Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Original Article
  • Published:

SS18-SSX fusion protein-induced Wnt/β-catenin signaling is a therapeutic target in synovial sarcoma

Abstract

Synovial sarcoma is a high-grade soft tissue malignancy characterized by a specific reciprocal translocation t(X;18), which leads to the fusion of the SS18 (SYT) gene to one of three SSX genes (SSX1, SSX2 or SSX4). The resulting chimeric SS18-SSX protein is suggested to act as an oncogenic transcriptional regulator. Despite multimodal therapeutic approaches, metastatic disease is often lethal and the development of novel targeted therapeutic strategies is required. Several expression-profiling studies identified distinct gene expression signatures, implying a consistent role of Wnt/β-catenin signaling in synovial sarcoma tumorigenesis. Here we investigate the functional and therapeutic relevance of Wnt/β-catenin pathway activation in vitro and in vivo. Immunohistochemical analyses of nuclear β-catenin and Wnt downstream targets revealed activation of canonical Wnt signaling in a significant subset of 30 primary synovial sarcoma specimens. Functional aspects of Wnt signaling including dependence of Tcf/β-catenin complex activity on the SS18-SSX fusion proteins were analyzed. Efficient SS18-SSX-dependent activation of the Tcf/β-catenin transcriptional complex was confirmed by TOPflash reporter luciferase assays and immunoblotting. In five human synovial sarcoma cell lines, inhibition of the Tcf/β-catenin protein–protein interaction significantly blocked the canonical Wnt/β-catenin signaling cascade, accompanied by the effective downregulation of Wnt targets (AXIN2, CDC25A, c-MYC, DKK1, CyclinD1 and Survivin) and the specific suppression of cell viability associated with the induction of apoptosis. In SYO-1 synovial sarcoma xenografts, administration of small molecule Tcf/β-catenin complex inhibitors significantly reduced tumor growth, associated with diminished AXIN2 protein levels. In summary, SS18-SSX-induced Wnt/β-catenin signaling appears to be of crucial biological importance in synovial sarcoma tumorigenesis and progression, representing a potential molecular target for the development of novel therapeutic strategies.

This is a preview of subscription content, access via your institution

Access options

Rent or buy this article

Prices vary by article type

from$1.95

to$39.95

Prices may be subject to local taxes which are calculated during checkout

Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7

Similar content being viewed by others

References

  1. Weiss SW, Goldblum JR, Folpe AL Enzinger and Weiss's Soft Tissue Tumors Elsevier Health Sciences 2007.

  2. Turc-Carel C, Dal Cin P, Limon J, Li F, Sandberg AA . Translocation X;18 in synovial sarcoma. Cancer Genet Cytogenet 1986; 23: 93.

    Article  CAS  Google Scholar 

  3. Clark J, Rocques PJ, Crew AJ, Gill S, Shipley J, Chan AM et al. Identification of novel genes, SYT and SSX, involved in the t(X;18)(p11.2;q11.2) translocation found in human synovial sarcoma. Nat Genet 1994; 7: 502–508.

    Article  CAS  Google Scholar 

  4. Haldar M, Randall RL, Capecchi MR . Synovial sarcoma: from genetics to genetic-based animal modeling. Clin Orthop Relat Res 2008; 466: 2156–2167.

    Article  Google Scholar 

  5. Soulez M, Saurin AJ, Freemont PS, Knight JC . SSX and the synovial-sarcoma-specific chimaeric protein SYT-SSX co-localize with the human Polycomb group complex. Oncogene 1999; 18: 2739–2746.

    Article  CAS  Google Scholar 

  6. Nagai M, Tanaka S, Tsuda M, Endo S, Kato H, Sonobe H et al. Analysis of transforming activity of human synovial sarcoma-associated chimeric protein SYT-SSX1 bound to chromatin remodeling factor hBRM/hSNF2 alpha. Proc Natl Acad Sci USA 2001; 98: 3843–3848.

    Article  CAS  Google Scholar 

  7. de Bruijn DR, Allander SV, van Dijk AH, Willemse MP, Thijssen J, van Groningen JJ et al. The synovial-sarcoma-associated SS18-SSX2 fusion protein induces epigenetic gene (de)regulation. Cancer Res 2006; 66: 9474–9482.

    Article  CAS  Google Scholar 

  8. Garcia CB, Shaffer CM, Eid JE . Genome-wide recruitment to Polycomb-modified chromatin and activity regulation of the synovial sarcoma oncogene SYT-SSX2. BMC Genomics 2012; 13: 189.

    Article  CAS  Google Scholar 

  9. Nielsen TO, West RB, Linn SC, Alter O, Knowling MA, O'Connell JX et al. Molecular characterisation of soft tissue tumours: a gene expression study. Lancet 2002; 359: 1301–1307.

    Article  CAS  Google Scholar 

  10. Nagayama S, Katagiri T, Tsunoda T, Hosaka T, Nakashima Y, Araki N et al. Genome-wide analysis of gene expression in synovial sarcomas using a cDNA microarray. Cancer Res 2002; 62: 5859–5866.

    CAS  Google Scholar 

  11. Segal NH, Pavlidis P, Antonescu CR, Maki RG, Noble WS, DeSantis D et al. Classification and subtype prediction of adult soft tissue sarcoma by functional genomics. Am J Pathol 2003; 163: 691–700.

    Article  CAS  Google Scholar 

  12. Baird K, Davis S, Antonescu CR, Harper UL, Walker RL, Chen Y et al. Gene expression profiling of human sarcomas: insights into sarcoma biology. Cancer Res 2005; 65: 9226–9235.

    Article  CAS  Google Scholar 

  13. Francis P, Namlos HM, Muller C, Eden P, Fernebro J, Berner JM et al. Diagnostic and prognostic gene expression signatures in 177 soft tissue sarcomas: hypoxia-induced transcription profile signifies metastatic potential. BMC Genomics 2007; 8: 73.

    Article  Google Scholar 

  14. Barker N, Clevers H . Mining the Wnt pathway for cancer therapeutics. Nat Rev Drug Discov 2006; 5: 997–1014.

    Article  CAS  Google Scholar 

  15. Clevers H, Nusse R . Wnt/β-Catenin Signaling and Disease. Cell 2012; 149: 1192–1205.

    Article  CAS  Google Scholar 

  16. Klaus A, Birchmeier W . Wnt signalling and its impact on development and cancer. Nat Rev Cancer 2008; 8: 387–398.

    Article  CAS  Google Scholar 

  17. Vijayakumar S, Liu G, Rus IA, Yao S, Chen Y, Akiri G et al. High-frequency canonical Wnt activation in multiple sarcoma subtypes drives proliferation through a TCF/beta-catenin target gene, CDC25A. Cancer Cell 2011; 19: 601–612.

    Article  CAS  Google Scholar 

  18. Anastas JN, Moon RT . WNT signalling pathways as therapeutic targets in cancer. Nat Rev Cancer 2013; 13: 11–26.

    Article  CAS  Google Scholar 

  19. Saito T, Oda Y, Sakamoto A, Tamiya S, Kinukawa N, Hayashi K et al. Prognostic value of the preserved expression of the E-cadherin and catenin families of adhesion molecules and of beta-catenin mutations in synovial sarcoma. J Pathol 2000; 192: 342–350.

    Article  CAS  Google Scholar 

  20. Saito T, Oda Y, Sakamoto A, Kawaguchi K, Tanaka K, Matsuda S et al. APC mutations in synovial sarcoma. J Pathol 2002; 196: 445–449.

    Article  CAS  Google Scholar 

  21. Barretina J, Taylor BS, Banerji S, Ramos AH, Lagos-Quintana M, Decarolis PL et al. Subtype-specific genomic alterations define new targets for soft-tissue sarcoma therapy. Nat Genet 2010; 42: 715–721.

    Article  CAS  Google Scholar 

  22. Lepourcelet M, Chen YN, France DS, Wang H, Crews P, Petersen F et al. Small-molecule antagonists of the oncogenic Tcf/beta-catenin protein complex. Cancer Cell 2004; 5: 91–102.

    Article  CAS  Google Scholar 

  23. Trosset JY, Dalvit C, Knapp S, Fasolini M, Veronesi M, Mantegani S et al. Inhibition of protein-protein interactions: the discovery of druglike beta-catenin inhibitors by combining virtual and biophysical screening. Proteins 2006; 64: 60–67.

    Article  CAS  Google Scholar 

  24. Zhang M, Catrow JL, Ji H . High-Throughput Selectivity Assays for Small-Molecule Inhibitors of β-Catenin/T-Cell Factor Protein–Protein Interactions. ACS Med Chem Lett 2013; 4: 306–311.

    Article  CAS  Google Scholar 

  25. Cheng GZ, Chan J, Wang Q, Zhang W, Sun CD, Wang LH . Twist transcriptionally up-regulates AKT2 in breast cancer cells leading to increased migration, invasion, and resistance to paclitaxel. Cancer Res 2007; 67: 1979–1987.

    Article  CAS  Google Scholar 

  26. Kim SY, Dunn IF, Firestein R, Gupta P, Wardwell L, Repich K et al. CK1epsilon is required for breast cancers dependent on beta-catenin activity. PLoS One 2010; 5: e8979.

    Article  Google Scholar 

  27. Liu C, Li Y, Semenov M, Han C, Baeg GH, Tan Y et al. Control of beta-catenin phosphorylation/degradation by a dual-kinase mechanism. Cell 2002; 108: 837–847.

    Article  CAS  Google Scholar 

  28. Taurin S, Sandbo N, Qin Y, Browning D, Dulin NO . Phosphorylation of beta-catenin by cyclic AMP-dependent protein kinase. J Biol Chem 2006; 281: 9971–9976.

    Article  CAS  Google Scholar 

  29. Provost E, McCabe A, Stern J, Lizardi I, D'Aquila TG, Rimm DL . Functional correlates of mutation of the Asp32 and Gly34 residues of beta-catenin. Oncogene 2005; 24: 2667–2676.

    Article  CAS  Google Scholar 

  30. Romagnolo B, Berrebi D, Saadi-Keddoucci S, Porteu A, Pichard AL, Peuchmaur M et al. Intestinal dysplasia and adenoma in transgenic mice after overexpression of an activated beta-catenin. Cancer Res 1999; 59: 3875–3879.

    CAS  Google Scholar 

  31. Pretto D, Barco R, Rivera J, Neel N, Gustavson MD, Eid JE . The synovial sarcoma translocation protein SYT-SSX2 recruits beta-catenin to the nucleus and associates with it in an active complex. Oncogene 2006; 25: 3661–3669.

    Article  CAS  Google Scholar 

  32. Lubieniecka JM, de Bruijn DR, Su L, van Dijk AH, Subramanian S, van de Rijn M et al. Histone deacetylase inhibitors reverse SS18-SSX-mediated polycomb silencing of the tumor suppressor early growth response 1 in synovial sarcoma. Cancer Res 2008; 68: 4303–4310.

    Article  CAS  Google Scholar 

  33. Gandhirajan RK, Staib PA, Minke K, Gehrke I, Plickert G, Schlosser A et al. Small molecule inhibitors of Wnt/beta-catenin/lef-1 signaling induces apoptosis in chronic lymphocytic leukemia cells in vitro and in vivo. Neoplasia 2010; 12: 326–335.

    Article  CAS  Google Scholar 

  34. Wei W, Chua MS, Grepper S, So S . Small molecule antagonists of Tcf4/beta-catenin complex inhibit the growth of HCC cells in vitro and in vivo. Int J Cancer 2010; 126: 2426–2436.

    CAS  PubMed  Google Scholar 

  35. Haldar M, Hancock JD, Coffin CM, Lessnick SL, Capecchi MR . A conditional mouse model of synovial sarcoma: insights into a myogenic origin. Cancer Cell 2007; 11: 375–388.

    Article  CAS  Google Scholar 

  36. Haldar M, Hedberg ML, Hockin MF, Capecchi MR . A CreER-based random induction strategy for modeling translocation-associated sarcomas in mice. Cancer Res 2009; 69: 3657–3664.

    Article  CAS  Google Scholar 

  37. Ng TL, Gown AM, Barry TS, Cheang MC, Chan AK, Turbin DA et al. Nuclear beta-catenin in mesenchymal tumors. Mod Pathol 2005; 18: 68–74.

    Article  CAS  Google Scholar 

  38. Hasegawa T, Yokoyama R, Matsuno Y, Shimoda T, Hirohashi S . Prognostic significance of histologic grade and nuclear expression of beta-catenin in synovial sarcoma. Hum Pathol 2001; 32: 257–263.

    Article  CAS  Google Scholar 

  39. Sato H, Hasegawa T, Kanai Y, Tsutsumi Y, Osamura Y, Abe Y et al. Expression of cadherins and their undercoat proteins (alpha-, beta-, and gamma-catenins and p120) and accumulation of beta-catenin with no gene mutations in synovial sarcoma. Virchows Arch 2001; 438: 23–30.

    Article  CAS  Google Scholar 

  40. Su L, Sampaio AV, Jones KB, Pacheco M, Goytain A, Lin S et al. Deconstruction of the SS18-SSX fusion oncoprotein complex: insights into disease etiology and therapeutics. Cancer Cell 2012; 21: 333–347.

    Article  CAS  Google Scholar 

  41. Kadoch C, Crabtree GR . Reversible disruption of mSWI/SNF (BAF) complexes by the SS18-SSX oncogenic fusion in synovial sarcoma. Cell 2013; 153: 71–85.

    Article  CAS  Google Scholar 

  42. Chen Y, Shi L, Zhang L, Li R, Liang J, Yu W et al. The molecular mechanism governing the oncogenic potential of SOX2 in breast cancer. J Biol Chem 2008; 283: 17969–17978.

    Article  CAS  Google Scholar 

  43. Naka N, Takenaka S, Araki N, Miwa T, Hashimoto N, Yoshioka K et al. Synovial sarcoma is a stem cell malignancy. Stem Cells 2010; 28: 1119–1131.

    CAS  PubMed  Google Scholar 

  44. Friedrichs N, Kriegl L, Poremba C, Schaefer KL, Gabbert HE, Shimomura A et al. Pitfalls in the detection of t(11;22) translocation by fluorescence in situ hybridization and RT-PCR: a single-blinded study. Diagn Mol Pathol 2006; 15: 83–89.

    Article  CAS  Google Scholar 

  45. Nojima T, Wang YS, Abe S, Matsuno T, Yamawaki S, Nagashima K . Morphological and cytogenetic studies of a human synovial sarcoma xenotransplanted into nude mice. Acta Pathol Jpn 1990; 40: 486–493.

    CAS  PubMed  Google Scholar 

  46. Sonobe H, Manabe Y, Furihata M, Iwata J, Oka T, Ohtsuki Y et al. Establishment and characterization of a new human synovial sarcoma cell line, HS-SY-II. Lab Invest 1992; 67: 498–505.

    CAS  PubMed  Google Scholar 

  47. Kawai A, Naito N, Yoshida A, Morimoto Y, Ouchida M, Shimizu K et al. Establishment and characterization of a biphasic synovial sarcoma cell line, SYO-1. Cancer Lett 2004; 204: 105–113.

    Article  CAS  Google Scholar 

  48. Friedrichs N, Küchler J, Endl E, Koch A, Czerwitzki J, Wurst P et al. Insulin-like growth factor-1 receptor acts as a growth regulator in synovial sarcoma. J Pathol 2008; 216: 428–439.

    Article  CAS  Google Scholar 

  49. Michels S, Trautmann M, Sievers E, Kindler D, Huss S, Renner M et al. SRC signaling is crucial in the growth of synovial sarcoma cells. Cancer Res 2013; 73: 2518–2528.

    Article  CAS  Google Scholar 

  50. Korinek V, Barker N, Morin PJ, van Wichen D, de Weger R, Kinzler KW et al. Constitutive transcriptional activation by a beta-catenin-Tcf complex in APC−/− colon carcinoma. Science 1997; 275: 1784–1787.

    Article  CAS  Google Scholar 

  51. Nguyen A, Su L, Campbell B, Poulin NM, Nielsen TO . Synergism of heat shock protein 90 and histone deacetylase inhibitors in synovial sarcoma. Sarcoma 2009; 2009: 794901.

    Article  Google Scholar 

  52. Webb JL . Enzyme and Metabolic Inhibitors. Academic Press, New York, USA, 1966.

    Google Scholar 

Download references

Acknowledgements

PKF115-584, CGP049090 and PKF118–310 were generously provided by A Wood (Novartis Pharma AG, Basel, Switzerland). This study was supported by Wilhelm Sander-Stiftung, Dr Eberhard und Hilde Rüdiger Stiftung, Deutsche Krebshilfe (KoSar sarcoma competence network), BONFOR (Medical Faculty, University Hospital Bonn, Bonn) and Fortune program (Medical Faculty, University of Cologne, Cologne).

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to W Hartmann.

Ethics declarations

Competing interests

E Wardelmann has received honoraria from speakers’ bureau of Novartis Oncology, MSD and Eisai, and is a scientific consultant/advisory board member of Novartis Oncology and MSD. The remaining authors declare no conflict of interest.

Additional information

Supplementary Information accompanies this paper on the Oncogene website

Supplementary information

Rights and permissions

Reprints and permissions

About this article

Cite this article

Trautmann, M., Sievers, E., Aretz, S. et al. SS18-SSX fusion protein-induced Wnt/β-catenin signaling is a therapeutic target in synovial sarcoma. Oncogene 33, 5006–5016 (2014). https://doi.org/10.1038/onc.2013.443

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/onc.2013.443

Keywords

This article is cited by

Search

Quick links