Table 2 Summary DNA methylation level of candidate genes in training and testing sets

Normal

3.8 ± (3.5–4.0)

2.0 ± (1.8–2.7)

5.8 ± (5.3–6.5)

2.3 ± (1.6–2.9)

7.6 ± (6.8–8.1)

OC

2.7 ± (1.8–3.2)***

1.0 ± (0.3–1.5)* **

4.4 ± (3.8–5.7)*

0.1 ± (−0.1 − 1.9)***

5.1 ± (4.2–6.2)***

Normal

3.6 ± (3.0–4.1)^a

2.8 ± (2.0–3.5)

–

4.2 ± (3.2–5.3)

7.6 ± (6.7–8.0)

OC

2.0 ± (1.1–3.1)***

0.9 ± (0.2–2.0)* **

–

0.4 ± (− 0.0 − 1.9)***

4.9 ± (3.7–6.3)***