Purpose: Numerous studies have estimated the association between matrix metalloproteinases (MMPs) polymorphisms and the risk of oral cancer; the results, however, are inconsistent and conflicting. Therefore, we conducted a meta-analysis to evaluate the association of MMP-1, 2, and 3 polymorphisms with oral cancer risk.
Methods: A computerized literature search was conducted of electronic databases and search engines. Odds ratios (OR) and 95% confidence intervals (CI) were calculated for each gene, and the heterogeneity among studies was estimated using the Q-test and I2 values. Overall and subgroup analyses were undertaken. Statistical analyses were conducted using Review Manager v5.3 and Stata v12.0 software.
Results: Eighteen studies were included in this meta-analysis. For MMP-1(-1607) 1G/2G, a significant association was observed using the recessive genetic model (OR = 1.47; 95% CI = 1.14-1.91; I2 = 64%, pheterogeneity = 0.003). In the subgroup studies, a significant association was observed in the Asian subgroup (OR = 1.68; 95% CI = 1.42-1.99; I2 = 17%, pheterogeneity = 0.30 for the recessive model; and OR = 1.59; 95% CI = 1.19-2.13; I2 = 80%, pheterogeneity < 0.00001 for the allelic contrast model) and in the European subgroup (OR = 0.65; 95% CI = 0.44-0.98; I2 = 21%, pheterogeneity = 0.26 for the allelic contrast model). No significant associations were observed with either MMP-2(-1306) C/T or MMP-3(-1171) 5A/6A.
Conclusions: The MMP-1(-1607) 1G/2G polymorphism is associated with oral cancer risk, and the 2G allele played different roles in Asian and European populations.
Keywords: matrix metalloproteinase; meta-analysis; oral cancer; polymorphism.