Integrated Proteogenomics Uncover Mechanisms of Glioblastoma Evolution, Pointing to Novel Therapeutic Targets.

Nearly all glioblastoma (GBM) patients relapse following standard treatment and eventually succumb to disease. While large scale, integrated multi-omic studies have tremendously advanced the understanding of primary GBM at the cellular and molecular level, the post-therapeutic trajectory and biological properties of recurrent GBM remain poorly understood. This knowledge gap was addressed in a recent Cancer Cell article in which Kim and colleagues report on a highly integrative proteogenomic analysis performed on 123 matched primary and recurrent GBMs that uncovered a dramatic evolutionary shift from a proliferative state at initial diagnosis to the activation of neuronal and synaptogenic pathways at recurrence following therapy. Neuronal transition was characterized by post-translational activation of WNT/PCP signaling and BRAF kinase, while many canonical oncogenic pathways, and EGFR in particular, were downregulated. Parallel multi-omics analyses of patient-derived xenograft (PDX) models corroborated this evolutionary trajectory, allowing in vivo experiments for translational significance. Notably, targeting BRAF kinase disrupted both the neuronal transition and migration capabilities of recurrent gliomas, which were key characteristics of post-treatment progression. Furthermore, combining BRAF inhibitor vemurafenib with temozolomide (TMZ) prolonged survival in PDX models. Overall, the results reveal novel biological mechanisms of GBM evolution and therapy resistance, and suggest promising therapeutic intervention.