Nakano S, Bruce S A, Ueo H, Ts'o P O
Cancer Res. 1982 Aug;42(8):3132-7.
We have developed a qualitative and quantitative assay system for detecting cells lacking postconfluence inhibition of cell division (contact insensitivity, CS-) in golden Syrian hamster embryo cells in culture by measuring the number of cells able to form colonies on a lethally irradiated, confluent monolayer of a contact-sensitive established cell line. A subpopulation in normal low-passage cultures of golden Syrian hamster embryo cells temporarily exhibits this CS- phenotype at very low frequency (approximately 4 x 10(-3)) but quickly loses the property within a few passages in vitro. This phenotype is invariably exhibited by various tumorigenic cell lines at very high frequency (7 to 50 x 10(-2)) and appears to correlate with the anchorage-independent growth phenotype. The temporal acquisition of the CS- phenotype by tertiary-passage golden Syrian hamster embryo cells following exposure to N-methyl-N'-nitro-N-nitrosoguanidine was examined. Cells with a stably heritable CS- phenotype are detected after approximately 20 posttreatment population doublings. In contrast, anchorage-independent cells are not detected until 35 to 95 posttreatment population doublings. These CS- cells appear to be preneoplastic cells, since clonally isolated CS- cells did not exhibit anchorage-independent growth until further passaging in vitro. The results suggest that acquisition of the CS- phenotype represents an early stage in neoplastic progression.
我们开发了一种定性和定量检测系统，通过测量在经致死剂量照射的、汇合的接触敏感的已建细胞系单层上能够形成集落的细胞数量，来检测培养的金黄叙利亚仓鼠胚胎细胞中缺乏汇合后细胞分裂抑制（接触不敏感性，CS-）的细胞。在金黄叙利亚仓鼠胚胎细胞的正常低代培养物中，一个亚群以非常低的频率（约4×10⁻³）暂时表现出这种CS-表型，但在体外传代几次后很快就会失去该特性。各种致瘤细胞系总是以非常高的频率（7至50×10⁻²）表现出这种表型，并且似乎与不依赖贴壁生长表型相关。研究了三代传代的金黄叙利亚仓鼠胚胎细胞在暴露于N-甲基-N'-硝基-N-亚硝基胍后对CS-表型的短暂获得情况。在处理后约20次群体倍增后可检测到具有稳定遗传的CS-表型的细胞。相比之下，直到处理后35至95次群体倍增才检测到不依赖贴壁的细胞。这些CS-细胞似乎是肿瘤前细胞，因为克隆分离的CS-细胞在体外进一步传代之前并未表现出不依赖贴壁生长。结果表明，CS-表型的获得代表了肿瘤进展的早期阶段。
