Doxycycline treatment resulted in an increase in the neddylated (slower-migrating) forms of Cullin-1 and Cullin-2 in the DLBCL cells (Figure 6E and Supplementary Figure 6), indicating that doxycycline inhibits CSN5 activity in DLBCL cells. This evidence concerns the gene COPS5 and diffuse large B-cell lymphoma.