Rosen N, Bolen J B, Schwartz A M, Cohen P, DeSeau V, Israel M A
J Biol Chem. 1986 Oct 15;261(29):13754-9.
We have evaluated the level of pp60c-src protein kinase activity in a variety of human tumor tissues and human tumor cell lines, and have estimated the abundance of the c-src protein in several of these tissues and cell lines. All cell lines derived from tumors of neuroectodermal origin that express a neural phenotype were found to possess c-src molecules with high levels of tyrosine-specific protein kinase activity. In contrast, cell lines derived from tumors of neuroectodermal origin that do not express neural characteristics, such as glioblastomas and melanomas, were found to have pp60c-src molecules with low levels of protein kinase activity. A similar pattern was observed when we analyzed the activity of c-src molecules extracted directly from corresponding tumor tissues. Analysis of human tumor cell lines derived from tissues other than those of neuroectodermal origin revealed that pp60c-src protein kinase activity was low in most cases. Exceptions to this observation were all rhabdomyosarcoma, osteogenic sarcoma, Ewing's sarcoma, and colon carcinoma lines tested. Comparison of pp60c-src kinase activity in normal skeletal muscle and rhabdomyosarcoma tissue and in normal breast tissue and breast adenocarcinoma tissue revealed that pp60c-src kinase activity was specifically elevated in the tumor tissues in both cases. However, the amount of pp60c-src protein in both normal and tumor tissues was found to be similar. These observations suggest that increases in the specific activity of the pp60c-src phosphotransferase in some rhabdomyosarcomas and breast carcinomas may be a characteristic acquired during the malignant transformation of the cells that is retained in cell lines established from these tumors.
我们评估了多种人类肿瘤组织和人类肿瘤细胞系中pp60c-src蛋白激酶的活性水平，并估算了其中几种组织和细胞系中c-src蛋白的丰度。所有源自表达神经表型的神经外胚层起源肿瘤的细胞系，均被发现含有具有高水平酪氨酸特异性蛋白激酶活性的c-src分子。相比之下，源自不表达神经特征的神经外胚层起源肿瘤的细胞系，如成胶质细胞瘤和黑色素瘤，被发现具有低水平蛋白激酶活性的pp60c-src分子。当我们分析直接从相应肿瘤组织中提取的c-src分子的活性时，观察到了类似的模式。对源自神经外胚层起源以外组织的人类肿瘤细胞系的分析表明，在大多数情况下，pp60c-src蛋白激酶活性较低。该观察结果的例外情况是所有测试的横纹肌肉瘤、骨肉瘤、尤因肉瘤和结肠癌细胞系。正常骨骼肌与横纹肌肉瘤组织以及正常乳腺组织与乳腺腺癌组织中pp60c-src激酶活性的比较表明，在这两种情况下，肿瘤组织中的pp60c-src激酶活性均有特异性升高。然而，正常组织和肿瘤组织中pp60c-src蛋白的量相似。这些观察结果表明，某些横纹肌肉瘤和乳腺癌中pp60c-src磷酸转移酶的比活性增加，可能是细胞恶性转化过程中获得的一种特征，并保留在从这些肿瘤建立的细胞系中。
