PSMF1 and diffuse large B-cell lymphoma: In Bcl-2− DLBCL, c-Rel expression was associated with upregulation of BCL6 (required for GC formation), JUN, MYCBP2 (MYC binding protein 2, involved in Myc transcriptional activities and degradation of target proteins), cyclin genes CCNK and CCNI, LPIN1 involved in metabolism, DDR2 encoding a tyrosine kinase, and PSMF1, which inhibits the hydrolysis of protein and peptide substrates by the 20S proteasome (Fig. 3K).