Activated p53 mediates apoptosis, cell cycle arrest, senescence, DNA repair, or metabolism (Lane and Levine, 2010). The primary structures of p53 and its isoforms are depicted (Figure 2). p53 induces cell cycle arrest by transactivating genes such as cyclin-dependent kinase inhibitor p21, or microRNA miR34. p53 induces apoptosis by transactivating proapoptotic genes such as BAX, PUMA, SCOTIN, and FAS, and inhibiting the antiapoptotic gene BCL-2 (Lane and Levine, 2010). p53 triggers pro-survival or cell death response, depending upon cell types, the intensity of the stress signal, and the extent of cellular damage (Menendez et al., 2009). Also, p53 plays a role in controlling cell motility via regulating the expression of smooth muscle α-actin (Comer et al., 1998), collagens IIα1 and VIα1 (Sun et al., 1999), and many others.