To explore whether vinorelbine and paclitaxel are able to induce p21 expression in AD and AI cells that are deficient in p21, and the possible differences between AD and AI cells in expression of p53 and p21 in response to treatments with vinorelbine or paclitaxel, the resultant levels of p53 and p21 were determined by Western blotting. The gene discussed is TP53; the disease is Alzheimer disease.