Apoptosis In Advanced Human Atherosclerosis Plaques And The Expression Of P53,Bcl-2,C-myc

Objectives To explore the significance of human vascular smooth muscle cells(VSMCs) apoptosis in advanced human atherosclerosis plaques and to investigate the expression of P53, Bcl-2 and C-myc.Materials and methods Vascular smooth muscle cells(VSMCs) apoptosis in patient with atherosclerosis and in healthy subjects who injured in accident were studied by means of TdT-mediated dUTP Nick End Labeling (TUNEL)and electron microscopy. P53, Bcl-2 and C-myc protein expression were assessed by immunohistochemistry, and correlation analysis was performed.Results The amount of apoptosis vascular smooth muscle cells in atherosclerosis plaques was significantly higher than that in control group (513.45 + 191.44) cells/1000 cells, vs. (52.00 + 8.49) cells/1000 cells, p<0.001. The expression of P53 and C-myc protein in atherotic plaques was also significantly higher than that in control group (375.40 + 148.83 > 350.10+33.10) cells/1000 cells, vs. (36.40+9.27 ^ 35.30+6.14) cells/1000 cells respectively, p<0.001. The amount of apoptosis vascular smooth muscle cells in atherotic plaques was positively correlated to P53, and C-myc protein expression (r=0.886 and 0.811 respectively, p<0.001). The expression of Bcl-2 protein in atherotic plaques was also significantly lowerthan that in control group(115.40?3.98) cells/1000 cells, vs. (64.20 + 11.67) cells/1000 cells, p<0.001. The amount of apoptosis vascular smooth muscle cells in atherotic plaques was negatively correlated to Bcl-2 protein expression (r=-0.693, pO.OOl). In addition, significantly negative correlation was found between expression of P53, C-myc and Bcl-2 protein in apoptosis Vascular smooth muscle cells. The electron microscopy showed that the characteristics of vascular smooth muscle cellsConclusions Remarkable appearance of apoptosis vascular smooth muscle cells in atherosclerosis plaques was found. It's correlated with P53 and C-myc protein up-regulation and Bcl-2 protein down-regulation. Apoptosis of vascular smooth muscle cells may play a key role in the process of atherosclerogenesis.