The Expressions And Clinical Significance Of DPC4/Smad4 During Carcinogenesis Of Golden Hamaster Check Pouth

To investigate the expression of DPC4/Smad4 genes in malignant transformation of hamster buccal mucasa, so as to elucidate their role in squomous cell cancer's ocurring and development and their mutual relation.DPC4 gene is a alternated tumor restrained gene which was distilled from chromosome 18q21.1. DPC4 is the central molecule in the signal conducted pathway of TGF- ? super family. The death percent of DPC4 gene expresses higher in stomach-intertines tumor,but there is no report in the expression and function of oral mucosal squmous cell carcinoma and precancer.It is a signifucant scientific research way between suppressive-ongene and cell carcinogenesis. The main death form is gene imperfect and the mutation of gene,the representational of the later is the mutation of No.11 extron,which induce the lose of the extremity sequence of DPC4 and the function of this protein is get serious infection, so interdict the signal conduction pathway of TGF- ? super family,and it's function of restrainning the growth of cell, then the occurring of tumor is advanced.First,we established the animal model of malignant transformation in hamster buccal mucosa, and verified the result with histopathological method.HE staining showed a typical hyperplasia after 6 weeks of DMBA smearing, and most hamsters appeared characters of squamous cell carcinoma after 12 weeks of DMBA smearing. So the animal model was successful.Immunohistochemical staining shouwed that, from normal mucosa to simple hyperplasia, abnomal hyperplasia until the squamous cell carcinoma, the intensity and number of DPC4 positive cells gradually decreased,there are great difference of them.So we think DPC4 takes part in the occurs and development of oral mucosa carcinogenesis as a important control protein in G phase of cell.