LGMN and breast cancer: By contrast, AEP deficiency, even in the absence of external genotoxic insults, resulted in an increase in γH2AX compared to control cells, but not in cleaved caspase 3 levels, reflecting a lack of induction of apoptosis (Fig. 1L, middle and right panels and quantitation), and further reinforcing the role of AEP in genomic stability in BC cells.