The PARP-1 Inhibitor Olaparib Causes Retention of γ-H2AX Foci in BRCA1 Heterozygote Cells Following
Exposure to Gamma Radiation
51
5. Conclusion
In summary, this fundamental study of DSB repair kine-
tics in a collection of lymphoblastoid cells mono-allelic
for BRCA1 and BRCA2 indicates that the enhanced radia-
tion sensitivity of BRCA1 heterozygous cells to radiation
in the presence of Olaparib is caused by a persistence of
DNA DSB. We reiterate that cancer patients with BRCA1
mutations may experience unexpectedly severe NTT when
treated with radiotherapy and PARP inhibitors.
6. Acknowledgements
Dr. Emma Bourton was supported by a grant from the
Vidal Sassoon Foundation of America.
We thank Mr. Hussein Al-Ali for assistance with fig-
ure preparation.
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