Taken together, these findings suggest that Chilean people carrying single or combined GSTM1 and CYP1A1 polymorphisms could be more susceptible to lung cancer induced by environmental pollutants such as polycyclic aromatic hydrocarbons.
Therefore, in 46 published studies in Chinese populations, we found evidence of an association between the CYP1A1 variant and GSTM1 null genotypes and increased risk of lung cancer.
Several polymorphisms within the CYP1A1 locus have been identified and have been shown to be associated with lung cancer risk, particularly in Asian populations.
Cytochrome P450 1A1 (CYP1A1) activity is associated with increased susceptibility to lung cancer induced by polycyclic aromatic hydrocarbons such as benzo[a]pyrene (BP).
Our observations do not support the view that the presence of the M2 allele at the MspI site of the CYP1A1 gene constitutes a significant lung cancer risk in Caucasians.
Three examples of pharmacogenetic risk factors are discussed: the first two are p450 enzymes whose activity has been associated with susceptibility to lung cancer (debrisoquine hydroxylase, aryl hydrocarbon hydroxylase), and the last, N-acetyltransferase, a non-p450 enzyme, has been associated with bladder cancer susceptibility.
This meta-analysis suggests that the MspI and exon 7 polymorphisms of CYP1A1 correlate with increased lung cancer susceptibility and there is an interaction between two genotypes of CYP1A1 polymorphism and smoking, but these associations vary in different ethnic populations, histological types of lung cancer and gender of case and control population.
We investigated if the individual and/or combined modifying effects of the CYP1A1 MspI T6235C, GSTM1 present/null, GSTT1 present/null and GSTP1 Ile105Val polymorphisms are related to the risk of developing lung cancer in relation to tobacco consumption and occupation in Asturias, Northern Spain.
The present data suggest that the CYP1A1 exon 7 polymorphism may confer an increased risk of lung cancer, particularly of SCC, and especially in never-smokers and in women.
We conducted a case-control study of 218 northern Indian lung cancer patients along with 238 healthy controls, to assess any association between CYP1A1, GSTM1 and GSTT1 polymorphisms, either separately or in combination, with the likelihood of development of Lung cancer in our population.
Human CYP1A1 (cytochrome P(1)450) gene: lack of association between the Msp I restriction fragment length polymorphism and incidence of lung cancer in a Norwegian population.
Overall, a significant association between lung cancer and the variants of CYP1A1 MspI was found among smokers (type B and type C combined vs. type A: OR = 1.89, 95% CI = 1.15-3.11, P = 0.000 for heterogeneity), whereas not found among non-smokers.
This meta-analysis suggests that the exon7 polymorphisms of CYP1A1 correlate with increased lung cancer susceptibility and there is an interaction between CYP1A1 exon7 polymorphisms and smoking, but these associations vary in different genders of the case and control populations.
Present studies on increased risk of smoking-related lung cancer associated with phenotypic or genotypic variation of the genes encoding for CYP1A1 or CYP2D6 enzymes are summarized.
In Caucasians, those with the IIe/Val genotype at CYP1A1Ile(462)Val locus were at decreased risk of having lung cancer compared to those with the lle/lle genotype, after adjusting for age at diagnosis, sex, pack years of smoking and family history of cancer (OR=0.41 95% Cl 0.19-0.90).
The apparent lack of association of CypIA1 MspI polymorphism with lung cancer in this area reported in our previous study and the results of the present study indicate that the "true" responsible site for lung cancer susceptibility should be the Ile-Val polymorphism in the catalytic site of CypIA1.
Particular alleles of CYP1A1, such as CYP1A1I462V have been correlated with a higher incidence of breast and lung cancer, but it is unknown whether these variants express enzymes in vivo that are more potent in generating genotoxins.
The risk of lung cancer was increased with the combination of CYP1A1*2B or CYP1A1*4 alleles and the double deletion of both GSTM1 and GSTT1 up to an odds ratio (OR) of 8.25 (95% confidence interval 2.29-29.77) for the combination including CYP1A1*4; among never smokers, the latter combination was associated with an OR of 16.19 (1.90-137).
A pertinent combination of multiple "at-risk" genotypes of CYP1A1rs4646903, the GSTM1 deletion polymorphism and ERCC2 rs13181 was at a 5.94-fold (95% CI = 2.77-12.7) increased risk of lung cancer.
The polymorphic frequency of 10 genetic susceptibility genes and their association with lung cancer were examined in a northern Thai population: CYP1A1 (MspI), CYP1A1 (Ile462Val), CYP2E1 (PstI), CYP2E1 (DraI), GSTM1, GSTT1, MPO (AciI), OGG1 (Ser326Cys), TP53 (Arg72Pro), and MMP1(AluI).