Table 3.
O6-POB-dGuo levels in (A) esophageal mucosa and (B) oral mucosa. Adduct levels are expressed as mean ± standard deviation (fmol/mg DNA).
| Dosagea | (R)-NNN | (S)-NNN | Rac-NNN | Additiveb | Synergyc | p-valued |
|---|---|---|---|---|---|---|
| A. Esophageal mucosa | ||||||
| Low | 2.4 ±1.0 | 4.5 ±1.7 | 11.2 ±1.6 | 6.9 ±2.0 | 61% | 0.004 |
| Median | 5.5 ±1.2 | 8.5 ±1.3 | 18.4 ±3.3 | 14.0 ±1.7 | 31% | 0.041 |
| High | 14.7 ±3.3 | 16.7 ±4.9 | 26.4 ±10.8 | 31.5 ±5.9 | −16% | 0.469 |
| B. Oral mucosa | ||||||
| Low | 0.8 ±0.3 | 2.2 ±0.7 | 3.5 ±1.0 | 3.0 ±0.8 | 15% | 0.525 |
| Median | 2.0 ±0.6 | 3.3 ±0.6 | 5.2 ±0.1 | 5.3 ±0.8 | −1% | 0.936 |
| High | 3.9 ±1.0 | 5.1 ±0.8 | 8.6 ±1.5 | 9.0 ±1.3 | −4% | 0.744 |
a
Low dosage level: 7 ppm (R)-NNN, 7 ppm (S)-NNN and 14 ppm Rac-NNN; Median dosage level: 14 ppm (R)-NNN, 14 ppm (S)-NNN and 28 ppm Rac-NNN; High dosage level: 28 ppm (R)-NNN, 28 ppm (S)-NNN and 56 ppm Rac-NNN.
b
The additive sum was calculated from the corresponding enantiomers.
c
Synergy was defined by the percentage difference between the racemic NNN group and the additive sum.
d
p-values were calculated for comparison of the adduct level from racemic NNN group and the additive sum of corresponding enantiomers at each dosage level. A p-value less than 0.05 was considered statistically significant.