IGSF10 encodes an immunoglobulin superfamily member that functions as a RET receptor tyrosine kinase antagonist with critical roles in neuronal migration and cancer regulation 1. The protein regulates gonadotropin-releasing hormone (GnRH) neuron migration during embryonic development by binding RET and GAS1 to form an inhibitory complex that prevents RET-mediated cdc42 activation 1. IGSF10 is strongly expressed in embryonic nasal mesenchyme during GnRH neuronal migration to the hypothalamus 2. Loss-of-function mutations in IGSF10 cause self-limited delayed puberty by disrupting GnRH neuronal migration, with affected proteins showing intracellular retention and secretion failure 2. IGSF10 mutations are also associated with hypothalamic amenorrhea and combined pituitary hormone deficiency 3. In cancer contexts, IGSF10 expression is typically reduced and correlates with poor prognosis in multiple cancer types including lung adenocarcinoma 45. The protein appears to suppress cancer cell proliferation and invasion through regulation of the integrin-β1/FAK pathway 5. IGSF10 expression correlates with immune cell infiltration in tumors, suggesting additional immunomodulatory functions 64.