As p21 has a positive role in cell differentiation, in contrast to that of c-Myc and CD44, it appeared that through down-regulation of miR-20a, -93, and -106b expression, CA stabilized the 3' UTR of p21 mRNA, increased the intracellular level of p21 protein, and triggered the differentiation cascade in tumor cells. The gene discussed is CD44; the disease is neoplasm.