Cyclin E和p27在人脑星形细胞瘤中的表达和意义

Expression and its significance of cyclin E and p27 in astrocytic tumors

目的检测cyclinE和p27在原发性星形细胞瘤中的表达情况并评价其表达程度与肿瘤病理分级之间的关系。方法应用免疫组化染色法,对46例星形细胞瘤标本和8例非肿瘤脑组织标本中cyclinE和p27的表达情况进行检测,结果用标记指数(LI)表示。结果cyclinE和p27在所有标本中均有不同程度的表达。t检验显示,在对照组和各级别星形细胞瘤之间、对照组与低恶性度组之间、低恶性度组与高恶性度组之间,cyclinE和p27表达程度的差异均有显著性意义(P<0.05)。等级相关分析显示,星形细胞瘤的病理分级与cyclinELI之间呈正相关(r=0.599,P<0.01),与p27LI之间呈负相关(r=-0.732,P<0.01)。同时cyclinELI与p27LI之间也呈明显的负相关(r=-0.754,P<0.01)。结论cyclinE和p27在星形细胞瘤中存在异常的表达,其标记指数与肿瘤病理分级之间有良好的相关性。cyclinE和p27的表达程度可作为反映星形细胞瘤恶性程度的参考指标,两者联合应用时意义更大。

Objective To examine the cxpression of cyclin E and p27 in primary astrocyfic tumors and to investigate the relationship between expression of these cell-cycle regulators and tumor histopathologic grades. Tissue sanrples of primary astrocyfic tumors （n =46） and non-tumor brain tissues （n =8） were graded according to World Health Organization criteria （WHO grade 1, n = 10; grade 2, n =9; grade 3, n = 15; grade 4, n = 12）. Expression of cyclin E and p27 protein was immunohistochemically investigated. Dark brown stains in the nuclei were considered positive for both cyclin E ＇and p27. The labeling indexes of cyclin E and p27 were calculated under microscopical field at a magnification of 403 x by counting at least 1 030 tumor cells from selected fields. Results All of 54 specimens studied were positive for both cyclin E and p27. The cyclin E labeling index （LI） ranged from 0.5% to 31.6%, with a mean value of 13.59%±9.（6%. The p27 LI ranged from 3.6% to 92.2%, with a mean value of 44.52%±25.22%. 3here was a significant difference between the expression of cyclin E or p27 among non-tumor brain tissues, low-grade astrocytic tumors and high-grade astrrocytic tumors （P 〈0.05）. The relationship mnong the histopatholngic grades of tumors, cyclin ELI and p27 LI was analyzed. The cyclin E 11 tended to increase with tumor grades （r=0.599, P〈0.01） and the p27 LI decreased significantly with tumor grades （r = -0.732, P 〈0.01 ）. A strongly negative correlation was shown between cyclin E LI and p27 LI （r = -0.754, P〈0.01）.Condusion Expression of cyclin E and p27 protein is deregulated in primary astrecytic tumors. The tumor grades positively correlated with cyclin ELI and negatively correlated with p27 LI. There is a strongly negative correlation between cyclin ELI and p27 LI. The expression of cyclin E and p27 rmy be a useful marker for assessing the histopathologic grades of astrecytic tumors. The combined analysis of cyclin E and p27 expression is corrsidered to be retire reliable.