B16N melanoma cells stably expressing GFP-luciferase were injected into syngeneic WT and EGR4-/- mice by tail vein injection. (B-D) Mice were sacrificed on day 20 and tumors were counted. Data is presented as total/mouse (B), N=9 for each gender and genotype. Differences in luciferase activity measured by IVIS in Panel A were determined by two-way ANOVA. Changes in luciferase activity were significantly altered in EGR4 knockout mice (P < 0.0112). 