Targeted CRM1-inhibition perturbs leukemogenic NUP214 fusion proteins and exerts anti-cancer effects in leukemia cell lines with <i>NUP214</i> rearrangements
Adélia Mendes, Ramona Jühlen, Valérie Martinelli, Birthe Fahrenkrog
Abstract
// Adélia Mendes 1 , Ramona Jühlen 1 , 2 , Valérie Martinelli 1 and Birthe Fahrenkrog 1 1 Institute of Molecular Biology and Medicine, Université Libre de Bruxelles, Charleroi 6041, Belgium 2 Institute of Biochemistry and Molecular Cell Biology, RWTH Aachen University, Aachen 52074, Germany Correspondence to: Birthe Fahrenkrog, email: [email protected] Keywords: CRM1; NUP214; leukemia; nuclear export; nucleoporin Received: May 23, 2020     Accepted: August 01, 2020     Published: September 08, 2020 ABSTRACT Chromosomal translocations fusing the locus of nucleoporin NUP214 each with the proto-oncogenes SET and DEK are recurrent in, largely intractable, acute leukemias. The molecular basis underlying the pathogenesis of SET-NUP214 and DEK-NUP214 are still poorly understood, but both chimeras inhibit protein nuclear export mediated by the β-karyopherin CRM1. In this report, we show that SET-NUP214 and DEK-NUP214 both disturb the localization of proteins essential for nucleocytoplasmic transport, in particular for CRM1-mediated protein export. Endogenous and exogenous SET-NUP214 and DEK-NUP214 form nuclear bodies. These nuclear bodies disperse upon targeted inhibition of CRM1 and the two fusion proteins re-localize throughout the nucleoplasm. Moreover, SET-NUP214 and DEK-NUP214 nuclear bodies reestablish shortly after removal of CRM1 inhibitors. Likewise, cell viability, metabolism, and proliferation of leukemia cell lines harboring SET-NUP214 and DEK-NUP214 are compromised by CRM1 inhibition, which is even sustained after clearance from CRM1 antagonists. Our results indicate CRM1 as a possible therapeutic target in NUP214-related leukemia. This is especially important, since no specific or targeted treatment options for NUP214 driven leukemia are available yet.