RNA-seq profiling of SEM B-ALL cells silenced for KMT2A::AFF1 fusion circular RNA.

Recently, KMT2A::AFF1 fusion circular RNAs (f-circRNAs) were identified by bioinformatics in B-ALL; however, their contribution to leukemia has not been explored. In this context, we identified a novel recurrent back-splicing junction joining the AFF1 exon 8 to KMT2A exon 2 (AK_8_2), which was recurrent in t(4;11)-positive B-ALL cell lines as well as in pediatric and adult B-ALL patients.

To investigate its functional role, we performed the total RNA-seq profiling of SEM B-ALL cells harboring the t(4;11) translocation and knocked-down for AK_8_2 f-circRNA, thus identifying a set of up-regulated genes potentially relevant for cell metabolism and leukemogenesis.