Aberrant hyperediting of myeloma transcriptome by ADAR1 confers oncogenicity and is a marker of poor prognosis

We constructed strand-specific cDNA libraries of 23 total RNA samples (human cell lines and patient samples) and sequenced the libraries using Hiseq 4000 platform. More than 80 millions of mappable reads for each sample have been obtained. The clinical importance of RNA editing in myeloma disease pathogenesis was elucidated by comparing the global editing events in the primary clinical samples. RNA was extracted from the plasma cells of the healthy volunteers and myeloma patients (from different disease stages) and paired end, 100bp RNA sequencing was conducted. Only high confidence editing events (at least 20 reads count and more than 10% absolute editing frequency) were considered for downstream analyses. Functional importance of ADAR1 in RNA editing was investigated by looking at the effects of differential ADAR1 expression after knocking down and overexpressing ADAR1 in myeloma cell lines. Likewise, only high confidence editing events were included into the analyses.