Figure 1

ERK1 and/or ERK2 shRNA treatment of A375 cells selectively reduces total and phosphorylated levels of respective proteins at days 2, 4 and 6; accompanied by killing of melanoma cells. A. Western blot showing total and phosphorylated protein levels at indicated time intervals following exposure to shRNAs as indicated. SC: scrambled control; E1: ERK1; E2: ERK2; E1/2: ERK1 and ERK2. Actin levels confirm equal loading (left side panel). Data presented is representative of three independent experiments. Right side panel shows the relative density measurement of day 4 treatment levels for indicated proteins. B. Relative killing percentages on days 2, 4, and 6 following exposures to indicated shRNAs. Percentage of dead cells as described in Methods section using Annexin-PI and FACS analysis. Histograms represent the means +/- SEM from four independent experiments. Statistical significance portrayed as follows: *p < 0.002; **p < 0.0001. C. Relative killing percentages on days 2, 4, and 6 following exposures to indicated shRNAs. Percentage of cells undergoing apoptosis (cells with sub-Go DNA content) as described in Methods section Histograms represent the means +/- SEM from three independent experiments. Statistical significance portrayed as follows: *p < 0.03; **p < 0.001.