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

Figure 3

Effects of the combined treatment of cetuximab and cisplatin on the expression of EGFR, MAP kinase, and related signaling proteins. HCT116 and SW480 cells were treated with cetuximab (30 μg/mL) or cisplatin (2 μg/mL) alone or the combination of both agents, for 24 h. (a) Expression of p-EGFR, EGFR, p-p38 MAPK, p38 MAPK, p-ERK, or ERK was detected by Western blotting using specific antibodies. (b) Cleaved caspase-3 was detected by Western blotting. (c) Expression of IL-8 mRNA was detected by RT-PCR using specific primers. Expression of COX-2 was detected by Western blotting. The β-actin protein was used as a loading control. After densitometric quantification, 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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