And p53 was a downstream regulator of miR-21, overexpression of miR-21 inhibited the expression of p53 following ischemia in vitro and in vivo, while inhibition of miR-21 in vitro and in vivo promoted p53 expression following ischemia, suggesting miR-21/p53 axis may play a potential role in ischemia. The gene discussed is TP53; the disease is ischemia.