By contrast, in the EBV-negative DLBCL cell line MC116, IL-21 did not induce upregulation of c-Jun, cyclin D2, and cyclin E1 (Fig. 6b) and no clear increase in the levels of phosphorylated Rb protein was detected in MC116 cells (Fig. 6b). This evidence concerns the gene RB1 and diffuse large B-cell lymphoma.