Abstract: Objective　To study the mechanism of p16 gene inactivation in salivary adenoid cystic carcinoma.Methods　53 cases of freshly excised salivary adenoid cystic carcinomas were studied. Polymerase chain reaction (PCR) and single-stranded conformation polymorphism analysis of polymerase chain reaction products (PCR-SSCP) were used to detect deletion and mutation of p16 gene in salivary adenoid cystic carcinomas. Methylation specific PCR (MSP) was used to detect the methylation status of p16 gene.Results　The homozygous deletion, mutation and hypermethylation of p16 gene were noted in 16 cases (30·2%),4 cases (7·5%) and 26 cases (49·1%) respectively in 53 cases of salivary adenoid cystic carcinomas.Conclusion　The main in- activation mechanisms of p16 gene in salivary adenoid cystic carcinomawere hypermethylation and homozygous deletion. The muta- tion p16 gene was rare in salivary adenoid cystic carcinoma.

Key words: salivary gland adenoid cystic carcinoma, p16, deletion, mutation, methylation