Laaksonen A M, Hänninen O O, Mäntyjärvi R A
Carcinogenesis. 1984 Apr;5(4):489-94. doi: 10.1093/carcin/5.4.489.
Secondary cultures of newborn NMRI nu/nu (nude) mouse skin fibroblasts were used as targets for transformation by the combined administration of SV40 and 3-methylcholanthrene (MC). The SV40-induced transformation was enhanced both by pre- and post-treatment with MC at concentrations which themselves were nontransforming. The short pretreatment caused a 2-fold enhancement in the transformation frequency at a low concentration of MC that allowed greater than 50% of the cells to survive. A short post-treatment also caused a concentration dependent enhancement in SV40 transformation of the same magnitude. The long (72 h) post-treatment with MC increased virus transformation as much as 4.3-fold. In contrast, anthracene, a non-carcinogenic compound, had no effect on the viral transformation frequency. An analysis of the morphology of the foci revealed that long post-treatment with MC induced a high number of type I foci. Combination dishes lacked these foci almost completely, and the enhancement was due to the increased number of type II and type III foci.
新生NMRI裸鼠皮肤成纤维细胞的传代培养物被用作通过联合施用SV40和3-甲基胆蒽（MC）进行转化的靶标。在本身不具有转化能力的浓度下，MC的预处理和后处理均增强了SV40诱导的转化。短时间预处理在低浓度MC下使转化频率提高了2倍，该浓度下超过50%的细胞能够存活。短时间后处理也导致SV40转化在浓度依赖性方面有相同程度的增强。MC长时间（72小时）后处理使病毒转化增加了4.3倍。相比之下，非致癌化合物蒽对病毒转化频率没有影响。对病灶形态的分析表明，MC长时间后处理诱导了大量I型病灶。联合培养皿几乎完全缺乏这些病灶，增强是由于II型和III型病灶数量增加。
