TERT and glioblastoma: Two recurrent mutations of TERTp that reach 70–80% frequency in glioblastoma [10, 11] are located − 124 bp and − 146 bp upstream of the TERT translation start site (chromosome 5p15.33: 1,295,228 C > T and 1,295,250 C > T, respectively C228T and C250T).