For GBM, it is becoming increasingly clear that certain molecular and genomic characteristics have important yet undefined immuno-regulatory functions.59,60 In particular, the loss of PTEN has garnered increased clinical significance due to its prevalence in many cancer subtypes, its contributions toward an immunosuppressive TIME, and its recent appreciation for being a prognostic marker for patient response toward immune checkpoint inhibition61. The gene discussed is PTEN; the disease is cancer.