The nuclear export protein XPO1-from biology to targeted therapy

Exportin 1 (XPO1), also known as chromosome region maintenance protein 1, plays a crucial role in maintaining cellular homeostasis via the regulated export of a range of cargoes, including proteins and several classes of RNAs, from the nucleus to the cytoplasm. Dysregulation of this protein plays a pivotal role in the development of various solid and haematological malignancies. Furthermore, XPO1 is associated with resistance to several standard-of-care therapies, including chemotherapies and targeted therapies, making it an attractive target of novel cancer therapies. Over the years, a number of selective inhibitors of nuclear export have been developed. However, only selinexor has been clinically validated. The novel mechanism of action of XPO1 inhibitors implies a different toxicity profile to that of other agents and has proved challenging in certain settings. Nonetheless, data from clinical trials have led to the approval of the XPO1 inhibitor selinexor (plus dexamethasone) as a fifth-line therapy for patients with multiple myeloma and as a monotherapy for patients with relapsed and/or refractory diffuse large B cell lymphoma. In this Review, we summarize the progress and challenges in the development of nuclear export inhibitors and discuss the potential of emerging combination therapies and biomarkers of response. Nuclear import and export proteins, such as exportin 1(XPO1), regulate the transport of proteins and other molecules into and out of the nucleus, including several tumour suppressor proteins. The dysregulation of nuclear export can be observed in several types of haematological and solid tumours, providing a rationale for a novel form of targeted therapy. In this Review, the authors describe the development of XPO1 inhibitors, from basic research to clinical approval.

Automated summary

XPO1 plays a crucial role in cellular homeostasis and cancer development, with its inhibitor selinexor clinically validated and approved for multiple myeloma and diffuse large B cell lymphoma treatment.