Table 2.
Methylation Frequencies in Various Tumor Samples Determined by Either NotI or AscI as a Restriction Enzyme
| Tumor typea | NotI RLGS gels | AscI RLGS gels | Z-test statistic for proportionsb | ||||
|---|---|---|---|---|---|---|---|
| No. of methylated CpG islands | No. of RLGS fragments analyzed | Methylation frequency in NotI gels | No. of methylated CpG islands | No. of RLGS fragments analyzed | Methylation frequency in AscI gels | ||
| Lung | 63 | 1184 | 5.3% | 78 | 1614 | 4.8% | 0.5833 |
| Lung | 59 | 1184 | 5.0% | 62 | 1614 | 3.8% | 1.4669 |
| Lung | 28 | 1184 | 2.4% | 49 | 1690 | 2.9% | −0.8735 |
| Lung | 8 | 1184 | 0.7% | 8 | 1008 | 0.8% | −0.3234 |
| Lung | 7 | 1184 | 0.6% | 13 | 1205 | 1.0% | −1.3079 |
| Lung | 5 | 1184 | 0.3% | 18 | 1734 | 1.0% | −1.8470 |
| Lung | 3 | 1184 | 0.3% | 7 | 1734 | 0.4% | −0.6822 |
| Lung | 1 | 1184 | 0.1% | 3 | 1380 | 0.2% | −0.8503 |
| Lung | 0 | 1184 | 0.0% | 5 | 1614 | 0.3% | −1.9169 |
| MB | 53 | 1702 | 3.1% | 20 | 923 | 2.1% | 1.4091 |
| MB | 32 | 1768 | 1.8% | 22 | 1246 | 1.8% | 0.0903 |
| MB | 31 | 1825 | 1.7% | 21 | 1093 | 1.9% | −0.4401 |
| MB | 32 | 2016 | 1.6% | 19 | 1172 | 1.6% | −0.0735 |
| MB | 15 | 1741 | 0.9% | 19 | 1327 | 1.4% | −1.4947 |
| MB | 14 | 2018 | 0.7% | 9 | 1421 | 0.6% | 0.2140 |
| HNSCC | 13 | 1703 | 0.8% | 14 | 1739 | 0.8% | −0.1387 |
| HNSCC | 3 | 1839 | 0.2% | 6 | 1009 | 0.6% | −1.9625 |
| HNSCC | 0 | 2126 | 0.0% | 1 | 1243 | 0.1% | −1.3080 |
a
HNSCC, head and neck squamous cell carcinomas; MB, medulloblastoma.
b
Z-test static value for testing the significant difference in methylation frequencies in NotI and AscI gels. All of the Z-static values are between −1.96 to +1.96, which suggest that there is no significant (p ≤ 0.05) difference in methylation frequencies in NotI and AscI gels.