Since β-lap is also predominantly eliminated via NAD(P)H: quinone oxidoreductase 1 (NQO1) and subsequent UGT catalyzed metabolism [7,22], we assumed that the expression and activity of UGTs in cancer cells could be also an important determinant in the anti-cancer effect of β-lap, similar to that observed from our previous study of Tanshinone IIA. This evidence concerns the gene NQO1 and cancer.