KRAS on Empty: Lipid Oxidation Blockade Reveals a Metabolic Achilles' Heel in Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer death in the United States, driven by its aggressive biology and high metastatic incidence at diagnosis. With a 5-year survival rate of just 8%, PDAC remains one of the most lethal cancers. Mutant KRAS, present in more than 90% of cases, serves as a key driver of tumorigenesis and metabolic reprogramming. In this issue of Cancer Research, Thakur and colleagues uncover a novel metabolic adaptation that PDAC cells use to survive therapeutic stress. Their integrated metabolomic and lipidomic analyses show that ERK inhibition-targeting a key KRAS pathway effector-not only disrupts glycolysis and glutamine metabolism but also triggers a compensatory increase in fatty acid oxidation (FAO). This shift occurs through lipophagy, a lysosome-mediated lipid degradation process, rather than cytosolic lipolysis. Mechanistically, ERK inhibition promotes the nuclear translocation of TFEB, which drives the upregulation of FAO and lipophagy genes. This metabolic reprogramming enables PDAC cells to survive KRAS pathway blockade. Importantly, cotargeting FAO alongside ERK or KRAS inhibitors elicits a potent synergistic antitumor effect in vivo. This dual-target strategy holds promise for overcoming PDAC resistance to KRAS-targeted therapies, laying the groundwork for novel combination treatments. See related article by Thakur et al., p. 3519.