[Expression of proteasome ß5 subunit in human atherosclerotic plaque].

OBJECTIVE: To evaluate the expression of proteasome ß5 subunit in human atherosclerotic plaque. METHODS: The specimens of carotid endarterectomy were collected from 16 carotid stenosis patients. For the case group, they were divided into 2 groups: plaque (group A) and areas adjacent to plaque (group B). And carotid endarterium was obtained from 6 patients undergoing aortic replacement surgery. Relatively normal arterial intima (subclavian artery & innominate artery) was selected as the control group (group C). Content of proteasome ß5 subunit was evaluated by hematoxylin & eosin (HE) staining, immunohistochemistry and Western blot. RESULTS: (1) In patients with diabetes, hyperlipidemia and probable smoking, proteasome ß5 subunit was enhanced in all groups; (2) Proteasome ß5 subunit was demonstrated in both cytoplasm and nucleus of vascular smooth muscle cells, but mainly confined to cytoplasm; (3)The positive expression rate of ß5 was 9/16 in group A, 11/16 in group B and 6/6 in group C. There was significant divergence in the expression of ß5 in different sample sub-groups: group A (atherosclerotic plaque) < group B (areas adjacent to plaque) < group C (control group). CONCLUSION: The expression of ß5 decrease markedly in human atherosclerotic plaques.

Immunohistochemical study on p53, H-rasp21, c-erbB-2 protein and PCNA expression in HCC tissues of Han and minority ethnic patients.

AIM:To find out the difference of human primary liver carcinogenesis between Han and minority ethnic patients in Xinjiang.METHODS:Expression of p53, c-erbB-2, H-rasp21 protein and proliferating cell nuclear antigen (PCNA) in tumor tissues of 50 patients (Han 38, minority 12) with primary hepatic carcinoma was detected by immunohistochemistry (LSAB).RESULTS:The positive frequency of p53, c-erbB-2, H-rasp21 and PCNA expression was 46.0% (23/50), 70.0% (35/50), 68.0% (34/50) and 82.0% (41/50) in tumor tissues; 4.0% (2/50), 22.0% (11/50), 64.0% (32/50) and 52.0% (26/50) in peritumors respectively and a significant difference, except for H-rasp21, of oncogene alteration was found (P < 0.05) between tumor and non-tumorous tissues. Combined the three oncogenes alteration, 26% (13/50) tumor tissues had positive immunoreactivity, but in peritumor and normal livers it was negative. The positive rate of p53, c-erbB-2 and H-rasp21 protein expression was 39.5% (15/38), 60.5% (23/38) and 39.5% (15/38) in tumors of Han patients; 66.7% (8/12), 100% (12/12) and 75.0% (9/12) in minorities respectively, with statistical difference (P<0.05).CONCLUSION:Overexpression of p53,c-erbB-2 and H-rasp21 in human primary liver carcinoma is an important biomarker of genetic alteration. The different frequency of these oncogenetic changes may reflect some environmental or/and ethnic hereditary factors affecting the liver carcinogenesis. The special life style of Han, Uygur, Kazak and Mongolia nationalities in Xinjiang may also be related to the etiopathogenesis of this disease.