Diffuse Gliomas with FGFR3-TACC3 Fusions: Oncogenic Mechanisms, Hallmarks, and Therapeutic Perspectives

In 2012, whole-transcriptome sequencing analysis led to the discovery of recurrent fusions involving the FGFR3 and TACC3 genes as the main oncological driver in a subset of human glioblastomas. Since then, FGFR3-TACC3 fusions have been identified in several other solid cancers. Further studies dissected the oncogenic mechanisms of the fusion protein and its complex interplay with cancer cell metabolism. FGFR3-TACC3 fusion-driven gliomas emerged as a defined subgroup with specific clinical, histological, and molecular features. Several FGFR inhibitors were tested in FGFR3-TACC3 fusion-positive gliomas and proved some efficacy, although inferior to the results seen in other FGFR3-TACC3 fusion-driven cancers. In this review, we summarize and discuss the state-of-the-art knowledge resulting from a 10-year research effort in the field, its clinical implications for glioma patients, the potential reasons for targeted therapy failures, and the perspective of emerging treatments.