Total high-purity RNA of all cell variants was isolated using the total RNA kit peqGOLD (PeqLab, Erlangen, DE) with an additional DNase digestion step according to manufacturer's specifications. RNA-triplicates (3 biological replicates) of each cell line were placed in a 96-well plate in a concentration of at least 150 ng/15 µl RNase-free water. Input total RNA was quantified using the Quant-it RNA Assay (Thermo Fisher, Waltham, USA) and RIN scores were determined using the Agilent Tape Station (Agilent, Santa Clara, USA). All RIN scores were > 8. 200 ng input total RNA were processed using the Illumina stranded mRNA kit (Illumina, San Diego, USA).