The Mutation And Overexpression Of P53 Gene, C-erbB-2 Gene, Bcl-2 Gene, C-myc Gene And Epstein-Barr Virus In Nasopharyngeal Carcinoma.

BACKGROUND Nasopharyngeal carcinoma (NPC), is a neoplasm of malignant epidermoid origin, one of the common malignant-neoplasm in China, of which the etiology and molecular tumorigenesis remain unclear, The etiologic factors identified for NPC include Epstein-Barr virus (EBV), environmental risk factors and genetic susceptibility.The evidence for the role of EBV and its potential interplay with environmental and genetic factors in NPC remains to be proved. With further investigation of oncogenes and tumor suppressor genes, the biological study on NPC is being done. The tumor suppressor gene p53 is without doubt the most frequently invloved in NPC. p53 gene mutations occur in approximately half of all human cancers. Wild-type p53 protein seems to act as a recessive tumor suppressor gene whereas mutant forms can behave as dominant oncogene. The c-erbB-2 on-coprotein is a 185 kD transmembrane protein homology to EGF receptor, promoting neoplasms proliferation, bcl-2 gene, an anti-apoptosis gene, will provide opportunity with chromosomal translocation, gene mutation and viral infection, etc. when overexpressed. The growth and metastasis of NPC will be enhanced by c-myc oncogene. Many researches have shown that the abnormality of these genes influences the survival.METHOD Immunohistologic staining for p53, c-erbB-2 and bcl-2 antibody, and in situ hybridization for EBV encoded mRNA (EBER) and c-myc were performed on archival material from 248 NPC patients.RESULTS p53 was overexpressed in 68.1% of NPC. No correlation was found between overexpression and clinical parameters. The survival rates were not different...