RNA polymerase I inhibition induces terminal differentiation, growth arrest, and vulnerability to senolytics in colorectal cancer cells

Ribosomal biogenesis and protein synthesis are deregulated in most cancers, suggesting that interfering with translation machinery may hold significant therapeutic potential. Here, we show that loss of the tumor suppressor adenomatous polyposis coli (APC), which constitutes the initiating event in the adenoma carcinoma sequence for colorectal cancer (CRC), induces the expression of RNA polymerase I (RNAPOL1) transcription machinery, and subsequently upregulates ribosomal DNA (rDNA) transcription. Targeting RNAPOL1 with a specific inhibitor, CX5461, disrupts nucleolar integrity, and induces a disbalance of ribosomal proteins. Surprisingly, CX5461‐induced growth arrest is irreversible and exhibits features of senescence and terminal differentiation. Mechanistically, CX5461 promotes differentiation in an MYC‐interacting zinc‐finger protein 1 (MIZ1)‐ and retinoblastoma protein (Rb)‐dependent manner. In addition, the inhibition of RNAPOL1 renders CRC cells vulnerable towards senolytic agents. We validated this therapeutic effect of CX5461 in murine‐ and patient‐derived organoids, and in a xenograft mouse model. These results show that targeting ribosomal biogenesis together with targeting the consecutive, senescent phenotype using approved drugs is a new therapeutic approach, which can rapidly be transferred from bench to bedside.

[1]  H. He,et al.  ZNF545 loss promotes ribosome biogenesis and protein translation to initiate colorectal tumorigenesis in mice , 2021, Oncogene.

[2]  R. Pearson,et al.  Ribosomal proteins and human diseases: molecular mechanisms and targeted therapy , 2021, Signal Transduction and Targeted Therapy.

[3]  Shondra M. Pruett-Miller,et al.  The chemotherapeutic CX-5461 primarily targets TOP2B and exhibits selective activity in high-risk neuroblastoma , 2021, Nature Communications.

[4]  D. Gewirtz,et al.  Targeting tumor cell senescence and polyploidy as potential therapeutic strategies. , 2020, Seminars in cancer biology.

[5]  T. Moss,et al.  The chemotherapeutic agent CX-5461 irreversibly blocks RNA polymerase I initiation and promoter release to cause nucleolar disruption, DNA damage and cell inviability , 2020, NAR cancer.

[6]  S. Lowe,et al.  Zonation of Ribosomal DNA Transcription Defines a Stem Cell Hierarchy in Colorectal Cancer. , 2020, Cell stem cell.

[7]  A. Wiegering,et al.  Targeting Protein Synthesis in Colorectal Cancer , 2020, Cancers.

[8]  S. Elledge,et al.  The primary mechanism of cytotoxicity of the chemotherapeutic agent CX-5461 is topoisomerase II poisoning , 2020, Proceedings of the National Academy of Sciences.

[9]  A. Rosenwald,et al.  A MYC/GCN2/eIF2α negative feedback loop limits protein synthesis to prevent MYC-dependent apoptosis in colorectal cancer , 2019, Nature Cell Biology.

[10]  M. Loza,et al.  Identification and characterization of Cardiac Glycosides as senolytic compounds , 2019, Nature Communications.

[11]  L. Zender,et al.  Cardiac glycosides are broad-spectrum senolytics , 2019, Nature metabolism.

[12]  R. Pearson,et al.  First-in-Human RNA Polymerase I Transcription Inhibitor CX-5461 in Patients with Advanced Hematological Cancers: Results of a Phase I Dose Escalation Study. , 2019, Cancer discovery.

[13]  O. Sansom,et al.  Loss of BCL9/9l suppresses Wnt driven tumourigenesis in models that recapitulate human cancer , 2019, Nature Communications.

[14]  O. Dreesen,et al.  Biomarkers of Cellular Senescence and Skin Aging , 2018, Front. Genet..

[15]  M. Oeffinger,et al.  Senescence-associated ribosome biogenesis defects contributes to cell cycle arrest through the Rb pathway , 2018, Nature Cell Biology.

[16]  Andrea Sottoriva,et al.  Patient-derived organoids model treatment response of metastatic gastrointestinal cancers , 2018, Science.

[17]  A. Nebreda,et al.  TGF ‐ beta drives immune evasion in genetically reconstituted colon cancer metastasis , 2018 .

[18]  X. Zhang,et al.  Pre-45s rRNA promotes colon cancer and is associated with poor survival of CRC patients , 2017, Oncogene.

[19]  R. Lothe,et al.  Multi-omics of 34 colorectal cancer cell lines - a resource for biomedical studies , 2017, Molecular Cancer.

[20]  Jian Xian,et al.  CX-5461 is a DNA G-quadruplex stabilizer with selective lethality in BRCA1/2 deficient tumours , 2017, Nature Communications.

[21]  Davide Ruggero,et al.  New frontiers in translational control of the cancer genome , 2016, Nature Reviews Cancer.

[22]  L. Dassa,et al.  Directed elimination of senescent cells by inhibition of BCL-W and BCL-XL , 2016, Nature Communications.

[23]  R. Pearson,et al.  Combination Therapy Targeting Ribosome Biogenesis and mRNA Translation Synergistically Extends Survival in MYC-Driven Lymphoma. , 2016, Cancer discovery.

[24]  D. Baker,et al.  Cellular senescence in aging and age-related disease: from mechanisms to therapy , 2015, Nature Medicine.

[25]  T. Tokuyasu,et al.  Differential Requirements for eIF4E Dose in Normal Development and Cancer , 2015, Cell.

[26]  A. Rosenwald,et al.  A Phase I Pharmacologic Study of Necitumumab (imc-11f8), a Fully Human Igg1 Monoclonal Antibody Targeting Translation Initiation Bypasses Signaling Crosstalk Mechanisms That Maintain High Myc Levels in Colorectal Cancer , 2022 .

[27]  C. Germer,et al.  E7080 (Lenvatinib), a Multi-Targeted Tyrosine Kinase Inhibitor, Demonstrates Antitumor Activities Against Colorectal Cancer Xenografts , 2014, Neoplasia.

[28]  L. Zender,et al.  Activation and repression by oncogenic MYC shape tumour-specific gene expression profiles , 2014, Nature.

[29]  A. Iwama,et al.  Downregulation of rRNA Transcription Triggers Cell Differentiation , 2014, PloS one.

[30]  E. Hurt,et al.  Eukaryotic ribosome biogenesis at a glance , 2013, Journal of Cell Science.

[31]  R. Lothe,et al.  Epigenetic and genetic features of 24 colon cancer cell lines , 2013, Oncogenesis.

[32]  L. Zitvogel,et al.  Cardiac Glycosides Exert Anticancer Effects by Inducing Immunogenic Cell Death , 2012, Science Translational Medicine.

[33]  Steven J. M. Jones,et al.  Comprehensive molecular characterization of human colon and rectal cancer , 2012, Nature.

[34]  Carleen Cullinane,et al.  Inhibition of RNA polymerase I as a therapeutic strategy to promote cancer-specific activation of p53. , 2012, Cancer cell.

[35]  P G Pelicci,et al.  Nucleophosmin and its complex network: a possible therapeutic target in hematological diseases , 2011, Oncogene.

[36]  R. Hannan,et al.  Targeting RNA polymerase I with an oral small molecule CX-5461 inhibits ribosomal RNA synthesis and solid tumor growth. , 2011, Cancer research.

[37]  C. Lawless,et al.  Quantitative assessment of markers for cell senescence , 2010, Experimental Gerontology.

[38]  S. Formenti,et al.  Translational control in cancer , 2010, Nature Reviews Cancer.

[39]  Jun O. Liu,et al.  Digoxin and other cardiac glycosides inhibit HIF-1α synthesis and block tumor growth , 2008, Proceedings of the National Academy of Sciences.

[40]  Davide Ruggero,et al.  Suppression of Myc oncogenic activity by ribosomal protein haploinsufficiency , 2008, Nature.

[41]  P. Pelicci,et al.  A ribosomal protein L23-nucleophosmin circuit coordinates Miz1 function with cell growth , 2008, Nature Cell Biology.

[42]  M. Dai,et al.  Inhibition of c‐Myc activity by ribosomal protein L11 , 2007, The EMBO journal.

[43]  Julie A. Wilkins,et al.  Myc deletion rescues Apc deficiency in the small intestine , 2007, Nature.

[44]  B. Peterlin,et al.  Controlling the elongation phase of transcription with P-TEFb. , 2006, Molecular cell.

[45]  C. Carles,et al.  The transcriptional activity of RNA polymerase I is a key determinant for the level of all ribosome components. , 2006, Genes & development.

[46]  Carla Grandori,et al.  c-Myc binds to human ribosomal DNA and stimulates transcription of rRNA genes by RNA polymerase I , 2005, Nature Cell Biology.

[47]  P. Pandolfi,et al.  Does the ribosome translate cancer? , 2003, Nature Reviews Cancer.

[48]  Hans Clevers,et al.  The beta-catenin/TCF-4 complex imposes a crypt progenitor phenotype on colorectal cancer cells. , 2002, Cell.

[49]  N. Dubrawsky.  Cancer statistics , 1989, CA: a cancer journal for clinicians.

[50]  H. Busch,et al.  Translocation of nucleolar phosphoprotein B23 (37 kDa/pI 5.1) induced by selective inhibitors of ribosome synthesis. , 1985, Biochimica et biophysica acta.