Impact of the deletion glutathione S-transferase (class Mu) on lung cancer risk among smokers

Abstract

Background The results of several studies assessing the effect of the glutathione S-transferase class Mu 1 (GSTM1) null variant on the genetic susceptibility of tobacco-related cancers have been conflicting. In this work, we aim to identify the impact of the deletion of GSTM1 on lung cancer risk among smokers. Methods This study was conducted on 20 patients diagnosed with primary lung cancer and 20 healthy individuals as a control group. They were subject to full medical history taking, complete clinical examination, and GSTM1 genotyping by PCR. Results Both studied groups were matched for age, sex, and smoking status. No statistically significant difference was exhibited between the frequency of GSTM1 positive and GSTM1 null in the studied population. No risk of lung cancer associated with GSTM1 null genotype was demonstrated between the patients and control group (n = 14/20 cases) (p = 0.110, OR = 2.852, 95% CI 0.777–10.467). Additionally, there was no association between the risk of lung cancer and the presence of the gene either in smokers (p = 1, OR = 1.8 and 95% CI 0.124–26.196) or non-smokers; (p = 0.063, OR = 4.4 and 95% CI 0.889–21.78). No statistically significant risk was found between the frequencies of GSTM1 null and the various histopathological types of lung malignancy. Conclusion The results of this work demonstrated no association between the occurrence of the GSTM1 null variant, even when stratified for smoking status, and the risk of lung cancer.