c-KIT joins the TSC ToolKIT: a new driver of renal cystogenesis.

Tuberous Sclerosis Complex (TSC) is a multisystem disorder marked by benign tumors in brain, lung, and kidney. While the loss-of-function mutations in TSC1 or TSC2 have been known for decades, the molecular basis that converts these mutations into cystic kidney lesions has remained elusive. In this issue of EMBO Molecular Medicine, Zahedi and colleagues now uncover an unexpected culprit: the proto-oncogene receptor tyrosine kinase c-KIT. Their work identifies c-KIT as a pivotal driver of renal cystogenesis in TSC and suggests that its pharmacologic inhibition could complement existing mTOR-targeted therapy.