Preclinical evaluation of Insulin-like growth factor receptor 1 (IGF1R) and Insulin Receptor (IR) as a therapeutic targets in triple negative breast cancer

PLOS ONE RESEARCH ARTICLE Preclinical evaluation of Insulin-like growth factor receptor 1 (IGF1R) and Insulin Receptor (IR) as a therapeutic targets in triple negative breast cancer a1111111111 a1111111111 a1111111111 a1111111111 a1111111111 Sandra Roche ID1*, Patricia Gaule1, Deirdre Winrow1, Nupur Mukherjee1, Fiona O’Neill1, Neil T. Conlon1, Justine Meiller1, Denis M. Collins1, Alexandra Canonici1, Mohammed Ibrahim Fawsi1, Alejandra Estepa-Fernández1, Stephen F. Madden2, John Crown1,3, Norma O’Donovan1, Alex J. Eustace1 1 National Institute for Cellular Biotechnology, Dublin City University, Glasnevin, Dublin, Ireland, 2 Data Science Centre, Royal College of Surgeons in Ireland, Dublin, Ireland, 3 Department of Medical Oncology, St Vincent’s University Hospital, Dublin, Ireland * OPEN ACCESS Citation: Roche S, Gaule P, Winrow D, Mukherjee N, O’Neill F, Conlon NT, et al. (2023) Preclinical evaluation of Insulin-like growth factor receptor 1 (IGF1R) and Insulin Receptor (IR) as a therapeutic targets in triple negative breast cancer. PLoS ONE 18(3): e0282512. https://doi.org/10.1371/journal. pone.0282512 Editor: Irina U. Agoulnik, Florida International University, UNITED STATES Received: July 26, 2022 Accepted: February 16, 2023 Published: March 15, 2023 Copyright: © 2023 Roche et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All relevant data are within the paper and its Supporting Information files. Funding: This research was supported by funding from Breast Cancer Now Starter Grant (2014NovSP452) the Health Research Board (CSA/ 2007/11), Science Foundation Ireland (08/SRC/ B1410), the Cancer Clinical Research Trust/The Caroline Foundation and the Irish Cancer Society Collaborative Cancer Research Centre Breast- Abstract Triple Negative Breast Cancer (TNBC), a subtype of breast cancer, has fewer successful therapeutic therapies than other types of breast cancer. Insulin-like growth factor receptor 1 (IGF1R) and the Insulin receptor (IR) are associated with poor outcomes in TNBC. Targeting IGF1R has failed clinically. We aimed to test if inhibiting both IR/IGF1R was a rationale therapeutic approach to treat TNBC. We showed that despite IGF1R and IR being expressed in TNBC, their expression is not associated with a negative survival outcome. Furthermore, targeting both IR/IGF1R with inhibitors in multiple TNBC cell lines did not inhibit cell growth. Linsitinib, a small molecule inhibitor of both IGF1R and IR, did not block tumour formation and had no effect on tumour growth in vivo. Cumulatively these data suggest that while IGF1R and IR are expressed in TNBC, they are not good therapeutic targets. A potential reason for the limited anti-cancer impact when IR/IGF1R was targeted may be because multiple signalling pathways are altered in TNBC. Therefore, targeting individual signalling pathways may not be sufficient to inhibit cancer growth. 1. Introduction Triple negative breast cancer (TNBC) is an aggressive disease with a high risk of recurrence, and a lack of recognised molecular targets for therapy [1]. Currently, there are a limited number of approved targeted therapies for the treatment of TNBC including PARP inhibitors (BRCA-mutated TNBCs) immunotherapy in combination with chemotherapy and the antibody drug conjugates sacituzumab govitecan and trastuzumab deruxtecan [2–4]. Therefore, there remains an urgent need to identify novel treatment options for these women. It has previously been demonstrated that women with high levels of insulin are at increased risk of developing breast cancer [5]. Early studies demonstrated that insulin receptor (IR) was both PLOS ONE | https://doi.org/10.1371/journal.pone.0282512 March 15, 2023 1 / 17 PLOS ONE Predict (CCRC13GAL). Alejandra Estepa-Fernández received support from the Erasmus+ programme of the European Union. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing interests: The authors have declared that no competing interests exist. Preclinical evaluation of IGF1R and IR as a therapeutic targets in triple negative breast cancer overexpressed and phosphorylated in breast cancers compared to normal tissue [3, 5]. The elevated phosphorylation and expression of IR were shown to correlate with increased age of the patient, increased tumour grade and to be associated with poorer overall survival [6, 7]. Insulin-like growth factor receptor 1 (IGF1R) and its signalling has been extensively studied in breast cancer and it has been implicated in resistance to hormone therapies, HER2 targeted therapies, and chemotherapy [8]. Previously, we have shown that IGF1R inhibition increases response to trastuzumab in HER2 positive breast cancer cells [9, 10]. Previous studies demonstrated that ligand bound estrogen receptor (ER) alpha is required for rapid activation of the IGF1R signalling cascade in ER positive breast cancer [11]. Further Sciacca et al., 1999, provided evidence for an autocrine IR/IGF-II signalling pathway in breast cancer cells, including TNBC cell lines, where the IR-A isoform binds IGF-II with an affinity close to that of insulin [12]. However, to date, clinical studies of IGF1R antagonism in ER positive breast cancer have been disappointing [13, 14]. Interestingly however, activated IGF1R has been associated with reduced disease free survival in TNBC [15], and has thus been assessed as a molecular therapeutic target in TNBC either alone [16] or in combination with other tyrosine kinase inhibitors; particularly those that target the PI3K/AKT pathway [17, 18]. Both the IR and the IGF1R belong to the same tyrosine kinase receptor subfamily and share structural homology in the tyrosine kinase domain [7]. Because of the inherent link between IR and IGF1R and the association with poor survival outcome in TNBC, several attempts have been made to target both IR and IGF1R to treat the disease. Firstly, Litzenburger et al., demonstrated that TNBC cell lines are sensitive to a dual IR/IGF1R small molecule inhibitor, BMS754807 [16]. More recently linsitinib (OSI-906), a novel small-molecule dual IGF1R/IR kinase inhibitor, demonstrated anti-proliferative effects in vitro and in vivo in both stem like and colorectal cancer models [19]. Linsitinib has progressed to clinical evaluation in solid tumours, but, in unselected tumours, it has shown low clinical efficacy and toxicity [20–22]. Xentuzumab (BI 836845) is a fully humanised IgG1 ligand-neutralising antibody. Whilst it does not target IR or IGF1R directly, it binds both Insulin Like Growth Factor 1 (IGF-I) and Insulin Like Growth Factor 2 (IGF-II) thus preventing activation of the receptors. Xentuzumab has been shown to reduce both IGF1R phosphorylation and cellu (...truncated)