Table I.
Aberrant methylation levels of genes tested and cut-off values obtained from ROC curves.
| Genes | Cut-off value | Tumor tissue | Matched non-malignant lung tissue | P-valueb | P-valuec | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
|
|
||||||||||
| Median | Mean ± SD | Range | Methylation (%)a | Median | Mean ± SD | Range | Methylation (%)a | ||||
| LINE-1 | 71.2 | 71.0 | 67.9±10.0 | 35.0–80.4 | 31 (55) | 73.4 | 73.8±2.9 | 68.0–86.5 | 9 (16) | <0.0001 | <0.0001 |
| SLIT2 | 8.38 | 11.0 | 12.3±7.6 | 3.4–42.6 | 36 (64) | 6.1 | 6.6±2.0 | 3.4–11.8 | 8 (14) | <0.0001 | <0.0001 |
| MAL | 2.25 | 2.0 | 2.5±1.6 | 1.0–8.2 | 26 (46) | 1.8 | 1.8±0.3 | 1.0–2.6 | 4 (7) | 0.0010 | <0.0001 |
| IGFBP7 | 6.38 | 6.6 | 7.9±4.2 | 2.1–19.1 | 30 (54) | 4.9 | 5.1±1.0 | 3.4–9.3 | 3 (5) | <0.0001 | <0.0001 |
a
Number and percentage of aberrant methylation determined by cut-off value.
b
P-value obtained from paired t-test by comparing the methylation levels between tumors and matched non-malignant lung tissues.
c
P-value obtained from Fisher’s exact probability test by comparing the frequencies of aberrant methylation.