Modeling the Neuropathology of Tuberous Sclerosis with Human Stem Cells Reveals a Role for Inflammation and Angiogenic Growth Factors [Treatment]

Tuberous sclerosis complex (TSC) is a rare genetic disease characterized by mTOR hyperfunction induced benign tumor growths in multiple organs and neurological symptoms. Because the molecular pathology is highly complex and the etiology poorly understood we employed a defined human neuronal model with a single mTOR activating mutation to dissect the disease-relevant molecular responses driving the neuropathology. TSC2 deficient neural stem cells showed severely reduced neuronal functional maturation and characteristics of astrogliosis instead. Accordingly, transcriptome analysis uncovered an inflammatory response and increased metabolic activity, while ribosome profiling revealed excessive translation of ribosomal transcripts and higher synthesis rates of angiogenic growth factors. Treatment with mTOR inhibitors corrected translational alterations but not transcriptional dysfunction. These results extend our understanding of the molecular pathophysiology of TSC brain lesions, and suggest phenotype-tailored pharmacological treatment strategies.