COX-2 knockdown reverses TRAIL-resistance in MCF7 spheroid and monolayer cells.

(A) qPCR and western blot data showing the relative expression of COX-2 gene (n = 3) and COX-2 protein in control siRNA and COX-2 siRNA transfected MCF7 cells. (B) Flow cytometry histograms and (C) western blot analysis comparing the expression of DR4 in MCF7 cells transfected with control siRNA and COX-2 siRNA cultured as monolayer and spheroids. (D) Bright field images and (E) MTT assay results (n = 5) quantifying the effect of 200 ng/mL of TRAIL in control siRNA and COX-2 siRNA transfected cells cultured as monolayer and spheroids.