Conclusions
Our findings suggest that Elimusertib suppresses the ATR-based Chk1 pathway in TNBC cells. Therefore, ATR inhibition by Elimusertib could be a potential therapeutic strategy especially in tumor protein p53 (p53) mutant TNBC patients.
Methods
The cytotoxic and apoptotic effects of Elimusertib were analyzed by Water-Soluble Tetrazolium 1 (WST-1), Annexin V, cell cycle and acridine orange/propidium iodide staining. Furthermore, Elimusertib induced mitochondrial damage and the intracellular reactive oxygen species were evaluated. Additionally, the inhibition of ATR-Checkpoint kinase 1 (Chk1) DNA damage response and the induction of apoptotic death was analyzed by western blot analysis.
Results
Our preliminary findings revealed that Elimusertib significantly decreased the viability of MDA-MB-231 TNBC cells with toxicity in MCF-10A cells (P<0.05). Elimusertib caused apoptotic death through gap phase (G0)/growth 1 phase (G1) accumulation, caspase-3 activity and mitochondrial damage. Additionally, Elimusertib significantly suppressed the ATR-based DNA damage response and mediated cell cycle checkpoint. Conclusions: Our findings suggest that Elimusertib suppresses the ATR-based Chk1 pathway in TNBC cells. Therefore, ATR inhibition by Elimusertib could be a potential therapeutic strategy especially in tumor protein p53 (p53) mutant TNBC patients.