CDKN1A and myocardial infarction: It was discovered that lncRNA-p21 is a competing endogenous RNA (ceRNA) for microRNA-466i-5p, so inhibition of lncRNA-p21 promotes the expression of microRNA-466i-5p, thereby inhibiting the expression of Nr4a2 and ultimately inhibiting MI/RI led to infarct size and improved cardiac function.