[A new recipient cell line for transfection of biologically active oncogenes]

The properties of the new immortalized rat cell line (REF-1) were analyzed. These cells can be used as recipient ones in transfection assays. REF-1 cells never convert spontaneously to transformed phenotype during long-term passages in vitro unlike NIH3T3 cells. This peculiarity allowed to use REF-1 cells for identification of oncogenes, which induce slow-growing tumors. The following oncogenes were used in gene transfection experiments in order to test their effects: activated human EJ-ras; N-ras; v-myc; v-mos; activated tpr-met and c-hu-met. REF-1 cells, transfected with the members of ras family; v-mos and tpr-met were found to be transformed in vitro and induce tumors in nude mice, on the contrary of c-hu-met- and v-myc-transfected cells, which are non-tumorogenic. A number of clonal cell lines carrying different oncogenes were obtained. The detailed analyses of integration and expression of exogenous sequences of different oncogenes has been presented in 18 clonal cell lines.