A new study shows that the loss of the TP53 gene in pancreatic ductal adenocarcinoma (PDAC) changes how cancer cells manage acidity, helping them survive in harsh tumor environments. Normally, acidic conditions are toxic, but p53-deficient cells raise their internal pH and ramp up acid-exporting transporters like MCT4 to stay alive.
These p53-lacking tumors also show higher baseline DNA damage and activate backup repair pathways, making them more resilient. While combining ATM inhibitors with PARP inhibitors can kill p53-deficient cells under normal conditions, acidic environments make the cells resistant to this therapy.
Researchers found that blocking pH-regulating transporters alongside DNA-targeting drugs can partially overcome this resistance. The findings reveal how genetic changes and tumor acidity work together to protect aggressive pancreatic cancers and suggest new strategies to make DNA-damaging therapies more effective.