[The secretion of type-E prostaglandins and the sensitivity to hydrogen peroxide of Syrian hamster clone cells transformed by the Rous sarcoma virus]. / Sekretsiia prostaglandinov tipa E i chuvstvitel'nost' k perekisi vodoroda klonov kletok siriiskogo khomiachka, transformirovannykh virusom sarkomy Rausa.

Seven clonal sublines of the strain of syrian hamster embryo cells transformed in vitro by the Rous sarcoma virus were obtained. All clones possessed both high resistance to damage by hydrogen peroxide and a capacity to release E-type prostaglandins in response to contact with NK-cells in vitro. The clones did not differ from each other and from the parent population in respect to these qualitative properties. Possible relation between these two properties and their role in resistance of transformed cells to cytotoxic activity of macrophages, neutrophils and NK-cells and thus to their ability to survive in vivo are discussed.

[Differences in the distribution of proviruses in low- and highly- metastatic variants of hamster cells, transformed by Rous sarcoma virus]. / Razlichiia v raspredelenii provirusov v nizko- i vysoko- metastaticheskikh variantakh kletok khomiakov, transformirovannykh virusom sarkomy Rausa.

The structure of provirus in Syrian hamster cells, transformed by Rous sarcoma virus (RSV) varying in metastatic capability in vivo has been analysed. The original cell line and its low metastatic variants contain only one copy of the integrated RSV genome. The DNA of highly metastatic cell lines cloned from the same primary culture, contain an additional copy of provirus. This RSV copy in different highly metastatic variants has a similar integration site.