A naturally occurring plant flavone that displays remarkable anti-inflammatory, antioxidant and anti-carcinogenic properties. It selectively inhibits casein kinase II (CK2). Apigenin inhibits CK2 activity in the renal cortex with an IC₅₀ value of 30 µM to improve renal function in a rat model of glomerulonephritis. CK2 inhibition by 20 µM apigenin decreases the degradation of IκBα and down-regulates NF-κB levels in WEHI 231 cells. At 5 µM, it is a potent inhibitor of the synthesis of the inflammatory mediators nitric oxide and prostaglandin E2, reducing inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression by 56% and 64%, respectively, in the macrophage cell line J774A.1.