Table III.
Analysis of transcriptional markers of UV-induced oxidative stress
| Univariate analysis | ||||
|---|---|---|---|---|
| Variable | Patients* | ΔCT#Gclm (mean, ±SD) | Analysis of Covariance | |
| Control | UV-irradiated | Expression ratio∥ (95% CI), P value | ||
| Treatment | ||||
| Placebo | 50 (51%) | 9.74 ±0.69 | 9.14 ±0.75┼ | 1.00 |
| Drug | 49 (49%) | 9.42 ±0.98 | 8.99 ±0.83 | 0.97 (0.82 – 1.16), 0.76 |
| MC1R status | ||||
| Low-risk | 49 (49%) | 1.00 | ||
| High-risk | 50 (51%) | 1.07 (0.88 – 1.30), 0.52 | ||
| ΔCT Slc1A4 (mean, ±SD) | ||||
| Control | UV-irradiated | |||
| Treatment | ||||
| Placebo | 50 (51%) | 9.21 ±0.83 | 9.40 ±1.06╪ | 1.00 |
| Drug | 49 (49%) | 9.28 ±0.89 | 9.29 ±0.87 | 1.06 (0.84–1.34), 0.63 |
| MC1R status | ||||
| Low-risk | 49 (49%) | 1.00 | ||
| High-risk | 50 (51%) | 1.04 (0.83–1.31), 0.73 | ||
| ΔCT Slc7A11 (mean, ±SD) | ||||
| Control | UV-irradiated | |||
| Treatment | ||||
| Placebo | 50 (51%) | 8.97 ±1.04 | 9.03 ±0.95╫ | 1.00 |
| Drug | 49 (49%) | 8.62 ±0.96 | 8.73 ±1.13 | 1.16 (0.90 – 1.49), 0.27 |
| MC1R status | ||||
| Low-risk | 49 (49%) | 1.00 | ||
| High-risk | 50 (51%) | 1.11 (0.87–1.43), 0.40 | ||
One subject with low-risk MC1R randomized to drug was excluded from the analyses because the lesions removed were seborrheic keratoses and not nevi.
ΔCT is the difference in CT between the gene of interest and RPLP0.
Analysis of covariance was used to examine the relationship between individual categorical variables and the change in ΔCT, with categorical variable and ΔCT in the un-irradiated nevus as predictors and ΔCT in the irradiated nevus as response. Additional analyses of age, gender, height, weight, hair color, and eye color as covariates did not reveal any significant predictors (not shown). The expression ratio is estimated as 2−ΔCT.
For placebo group, difference between control and UV-irradiated was significant (P<0.001, Wilcoxon test).
For placebo group, difference between control and UV-irradiated was not significant (P=0.012, Wilcoxon test).
For placebo group, difference between control and UV-irradiated was not significant (P=0.062, Wilcoxon test).
We tested for potential interaction between treatment and MC1R status for each analysis, and did not find significance for any of them (not shown).