ATM and cancer: MST-312 also provokes G2/M cell cycle arrest and acute ATM-pathway-dependent DNA damage in breast and brain cancer cells.[9–12] Therefore, we sought to investigate the anti-cancer effects of a combinatorial approach on targeting telomerase by MST-312 and plumbagin treatment, in TNBC MDA-MB-231 and luminal MCF-7 breast cancer cells as compared to the relative normal MCF-10A cell type.