Table 1.
The dynamic nature of DNA methylation alterations
| DNA methylation marker | Expression level of target gene | Clinical correlation and SLE disease association | Possible mechanisms | Ref. |
|---|---|---|---|---|
| Cytokine methylation biomarkers | ||||
| IL10 and IL1R2 hypomethylation | ↑(white blood cell) | Positively correlated with the SLEDAI score | Increased level of IL-10, decreased level of IL-1 | [105] |
| IL6 hypomethylation | ↑(PBMC) | Positively correlated with renal damage and SLE flare and negatively correlated with serum C3 and C4 | Increased level of IL6 | [67, 107] |
| IFN-related gene biomarker | ||||
| IFI44L hypomethylation | ↑(PBMCs) | Positively correlated with renal damage or disease activity | Increased type I IFN response signature | [110] |
| Specific methylation region marker | ||||
| FOXP3 TSDR methylation | ↑(PBMC) | Positively correlated with the SLEDAI score and disease activity | Decreased level of nTreg cells | [113] |
| Retrovirus gene methylation marker | ||||
| HERV-E and HERV-K hypomethylation | ↑(T cell) | Positively correlated with the SLEDAI score and anti-U1 RNP and anti-Sm antibodies, complementary, lymphopenia | Increased level of HERVs | [114, 115] |