PIK3CA and glioblastoma: This is in keeping with the observation that mRNA fusions transcripts, including non-druggable fusions, have been identified at high frequency (65%) in glioblastoma [32] Notably all fusions share in common interaction with one or more of the major oncogenic signalling pathways namely RAS/RAF/MEK/MAPK, PI3K/AKT/MTOR, JAK/STAT or PLC/PKC signalling cascades (Table 1).