Dzhandzhugazyan K N, Kirkin A F, thor Straten P, Zeuthen J
Department of Tumor Cell Biology, Institute of Cancer Biology, Danish Cancer Society, Copenhagen, Denmark.
FEBS Lett. 1998 Jul 3;430(3):227-30. doi: 10.1016/s0014-5793(98)00603-6.
Ecto-ATPase activities of melanocytes and human melanoma cell lines differing in the stage of progression were compared. A dramatic increase in ecto-ATPase activity above the level of normal melanocytes was demonstrated in the differentiated melanomas and was followed by a gradual decrease with tumor progression. The characteristics of this enzymatic activity were consistent with CD39/ecto-ATP diphosphohydrolase (ATPDase) which was found to be the major ecto-ATP-hydrolysing enzyme in melanomas. Indeed, the expression of CD39 and the level of CD39 mRNA followed a similar pattern. Since CD39 is known to regulate homotypic adhesion and, supposedly, affects the disaggregation step, we suggest that overexpression of CD39 may enable tumor cells to reduce contacts with T-lymphocytes and escape from immunological recognition.
比较了不同进展阶段的黑素细胞和人黑色素瘤细胞系的ecto-ATP酶活性。在分化型黑色素瘤中，ecto-ATP酶活性显著高于正常黑素细胞水平，随后随着肿瘤进展逐渐降低。这种酶活性的特征与CD39/ecto-ATP二磷酸水解酶（ATPDase）一致，后者被发现是黑色素瘤中主要的ecto-ATP水解酶。事实上，CD39的表达和CD39 mRNA水平呈现相似的模式。由于已知CD39调节同型黏附，并且推测会影响解聚步骤，我们认为CD39的过表达可能使肿瘤细胞减少与T淋巴细胞的接触并逃避免疫识别。
