Cancer letters
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We recently demonstrated that two chalcones isolated from Angelica keiskei roots have anti-tumor and anti-metastatic activities through the inhibition of tumor-induced angiogenesis, but the anti-tumor substances of Angelica japonica roots are unknown. We attempted to clarify the anti-tumor action and its mechanisms of a major component 3'-O-acetylhamaudol isolated from A. japonica roots. ⋯ Furthermore, we examined the effects of 3'-O-acetylhamaudol on angiogenic factors (vascular endothelial growth factor receptor-2 (VEGFR-2) phosphorylation in human umbilical vein endothelial cells (HUVECs), and vascular endothelial growth factor (VEGF) production and hypoxia-inducible factor (HIF)-1alpha expression in tumors). 3'-O-Acetylhamaudol (25 and 50 mg/kg, twice daily) inhibited the tumor growth in colon 26-bearing mice. Although 3'-O-acetylhamudol had no effect on the VEGF production and HIF-1alpha in colon 26 cells, it (10 microM) inhibited the VEGF-induced angiogenesis and VEGF-induced VEGFR-2 phosphorylation in HUVECs. 3'-O-Acetylhamaudol has anti-tumor effects mediated through dual mechanisms, i.e., anti-angiogenic actions and the modulation of the immune system in the spleen and small intestine in tumor-bearing mice.
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Viscum album (Mistletoe) is one of the most widely used alternative cancer therapies. Aqueous mistletoe extracts (MT) contain the three mistletoe lectins I, II and III as one predominant group of biologically active agents. Although MT is widely used, there is a lack of scientifically sound preclinical and clinical data. ⋯ DNA-fragmentation assays indicated that dose-dependent induction of apoptosis was the main mechanism of cell death. Finally, we evaluated the efficacy of MT-A and MT-P in an in vivo SCID-model of pre-B ALL (NALM-6). Both MTs significantly improved survival (up to 55.4 days) at all tested concentrations in contrast to controls (34.6 days) without side effects.