Background and purpose: Previous studies showed activated aryl hydrocarbon receptor (AhR) might be involved in the development of breast cancer induced by polycyclic aromatic hydrocarbons (PHAs) and AhR which was regarded as transcription factors activated by ligand could induced many enzymes expression. Therefore

this study aimed to explore the protein level of AhR and aryl hydrocarbon metabolic enzymes in vivo with a relationship of the breast cancer and pathology indicators. Methods: A case-control study was 1∶1 matched and 65 pairs blood samples were collected

the ELISA was used in testing blood protein levels of the aromatic hydrocarbon receptor and aryl hydrocarbon metabolic enzymes. Meanwhile pathological data was collected. The Rank sum test statistical analysis was used in analyzing measurement data

Spearman test was used in correlation analysis. Results: Statistical analysis revealed that there was no statistical difference in aldehyde dehydrogenase(ALDH)

cytochrome P450(CYP450) between the case group and the control group (Z=0.196

P=0.845;Z=0.269

P=0.788);and the AhR

NQO1

GST control group concentrations were lower than that in the case group. There were statistical differences of AhR

quinone oxido-ereductase 1(NQO1)

glutatnione-S-transferases(GST) between the control group and the case group(Z=1.956

P=0.041; Z=2.627

P=0.009; Z=3.272

P=0.001). Correlation analysis showed that AhR has a higher correlation in case group with GST

NQO1 (r=0.665

P0.01; r=0.704

P0.01). Grouping with the pathology indicators (ER

PR

HER-2) -

+

++

+++

found that the level of grouping by ER

AhR protein levels and GST protein levels have a discrepancies(P0.05). Conclusion: These results might suggest that the protein levels of AhR and aryl hydrocarbon metabolic enzymes have a significant impact on breast cancer. Detection of enzyme protein levels may be helpful for early detection of breast cancer

prompt treatment options and prognosis are meaningful.