The relationship of REL proto-oncogene to pathobiology and chemoresistance in follicular and transformed follicular lymphoma

•REL is frequently amplified in follicular lymphoma (FL) cases.•No mutations of REL were detected in its conserved coding sequences in FL cases.•Ectopic REL marginally promotes growth in an FL cell line in low-serum medium.•REL-high tFL cases are associated with genotoxicity-induced NF-κB pathway.•REL expression levels may predict response to chemotheraphy in FL and/or tFL cases.