Synergistic Inhibitory Effects of Cetuximab and Cisplatin on Human Colon Cancer Cell Growth via Inhibition of the ERK-Dependent EGF Receptor Signaling Pathway

Figure 2

Synergistic effects of cetuximab and cisplatin on apoptotic cell death. (a) HCT116 and (b) SW480 cells were treated with cetuximab (30 μg/mL) or cisplatin (2 μg/mL) alone or a combination of both agents, for 24 h; then, apoptotic cells were examined by TUNEL assay. The total number of cells in a given area was determined by using DAPI nuclear staining (blue color). The green color marks TUNEL-positive cells. The apoptotic index was determined as the TUNEL-positive cell number divided by the total cell number (DAPI-stained cells) under fluorescence microscopy (magnification, 200x). Representative images of each experimental group are shown. The data are expressed as the mean ± SD of three independent experiments. indicates statistically significant differences from the control. indicates statistically significant differences from the cetuximab treatment alone.

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