Increased radiation survival in AT cells upon forced expression of
IGF-IR. (A) Western blot analysis of IGF-IR expression
in GM5849 cells, which lack ATM, and in GM5849 subclones transfected
with a plasmid-expressing IGF-IR driven by a viral promoter.
(B) Clonogenic survival after exposure to IR of
subclones 3 (5849cI3) and 7 (5849cI7), both of which were judged by
Western blot in A to express increased levels of IGF-IR,
in comparison with the parental 5849 AT mutant cells and to an
unrelated wild-type cell line, 637.