Table 1.

Association between expression of AhR and CYP1B1 or CYP1A1 in lung adenocarcinoma stratified by smoking history

AhRCYP1B1 expression
CYP1A1 expression
LowHighP*NegativePositiveP*
Total (n = 107)Low3919<0.00143150.009
High16332425
Smokers (n = 30)Low950.0241310.002
High313610
Nonsmokers (n = 73)Low28140.03129130.459
High12191813
  • NOTE: AhR, CYP1B1, and CYP1A1 proteins were detected with immunohistochemical methods. Expression levels were calculated as of cases showing cells with cytoplasmic immunostaining scored according to staining intensity. For AhR immunohistochemistry, the specimen was scored as a high expresser when >10% of the adenocarcinoma cells exhibited cytoplasmic staining intensities that were equal to those of the prostate (positive control, Fig. 1A). For CYP1B1 immunohistochemistry, the specimen was scored as a high expresser when >10% of the adenocarcinoma cells exhibited cytoplasmic staining intensities that were equal to those of adjacent bronchiolar walls (bronchiolar wall, Fig. 1D). For CYP1A1 immunohistochemistry, the specimen was considered to be CYP1A1 positive when >10% of the adenocarcinoma cells exhibited cytoplasmic staining intensities that were stronger than those of the adjacent stroma (Fig. 1C). Four cases were missing a smoking history.

  • * P < 0.05, Fisher's exact test.