Methods: A total of 224 patients with oral cancer and 239 healthy controls were recruited into the present study. A standardized questionnaire was applied to collect the demographic data and histories of substances' usage. We collected 10ml peripheral blood for DNA isolation. The polymorphisms in MMP-13 -77A>G and TIMP-1 +372T>C genes were genotyped by Taqman probe real-time PCR method.
Results: The prevalence of smokers, drinkers, and betel-quid chewers were significantly higher in oral cancerous patients than those in healthy controls. Polymorphisms in MMP-13 -77A>G and TIMP-1 +372T>C genes were not associated with oral cancer development. Stratification analysis and multivariate logistic regression analysis showed that the effect size between betel quid chewing and oral cancer risk could be differentiated by the MMP-13 -77A>G polymorphisms. An increase trend of betel chewing to OSCC risk was also found in participants with GG, AG, and AA genotypes. Since the TIMP-1 gene is located on the X chromosome, stratification analysis and multivariate logistic regression analysis indicated that the association between substances' usage and oral cancer risk were not significantly differentiated by the TIMP-1 +372T>C polymorphisms.
Conclusions: We suggest that the polymorphisms in MMP-13 -77A>G and TIMP-1 +372T>C genes were not associated with oral cancer development. The association between substances' usage and oral cancer risk could be differentiated by the MMP-13 -77A>G polymorphisms but no such relationship was found in participant with different TIMP-1 +372T>C polymorphisms.