This meta-analysis indicated that there was no an association between GSTM1-null genotype, GSTT1-null genotype, GSTP1 A/G gene polymorphism and RCC risk in the overall population of Caucasians or Asians.
The GSTM1 and GSTT1 active genotypes in subjects exposed to pesticides (GSTM1: OR = 3.44; 95% CI, 2.04-5.80; GSTT1: OR = 2.84; 95% CI, 1.75-4.60), most of the GSTs genotypes in Asian populations (GSTT1: OR = 2.39, 95% CI = 1.63-3.51; GSTP1: Dominant model: OR = 1.50, 95% CI = 1.14-1.99; Additive model: OR = 1.39, 95% CI = 1.12-1.73; AG vs. AA: OR = 1.47, 95% CI = 1.10-1.97; GG vs. AA: OR = 1.82, 95% CI = 1.07-3.09) and the dual null genotype of GSTT1-GSTP1 (OR = 2.84, 95% CI = 1.75-4.60) showed positive associations with the RCC risk.
The gene-gene interaction in terms of three-way combination of GSTM1 null, GSTT1 null, and GSTP1 (AG/GG) resulted in 4.5-fold increase in RCC risk (OR=4.452; 95% CI=2.220-9.294).
Thus, combining our results with data published previously, it appears that promoter methylation occurs frequently (> or =20% of primary tumours) at CASP8, SLIT2 and RASSF1A in Wilms' tumour and at RASSF1A, TIMP3, DAPK, SLIT2, MT1G and GSTP1 in RCC.
There was also a higher risk of RCC for subjects with the CYP1A1 (m) variant genotype combined with any of the following genotypes: GSTT1 (+) "active" [odds ratio (OR), 2.3; 95% CI, 1.2-4.5], GSTP1 (m) variant (OR, 2.4; 95% CI, 1.0-5.4), or NAT2 (-) "slow acetylator" (OR, 2.5; 95% CI, 1.1-5.5).