Activity of crude extract of Rubus crataegifolius roots as a potent apoptosis inducer and DNA topoisomesase I inhibitor

The effects of methanol extract of Rubus crategifolius roots and its solven t fractions were investigated on the proliferation of MCF-7 human breast ca rcinoma cells. The methanol extract inhibited the proliferation of MCF-7 ce lls in a concentration dependent manner. Moreover, their methanol soluble ( W-M) fraction had the greatest inhibitory effect on the growth of MCF-7 cel ls. To evaluate whether the W-M fraction affects on the cell cycle of MCF-7 cells, cells treated with this fraction were analyzed with flow cytometry. The W-M fraction increased G(0)/G(1) phase after 24 h-treatment and induce d apoptosis after 48 h-treatment. The hallmark of apoptosis, DNA fragmentat ion, also appeared by W-M fraction after 48 h-treatment. Furthermore, the m ethanol extract and its W-M fraction inhibited the activity of the topoisom erase I enzyme in the relaxation assay. From these results, their W-M fract ion as well as methanol extract of R. crategifolius roots are necessary for further studies as a potent inhibitor of the growth of cancer cells.