Fig. 1: RAS regulates nuclear protein export independently of PI3K and MEK signaling.
a, XPO1i (selinexor) prevented cytoplasmic export of EZH2 and XPO1. α-tubulin and lamin B1 were used as cytoplasmic and nuclear marker proteins, respectively; C, cytoplasmic; N, nuclear. b–d, siRNA knockdown of KRAS (b) or XPO1i by selinexor reduced cytoplasmic EZH2 (c) and increased DLC1 (d). Combined treatment with selinexor and KRAS siRNA did not further increase the response. e, Stable transfection of mutant KRAS-G12C in H1703 cells decreased DLC1 expression, which was not affected by MEKi (U0126-ethanol) or PI3Ki (wortmannin) but was increased by XPO1i (selinexor). Wortmannin inhibited PI3K activity (measured by pAKT-S473), and U0126-ethanol inhibited MEK activity (measured by pERK-T202/Y204) in all treated samples. f–i, In the KRAS-G12C NCI-H23 line, selinexor prevented complex formation between XPO1 and EZH2 (f and g) and between XPO1 and survivin (h), whereas complex formation was not prevented by the KRAS-G12C inhibitor sotorasib (i). Two independent experiments were performed for each image, with similar results; IB, immunoblot; IP, immunoprecipitation; WCE, whole-cell extract.
