XPO1 inhibitor KPT-330 disrupts the core transcriptional regulatory circuitry of dedifferentiated liposarcoma by modulating the translation process.

Dedifferentiated liposarcoma (DDLPS) is a rare and aggressive subtype of liposarcoma, driven by a core transcriptional regulatory circuitry (CRC) that sustains tumor proliferation. This malignancy poses considerable clinical challenges, marked by high postoperative recurrence and metastatic potential, alongside a lack of effective targeted therapies. In this study, we establish that KPT-330 (Selinexor), a selective inhibitor of exportin 1 (XPO1), effectively compromises DDLPS cell viability by perturbing CRC homeostasis. Mechanistically, we demonstrate that KPT-330 attenuates the cellular translation machinery in a biphasic manner: initially, it disrupts translation initiation by suppressing eukaryotic translation initiation factor 4E phosphorylation and eukaryotic translation initiation factor 4 F complex assembly; subsequently, it impedes translation elongation by inhibiting the nuclear export of ribosomal large subunit proteins. Furthermore, we identify a synergistic antitumor effect between KPT-330 and translation inhibitors, including everolimus and homoharringtonine. Notably, the disruptive impact of KPT-330 on CRC homeostasis extends to other cancer cell lineages, underscoring its broad mechanistic relevance. Collectively, our findings elucidate a novel mechanism through which KPT-330 destabilizes CRC via translational dysregulation and highlight its potential therapeutic utility in combination regimens for DDLPS.