مري SCC در 05 مورد P35 بررسي شيوع پاپيلوما ويروس انساني تيپ 61 و 81 و تغييرات بيان پروتيين موتانت

Prevalence of human papillomavirus type 16 and 18 and p53 mutant protein expression in esophageal squamous cell carcinomas

Esophageal cancer is very common in some geographical regions of Iran. This area is referred to as the belt of esophageal cancer that extends from northern Iran to north of China. Human papilloma virus has been suggested as an etiologic factor for esophageal cancer. Many studies in the world, especially in regions with high prevalence, have shown the co-existence of this virus with esophageal squamous cell carcinoma (SCC).Paraffin-embedded archival tissues were collected for this research project, from 1997 to 2002, to evaluate the presence of HPV genome in samples from esophageal SCC. Simultaneously, the p53 mutant protein expression was assessed to find the relation between HPV infection and p53 mutant protein expression. For this study, 50 cases of esophageal SCC paraffin blocks from Ghaem University Hospital in Mashhad were chosen from 1997-2002. After DNA extraction, various genetic types of HPV genome (types 16 and 18) were detected using specific primers in a PCR assay. 8/45 testable cases (20 %) were positive for HPV type 16 and all the samples were negative for HPV type 18. P53 mutant protein was detected by Immunohistochemistry in 37/50 cases (74 %). Interestingly, all HPV positive samples were negative for p53 expression that was compatible with the reported HPV cancerogenesis. HPV E6 protein binds to and causes degredation of p53 protein exempting the deregulated cell to undergo p53-mediated control. Our results indicate that HPV may be a factor in pathogenesis of esophageal SCC. This project was supported by the research council of Mashhad University of Medical Sciences.