Molecular Epidemiologic Survey To Traffic Police As Occupational High-risk Population Of Lung Cancer Exposed To Traffic Exhaust Gas

Purposes:To study association between traffic exhaust gas and lung cancer and to evaluate signification of molecular marker to screen early lung cancer patient and determinate susceptibility population,correlative molecular markers of lung cancer were detected in occupational population exposed to traffic exhaust gas . Methods:Study object:traffic police of Guangzhou .having three phases in this studyThe first phase:epidemiologic survey to general information and collecting blood sample.The second phase:detecting blood sample,methods and contents:(l)Serum p53 protein expression was measured by enzyme-linked immunosorbent assay (ELISA).(2)Deletion polymorphism of Glutathione S-transferases Ml(GSTMl) gene in peripheral leukocytes was detected by multi-differential Polymerase chain reaction(MD-PCR).(3)The polymorphism of cytochrome P4501A1(CYP1A1) gene in peripheral leukocytes was detected by allele-specific polymerase chain reaction (AS -PCR).The third phase:analysising data:(l)Relationship between the surveyed factors and serum p53 protein expression were evaluated by pearson Chi-Square Tests and logistic regression. (2) Polymorphism distribution of GSTM1 was determinated in the surveyed population by pearson Chi-Square. (3) Relationship between polymorphism of GSTM1 and CYP1A1 and serum p53 protein overexpression was evaluated by pearson Chi-Square. Results:(1)In man,guangdong people,low education degree,small living,smoking,no cooking layer analysis showed that traffic police who work outside of office had been more elevatory trend than the others inside job in expression of serum p53 protein. Furthermore,results also suggested that in traffic police who work outside of office,someone(12.12%) whose length of service was more than 30 years had a significant-4-overexpression of serum p53 protein than the others(5.36%) whose length of service was less than 30 years(P<0.05,OR=2.43,95%CI:1.11-5.33). Overexpression rate of p53 protein is 6.89% in the Group whose exposed hours average every week were more than 40 hours,which was significant higher than the group whose exposed hours were less than 40 hours(P<0.05,OR=1.71,95%CI:1.03-2.81). But by Logistic regression analysis,results didn't show association between overexpression of serum p53 protein and type of work,gender,age,family tumor history,smoking,drinking and diet habit besides native and living. After layering according to type of work,results also didn't appear association between overexpression of serum p53 protein and work hour and exposed hour.(2) Deletion frequency of GSTM1 was 59.12% in the population. No significant association between Deletion and gender,age,living environment,family tumor history,smoking,drinking and diet habit(P>0.05) were found.(3)When relationship between overexpression of serum p53 protein and polymorphism of CYP1A1 and GSTM1 were analysed respectively,no significant difference were found.But combined effect of GSTM1 null and CYPlAlVal/Val increased risk in overexpression of serum p53 protein(P<0.05,OR=3.86,95%CI:0.95-15.59). Conclusions:(l)Expression of serum p53 protein had a elevatory trend in occupational population exposed to traffic exhaust gas. The result suggest that traffic exhaust gas is likely to brought mutation of p53 gene and increased incidence of lung cancer .(2)The population had a relatively high deletion rate in GSTM1 gene.No significant correlation was found between deletion of GSTM1 gene and work environment and smoking .(3)Combined effect of variation of GSTM1 and CYP1A1 increased risk in overexpression of serum p53 protein.