Fig. 3.

Combination of the STAT3 decoy with gossypol enhances inhibition of cell viability of head and neck cancer cells. A, UM-22B cells were treated with 12.6 nM STAT3 decoy or mutant control decoy for 4 h followed by treatment with 2.67 µM gossypol for 72 h. Cell counts were then performed using trypan blue dye exclusion. Combining the STAT3 decoy with gossypol augmented inhibition of cell viability compared with STAT3 decoy alone, gossypol alone, gossypol alone, or mutant control plus gossypol (p = 0.075, p = 0.2, and p = 0.155, respectively). B, similar results were seen when PCI-15B cells were treated with 38.3 nM STAT3 decoy and 2.97 µM gossypol (p = 0.0278, p = 0.5, and p = 0.0278). Cumulative results are shown from five separate experiments.