Tangeretin is a methoxyflavone compound found in citrus fruits that demonstrates antiproliferative and antioxidant effects. Tangeretin is described to block cell cycle progression at G1 in MDA-MB-435, MCF-7, and HT-29 cell lines. In human T47D cells, Tangeretin was demonstrated to inhibit ERK1/2 (extracellular-signal-regulated kinases 1/2) phosphorylation. Antioxidant activity is as reported with Tangeretin, and it was demonstrated to suppress induction of COX-2 mRNA by IL-1β and to block IL-1β-induced production of COX-2 in A549 cells.