Prolyl-tRNA synthetase as a novel therapeutic target in multiple myeloma

Multiple myeloma (MM) is a plasma cell malignancy characterised by aberrant production of immunoglobulins requiring survival mechanisms to adapt to proteotoxic stress. We here show that glutamyl-prolyl-tRNA synthetase (GluProRS) inhibition constitutes a novel therapeutic target. Genomic data suggest...

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Bibliographic Details
Main Authors: Kurata, K, James-Bott, A, Tye, MA, Yamamoto, L, Samur, MK, Tai, Y-T, Dunford, J, Johansson, C, Senbabaoglu, F, Philpott, M, Palmer, C, Ramasamy, K, Gooding, S, Smilova, M, Gaeta, G, Guo, M, Christianson, JC, Payne, NC, Singh, K, Karagoz, K, Stokes, ME, Ortiz, M, Hagner, P, Thakurta, A, Cribbs, A, Mazitschek, R, Hideshima, T, Anderson, KC, Oppermann, U
Format: Journal article
Language:English
Published: Springer Nature 2023
Description
Summary:Multiple myeloma (MM) is a plasma cell malignancy characterised by aberrant production of immunoglobulins requiring survival mechanisms to adapt to proteotoxic stress. We here show that glutamyl-prolyl-tRNA synthetase (GluProRS) inhibition constitutes a novel therapeutic target. Genomic data suggest that GluProRS promotes disease progression and is associated with poor prognosis, while downregulation in MM cells triggers apoptosis. We developed NCP26, a novel ATP-competitive ProRS inhibitor that demonstrates significant anti-tumour activity in multiple in vitro and in vivo systems and overcomes metabolic adaptation observed with other inhibitor chemotypes. We demonstrate a complex phenotypic response involving protein quality control mechanisms that centers around the ribosome as an integrating hub. Using systems approaches, we identified multiple downregulated proline-rich motif-containing proteins as downstream effectors. These include CD138, transcription factors such as MYC, and transcription factor 3 (TCF3), which we establish as a novel determinant in MM pathobiology through functional and genomic validation. Our preclinical data therefore provide evidence that blockade of prolyl-aminoacylation evokes a complex pro-apoptotic response beyond the canonical integrated stress response and establish a framework for its evaluation in a clinical setting.