To determine whether these changes in growth are recapitulated consistently in human cells, we compared the effect of Chiron99021 and Valproic acid on HAB92 colorectal cancer cells (a derivative of HCT116 cells, which are homozygous for wild-type β-catenin)24 transfected with siRNA-targeting Apc or a control (scrambled) siRNA. Consistent with our hypothesis, cells lacking APC were less viable than cells transfected with control siRNA when grown in Chiron99021 or Chiron99021 plus Valproic acid (Fig. 3h). This evidence concerns the gene APC and colorectal cancer.