1601469-08-2Relevant academic research and scientific papers
A biphenyl inhibitor of eIF4E targeting an internal binding site enables the design of cell-permeable PROTAC-degraders
Fischer, Patrick D.,Papadopoulos, Evangelos,Dempersmier, Jon M.,Wang, Zi-Fu,Nowak, Rados?aw P.,Donovan, Katherine A.,Kalabathula, Joann,Gorgulla, Christoph,Junghanns, Pierre P.M.,Kabha, Eihab,Dimitrakakis, Nikolaos,Petrov, Ognyan I.,Mitsiades, Constantine,Ducho, Christian,Gelev, Vladimir,Fischer, Eric S.,Wagner, Gerhard,Arthanari, Haribabu
, (2021)
The eukaryotic translation initiation factor 4E (eIF4E) is the master regulator of cap-dependent protein synthesis. Overexpression of eIF4E is implicated in diseases such as cancer, where dysregulation of oncogenic protein translation is frequently observed. eIF4E has been an attractive target for cancer treatment. Here we report a high-resolution X-ray crystal structure of eIF4E in complex with a novel inhibitor (i4EG-BiP) that targets an internal binding site, in contrast to the previously described inhibitor, 4EGI-1, which binds to the surface. We demonstrate that i4EG-BiP is able to displace the scaffold protein eIF4G and inhibit the proliferation of cancer cells. We provide insights into how i4EG-BiP is able to inhibit cap-dependent translation by increasing the eIF4E-4E-BP1 interaction while diminishing the interaction of eIF4E with eIF4G. Leveraging structural details, we designed proteolysis targeted chimeras (PROTACs) derived from 4EGI-1 and i4EG-BiP and characterized these on biochemical and cellular levels. We were able to design PROTACs capable of binding eIF4E and successfully engaging Cereblon, which targets proteins for proteolysis. However, these initial PROTACs did not successfully stimulate degradation of eIF4E, possibly due to competitive effects from 4E-BP1 binding. Our results highlight challenges of targeted proteasomal degradation of eIF4E that must be addressed by future efforts.
Structure-activity relationship study of 4EGI-1, small molecule eIF4E/eIF4G protein-protein interaction inhibitors
Takrouri, Khuloud,Chen, Ting,Papadopoulos, Evangelos,Sahoo, Rupam,Kabha, Eihab,Chen, Han,Cantel, Sonia,Wagner, Gerhard,Halperin, Jose A.,Aktas, Bertal H.,Chorev, Michael
, p. 361 - 377 (2014/04/17)
Abstract Protein-protein interactions are critical for regulating the activity of translation initiation factors and multitude of other cellular process, and form the largest block of untapped albeit most challenging targets for drug development. 4EGI-1, (E/Z)-2-(2-(4-(3,4-dichlorophenyl)thiazol-2-yl) hydrazono)-3-(2-nitrophenyl)propanoic acid, is a hit compound discovered in a screening campaign of small molecule libraries as an inhibitor of translation initiation factors eIF4E and eIF4G protein-protein interaction; it inhibits translation initiation in vitro and in vivo. A series of 4EGI-1-derived thiazol-2-yl hydrazones have been designed and synthesized in order to delineate the structural latitude and improve its binding affinity to eIF4E, and increase its potency in inhibiting the eIF4E/eIF4G interaction. Probing a wide range of substituents on both phenyl rings comprising the 3-phenylpropionic acid and 4-phenylthiazolidine moieties in the context of both E- and Z-isomers of 4EGI-1 led to analogs with enhanced binding affinity and translation initiation inhibitory activities.
