Case control study on relationship between lung cancer and its susceptibility marker

  Objective   To study the correlation of polymorphisms with CYP1A1, CYP2E1 RsaIand GSTM₁ indepen dently and in corrbination with the risk of lung cancer.

  Methods   Acase control study which included 91 cases of lung cancer and 91 controls collected from the hospital.Blood samples were collected from all cases and controls for detecting CYP1A1, CYP2E1 RsaIand GSTM₁ polymorphisms which were analyzed by PCR and RELP.

  Results   Compared with the m₁m₁ genotype of CYP1A1, ORof the m₂m₂ genotype of CYP1A1 was 1.51(0.76~3.01), OR of the m₁m₂ genoty pe of CYP1A1 was 0.84(0.41~1.72).Compared with the C₁C₂ genotype of CYP2E1, OR of the C₁C₁ genotype of CYP2E1 was 1.80 (0.95-3.40), and those of the C₂C₂ genotype was 5.48(1.21~25.23).Comparing with the GSTM₁(+/+)genotype, OR of the GSTM₁(0/0)was 1.26(0.69-2.30).The results of analysis of the corrbination of two genetic polymerphisms showed that the people of CYP1A1 and GSTM₁ null(0/0)had 2.29(0.92~9.97)who carried out m₂m₂ genotype fold risk of developing lung cancer compared with those who carried out m₁m₁ genotype of CYP1A1 and GSTM₁(+/+)genetype.Compared with GSTM₁(+/+)g enotype with C₁C₂ genotype of CYP2E1, ORof GSTM₁ null(0/0)with C₁C₁ genotype of CYP2E1 was 2.13(0.82~5.56).But there was no statistical significance(P > 0.05).Compared with those carrying m₁m₁ genotype of CYP1A1 and C₁C₂ genotype of CYP2E1, the people with m₂m₂ genotype of CYP1A1 and the C₁C₁ genot ype of CYP2E1 increased in risk of lung cancer, the OR was 3.00(1.03~8.78).The results of analysis of the corrbination of three genetic polymerphisms showed that people carrying m₂m₂ genotype of CYP1A1, C₁C₁ genotype of CYP2E1 and GSTM₁ null (0/0)had higher risk of lung cancer than those with the other genotypes of this three genetic polymerphisms, OR was 3.97 (0.94~16.79).

  Conclusion   Polymorphism of a single gene of CYP1A1, CYP2E1, and GSTM₁ was not associated with the risk of lung cancer.The corrbination of two or more genetic polymerphisms might increase the risk of lung cancer, but there was no statistic significance.The three gene polymorphisms investigated were of minorimportance susceptibility markers for lung cancerin this populat ion.