2. Academic Validation
  3. N-acetylcysteine overcomes NF1 loss-driven resistance to PI3Kα inhibition in breast cancer

N-acetylcysteine overcomes NF1 loss-driven resistance to PI3Kα inhibition in breast cancer

  • Cell Rep Med. 2023 Apr 4;101002. doi: 10.1016/j.xcrm.2023.101002.
Priska Auf der Maur 1,  Marcel P Trefny 2,  Zora Baumann 3,  Milica Vulin 4,  Ana Luisa Correia 4,  Maren Diepenbruck 3,  Nicolas Kramer 3,  Katrin Volkmann 3,  Bogdan-Tiberius Preca 3,  Pedro Ramos 5,  Cedric Leroy 5,  Tobias Eichlisberger 6,  Katarzyna Buczak 7,  Federica Zilli 4,  Ryoko Okamoto 4,  Roland Rad 8,  Michael Rugaard Jensen 5,  Christine Fritsch 5,  Alfred Zippelius 2,  Michael B Stadler 9,  Mohamed Bentires-Alj 10
Affiliations

Affiliations

  • 1 Tumor Heterogeneity Metastasis and Resistance, Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland. Electronic address: priska.aufdermaur@unibas.ch.
  • 2 Cancer Immunology, Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland.
  • 3 Tumor Heterogeneity Metastasis and Resistance, Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland.
  • 4 Tumor Heterogeneity Metastasis and Resistance, Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland; Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.
  • 5 Oncology Research, Novartis Institutes for Biomedical Research, Basel, Switzerland.
  • 6 Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.
  • 7 Proteomics Core Facility, Biozentrum, University of Basel, Basel, Switzerland.
  • 8 Institute of Molecular Oncology and Functional Genomics, TUM School of Medicine, Technische Universität München, München, Germany; Center for Translational Cancer Research (TranslaTUM), TUM School of Medicine, Technische Universität München, München, Germany; Department of Medicine II, Klinikum rechts der Isar, Technische Universität München, München, Germany; German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany.
  • 9 Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland; Swiss Institute of Bioinformatics, Basel, Switzerland; Faculty of Science, University of Basel, Basel, Switzerland.
  • 10 Tumor Heterogeneity Metastasis and Resistance, Department of Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland; Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland. Electronic address: m.bentires-alj@unibas.ch.
PMID: 37044095 DOI: 10.1016/j.xcrm.2023.101002
Abstract

A genome-wide PiggyBac transposon-mediated screen and a resistance screen in a PIK3CAH1047R-mutated murine tumor model reveal NF1 loss in mammary tumors resistant to the phosphatidylinositol 3-kinase α (PI3Kα)-selective inhibitor alpelisib. Depletion of NF1 in PIK3CAH1047R breast Cancer cell lines and a patient-derived Organoid model shows that NF1 loss reduces sensitivity to PI3Kα inhibition and correlates with enhanced glycolysis and lower levels of Reactive Oxygen Species (ROS). Unexpectedly, the antioxidant N-acetylcysteine (NAC) sensitizes NF1 knockout cells to PI3Kα inhibition and reverts their glycolytic phenotype. Global phospho-proteomics indicates that combination with NAC enhances the inhibitory effect of alpelisib on mTOR signaling. In public datasets of human breast Cancer, we find that NF1 is frequently mutated and that such mutations are enriched in metastases, an indication for which use of PI3Kα inhibitors has been approved. Our results raise the attractive possibility of combining PI3Kα inhibition with NAC supplementation, especially in patients with drug-resistant metastases associated with NF1 loss.

Keywords

PI3K alpha inhibition; breast cancer; combination therapy; resistance; transposon screen.

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