Radiosensitivity of HCV cells and their v-ras and v-raf transfectants

In the present work, it was found that transfection of cultivated urothelial cells HCV-29 with v-raf and v-ras oncogenes increased their sensitivity to ionizing radiation, as documented by clonogenic studies. Flow cytometry study showed, that HCV-29 and their v-ras transfectants were arrested around middle S phase, whereas v-raf transfectants randomly at each point of S phase. This unusual reaction of HCV-29 v-raf cells may partially explain studies of P 21 WAF 1 /CIP 1 and GADD 45 genes, whose transcripts were found only in these cells. Increased radiosensitivity of v-ras transfectants is probably associated with c-JUN protein overexpression. Altogether the obtained results suggested different mechanism of reaction on irradiation of v-raf and v-ras transfected cells.