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.

  • Letter
  • Published:

Identification of recurrent SMO and BRAF mutations in ameloblastomas

A Corrigendum to this article was published on 30 December 2014

This article has been updated

Abstract

Here we report the discovery of oncogenic mutations in the Hedgehog and mitogen-activated protein kinase (MAPK) pathways in over 80% of ameloblastomas, locally destructive odontogenic tumors of the jaw, by genomic analysis of archival material. Mutations in SMO (encoding Smoothened, SMO) are common in ameloblastomas of the maxilla, whereas BRAF mutations are predominant in tumors of the mandible. We show that a frequently occurring SMO alteration encoding p.Leu412Phe is an activating mutation and that its effect on Hedgehog-pathway activity can be inhibited by arsenic trioxide (ATO), an anti-leukemia drug approved by the US Food and Drug Administration (FDA) that is currently in clinical trials for its Hedgehog-inhibitory activity. In a similar manner, ameloblastoma cells harboring an activating BRAF mutation encoding p.Val600Glu are sensitive to the BRAF inhibitor vemurafenib. Our findings establish a new paradigm for the diagnostic classification and treatment of ameloblastomas.

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

Access options

Buy this article

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

Figure 1: Mutation frequency, distribution and relationship with pathological features.
Figure 2: SMO Leu412Phe activity and inhibition.
Figure 3: SMO Leu412Phe enhances ameloblast-lineage cell proliferation.
Figure 4: An ameloblastoma cell line harboring BRAF p.Val600Glu is sensitive to the BRAF inhibitor vemurafenib.

Similar content being viewed by others

Accession codes

Accessions

Protein Data Bank

Change history

  • 12 November 2014

    In the version of this article initially published, the introductory paragraph mistakenly stated that ameloblasts were "cells in the tooth roots of the upper (maxilla) and lower (mandible) jaw responsible for depositing enamel during tooth development (odontogenesis)." The correct location for human ameloblasts is in the developing tooth. Ameloblasts are the normal cell type that ameloblastoma cells resemble and are responsible for forming the enamel covering on tooth crowns. The error has been corrected in the HTML and PDF versions of the article.

References

  1. Gorlin, R.J. et al. Odontogenic tumors. Classification, histopathology, and clinical behavior in man and domesticated animals. Cancer 14, 73–101 (1961).

    Article  CAS  Google Scholar 

  2. Sweeney, R.T. et al. Desktop transcriptome sequencing from archival tissue to identify clinically relevant translocations. Am. J. Surg. Pathol. 37, 796–803 (2013).

    Article  Google Scholar 

  3. Tucker, A. et al. The cutting-edge of mammalian development; how the embryo makes teeth. Nat. Rev. Genet. 5, 499–508 (2004).

    Article  CAS  Google Scholar 

  4. Davies, H. et al. Mutations of the BRAF gene in human cancer. Nature 417, 949–954 (2002).

    Article  CAS  Google Scholar 

  5. Parada, L.F. et al. Cooperation between gene encoding p53 tumour antigen and ras in cellular transformation. Nature 312, 649–651 (1984).

    Article  CAS  Google Scholar 

  6. Li, Y. et al. Activation of FGF receptors by mutations in the transmembrane domain. Oncogene 14, 1397–1406 (1997).

    Article  CAS  Google Scholar 

  7. Xie, J. et al. Activating Smoothened mutations in sporadic basal-cell carcinoma. Nature 391, 90–92 (1998).

    Article  CAS  Google Scholar 

  8. Clark, V.E. et al. Genomic analysis of non-NF2 meningiomas reveals mutations in TRAF7, KLF4, AKT1, and SMO. Science 339, 1077–1080 (2013).

    Article  CAS  Google Scholar 

  9. Taipale, J. et al. Effects of oncogenic mutations in Smoothened and Patched can be reversed by cyclopamine. Nature 406, 1005–1009 (2000).

    Article  CAS  Google Scholar 

  10. Nakata, A. et al. Establishment and characterization of a spontaneously immortalized mouse ameloblast-lineage cell line. Biochem. Biophys. Res. Commun. 308, 834–839 (2003).

    Article  CAS  Google Scholar 

  11. Wang, C. et al. Structure of the human smoothened receptor bound to an antitumour agent. Nature 497, 338–343 (2013).

    Article  CAS  Google Scholar 

  12. Harada, H. et al. Establishment of ameloblastoma cell line, AM-1. J. Oral Pathol. Med. 27, 207–212 (1998).

    Article  CAS  Google Scholar 

  13. Søndergaard, J.N. et al. Differential sensitivity of melanoma cell lines with BRAFV600E mutation to the specific Raf inhibitor PLX4032. J. Transl. Med. 8, 39 (2010).

    Article  Google Scholar 

  14. Yang, H. et al. Antitumor activity of BRAF inhibitor vemurafenib in preclinical models of BRAF-mutant colorectal cancer. Cancer Res. 72, 779–789 (2012).

    Article  CAS  Google Scholar 

  15. Dassule, H.R. et al. Sonic hedgehog regulates growth and morphogenesis of the tooth. Development 127, 4775–4785 (2000).

    CAS  PubMed  Google Scholar 

  16. Kumamoto, H. et al. Expression of Sonic hedgehog (SHH) signaling molecules in ameloblastomas. J. Oral Pathol. Med. 33, 185–190 (2004).

    Article  CAS  Google Scholar 

  17. Heikinheimo, K. et al. Gene expression profiling of ameloblastoma and human tooth germ by means of a cDNA microarray. J. Dent. Res. 81, 525–530 (2002).

    Article  CAS  Google Scholar 

  18. Kurppa, K.J. et al. High frequency of BRAF V600E mutations in ameloblastoma. J. Pathol. 232, 492–498 (2014).

    Article  CAS  Google Scholar 

  19. Chiang, C. et al. Essential role for Sonic hedgehog during hair follicle morphogenesis. Dev. Biol. 205, 1–9 (1999).

    Article  CAS  Google Scholar 

  20. Schneider, M.R. et al. The hair follicle as a dynamic miniorgan. Curr. Biol. 19, R132–R142 (2009).

    Article  CAS  Google Scholar 

  21. Iwasaki, J.K. et al. The molecular genetics underlying basal cell carcinoma pathogenesis and links to targeted therapeutics. J. Am. Acad. Dermatol. 66, e167–e178 (2012).

    Article  CAS  Google Scholar 

  22. Fontebasso, A.M. et al. Chromatin remodeling defects in pediatric and young adult glioblastoma: a tale of a variant histone 3 tail. Brain Pathol. 23, 210–216 (2013).

    Article  CAS  Google Scholar 

  23. Kim, J. et al. Arsenic antagonizes the Hedgehog pathway by preventing ciliary accumulation and reducing stability of the Gli2 transcriptional effector. Proc. Natl. Acad. Sci. USA 107, 13432–13437 (2010).

    Article  CAS  Google Scholar 

  24. Kim, J. et al. Itraconazole and arsenic trioxide inhibit Hedgehog pathway activation and tumor growth associated with acquired resistance to smoothened antagonists. Cancer Cell 23, 23–34 (2013).

    Article  CAS  Google Scholar 

  25. Sciubba, J.J. et al. Atlas of Tumor Pathology 29, 71–84 (Armed Forces Institute of Pathology, Washington, DC, 2001).

    Google Scholar 

  26. Morlan, J.D. et al. Selective depletion of rRNA enables whole transcriptome profiling of archival fixed tissue. PLoS ONE 7, e42882 (2012).

    Article  CAS  Google Scholar 

  27. Langmead, B. et al. Fast gapped-read alignment with Bowtie 2. Nat. Methods 9, 357–359 (2012).

    Article  CAS  Google Scholar 

  28. Kim, D. et al. TopHat-Fusion: an algorithm for discovery of novel fusion transcripts. Genome Biol. 12, R72 (2011).

    Article  CAS  Google Scholar 

  29. Goya, R. et al. SNVMix: predicting single nucleotide variants from next-generation sequencing of tumors. Bioinformatics 26, 730–736 (2010).

    Article  CAS  Google Scholar 

  30. Wang, K. et al. ANNOVAR: functional annotation of genetic variants from high-throughput sequencing data. Nucleic Acids Res. 38, e164 (2010).

    Article  Google Scholar 

  31. Douville, C. et al. CRAVAT: cancer-related analysis of variants toolkit. Bioinformatics 29, 647–648 (2013).

    Article  CAS  Google Scholar 

  32. Asmann, Y.W. et al. A novel bioinformatics pipeline for identification and characterization of fusion transcripts in breast cancer and normal cell lines. Nucleic Acids Res. 39, e100 (2011).

    Article  CAS  Google Scholar 

  33. McPherson, A. et al. deFuse: an algorithm for gene fusion discovery in tumor RNA-Seq data. PLoS Comput. Biol. 7, e1001138 (2011).

    Article  CAS  Google Scholar 

  34. Iyer, M.K. et al. ChimeraScan: a tool for identifying chimeric transcription in sequencing data. Bioinformatics 27, 2903–2904 (2011).

    Article  CAS  Google Scholar 

  35. Untergasser, A. et al. Primer3—new capabilities and interfaces. Nucleic Acids Res. 40, e115 (2012).

    Article  CAS  Google Scholar 

  36. Myers, B.R. et al. Hedgehog pathway modulation by multiple lipid binding sites on the smoothened effector of signal response. Dev. Cell 26, 346–357 (2013).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We would like to thank E. Epstein for assistance. We would like to thank C. Millward, H. Kaplan and M. Labusch for histology and pathology support. We are also grateful to H. Harada (Iwate Medical University) for sharing the AM-1 cell line.

Author information

Authors and Affiliations

Authors

Contributions

R.T.S., A.C.M., J.R.P. and R.B.W. designed the study and wrote the manuscript. A.C.M., B.R.M., J.R.P. and R.B.W. designed the figures. R.T.S., X.G., J.R.P. and R.B.W. analyzed raw sequence data. J.B. and J.R.P. performed mutation validation (PCR and Sanger sequencing). B.R.M., L.N., J.B., J.R.P. and P.A.B. designed and implemented functional studies. C.D.J., J.I.O. and J.L.Z. performed targeted sequencing (TruSeq). K.A.K., K.Q. and R.J.P. performed transcriptome sequencing. S.V. performed immunohistochemistry. T.N., B.P.R. and M.L.T. provided cases for evaluation. T.S. and S.K. provided key cell line reagents.

Corresponding authors

Correspondence to Philip A Beachy, Jonathan R Pollack or Robert B West.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Integrated supplementary information

Supplementary Figure 1 Representative Sanger tracings for mutations.

(a) Tracing for representative SMO mutation encoding L412F in ameloblastoma and matched normal tissue. (b) Tracing for representative BRAF mutation encoding V600E in ameloblastoma and matched normal tissue.

Supplementary Figure 2 Expression of BRAF V600E protein.

The four cases evaluated with BRAF mutations encoding V600E show diffuse cytoplasmic staining of the epithelial component with antibody to BRAF V600E. (a) Rare, patchy staining is observed. (b–d) Darker staining, and greater cell density, is seen at the leading edge of the epithelial cell component, adjacent to the stroma. The stroma is completely negative. No staining was seen in 15 cases without the mutation encoding V600E (data not shown).

Supplementary Figure 3 Suppression of activity of SMO mutants by Ptch1 overexpression.

Relative GLI-dependent luciferase assays in ShhN-stimulated Smo–/– MEFs expressing wild-type SMO, SMO L412F, SMO W535L or GFP control, with or without engineered overexpression of Ptch1, show significant suppression of the activity of the SMO mutants by Ptch1. Each data point is based on three independent transfections (three biological replicates); error bars, s.d. Results presented for each experiment are representative of multiple independent trials.

Source data

Supplementary information

Supplementary Text and Figures

Supplementary Figures 1–3 and Supplementary Table 2 (PDF 1443 kb)

Supplementary Table 1

Clinical features and mutation status of cases. (XLSX 15 kb)

Source data

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Sweeney, R., McClary, A., Myers, B. et al. Identification of recurrent SMO and BRAF mutations in ameloblastomas. Nat Genet 46, 722–725 (2014). https://doi.org/10.1038/ng.2986

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/ng.2986

This article is cited by

Search

Quick links

Nature Briefing: Cancer

Sign up for the Nature Briefing: Cancer newsletter — what matters in cancer research, free to your inbox weekly.

Get what matters in cancer research, free to your inbox weekly. Sign up for Nature Briefing: Cancer