Inhibition of proliferation and survival of diffuse large B-cell lymphoma cells by a small-molecule inhibitor of the ubiquitin-conjugating enzyme Ubc13-Uev1A.

ABSTRACT: Diffuse large B-cell lymphoma (DLBCL), the most common type of non-Hodgkin lymphoma, remains a partially curable disease. Genetic alterations affecting components of NF-?B signaling pathways occur frequently in DLBCL. Almost all activated B cell-like (ABC) DLBCL, which is the least curable group among the 3 major subtypes of this malignancy, and a substantial fraction of germinal center B cell-like (GCB) DLBCL exhibit constitutive NF-?B pathway activity. It has been demonstrated that ABC-DLBCL cells require such activity for proliferation and survival. Therefore, inhibition of NF-?B activation in DLBCL may provide an efficient and targeted therapy. In screening for small-molecule compounds that may inhibit NF-?B activation in DLBCL cells, we identified a compound, NSC697923, which inhibits the activity of the ubiquitin-conjugating (E2) enzyme Ubc13-Uev1A. NSC697923 impedes the formation of the Ubc13 and ubiquitin thioester conjugate and suppresses constitutive NF-?B activity in ABC-DLBCL cells. Importantly, NSC697923 inhibits the proliferation and survival of ABC-DLBCL cells and GCB-DLBCL cells, suggesting the Ubc13-Uev1A may be crucial for DLBCL growth. Consistently, knockdown of Ubc13 expression also inhibited DLBCL cell survival. The results of the present study indicate that Ubc13-Uev1A may represent a potential therapeutic target in DLBCL. In addition, compound NSC697923 may be exploited for the development of DLBCL therapeutic agents.

SUBMITTER: Pulvino M 

PROVIDER: S-EPMC3429308 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature