Although no significant links were found between GST polymorphism and treatment response, null genotypes of GSTM1, GSTT1 and 'G' allele of GSTP1 bring a higher risk of severe gastrointestinal toxicity due to chemoradiation therapy in cervical cancer.
For the GSTT1 polymorphism, the null genotype of GSTT1 was not statistically significantly associated with CC risk in total population (OR=1.36, 95% CI=0.97-1.90).
These results suggest that GSTT1 null genotype may increase the risk of cervical cancer particularly in the cases with high-risk HPV types in a Japanese population.
GSTM1 null, GSTT1 null, and GSTM3*AB genotypes may confer higher susceptibility to cervical cancer and cancer risk because at-risk genotypes are additive.
This study evaluates the combined effects of genetic polymorphisms of GSTM1, GSTT1, and GSTP1 on susceptibility to cervical cancer and interaction of these genes with smoking.
In this study, genetic polymorphisms, NQO1 C609T, GSTM1 positive/null, and GSTT1 positive/null, were examined with reference to cervical cancer risk in a population-based incident case-control study in Japanese.
Although the GSTM1 and GSTT1 genotype was not significantly associated with cervical cancer development for all women, the GSTM1 null genotype was significantly associated with an increased risk of cervical cancer development in women with high-risk HPV infection (OR = 2.9, 95% CI: 1.0-8.2).
Further, the combined analysis of both GSTM1 null and GSTT1 null genotypes did not appear to influence the susceptibility to cervical cancer, suggesting that polymorphisms of other detoxifying enzymes may play a significant role in cervical carcinogenesis.