Harlos J P, Weiss L
Int J Cancer. 1983 Dec 15;32(6):745-50. doi: 10.1002/ijc.2910320615.
The peripheries of Lewis lung (3LL) tumor cells growing in different organs of the mouse were studied by cell electrophoresis and electron microscopic quantitation of colloid iron hydroxide (CIH) adsorption before and after incubation with neuraminidase. The results show that cells growing in the kidney after direct injection have significantly higher anodic mobilities than cells growing in the subcutaneous sites from which they were derived, or in intramuscular sites, liver or spleen. The proportional contributions of cell surface sialic acids were similar in all sites. Electron microscopy of cells reacted with CIH indicates that the increased surface charge density of the tumor cells growing in the kidney is due to the presence of increased densities of non-CIH-binding ionogenic groups. Before neuraminidase treatment, the surface distribution patterns of CIH were indistinguishably random for 3LL cells growing in all sites. After neuraminidase treatment, significantly more clustering of CIH particles was observed on 3LL cells with a history of growth in the kidney than in subcutaneous sites. The changes observed in the 3LL cells growing in the kidney were irreversible, and persisted on multiple back-transplantation to subcutaneous sites. Detailed analysis of the results shows the changes to be due to the preferential selection of a subpopulation consisting of approximately 10% of the original (subcutaneous) tumor-cell population. This evidence for an irreversible site-induced selection of a pre-existing sub-population of 3LL cells contrasts with the reversible (modulation) site-induced adaptation previously observed by us in Walker-256 cancer cells, and therefore indicates that both selective and adaptive processes can occur. Even in the case of the 3LL cells, site-specific selection is not general, since the changes were observed in tumors growing in the kidney but not in the other anatomic sites. At present we cannot comment on the relevance of these reported changes to naturally occurring metastasis.
通过细胞电泳以及对用神经氨酸酶孵育前后的氢氧化胶体铁（CIH）吸附进行电子显微镜定量分析，研究了生长在小鼠不同器官中的Lewis肺癌（3LL）肿瘤细胞的周边情况。结果显示，直接注射后在肾脏中生长的细胞，其阳极迁移率显著高于源自皮下部位并在皮下部位、肌肉内、肝脏或脾脏中生长的细胞。细胞表面唾液酸的比例贡献在所有部位相似。与CIH反应的细胞的电子显微镜检查表明，在肾脏中生长的肿瘤细胞表面电荷密度增加是由于非CIH结合离子ogenic基团密度增加所致。在神经氨酸酶处理之前，在所有部位生长的3LL细胞的CIH表面分布模式均无明显差异，呈随机分布。神经氨酸酶处理后，在有肾脏生长史的3LL细胞上观察到的CIH颗粒聚集明显多于皮下部位。在肾脏中生长的3LL细胞中观察到的变化是不可逆的，并且在多次回植到皮下部位后仍然存在。对结果的详细分析表明，这些变化是由于优先选择了由原始（皮下）肿瘤细胞群体中约10%组成的亚群。这种关于3LL细胞预先存在的亚群的不可逆位点诱导选择的证据与我们之前在Walker-256癌细胞中观察到的可逆（调节）位点诱导适应形成对比，因此表明选择性和适应性过程都可能发生。即使在3LL细胞的情况下，位点特异性选择也不普遍，因为在肾脏中生长的肿瘤中观察到了变化，而在其他解剖部位未观察到。目前我们无法评论这些报道的变化与自然发生的转移的相关性。
