We next designed 8 deletion variants (del1 −455/−345; del2 −345/−247; del3 −247/−125; del4 −125/−5; del5 −5/+118; del6 +118/+220; del7 +220/+319; del8 +319/+368) of cxcr5 promoter (Figure 3B) to systematically identify the regions responsible for p53-dependent regulation of cxcr5 promoter in breast cancer cells. This evidence concerns the gene TP53 and breast carcinoma.