Lack of correlation of betel nut chewing, tobacco smoking, and alcohol consumption with telomerase activity and the severity of oral cancer.

BACKGROUND Oral cancer is one of the most frequent cancers. A strong association has been found between oral cancer incidence and the use of betel nut, alcohol, and tobacco. Telomerase activity (TA) has also been shown to play a role in carcinogenesis. We therefore surveyed the consumption habits of betel nut chewing, alcohol drinking, and tobacco smoking in oral cancer patients and evaluated the association of these habits with TA level and clinical stage. METHODS In total, 154 oral cancer patients were recruited. TA was measured in paired (grossly normal and cancerous) tissues using a polymerase chain reaction-based enzyme immunoassay. Associations of these factors with clinical stage and TA level were analyzed using the Pearson chi-square test. RESULTS In these patients, 86.4%, 61.0%, and 83.3% used betel nut, alcohol, and tobacco, respectively. For all tissue assayed, 80.5% of cancerous and 3.2% of grossly normal mucosae were positive for TA. However, neither clinical stage nor TA level in cancerous tissues had a statistical association with the use of individual substances (betel nut, alcohol, and tobacco) or their combined use. CONCLUSION Even though the habitual uses of these substances have been previously reported to be associated with oral cancer incidence, we found a lack of correlation with TA level or with disease severity in our study. These results imply that these consumption habits might only be associated with the early stages of oral cancer development, while the later stages of cancer progression may be more associated with other external factors or dependent on host cellular factors, all of which require confirmation through further investigations.