Targeting RNA‐binding motif protein 39 for arginine reduction: unveiling metabolic vulnerability in arginine‐dependent liver cancer

Abstract Cancer is increasingly acknowledged as a metabolic disease, characterized by metabolic reprogramming as its hallmark. However, the precise mechanisms behind this phenomenon and the factors contributing to tumorigenicity are still poorly understood. In a recent publication in Cell, Mossmann and colleague reported a study unveiling arginine as a molecule with second messenger‐like properties that reshapes metabolism to facilitate the tumor development in hepatocellular carcinoma (HCC). Their research revealed that the RNA‐binding motif protein 39 (RBM39)‐mediated increase in asparagine synthesis results in increased arginine uptake. This establishes a positive feedback loop that sustains elevated levels of arginine and facilitates oncogenic metabolic reprogramming. Additionally, Mossmann et al. demonstrated that depleting RBM39 with indisulam effectively disrupts the proto‐oncogenic metabolic reprogramming in HCC. This discovery presents a novel treatment strategy for arginine‐dependent liver cancers.