date of death (when the relapse data was not available). Univariate and multivariate analyses were done using Cox regression analysis. The p-values were based on the Wald test, and patients with one or more missing data were excluded. All statistical tests were two-sided at the 5% level of significance. Statistical analysis was done using the survival package (Version 2.30), in the R software (Version 2.9.1). Author contributions FS, NN, IB, ER, AL, JA, EB, SA, SE, JW performed the experiments. AF, PF, ML, JPB, CP, FB analysed the data, ECJ, JJ, CS contributed materials and analyses, DB, MC, CG designed the study and CG wrote the manuscript. Acknowledgements We thank C. Chabannon for biobanking, and F. Birg, P. Viens and L. Xerri for help and discussions. We thank D. Metzger (IGBMC, Strasbourg, France) for the gift of the ER reporter as well as C. Sardet (IGMM, Montpellier, France) for the gift of the E2F reporter. This work has been supported by Inserm, Institut Paoli-Calmettes, and grants from Ligue Nationale Contre le Cancer (Label DB), Institut National du Cancer (Recherche translationnelle 2009, DB), and Marie Curie Actions (IRG 2005, NN). FS, IB and ER have been supported by the Association pour la Recherche contre le Cancer (2009), the Algerian Government (2005–2009), and the Institut National du Cancer (2008), respectively. Supporting information is available at EMBO Medicine online. Molecular The authors declare that there is no conflict of interest. For more information Broad Institute: Gene set enrichment matrix http://www.broadinstitute.org/gsea/ BIIT research group, University of Tartu, Estonia: Multi Experiment Matrix http://biit.cs.ut.ee/mem Cancer stem cell group, Centre de Recherche en Canc´erologie de Marseille, Inserm-U891, France http://crcm.marseille.inserm.fr/spip.php?article437 References Adelaide J, Finetti P, Bekhouche I, Repellini L, Geneix J, Sircoulomb F, Charafe- Jauffret E, Cervera N, Desplans J, Parzy D et al (2007) Integrated proﬁling of basal and luminal breast cancers. Cancer Res 67: 11565-11575 Adler P, Kolde R, Kull M, Tkachenko A, Peterson H, Reimand J, Vilo J (2009) Mining for coexpression across hundreds of datasets using novel rank aggregation and visualization methods. Genome Biol 10: R139 Battaglia S, Maguire O, Campbell MJ (2010) Transcription factor co-repressors in cancer biology: roles and targeting. 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