Astragalus membranaceus lectin (AML) induces caspase-dependent apoptosis in human leukemia cells

Objectives: Recently, plant lectins have attracted great interest due to their various biological activities such as anti-cancer, anti-fungal and anti-viral activities. We have reported earlier concerning anti-proliferation of human cancer cell lines by a galactose-binding lectin (AML), from a Chinese herb, Astragalus membranaceus. In the present study, detailed investigations into the mechanism of such anti-proliferation properties have been carried out. Results: AML induced apoptosis in a caspase-dependent manner in the chronic myeloid leukemia cell line, K562. Furthermore, we observed that cytotoxicity and apoptosis of K562 cells induced by AML were completely abolished in presence of lactose or galactose. Conclusions: Our results suggest that AML could act as a potential anti-cancer drug.