Figure 7. BRCA1 may regulate IR-induced apoptosis through the intrinsic pathway.
(A) Caspase 9 cleavage. HCC1937 cells were transfected with either vector control, wild type (WT) BRCA1, or mutant (S988A, C64G, or P1749R) BRCA1. Twenty-four hours following transfection, cells were subjected to mock or 6 Gy IR. Whole cell lysates were then harvested 40 hours following IR and subjected to SDS-PAGE and western blot analysis for caspase 9. Actin was the loading control. (B) Quantification of cleaved caspase 9 via densitometry. Shown is the average from at least 3 independent experiments. Error bars represent the SEM (**p<0.001).