Interestingly, some studies have shown that Jag1 promoter is hypomethylated in breast cancer cells.44 Also, Jag1 promoter has been found to be a target of histone demethylase KDM4C.45 Thus, additional studies are necessary to elucidate whether the aforementioned epigenetic modifications may also regulate Jag1 expression in human ICCs. This evidence concerns the gene KDM4C and breast carcinoma.