Luteolin was reported to show degranulation inhibitory activities in antigen-stimulated rat basophil leukemia RBL-2H3 cells (IC50 5.8 μM) [42], and suppressed Substance P (SP) or IgE/anti-IgE–stimulated β-Hex, histamine and TNF-α release from LAD2 mast cells [28]. Here, TAC1 is linked to leukemia.