2-Methoxyestradiol (2-ME2) is an orally active endogenous metabolite with potent anti-tumor properties. It functions as an anti-angiogenic agent by disrupting endothelial cell function and exerts direct antiproliferative effects on cancer cells through tubulin binding and induction of apoptosis. This small molecule is widely used in oncology research for both in vitro mechanistic studies and in vivo xenograft models.