TERT Promoter Mutation Analysis in Glioma Samples by Allele-Specific Biochip Hybridization

Objective: Somatic mutations in the promoter of the telomerase reverse transcriptase gene TERT can cause reactivation of telomerase, which stimulates neoplastic processes in the body. C228T and C250T mutations of the TERT promoter (TERTp) are most often found in brain gliomas, for which they are important diagnostic and prognostic markers. Methods: To detect TERTp mutations, an approach involving amplification of the promoter region and subsequent hybridization with immobilized probes on a biological microarray (biochip) has been developed. Results and Discussion: Using this approach, the mutational status of TERTp in 94 glioma samples (astrocytoma, oligodendroglioma, glioblastoma) was investigated. To verify the genotyping results, we used data from Illumina targeted sequencing and Sanger direct sequencing. In total, TERTp mutations were detected in 62 of 94 samples (66%), most commonly in patients with glioblastoma (71%). The C228T mutation (69%) was significantly more frequent compared to the C250T mutation (31%). Conclusions: The results of biochip validation on a collection of clinical samples show that it can be used as a convenient and reliable diagnostic tool in the genetic analysis of CNS tumors.