title: Primary liver tumors: origin and target therapy.
abstract: BACKGROUND
  The liver is the largest gland and chief metabolic organ of the human body possessing a unique ability to regenerate. The general interest of primary liver tumors is noteworthy because of their increasing worldwide incidence and mortality. Recent studies have focused on the ancestors of mature hepatocytes, which are capable of proliferating, differentiating and self-renewing.
  
  
  OBJECTIVE
  To provide a brief and up-to-date review on the cellular origin of primary liver tumors and to examine the use of stem cells in potential future therapeutic attempts.
  
  
  METHODS
  A review of relevant literature.
  
  
  RESULTS
  It is clear that hepatic progenitor cells (HPCs) could be the basis of some hepatocellular carcinomas (HCC), cholangiocarcinomas (CHC), hepatocellular adenomas and hepatoblastomas. Cancer stem cell (CSC) theory emphasizes the role of hepatic stem cells in the development and progression of liver tumors.
  
  
  CONCLUSIONS
  The expression of HPCs markers may be used as new independent prognostic factors in HCC. Conventional treatments for HCC do not seem to be beneficial for the majority of patients and new therapeutic approaches such as gene therapy and targeted drug therapy are of great clinical interest.
authors.affiliation: University of Athens, Medical School, Department of Forensic Medicine and Toxicology, Goudi, Athens, GR11527, Greece.
authors.forename: Michail
authors.initials: M
authors.lastname: Papoulas
authors.forename: Stamatios
authors.initials: S
authors.lastname: Theocharis
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor / Q000235:genetics; D006528:Carcinoma, Hepatocellular / Q000235:genetics / Q000473:pathology* / Q000628:therapy*; D002454:Cell Differentiation / Q000235:genetics; D019070:Cell Lineage / Q000235:genetics; D002471:Cell Transformation, Neoplastic / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D018281:Cholangiocarcinoma / Q000235:genetics / Q000473:pathology / Q000628:therapy; D016503:Drug Delivery Systems / Q000379:methods*; D022781:Hepatocytes / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics / Q000473:pathology* / Q000628:therapy*; D013234:Stem Cells / Q000378:metabolism / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor