While siRNA-mediated knockdown of DKK3 in H460 lung cancer cells has been recently shown to cause apoptosis and increased levels of p53, p21CIP1 and BAX 39, we demonstrate that DKK3-shRNA mediated knockdown had no effect on phospho-p53 and BAX levels but increased p27KIP1 and reduced p21CIP1 levels. This evidence concerns the gene CDKN1B and lung carcinoma.