title: Molecular aspects of carcinogenesis in pancreatic cancer.
abstract: BACKGROUND
  Pancreatic cancer (PCa) is one of the most aggressive human solid tumors, with rapid growth and metastatic spread as well as resistance to chemotherapeutic drugs, leading rapidly to virtually incurable disease. Over the last 20 years, however, significant advances have been made in our understanding of the molecular biology of PCa, with a focus on the cytogenetic abnormalities in PCa cell growth and differentiation.
  
  
  METHODS
  A MEDLINE search and manual cross-referencing were utilized to identify published data for PCa molecular biology studies between 1986 and 2008, with emphasis on genetic alterations and developmental oncology.
  
  
  RESULTS
  Activation of oncogenes, deregulation of tumor suppressor and genome maintenance genes, upregulation of growth factors/growth factor receptor signaling cascade systems, and alterations in cytokine expression, have been reported to play important roles in the process of pancreatic carcinogenesis. Alterations in the K-ras proto-oncogene and the p16INK4a, p53, FHIT, and DPC4 tumor suppressor genes occur in a high percentage of tumors. Furthermore, a variety of growth factors are expressed at increased levels. In addition, PCa often exhibits alterations in growth inhibitory pathways and evades apoptosis through p53 mutations and aberrant expression of apoptosis-regulating genes, such as members of the Bcl family. Additional pathways in the development of an aggressive phenotype, local infiltration and metastasis are still under ongoing genetic research. The present paper reviews recent studies on the pathogenesis of PCa, and includes a brief reference to alterations reported for other types of pancreatic tumor.
  
  
  CONCLUSIONS
  Advances in molecular genetics and biology have improved our perception of the pathogenesis of PCa. However, further studies are needed to better understand the fundamental changes that occur in PCa, thus leading to better diagnostic and therapeutic management.
authors.affiliation: First Department of Surgery, Agia Olga Hospital, Athens 14233, Greece.
authors.forename: Alexandros
authors.initials: A
authors.lastname: Koliopanos
authors.forename: Constantinos
authors.initials: C
authors.lastname: Avgerinos
authors.forename: Constantina
authors.initials: C
authors.lastname: Paraskeva
authors.forename: Zisis
authors.initials: Z
authors.lastname: Touloumis
authors.forename: Dionisisa
authors.initials: D
authors.lastname: Kelgiorgi
authors.forename: Christos
authors.initials: C
authors.lastname: Dervenis
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000235:genetics; D015815:Cell Adhesion Molecules / Q000235:genetics; D002450:Cell Communication / Q000235:genetics; D002454:Cell Differentiation / Q000235:genetics; D049109:Cell Proliferation; D002471:Cell Transformation, Neoplastic / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D016207:Cytokines / Q000235:genetics; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D009361:Neoplasm Invasiveness; D010190:Pancreatic Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D000090063:Proto-Oncogene Mas; D015398:Signal Transduction / Q000235:genetics
chemical_list: D015815:Cell Adhesion Molecules; D016207:Cytokines; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas