4-Methoxyestrone

**Semantic type:** Organic Chemical

**Definition:** A metabolite formed during the methylation of 4-hydroxyestrone (4-OHE1) by catechol-O-methyltransferase (COMT) and devoid of any oncogenic or anticarcinogenic activities. The 4-methoxyestrone (4-MeOE1):4-OHE1 ratio can be used to assess methylation efficiency and cancer risk. Lower 4-MeOE1:4-OHE1 ratios suggest inadequate methylation and increased risk of certain cancers.

**Synonyms:** - 4-MeE1 - 4-MeOE1 - 4-OMeE1