The inhibition of Slug, Snail or Twist action through interfering RNA (siRNA)or antisense transfer resulted in tumor metastasis or growth inhibition and increased sensitivity to the cytotoxic agents used in chemotherapy for solid cancers [29,44-46]These results strongly suggest the relation between EMT markers induction including Slug, Snail and Twist but also between anti-Slug, Snail or Twist treatment and improvement of bladder cancer chemotherapy. This evidence concerns the gene SNAI1 and urinary bladder carcinoma.