[Studies on c-myc gene expression and p16 gene inactivation in nasopharyngeal carcinoma]

The alterations of c-myc and p16 genes and their relationship with the development and progression of nasopharyngeal carcinoma were studied.

Sixty-nine biopsies of nasopharyngeal carcinoma were examined for the homozygous deletion methylation and reduced expression of p16, and the overexpression of myc family oncogenes using multiple PCR, restriction endonuclease coupled PCR, reverse transcriptase PCR and immunohistochemistry.

The homozygous deletion and methylation of p16 gene were found in 7 and 11 cases respectively. The total inactivation rate was 26.1% (18/69). The negative expression of p16, as shown by immunohistochemical examination was found in 42 out of 69 cases (60.9%). The overexpression of myc family oncogenes was found in 51 cases (73.9%).

It suggests that the inactivation of anti-oncogene p16 and the activation of myc family oncogene may play an important role in the development of nasopharyngeal carcinoma.