Abstract:

OBJECTIVE: To explore environmental factors and the association of NAT2 genetic polymorphism and female breast cancer，and their interactions. METHODS：A case-control study was adopted to collect information in 140 female primary breast cancer diagnosed by pathology and treated in major hospitals of Tangshan city. The 140 controls were selected from the female patients without tumor from the same hospitals at the same time. Each subject was investigated by an unified questionnaire，which mainly included eating habits and ways of life，environment and occupational exposure，etc. DNA was extracted by salting out method，and NAT2 genotype were detected by polymerase chain reaction-restriction fragment polymorphism (PCR-RFLP). SPSS 13.0 were adopted to statistically analyze the data. RESULTS：Environmental risk factors of female breast cancer were environmental PAHs pollution of residence，occupational exposure to PAHs，occupational use of pesticide exceeding 10 years，indoor insecticide use over 5 years，passive smoking wore than 10 years. While more intake of beans，fumes exhaust equipment used in cooking were all protective factors. The frequencies of rapid and slow speed acetylation phenotypes were 55.0%，45.0% in case group，and 77.9%，22.1% in control group，respectively. The difference was statistically significant (P<0.05). There were interactions between passive smoking exceeding 10 years，as well as occupational PAHs exposure and NAT2 slow speed acetylation phenotype. The interaction value were 3.39 and 1.70，respectively (P<0.05). CONCLUSION： There were interactions between passive smoking or occupational exposure and carrying slow speed acetylation phenotype，which would increase the risk of breast cancer.

Key words: breast cancer, environmental factors, N-acetyltransferase-2, genetic polymorphisms, interaction