Figure 4.

The effect of arsenic trioxide (ATO) and gemcitabine (GEM) on pancreatic cancer cell invasion. (A) Cell invasion was measured using a Transwell assay of Patu8988 and Panc-1 cells after treatment with either 3 µM ATO or 20 µM GEM, or a combination of the two drugs for 20 h. The stained cells were counted using a light microscope in six randomly-selected fields, and the numbers of invaded cells were determined. The number of cells was normalized against the number of cells in the corresponding control cells. (B) The quantitative results are illustrated in (A). *P < 0.05 compared with the control; #P < 0.05 compared with ATO alone or GEM alone. Both: ATO plus GEM.