Differential Control of Growth, Apoptotic Activity, and Gene Expression in Human Breast Cancer Cells by Extracts Derived from Medicinal Herbs Zingiber officinale
Ginger extract induces apoptotic cell death in MCF-7 and MDA-MB-231 cells. (a) Microphotographs showing the inhibitory effect of gingerextract on cellular growth of MCF-7 and MDA-MB-231 cells. Cells were plated onto 6-well plates and treated with indicated concentrations of ginger for 24 h. The photographs were taken directly from culture plates using a phase microscope. Note cell shrinkage, irregularity, and detachment in ginger-treated cultures. Representative pictures are shown from three independent experiments. (b) DAPI staining for MCF-7 and MDA-MB-231 cultures treated with ginger extract for 24 h. Note apoptotic cells with condensed chromatin () and fragmented nuclei () were clearly visible in ginger-treated, but not in control-treated, cultures. Histogram panels show quantitation of apoptotic cells with condensed chromatin in ginger-extract treated-MCF-7 and MDA-MB-231 cultures. Columns, mean of six to nine determinations. (c) The ginger extract treatment induced DNA fragmentation in MCF-7 and MDA-MB-231 cells. Cells were incubated with indicated concentrations of ginger extract for 24 h. Genomic DNA was isolated and electrophoresed in 1% agarose gel. M: 100 bp DNA ladder marker. (d) The ginger extract treatment increased the cleavage of caspase-3 (upper panel) and PARP (middle panels) in MCF-7 and MDA-MB-231 cells. Cells were treated with indicated concentrations of ginger extract for 24 h; thereafter, cell lysates were prepared and analyze by Western blot as detailed in Section 2, for detecting the cleavage of caspase-3 and PARP using. Equal loading of samples was confirmed by -actin (lower panels); representative blots are shown from three independent experiments with almost identical observations.