid malignancies. Since CSCs are able to proliferate and self-renew extensively, thus sustaining tumor growth, the identification of CSCs through their antigenic profile might have relevant clinical implications. In this context, CD133 antigen has proved to be a marker of tumor cells with stemness features in several human malignancies.The aim of the study was to investigate the clinical role of the immunohistochemically assessed expression of CD133 in a large single Institution series of ovarian cancer patients.
  
  
  METHODS
  The study included 160 cases admitted to the Gynecologic Oncology Unit, Catholic University of Campobasso and Rome. CD133 antigen was identified by the monoclonal mouse anti-CD133-1 antibody (clone CD133 Miltenyi biotec).
  
  
  RESULTS
  In the overall series CD133 positive tumor cells were observed in 50/160 (31.2%) cases. A diffuse cytoplasmic pattern was identified in 30/50 (60.0%), while an apical cytoplasmic pattern was found in 20/50 (40.0%) of CD133 positive tumors.As of September 2008, the median follow up was 37 months (range: 2-112). During the follow up period, progression and death of disease were observed in 123 (76.9%), and 88 (55.0%) cases, respectively. There was no difference in TTP between cases with negative (median TTP = 23 months) versus positive CD133 expression (median TTP = 24 months) (p value = 0.3). Similar results were obtained for OS. When considering the TTP and OS curves according to the pattern of CD133 expression, a trend to a worse prognosis for cases with diffuse cytoplasmic versus the apical cytoplasmic pattern was documented, although the statistical significance was not reached.
  
  
  CONCLUSIONS
  The immunohistochemical assessment of CD133 expression seems not to provide additional prognostic information in ovarian cancer patients. The role of the different pattern of CD133 immunoreaction deserves further investigation in a larger series.
authors: Gynecologic Oncology Unit, Department of Oncology, Catholic University, Campobasso, Italy. gabriella.ferrandina@libero.it
authors: Gabriella
authors: G
authors: Ferrandina
authors: Enrica
authors: E
authors: Martinelli
authors: Marco
authors: M
authors: Petrillo
authors: Maria Grazia
authors: MG
authors: Prisco
authors: Gianfranco
authors: G
authors: Zannoni
authors: Stefano
authors: S
authors: Sioletic
authors: Giovanni
authors: G
authors: Scambia
mesh_terms: D000071916:AC133 Antigen; D000368:Aged; D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry; D015703:Antigens, CD / Q000096:biosynthesis*; D019540:Area Under Curve; D018450:Disease Progression; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006023:Glycoproteins / Q000096:biosynthesis*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D051379:Mice; D008875:Middle Aged; D010051:Ovarian Neoplasms / Q000378:metabolism*; D010455:Peptides; D013997:Time Factors
chemical_list: D000071916:AC133 Antigen; D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D006023:Glycoproteins; C000606023:PROM1 protein, human; D010455:Peptides; C000606024:Prom1 protein, mouse