Isocorydine is an aporphine alkaloid that has been found in A. squamosa that has vasodilatory and anticancer activities. It reduces the action potential duration and increases the effective refractory period in isolated canine Purkinje fibers when used at a concentration of 30 μM. Isocorydine induces relaxation of norepinephrine-precontracted isolated rabbit aortic strips with an EC50 value of 12.6 μM. It is cytotoxic to A549 lung cancer cells (IC50 = 197.7 μM), as well as Huh7, HepG2, SNU-449, and SNU-387 hepatic cancer cells (IC50s = 161.3, 148, 262.2, and 254.1 μg/ml, respectively). Isocorydine, in combination with doxorubicin, reduces tumor growth in a Huh7 mouse xenograft model.