Fig. 3.

Chernobyl bank vole fibroblasts survive on higher concentrations of DNA damaging drugs than control cells. Cells were plated at 80% confluency and treated with different concentrations of the DNA damaging drugs for 24 h after which fresh cell culture media was changed and the cells were let to grow for 7 days before scoring the wells that were 100% confluent. Treatment with a.) cisplatin or b.) doxorubicin did not show significant difference between the Chernobyl and control cell lines, whereas Chernobyl cells were able to grow in, on average, about 30 μM higher concentrations of c.) etoposide. For constant exposure of DNA damaging drugs cells were treated with the drug every other day for four times before scoring the wells that were 100% confluent. Chernobyl fibroblasts were able to grow in significantly higher chronic concentrations of D.) cisplatin, e.) doxorubicin and f.) etoposide than control cells. Examples from one experiment (N = 8) on the effect of constant drug treatment on reduction of 100% confluent Chernobyl and control fibroblast cultures after treatment with g.) cisplatin, h.) doxorubicin, and i.) etoposide. Results, except g-i, are from three separate experiments using eight Chernobyl (N = 24) and eight control (N = 24) cell lines, variation is shown by standard deviation, and statistical analysis was done with Student’s t-test (ns = p > 0.05, * = p ≤ 0.05, ** = p ≤ 0.01, *** = p ≤ 0.001)