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The enigmatic helicase DHX9 and its association with the hallmarks of cancer

    Chloe Gulliver

    Institute of Cardiovascular & Medical Science, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK

    ,
    Ralf Hoffmann

    Institute of Cardiovascular & Medical Science, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK

    Philips Research Europe, High Tech Campus, Eindhoven, The Netherlands

    &
    George S Baillie

    *Author for correspondence: Tel.: +44 141 330 1662;

    E-mail Address: George.Baillie@glasgow.ac.uk

    Institute of Cardiovascular & Medical Science, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK

    Published Online:https://doi.org/10.2144/fsoa-2020-0140

    Much interest has been expended lately in characterizing the association between DExH-Box helicase 9 (DHX9) dysregulation and malignant development, however, the enigmatic nature of DHX9 has caused conflict as to whether it regularly functions as an oncogene or tumor suppressor. The impact of DHX9 on malignancy appears to be cell-type specific, dependent upon the availability of binding partners and activation of inter-connected signaling pathways. Realization of DHX9’s pivotal role in the development of several hallmarks of cancer has boosted the enzyme's potential as a cancer biomarker and therapeutic target, opening up novel avenues for exploring DHX9 in precision medicine applications. Our review discusses the ascribed functions of DHX9 in cancer, explores its enigmatic nature and potential as an antineoplastic target.

    Lay abstract

    DExH-Box helicase 9 (DHX9) is an enzyme with multiple important functions in cells, therefore, its deregulated activity can cause alterations in cellular growth and subsequent formation of tumors. In particular, irregular DHX9 activity is attributed to the development of several hallmarks of cancer, however, it can have both pro- and anti-cancer effects, thus leading to conflicting views on DHX9's role in cancer development. The diverse implications of DHX9 in malignancy exposes the protein as a potential marker for cancer detection and intervention. Our review discusses the vast array of DHX9’s functions in cancer development, and its potential as a target for cancer treatment.

    Papers of special note have been highlighted as: • of interest; •• of considerable interest

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