RELB and mantle cell lymphoma: In addition to our observations, RelB activation was found to occur in a subset of poor prognosis diffuse large B-cell lymphoma patients [29]; studies in Hodgkin lymphoma (HL) confirmed that knockdown or chemical inhibition of RelB resulted in a dramatic loss of viability of HL cell lines [30] and increased non-canonical NF-κB signalling occured in ibrutinib-resistant MCL cases [11].