Enroth et al. BMC Cancer 2011, 11:450 http://www.biomedcentral.com/1471-2407/11/450 colon mucosa samples from 24 and 9 different CRC patients corresponded to GSE10950 and GSE5364 data- sets, respectively. HT29 expression data (GSM277543) was originally generated in parallel with the tissue sam- ples from GSE10950 dataset. Additional material Additional file 1: Marked genes: Lists of genes enriched with H3K4me3 or H3K27me3 in patient material or cell line. Additional file 2: Supplementary Material: 6 figures and 2 tables. List of abbreviations CRC: colorectal cancer; H3K4me3: histone H3 lysine 4 trimethylation; H3K27me3: histone H3 lysine 27 trimethylation; ChIP: chromatin immunoprecipitation; ChIP-chip: chromatin immunoprecipitation and microarray hybridization. Acknowledgements AR-I was partially supported by Signe and Olof Wallenius Foundation and Lars Hiertas Foundation. JK was supported by the Polish Ministry of Science and Higher Education, grant number N301 239536 and Uppsala University. CW was supported by the Swedish Research Council for Science and Technology, the Cancer Foundation, the Markus Borgström Foundation and Uppsala University (ALF). Author details 1The Linnaeus Centre for Bioinformatics, Department of Cell and Molecular Biology, Science for Life Laboratory, Biomedical Center, Uppsala University, Box 598, SE-75124 Uppsala, Sweden. 2Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Rudbeck Laboratory, Uppsala University, SE-75185 Uppsala, Sweden. 3Department of Surgical Sciences, Uppsala University, SE-75185 Uppsala, Sweden. 4Interdisciplinary Centre for Mathematical and Computational Modelling, Warsaw University, PL-02-106 Warszawa, Poland. 5Current address: Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Rudbeck Laboratory, Uppsala University, SE-75185 Uppsala, Sweden. 6Current address: Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, California 94305, USA. 7Current address: Department of Biology, Bioinformatics Centre, University of Copenhagen, Ole Maaloes Vej 5 DK-2200, Copenhagen N, Denmark. Authors’ contributions SE and ARI analysed the data, SE and RA designed and implemented the bioinformatics pipeline, ARI and OW prepared and performed the ChIP, AW and LP prepared the patient material, JK supervised the bioinformatics development. CW conceived and designed the study. All authors read and approved the final manuscript. Received: 15 February 2011 Accepted: 19 October 2011 Published: 19 October 2011 References 1. Baylin SB, Ohm JE: Epigenetic gene silencing in cancer - a mechanism for early oncogenic pathway addiction? Nature reviews 2006, 6(2):107-116. 2. Esteller M: Epigenetics provides a new generation of oncogenes and tumour-suppressor genes. British journal of cancer 2006, 94(2):179-183. 3. Esteller M: Cancer epigenomics: DNA methylomes and histone- modification maps. Nat Rev Genet 2007, 8(4):286-298. 4. 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