To further verify that the DraE-ΔSS protein cannot form Dr fimbriae on bacterial surface, we analyzed the adhesion of fluorescent E. coli strains to urinary bladder cancer cells, to which Dr fimbriae specifically bind via the surface located CD55, CD66a, CD66c, and CD66e human protein receptors (23). This evidence concerns the gene CEACAM6 and urinary bladder cancer.