title: S100 proteins as diagnostic and prognostic markers in colorectal and hepatocellular carcinoma.
abstract: BACKGROUND
  Clinical and experimental studies have suggested a link between S100 gene ex-pression and neoplastic disorders, however, the molecular mechanisms of this associa-tion are not well understood. The aim of this review was to conduct a comprehensive literature search in order to understand the possible underlying molecular mechanisms of this association. We also discuss their application as diagnostic and prognostic mark-ers in colorectal and hepatocellular carcinoma.
  
  
  METHODS
  We searched Pubmed (NLM) and Web of Science (ISI Web of Knowledge).
  
  
  RESULTS
  S100 genes display a complex expression pattern in colorectal and hepatocel- lular carcinoma. They are expressed in tumor and/or tumor stroma cells, and they exert both pro- and antitumorigenic actions. In view of this complexity, it becomes clear that S100 proteins might act as both friend and foe. The biological role of the S100 genes is predicted to depend on the relative contributions of the different cell types at specific stages of tumor progression.
  
  
  CONCLUSIONS
  Further research is required in order to uncover the functional role of S100 genes in tumorigenesis. Answers to this issue are needed before we can more fully un-derstand the clinical relevance of S100 protein expression within epithelial tumors, with regard to their potential applicability as biomarkers for diagnosis and therapy decisions.
authors.affiliation: Department of General Surgery, Division of Molecular Oncology and Immunotherapy, University of Rostock, Rostock, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Maletzki
authors.forename: Peggy
authors.initials: P
authors.lastname: Bodammer
authors.forename: Anne
authors.initials: A
authors.lastname: Breitrück
authors.forename: Claus
authors.initials: C
authors.lastname: Kerkhoff