Secondary mutations as a mechanism of cisplatin resistance in BRCA2-mutated cancers


Ovarian carcinomas with mutations in the tumour suppressor BRCA2 are particularly sensitive to platinum compounds1. However, such carcinomas ultimately develop cisplatin resistance. The mechanism of that resistance is largely unknown2. Here we show that acquired resistance to cisplatin can be mediated by secondary intragenic mutations in BRCA2 that restore the wild-type BRCA2 reading frame. First, in a cisplatin-resistant BRCA2-mutated breast-cancer cell line, HCC1428, a secondary genetic change in BRCA2 rescued BRCA2 function. Second, cisplatin selection of a BRCA2-mutated pancreatic cancer cell line, Capan-1 (refs 3, 4), led to five different secondary mutations that restored the wild-type BRCA2 reading frame. All clones with secondary mutations were resistant both to cisplatin and to a poly(ADP-ribose) polymerase (PARP) inhibitor (AG14361). Finally, we evaluated recurrent cancers from patients whose primary BRCA2-mutated ovarian carcinomas were treated with cisplatin. The recurrent tumour that acquired cisplatin resistance had undergone reversion of its BRCA2 mutation. Our results suggest that secondary mutations that restore the wild-type BRCA2 reading frame may be a major clinical mediator of acquired resistance to platinum-based chemotherapy.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1: HCC1428 is a cisplatin-resistant breast-cancer cell line with a secondary BRCA2 mutation.
Figure 2: Secondary genetic changes in mutated BRCA2 in cisplatin-resistant clones of a pancreatic cancer cell line, Capan-1.
Figure 3: Functional analyses of the restored BRCA2 proteins.
Figure 4: Genetic reversion of BRCA2 in platinum-resistant recurrent BRCA2 -mutated ovarian cancer.


  1. 1

    Yuan, S. S. et al. BRCA2 is required for ionizing radiation-induced assembly of Rad51 complex in vivo. Cancer Res. 59, 3547–3551 (1999)

    CAS  PubMed  Google Scholar 

  2. 2

    Agarwal, R. & Kaye, S. B. Ovarian cancer: strategies for overcoming resistance to chemotherapy. Nature Rev. Cancer 3, 502–516 (2003)

    CAS  Article  Google Scholar 

  3. 3

    Goggins, M. et al. Germline BRCA2 gene mutations in patients with apparently sporadic pancreatic carcinomas. Cancer Res. 56, 5360–5364 (1996)

    CAS  PubMed  Google Scholar 

  4. 4

    Abbott, D. W., Freeman, M. L. & Holt, J. T. Double-strand break repair deficiency and radiation sensitivity in BRCA2 mutant cancer cells. J. Natl Cancer Inst. 90, 978–985 (1998)

    CAS  Article  Google Scholar 

  5. 5

    Li, A. J. & Karlan, B. Y. Genetic factors in ovarian carcinoma. Curr. Oncol. Rep. 3, 27–32 (2001)

    CAS  Article  Google Scholar 

  6. 6

    van Asperen, C. J. et al. Cancer risks in BRCA2 families: estimates for sites other than breast and ovary. J. Med. Genet. 42, 711–719 (2005)

    CAS  Article  Google Scholar 

  7. 7

    Howlett, N. G. et al. Biallelic inactivation of BRCA2 in Fanconi anemia. Science 297, 606–609 (2002)

    CAS  Article  ADS  Google Scholar 

  8. 8

    Moynahan, M. E., Pierce, A. J. & Jasin, M. BRCA2 is required for homology-directed repair of chromosomal breaks. Mol. Cell 7, 263–272 (2001)

    CAS  Article  Google Scholar 

  9. 9

    Neuhausen, S. L. & Marshall, C. J. Loss of heterozygosity in familial tumors from three BRCA1-linked kindreds. Cancer Res. 54, 6069–6072 (1994)

    CAS  PubMed  Google Scholar 

  10. 10

    Collins, N. et al. Consistent loss of the wild type allele in breast cancers from a family linked to the BRCA2 gene on chromosome 13q12–13. Oncogene 10, 1673–1675 (1995)

    CAS  PubMed  Google Scholar 

  11. 11

    Gudmundsson, J. et al. Different tumor types from BRCA2 carriers show wild-type chromosome deletions on 13q12–q13. Cancer Res. 55, 4830–4832 (1995)

    CAS  PubMed  Google Scholar 

  12. 12

    Bhattacharyya, A., Ear, U. S., Koller, B. H., Weichselbaum, R. R. & Bishop, D. K. The breast cancer susceptibility gene BRCA1 is required for subnuclear assembly of Rad51 and survival following treatment with the DNA cross-linking agent cisplatin. J. Biol. Chem. 275, 23899–23903 (2000)

    CAS  Article  Google Scholar 

  13. 13

    Tutt, A. N. et al. Exploiting the DNA repair defect in BRCA mutant cells in the design of new therapeutic strategies for cancer. Cold Spring Harb. Symp. Quant. Biol. 70, 139–148 (2005)

    CAS  Article  Google Scholar 

  14. 14

    Foulkes, W. D. BRCA1 and BRCA2: chemosensitivity, treatment outcomes and prognosis. Fam. Cancer 5, 135–142 (2006)

    CAS  Article  Google Scholar 

  15. 15

    Boyd, J. et al. Clinicopathologic features of BRCA-linked and sporadic ovarian cancer. J. Am. Med. Assoc. 283, 2260–2265 (2000)

    CAS  Article  Google Scholar 

  16. 16

    Hirschhorn, R. In vivo reversion to normal of inherited mutations in humans. J. Med. Genet. 40, 721–728 (2003)

    CAS  Article  Google Scholar 

  17. 17

    Hamanoue, S. et al. Myeloid lineage-selective growth of revertant cells in Fanconi anaemia. Br. J. Haematol. 132, 630–635 (2006)

    CAS  Article  Google Scholar 

  18. 18

    Xia, B. et al. Fanconi anaemia is associated with a defect in the BRCA2 partner PALB2. Nature Genet. 39, 159–161 (2007)

    CAS  Article  Google Scholar 

  19. 19

    Gazdar, A. F. et al. Characterization of paired tumor and non-tumor cell lines established from patients with breast cancer. Int. J. Cancer 78, 766–774 (1998)

    CAS  Article  Google Scholar 

  20. 20

    Neuhausen, S. et al. Recurrent BRCA2 6174delT mutations in Ashkenazi Jewish women affected by breast cancer. Nature Genet. 13, 126–128 (1996)

    CAS  Article  Google Scholar 

  21. 21

    Saeki, H. et al. Suppression of the DNA repair defects of BRCA2-deficient cells with heterologous protein fusions. Proc. Natl Acad. Sci. USA 103, 8768–8773 (2006)

    CAS  Article  ADS  Google Scholar 

  22. 22

    Wu, K. et al. Functional evaluation and cancer risk assessment of BRCA2 unclassified variants. Cancer Res. 65, 417–426 (2005)

    CAS  PubMed  Google Scholar 

  23. 23

    Farmer, H. et al. Targeting the DNA repair defect in BRCA mutant cells as a therapeutic strategy. Nature 434, 917–921 (2005)

    CAS  Article  ADS  Google Scholar 

  24. 24

    Bryant, H. E. et al. Specific killing of BRCA2-deficient tumours with inhibitors of poly(ADP-ribose) polymerase. Nature 434, 913–917 (2005)

    CAS  Article  ADS  Google Scholar 

  25. 25

    Jacquemont, C. & Taniguchi, T. Proteasome function is required for DNA damage response and fanconi anemia pathway activation. Cancer Res. 67, 7395–7405 (2007)

    CAS  Article  Google Scholar 

  26. 26

    Tutt, A. et al. Mutation in Brca2 stimulates error-prone homology-directed repair of DNA double-strand breaks occurring between repeated sequences. EMBO J. 20, 4704–4716 (2001)

    CAS  Article  Google Scholar 

  27. 27

    Hilton, J. L. et al. Inactivation of BRCA1 and BRCA2 in ovarian cancer. J. Natl. Cancer Inst. 94, 1396–1406 (2002)

    CAS  Article  Google Scholar 

  28. 28

    Ikeda, H. et al. Genetic reversion in an acute myelogenous leukemia cell line from a Fanconi anemia patient with biallelic mutations in BRCA2. Cancer Res. 63, 2688–2694 (2003)

    CAS  PubMed  Google Scholar 

  29. 29

    Wiegant, W. W., Overmeer, R. M., Godthelp, B. C., van Buul, P. P. & Zdzienicka, M. Z. Chinese hamster cell mutant, V-C8, a model for analysis of Brca2 function. Mutat. Res. 600, 79–88 (2006)

    CAS  Article  Google Scholar 

  30. 30

    Gorre, M. E. et al. Clinical resistance to STI-571 cancer therapy caused by BCR-ABL gene mutation or amplification. Science 293, 876–880 (2001)

    CAS  Article  Google Scholar 

  31. 31

    Taniguchi, T. et al. Disruption of the Fanconi anemia–BRCA pathway in cisplatin-sensitive ovarian tumors. Nature Med. 9, 568–574 (2003)

    CAS  Article  Google Scholar 

  32. 32

    Garcia-Higuera, I. et al. Interaction of the Fanconi anemia proteins and BRCA1 in a common pathway. Mol. Cell 7, 249–262 (2001)

    CAS  Article  Google Scholar 

  33. 33

    Taniguchi, T. et al. Convergence of the Fanconi anemia and ataxia telangiectasia signaling pathways. Cell 109, 459–472 (2002)

    CAS  Article  Google Scholar 

  34. 34

    Chirnomas, D. et al. Chemosensitization to cisplatin by inhibitors of the Fanconi anemia/BRCA pathway. Mol. Cancer Ther. 5, 952–961 (2006)

    CAS  Article  Google Scholar 

  35. 35

    Naf, D., Kupfer, G. M., Suliman, A., Lambert, K. & D’Andrea, A. D. Functional activity of the fanconi anemia protein FAA requires FAC binding and nuclear localization. Mol. Cell. Biol. 18, 5952–5960 (1998)

    CAS  Article  Google Scholar 

  36. 36

    Skalitzky, D. J. et al. Tricyclic benzimidazoles as potent poly(ADP-ribose) polymerase-1 inhibitors. J. Med. Chem. 46, 210–213 (2003)

    CAS  Article  Google Scholar 

  37. 37

    Yamashita, T., Barber, D. L., Zhu, Y., Wu, N. & D’Andrea, A. D. The Fanconi anemia polypeptide FACC is localized to the cytoplasm. Proc. Natl Acad. Sci. USA 91, 6712–6716 (1994)

    CAS  Article  ADS  Google Scholar 

  38. 38

    Bruun, D. et al. siRNA depletion of BRCA1, but not BRCA2, causes increased genome instability in Fanconi anemia cells. DNA Repair 2, 1007–1013 (2003)

    CAS  Article  Google Scholar 

  39. 39

    Trask, B. J. in Genome Analysis: A Laboratory Manual (eds Birren, B. et al.), vol. 4 303–413 (Cold Spring Harbor Laboratory Press, New York, 1999)

    Google Scholar 

Download references


We thank M.C. King and C. W. Drescher for discussions, B. Trask for overseeing the FISH analyses in her laboratory and for comments on the manuscript, J.W. Huang for comments on the manuscript, and M. Hoatlin and K. Polyak for reagents. We thank Pfizer for AG14361. We thank the Pacific Ovarian Cancer Research Consortium (supported by a Specialized Program of Research Excellence in Ovarian Cancer) for clinical specimens. This work was supported by grants from the National Institutes of Health/National Cancer Institute (to T.T. and E.M.S.), the Searle Scholars Program, the V Foundation and the Hartwell Innovation Fund (to T.T.), the L&S Milken Foundation (to B.Y.K.), the American Cancer Society California Division-Early Detection Professorship (to B.Y.K.), start-up funds from the Fred Hutchinson Cancer Research Center (to T.T.) and a gift from the Yvonne Betson Trust (to E.M.S.).

Author Contributions W.S. performed most of the experiments. E.M.S., B.Y.K. and N.U. provided clinical samples and expertise on ovarian cancer. E.M.S. performed laser capture microdissection and DNA extractions. M.K.A., D.J.F. and F.J.C. performed homologous recombination assays. J.H. sequenced BRCA2 in HCC1428. C.F. performed FISH analysis. E.V. performed the siRNA experiments shown in Fig. 1f, g. C.J. performed the PARP inhibitor sensitivity assays in Fig. 3c. T.T., W.S. and E.M.S. wrote the manuscript.

Author information



Corresponding author

Correspondence to Toshiyasu Taniguchi.

Supplementary information

Supplementary Information

The file contains Supplementary Figures S1-S9 with Legends and Supplementary Tables S1-S5. (PDF 4082 kb)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Sakai, W., Swisher, E., Karlan, B. et al. Secondary mutations as a mechanism of cisplatin resistance in BRCA2-mutated cancers. Nature 451, 1116–1120 (2008).

Download citation

Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing