5-Methylcytosine immunohistochemistry for predicting cutaneous melanoma prognosis.

There is a correlation between DNA methylation and the diseased stage and poor survival. 5-methylcytosine (5-mC) is one of the epigenetic modifications of bases that researchers focus on. Staining with 5-mC immunohistochemistry was used to examine pathological samples taken from individuals diagnosed with cutaneous melanoma. Between Breslow levels 2 and 4, there was a significant difference in the H-score of 5-mC expression (p = 0.046). A significant reduction in 5-mC expression H-scores was seen in patients who were diagnosed with ulcers (p = 0.039). It was shown that patients with low 5-mC had a significantly worse overall survival rate (p = 0.027).

Alu repetitive sequence CpG methylation changes in burn scars.

Alu elements are retrotransposons related to epigenetic modifications. To date, the role of epigenetics in hypertrophic scars from burn remains unknown. Here, our aim was to examine the pathophysiology of hypertrophic scars from an epigenetic perspective. For that, we performed a cross-sectional analytical study using tissue and blood samples from burned and healthy patients (n = 23 each) to detect Alu methylation levels and patterns. The results of the combined bisulfite restriction analysis technique were categorized into four groups based on the methylation status at the CpG dinucleotides from the 5' to the 3' ends of the Alu sequence: hypermethylated (mCmC), hypomethylated (uCuC), and partially methylated (uCmC and mCuC). Alu methylation levels were significantly lower in hypertrophic scar tissues than in normal skin (29.37 ± 2.49% vs. 35.56 ± 3.18%, p = 0.0002). In contrast, the levels were significantly higher in white blood cells from blood samples of burned patients than in those of control blood samples (26.92 ± 4.04% vs. 24.58 ± 3.34%, p = 0.0278). Alu total methylation (mC) and the uCmC pattern were significantly lower, whereas uCuC was significantly higher, in hypertrophic scar tissues than in normal skin (p < 0.0001). Receiver operating characteristic analysis indicated that the uCmC and uCuC patterns are useful as hypertrophic scar DNA methylation markers after burn, with 91.30% sensitivity and 96.23% specificity and 100% sensitivity and 94.23% specificity, respectively. Our findings suggest that epigenetic modifications play a major role in hypertrophic scar pathogenesis, and may be the starting point for developing a novel technique for burn scar treatment.