Identification of LEM-14 inhibitor of the oncoprotein NSD2

The NSD family (NSD1, NSD2/MMSET/WHSC1, and NSD3/WHSC1L1) are histone lysine methyl-transferases (HMTases) essential for chromatin regulation. The NSD5 are oncoproteins, drivers of a number of tumors and are considered important drug-targets but the lack of potent and selective inhibitors hampers further therapeutic development and limits exploration of their biology. In particular, MMSET/NSD2 selective inhibition is being pursued for therapeutic interventions against multiple myeloma (MM) cases, especially in multiple myeloma t(4;14)(p16.3;q32) translocation that is associated with a significantly worse prognosis than other MM subgroups. Multiple myeloma is the second most common hematological malignancy, after non-Hodgkin lymphoma and remains an incurable malignancy. Here we report the discovery of LEM-14, an NSD2 specific inhibitor with an in vitro IC50 of 132 mu M and that is inactive against the closely related NSD1 and NSD3. LEM-14-1189, a LEM-14 derivative, differentially inhibits the NSDs with in vitro IC50 of 418 mu M (NSD1), IC50 of 111 mu M (NSD2) and IC50 of 60 mu M (NSD3). We propose LEM-14 and derivative LEM-14-1189 as tools for studying the biology of the NSD5 and constitute meaningful steps toward potent NSDs therapeutic inhibitors. (C) 2018 Elsevier Inc. All rights reserved.