OBJECTIVETo examine the expression of cytochrome P450 related genes in oral submucous fibrosis tissue and to investigate the possible role of the genes in pathogenesis of oral submucous fibrosis (OSF).

METHODSBuccul mucosa tissues were obtained from OSF patients in early, medium and advanced stages, with each stage including 10 patients. Normal buccul mucosa tissues were collected from 10 patients undergoing oral and maxillofacial surgery as control. Oral submucous fibrosis-related genes were analysed by cDNA chips, and the results were submitted to the gene network database. Differentially expressed genes related to the pathway of CYP metabolism were indentifyed by the database analysis. Reverse transcription-polymerase chain reaction (RT-PCR) was used to verify the results from cDNA chips by increasing sample volume.

RESULTSThere were eight genes [CYP2B6, CYP2C18, CYP2F1, CYP3A5, microsomal glutathione S-transferase 2 (MGST2), alcohol dehydrogenase (ADH), UDP glucuronosyl transferase 2B15 (UGT2B15), ADH1C] which were related to the pathway of CYP metabolism. These genes were low expressed in all stages of OSF (P < 0.001).There were no differences in genes expression among the three stages of OSF (P > 0.05).

CONCLUSIONSThere were down-regulated genes related to the pathway of CYP metabolism in oral submucous fibrosis tissue. The ability of the pathway of CYP to metabolize and clear betel nut ingredients was reduced in OSF patients, which may play a role in the pathogenesis of OSF.