FASN and cancer: For instance, enhanced fatty acid synthase activity in GSDIa may provide a beneficial environment for neoplastic progression, as many malignant tumours, including hepatocellular malignancies, display increased fatty acid synthase activity, whereas fatty acid synthesis inhibition has antitumoural effects.[27], [28], [29] However, whether cellular adaptations in metabolic and/or signal transduction pathways explain the increased risk for (advanced) HCA development in patients with severe G6Pase dysfunction or therapy incompliance remains to be established in future mechanistic studies.