SAE1 and breast cancer: A case in point is the SUMO1 activating enzyme subunit 1 (SAE1), a SUMOylation enzyme; levels of DNA methylation at the SAE1 gene site (cg14042711) are negatively correlated with levels of SAE1 expression and global SUMOylation, indicating the regulatory role of methylation in SUMOylation in breast cancer [149].