Neoplastic Transformation and Cytogenetic Changes after Gamma Irradiation of Human Epithelial Cells Expressing Telomerase

Abstract Riches, A., Peddie, C., Rendell, S., Bryant, P., Zitzelsberger, H., Bruch, J, Smida, J, Hieber, L. and Bauchinger, M. Neoplastic Transformation and Cytogenetic Changes after Gamma Irradiation of Human Epithelial Cells Expressing Telomerase. Neoplastic transformation of human epithelial cells by radiation has previously been investigated using cell lines immortalized with viral vectors. There are disadvantages to this approach, and we report here the results of studies using a human retinal pigment epithelial cell line (340RPE-T53) immortalized by treatment with telomerase. After exposure of the cells to fractionated doses of γ radiation, there was a marked increase in anchorage-independent growth of the surviving cells. The cloned cell lines derived from these anchorage-independent cultures exhibited an increased growth rate in vitro and were serum-independent compared with the parent cell line. The parent cell line maintained a stable diploid karyotype. The cell lines cloned after irradiation wi...