Wink Marcia R, Lenz Guido, Braganhol Elizandra, Tamajusuku Alessandra S K, Schwartsmann Gilberto, Sarkis João J F, Battastini Ana M O
Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, Rua Ramiro Barcelos, 2600-anexo, CEP 90035-003 Porto Alegre, RS, Brazil.
Cancer Lett. 2003 Aug 20;198(2):211-8. doi: 10.1016/s0304-3835(03)00308-2.
In order to characterize the enzymes involved in the purine nucleotide catabolism as indicators of invasiveness and aggressiveness of malignant gliomas, the degradation of extracellular nucleotides by five different glioma cell lines was investigated and compared with primary astrocytes. Rapid hydrolysis of extracellular ATP and ADP by astrocytes was observed, whereas all glioma cell lines examined presented low rates of ATP hydrolysis. In contrast, ecto-5'-nucleotidase activity was increased in glioma cell lines when compared to astrocytes. Considering that ATP is recognized as a mitogenic factor that induces proliferation in human glioma cells, the substantial decrease in ATP and ADP hydrolysis observed in gliomas leads us to suggest that alterations in the ecto-nucleotidases pathway may represent an important mechanism associated with malignant transformation of glioma cell lines.
为了将参与嘌呤核苷酸分解代谢的酶作为恶性胶质瘤侵袭性和恶性程度的指标进行表征，研究了五种不同胶质瘤细胞系对细胞外核苷酸的降解情况，并与原代星形胶质细胞进行了比较。观察到星形胶质细胞能快速水解细胞外ATP和ADP，而所有检测的胶质瘤细胞系ATP水解速率较低。相比之下，与星形胶质细胞相比，胶质瘤细胞系中的ecto-5'-核苷酸酶活性有所增加。鉴于ATP被认为是一种能诱导人胶质瘤细胞增殖的促有丝分裂因子，在胶质瘤中观察到的ATP和ADP水解的显著降低使我们认为，ecto-核苷酸酶途径的改变可能是与胶质瘤细胞系恶性转化相关的重要机制。
