Review. Animal models of carcinogenesis in the digestive system.

Digestive system malignancies are quite common, accounting for 25% of deaths from cancer in the European Union. Various etiological factors of carcinogenesis include hereditary mutations and susceptibility polymorphisms, inflammation due to infectious agents, environmental and dietary factors. Transgenic, knockout or mutant animal models are very useful in reproducing cancers of the digestive tract that occur in humans. They offer the opportunity to study the disease phenotype and the function of the underlying mechanisms of carcinogenesis. In addition, animal models are valuable tools in cancer treatment attempts with the combined use of gene targeting or chemotherapy. This review illustrates the importance of the numerous animal models that have been developed by various methods in order to study carcinogenesis in the digestive tract and test potential therapeutic treatments.

FGFR-2 and -3 play an important role in initial stages of oral oncogenesis.

BACKGROUND: FGFR-2 and FGFR-3 (fibroblast growth factor receptors) have been shown to play an important role in several processes including carcinogenesis. This study was designed to determine gradual FGFR-2 and FGFR-3 expression in sequential stages of oral carcinogenesis in an experimental animal system of Syrian golden hamsters. MATERIALS AND METHODS: Tissue sections ranging from normal mucosa to squamous cell carcinoma were studied using monoclonal antibodies against FGFR-2 and FGFR-3 proteins. RESULTS: A significant elevation was revealed in both FGFR-2 and FGFR-3 expression during the stages of dysplasia and early invasion, while in the later stages of oral carcinogenesis the expression of both FGFR-2 and FGFR-3 decreased although not significantly. CONCLUSION: Our findings indicate that FGFR-2 and FGFR-3 seem to play an important role in the initial stages of oral cancer progression.