Anti-leukaemia effects of leonurine in vitro and in vivo.

The present study was conducted to explore the anti-acute myeloid leukaemia (AML) effects of leonurine. HL-60 and U-937 cells were used to assess the antileukaemia effect of leonurine in vitro, and HL-60 and U-937 xenograft nude mice were used to evaluate its antitumour effect in vivo. Leonurine inhibited the proliferation of HL-60 and U-937 cells in a time- and dose-dependent manner. Moreover, leonurine therapy prevented the growth of tumours in both xenograft animal models. Leonurine could induce apoptosis in HL-60 and U-937 cells. The cytotoxic effects of leonurine on HL-60 and U-937 cells were associated with an increased ratio of Bax/Bcl-2, activation of caspase-3, caspase-8 and caspase-9, and increased expression of cytochrome c in the cytoplasm. Leonurine inhibited activation of the PI3K/Akt pathway in HL-60 and U-937 cells by lowering the phosphorylation levels of PI3K and Akt. Our results indicate that leonurine is a potential anti-AML agent, and this activity may be associated with its repression of the phosphorylation of PI3K and Akt.