NF-κB factors are the primary regulators of in IL-8 promoter activity A. NF-κB relative activity was evaluated in MDA-MB-231 and MCF-7 cells by transfection of a NF-κB reporter. Results show relative luciferase activities (n=3). B. The importance of NF-κB in IL-8 promoter activity regulation was evaluated by infection of MDA-MB-231 and MCF-7 cells with Ad5 and Ad-IκB viruses (MOI 100) and transfection of xp2-IL8 construct. Results show relative luciferase activities (n=3). C. xp2-IL-8, NF-κB and AP-1 reporters were transfected in MDA-MB-231 cells along with CMV-GAL and control CMV5 or CMV-hERα expression vectors. Cells were treated or not with estradiol (10-8M) for 24h. Results show relative luciferase and CAT activities (n=3).