Induction of mitochondrial dependent apoptosis and cell cycle arrest in human promyelocytic leukemia HL-60 cells by an extract from Dorstenia psilurus: a spice from Cameroon

Background: The use of edible plants is an integral part of dietary behavior in the West region of Cameroon. Dorstenia psilurus (Moraceae) is widely used as spice and as medicinal plant for the treatment of several diseases in Cameroon. The aim of this study is to investigate the cytotoxic and apoptotic potential of methanol extract of D. psilurus in human promyelocytic leukemia (HL-60) cells and prostate cancer (PC-3) cells. Methods: Cytotoxicity of D. psilurus extract was tested in HL-60 and PC-3 cells using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) reduction assay and flow cytometric methods Results: The methanol extract of D. psilurus have significant in vitro cytotoxic activity in HL-60 cells and PC-3 cells with IC50 value of 12 +/- 1.54 mu g/ml and 18 +/- 0.45 mu g/ml respectively after 48 h. The mechanism of antiproliferative activity showed that after 24 h, D. psilurus extract induces apoptosis on HL-60 cells by the generation of reactive oxygen species (ROS) along with concurrent loss of mitochondrial membrane potential, modification in the DNA distribution and enhance of G2/M phase cell cycle. Conclusion: The extract induces apoptosis of HL-60 cells associated with ROS production, loss of mitochondrial membrane potential and apoptotic DNA fragmentation.