Abstract 105: A rational approach for the discovery of inhibitors of NSD2 for the treatment of cancer

Multiple myeloma (MM) is a plasma cell malignancy which accounts for approximately 10% of hematologic malignancies. Despite the introduction of new therapeutic agents, MM remains incurable and nearly all patients ultimately relapse. About 20% of MM are due to a chromosomal translocation t(4;14) leading to overexpression of the NSD2 histone methyltransferase. NSD2 catalyzes dimethylation of lysine 36 on histone H3 (H3K36me2) and is associated with transcriptionally active regions. Several studies have shown that in MM harboring the translocation t(4;14), oncogenic programming is dependent on the methyltransferase activity of NSD2. In addition, the NSD2 overactivity is also observed in prostate and lung cancers. Thus, NSD2 is a potential target for cancers, for which no selective drug is available to date. Using the AlphaLisa™ technology, we screened 240,000 compounds coming from our proprietary library. The assay is based on the detection of H3K36me2 on nucleosome by a specific antibody. False positives hits were removed by a technological counterscreen, and compounds with redox activity were excluded. This strategy allowed us to identify about 200 compounds. To focus on the most interesting ones, an orthogonal counterscreen based on 3 H SAM incorporation is being completed. In parallel to the biochemical screening, we are developing secondary cellular assays based on the H3K36me2 methylation and proliferation to further confirm hit activity. To our knowledge, no NSD2 inhibitor have been identified to date despite several screening effort performed by other groups. Our library has already produced new chemical starting points for other KMTs, and we believe that our hits could be promising starting points to generate potent and selective NSD2 inhibitors. Citation Format: Claudia Fromond, Xavier Espanel, Anne Soude, Laurent Chene, Philippe Masson, Benaissa Boubia, Christian Montalbetti, Pierre Broqua. A rational approach for the discovery of inhibitors of NSD2 for the treatment of cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 105. doi:10.1158/1538-7445.AM2015-105