The association between glutathione S-transferase M1 (GSTM1) and glutathione S-transferase T1 (GSTT1) null polymorphisms and oral cancer is not consistent across studies, and data on their interaction with smoking in oral cancer are lacking. The authors systematically searched PubMed and SciVerse Scopus for case-control studies examining the association between null genotypes of the GSTM1 and GSTT1 genes and oral cancer. Twenty-eight case-control studies published in English were identified. Summary odds ratios were derived via random-effects models. The summary odds ratio for the GSTM1 null genotype was 1.43 in Asians (95% confidence interval (CI): 1.14, 1.78; P < 0.01, I (2) = 73%) and 0.98 in Caucasians (95% CI: 0.76, 1.28; P = 0.91, I (2) = 0%). Case-only analysis of 6 studies (552 cases) showed an inverse multiplicative interaction between GSTM1 null polymorphisms and smoking (ever/high levels of smoking vs. never/low levels) (odds ratio (OR) = 0.51, 95% CI: 0.32, 0.82; P = 0.01, I (2) = 34%). The GSTT1 null genotype was not significantly associated with oral cancer in Asians (OR = 1.07, 95% CI: 0.82, 1.38; P = 0.63, I (2) = 65%) or Caucasians (OR = 1.04, 95% CI: 0.41, 2.65; P = 0.93, I (2) = 55%). In conclusion, the GSTM1 null genotype may be associated with a higher risk of oral cancer in Asians but not in Caucasians, and this effect may be modified by smoking status. The GSTT1 null genotype may not be associated with oral cancer.
[1]Shanghai Jiao Tong Univ, Dept Epidemiol, Sch Publ Hlth, Shanghai 200030, Peoples R China.
[2]Rosetta Inpharmat, Res Genet, Seattle, WA USA.
[3]Shanghai Jiao Tong Univ, Dept Prevent Med, Sch Publ Hlth, Shanghai 200030, Peoples R China.
[4]Fudan Univ, Dept Epidemiol, Sch Publ Hlth, Shanghai 200433, Peoples R China.
[5]Karolinska Inst, Dept Publ Hlth Sci, Stockholm, Sweden.
[6]Harvard Univ, Brigham & Womens Hosp, Div Prevent Med, Sch Med, Boston, MA 02115 USA.
[7]Univ Florida, Dept Epidemiol & Biostat, Coll Publ Hlth & Hlth Profess, Gainesville, FL USA.
(8.0+极速模式)