基质金属蛋白酶2及其抑制物在人胶质瘤中的表达

目的：探讨基质金属蛋白酶2（MMP-2）及其组织抑制物2（TIMP-2）在人胶质瘤的表达特点。方法：按WHO病理分级标准将35例人胶质瘤标本分为4组：Ⅰ级7例，Ⅱ级12例，Ⅲ级10例，Ⅳ级6例。另取4例正常脑组织作为对照。用免疫组化方法检测MMP-2和TIMP-2的表达，分析二者表达强度及阳性染色率与病理分级的关系。结果：MMP-2和TIMP-2阳性染色主要位于胶质瘤细胞浆和细胞外基质。在Ⅰ~Ⅳ级胶质瘤，MMP-2的阳性细胞染色率(%)分别为10.42±3.95、29.92±7.69、45.40±9.01和57.17±11.39，表达强度(分值)分别为2.14±0.38、3.17±0.71、4.00±0.70和5.83±0.41，均随胶质瘤恶性程度的增加而增加；而TIMP-2的细胞阳性染色率(%)分别为51.81±12.28、36.42±9.68、22.10±7.71和4.33±1.63，表达强度(分值)分别为5.57±0.53、3.92±0.29、2.70±0.50和2.17±0.41，均随恶性程度的增加而明显降低。随着胶质瘤恶性程度的增加，MMP-2/TIMP-2比值明显升高。胶质瘤MMP-2和TIMP-2的表达水平之间呈明显负相关（r＝－0.69，P<0.05）。结论：MMP-2和TIMP-2在人胶质瘤的侵袭生长中共同起重要作用。

Expressions of matrix metalloproteinase-2 and its inhibitor in human glioma

Objective To investigate the expressions of matrix metalloproteinase-2(MMP-2, gelatinase A)and its inhibitor,tissue inhibitor of metalloproteinase-2(TIMP-2),in human glioma. Methods The samples from 35 cases of glioma were divided into four groups according to the WHO classification: grade Ⅰ (n=7), grade Ⅱ (n=12), grade Ⅲ (n=10), and grade Ⅳ (n=6), 4 normal brain samples were served as the control. The expressions of MMP-2 and TIMP-2 protein were determined with immunohistochemistry in the samples, and the correlation between the expressions of MMP-2, TIMP-2 and malignant degree of the gliomas was analyzed. Results The positive staining was localized in the cytoplasm of glioma cells and extracellular matrix. In the gliomas from gradeⅠ to gradeⅣ, the positive staining rates (%)(10.42±3.95,29.92±7.69,45.40±9.01, and 57.17±11.39, respectively) and the expression intensities (2.14±0.38,3.17±0.71,4.00±0.70, and 5.83±0.41, respectively) of MMP-2 were significantly elevated with the malignant grade of the gliomas, while the positive staining rates (%)(51.81±12.28,36.42±9.68,22.10±7.71, and 4.33±1.63, respectively) and immunostaining intensities (5.57± 0.53,3.92±0.29,2.70±0.50, and 2.17±0.41, respectively) of TIMP-2 were markedly reduced with increasing the grade of glioma malignancy. The ratioes of MMP-2/TIMP-2 were obviously increased when the malignant grades of the gliomas were elevated. There was a negative correlation (r=-0.69,P<0.05) between MMP-2 and TIMP-2 expressions in the gliomas. Conclusion MMP-2 and TIMP-2 together play an important role in invasiveness of human glioma.