Figure 1.

Sulforaphane (SF) increases drug-mediated effects on cell viability, clonogenicity and induction of apoptosis in pancreatic cancer stem cells (CSCs). (a) CSC^high pancreatic cancer cells were left untreated (CO), or were treated with SF (5 µmol/l), cisplatin (CIS), gemcitabine (GEM), doxorubicin (DOX) or 5-flurouracil (5-FU) in concentrations indicated alone or in combination with SF as indicated. Seventy-two hours later viability was determined by MTT assay (upper panel). Data are presented as mean ± SD (*P < 0.05 compared with treatment in the absence of SF). Representative pictures of cells were taken at ×100 magnification (lower panel). (b) To examine clonogenic cell division, CSC^high pancreatic cancer cells were seeded in 6-well tissue culture plates and treated with SF (5 µmol/l) and GEM (5 nmol/l) alone or in combination (SF+GEM). Seventy-two hours later cells were trypsinized and re-plated at low density in 6-well plates. Ten days later colonies containing >50 cells were counted under a dissecting Zeiss Stemi DV4 microscope. Data are presented as mean ± SD. Photographs of the fixed and stained colonies are presented on the left panel. (c) MIA-PaCa2 cells were seeded in 6-well tissue culture plates and treated similar to the previous MTT assay. Induction of apoptosis was evaluated by annexin V staining of the cells and flow cytometry. Induction of apoptosis is presented as percentage of annexin-positive cells. Data are presented as mean ± SD (*P < 0.05).