title: Activated leukocyte cell adhesion molecule (CD166)--its prognostic power for colorectal cancer patients.
abstract: BACKGROUND
  The activated leukocyte cell adhesion molecule (ALCAM, CD166) has been reported to be involved in tumorigenesis of colorectal cancer (CRC) and to function as a cancer stem cell marker. Controversial data exist regarding the prognostic power of ALCAM expression in CRC. Here, we evaluate the expression of ALCAM in a cohort of CRC patients and its usage as a prognostic marker for survival.
  
  
  METHODS
  Tissue specimens from 299 patients with CRC treated between 1993 and 2006 were analyzed via ALCAM immunohistochemistry (clone MOG/07) using a tissue microarray. Results were correlated with clinical, histopathological, and patient survival data (Chi-square test, Kaplan-Meier analysis, and log-rank test, respectively). Multivariate analysis also was performed (Cox regression).
  
  
  RESULTS
  ALCAM is expressed in most primary (76%) and secondary (62%) CRC lesions (P = 0.014). Immunohistochemistry revealed an inverse association with tumor grading (P = 0.002) but not with any other clinical or histopathological data. Kaplan-Meier survival analysis revealed a significant overall survival benefit in the group of ALCAM-positive patients (P = 0.019). Multivariate analysis showed that ALCAM is an independent positive prognostic marker for overall survival (P = 0.023).
  
  
  CONCLUSIONS
  ALCAM expression is a positive prognostic marker for overall survival of CRC patients, and its detection might help to optimize the existing prognostic staging system. Elevated expression in higher differentiated tumors might indicate a potential role in the early steps of tumorigenesis, and its loss might be associated with reduced cellular adhesion, resulting in a higher metastatic potential of the tumor. Further studies must be conducted investigating these hypotheses.
authors.affiliation: Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg Eppendorf, Germany. m.tachezy@uke.uni-hamburg.de
authors.forename: Michael
authors.initials: M
authors.lastname: Tachezy
authors.forename: Hilke
authors.initials: H
authors.lastname: Zander
authors.forename: Florian
authors.initials: F
authors.lastname: Gebauer
authors.forename: Andreas
authors.initials: A
authors.lastname: Marx
authors.forename: Jussuf T
authors.initials: JT
authors.lastname: Kaifi
authors.forename: Jakob R
authors.initials: JR
authors.lastname: Izbicki
authors.forename: Maximilian
authors.initials: M
authors.lastname: Bockhorn
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D015816:Cell Adhesion Molecules, Neuronal / Q000378:metabolism*; D003106:Colon / Q000473:pathology; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D005260:Female; D005326:Fetal Proteins / Q000378:metabolism*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008099:Liver / Q000473:pathology; D008113:Liver Neoplasms / Q000378:metabolism / Q000473:pathology / Q000556:secondary; D008198:Lymph Nodes / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009362:Neoplasm Metastasis; D011379:Prognosis; D055815:Young Adult; D020410:Activated-Leukocyte Cell Adhesion Molecule
chemical_list: D015703:Antigens, CD; D014408:Biomarkers, Tumor; D015816:Cell Adhesion Molecules, Neuronal; D005326:Fetal Proteins; C105613:ALCAM protein, human; D020410:Activated-Leukocyte Cell Adhesion Molecule