Deichman G I
Institute of Carcinogenesis, Academy of Medical Sciences, Moscow, USSR.
Cancer Surv. 1988;7(4):675-90.
In cells transformed in vitro by different agents we have identified two discrete characteristics essential for in vivo selection by the effectors of host natural resistance. These two biochemically distinct characteristics, ie resistance to hydrogen peroxide and ability to secrete E type prostaglandin (PGE) in contact with NK cells, macrophages and neutrophils, may both be expressed either in about 100% of cells transformed by Rous sarcoma virus, or in less than 0.1% of cells transformed spontaneously. The expression of these characteristics provides the cells with selective advantages in vivo and determines the level of their tumorigenic activity and experimental metastasis-forming activity. These characteristics are apparently necessary, but insufficient, for spontaneous metastasizing activity. Demonstrated NK resistance of malignant cell variants is directly connected with their ability to produce PGE. The in vitro transformed cells which do not possess these qualities apparently have no ability for in vivo survival and growth. Though these two cellular properties are connected with biochemically different pathways (catabolism of H2O2 and metabolism of arachidonic acid) they are jointly expressed, or not expressed, in transformed cells. The possible mechanisms of in vivo selection of malignant cell variants, with one or a few cell properties united in clusters, and the dual role of natural resistance in this process are discussed.
在由不同因子体外转化的细胞中，我们已经鉴定出宿主自然抵抗力效应物在体内选择所必需的两个离散特征。这两个生化特性不同的特征，即对过氧化氢的抗性以及在与自然杀伤细胞、巨噬细胞和中性粒细胞接触时分泌E型前列腺素（PGE）的能力，可能在约100%由劳斯肉瘤病毒转化的细胞中表达，也可能在自发转化细胞中不到0.1%的细胞中表达。这些特征的表达赋予细胞在体内的选择优势，并决定其致瘤活性和实验性转移形成活性的水平。这些特征显然是自发转移活性所必需的，但并不充分。已证明恶性细胞变体对自然杀伤细胞的抗性与其产生PGE的能力直接相关。不具备这些特性的体外转化细胞显然没有在体内存活和生长的能力。尽管这两个细胞特性与生化途径不同（过氧化氢的分解代谢和花生四烯酸的代谢），但它们在转化细胞中共同表达或不表达。讨论了具有一个或几个聚集在一起的细胞特性的恶性细胞变体在体内选择的可能机制，以及自然抵抗力在此过程中的双重作用。
