58). Interestingly, as Liu J’s results (Ref. 53) showed increased methylation instability in the TNBC and HER2 BC subtypes, Pham’s work revealed a similar tendency, with the TNBC and luminal B-HER2 subtypes exhibiting a significant proportion of hypermethylation (Ref. 58). Moreover, four regions of DMR covering the SOX17, RASSF1 and OTX2 genes with significant hypermethylation rates distinguished BC patients from healthy individuals (Ref. 58). This evidence concerns the gene ERBB2 and breast cancer.