Aberrant expression of miR-21 changed expression level or phosphorylation of proteins under ox-LDL treatment. A-H. Overexpression or knock down of miR-21 altered the expression level of PDCD4, bax, bad, bcl-2, caspase3 and the phosphorylation of ERK. Data are expressed as mean ± SD; n = 8, *P<0.05.