Chelerythrine chloride Is an isoquinoline alkaloid isolated from the root of Zanthoxylum simulans, Chelidonium majus L., and other Papaveraceae. It has been reported to be a potent and selective inhibitor of PKC (protein kinase C, IC50=0.66 μM), and an independent activator of MAPK pathways. The compound has been observed to induce apoptosis in HL-60 human promyelocytic leukemia cells. The proposed method of action of apoptotic stimulation is through the inhibition of binding BclXL to Bax or Bad at an IC50 = 1.5 μM. When used in combination with cisplatin inhibition of cell proliferation of non-small cell lung cancer cells was increased in an additive/synergistic pattern. Also through inhibition of thromboxane formation and phosphoinositide breakdown chelerythrine chloride was demonstrated to inhibit rabbit platelet aggregation and release. Chelerythrine Chloride is an inhibitor of Cox-2.