Genetic Polymorphism Of Glutathione S-transferase P1 Gene And Susceptibility To Lung Cancer

Objective: To analyse the relationship between the GSTP1 genotypes and susceptibility to lung cancer, and explore the sensitive genotype of lung neoplasm through evaluating on the intens ion of the association between GSTP1 gene and lung cancer; To provide basis for screen and diagnosis of lung cancer. Methods: Adopted the molecular epidemiological studies.A case-control study was carried out, with 158 cases and 168 controls; Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was taken to analyse the GSTP1 genotypes and identify the gene frequencies. -5- Results: l.The proportion of AA, AG and GG genotypes were 56.3%, 37. 4% and 6. 3% respectively among 158 cases, while the ratio were 58. 3%, 34. 6% and 7. 1% respectively among 168 controls. The difference of GSTP1 genotypes distribution were not statistically significant between cases and controls ( x 2=0. 32, P=0. 853) 2. Through comparison of GSTP1 gene frequencies according the histological type, the difference were not significant: squamous cell carcinoma versus controls: x 20 06, P0. 971; adenocarcinoma versus controls: x21.00, P0.971; others histological types carcinoma versus controls: x20. 83, P0.662. 3. The differences was not statistically significant between the cases and the controls on GSTP1 genotypes after stratified by smoking index (SI): STh0, x2=0.22, P0. 898; S1<40, x2=0.95, P0.621; I≥40, x2=2.76, P=0.251. 4. After excluding the confounding of smoking in the elder age subgroup (age 50 years or elder), the frequencies of GSTP1 variant genotypes (AGorGG) in the cases weres evidently higher than that in the controls ( x 28 82, Fisher's exact test P=0. 005, OR=9. 30, 95%CI:1. 78-48. 50) 5.The results of multiple logistic regression analysis -6- showed that the risk to lung cancer among smokers was three times as high as nonsmokers (0R3. 184, 95%CI:1.5734-6.2601) .After balanced other possible risk factors related to lung cancer, such as sex, age, smoking and poison history, the result was not evidently support the view that the variant GSTP1 genotypes played an important role (P=0. 6357) and interacted to lung cancer with smoking (P=0. 7847) Conclusions: The frequencies of individuals carrying homozygous of the GSTP1 variant allele were 6. 7% among the Han nationality in Guangdong Province. In the elder age subgroup (age 50 years or elder), the risk to lung cancer was 8. 3 times higher among the males carryingGalleles(AGandGG) than those carrying A alleles (AA) with the exception of smoking.