To determine whether ZKSCAN3 down-regulation exerts an influence on the proliferation of bladder cancer cells, we compared cell viability [by methyl thiazolyl disphenyl tetrazolium bromide (MTT) assay] and colony formation (by clonogenic assay) between ZKSCAN3-positive lines versus their knockdown lines. This evidence concerns the gene ZKSCAN3 and urinary bladder cancer.