library_construction_protocol: Total RNA was extracted from glioblastoma tissue using TRIzol reagent (Life Technologies, Carlsbad, CA, USA). A total of 1 µg total RNA per sample was used as input material for the lncRNA  library preparation. Strand-specific libraries were generated using NEBNext® UltraTM  RNA Library Prep Kit for Illumina® (NEB, USA) following manufacturer's  recommendations and index codes were added to attribute sequences to each sample.