American Association for Cancer Research
00085472can130704-sup-fig3small.pdf (109.41 kB)

Supplementary Figure 3 from Hallmarks of Aromatase Inhibitor Drug Resistance Revealed by Epigenetic Profiling in Breast Cancer

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journal contribution
posted on 2023-03-30, 21:46 authored by Maurice P.H.M. Jansen, Theo Knijnenburg, Esther A. Reijm, Iris Simon, Ron Kerkhoven, Marjolein Droog, Arno Velds, Steven van Laere, Luc Dirix, Xanthippi Alexi, John A. Foekens, Lodewyk Wessels, Sabine C. Linn, Els M.J.J. Berns, Wilbert Zwart

PDF file - 110K, Supplementary Figure S3 Principal Component Analysis for all three ChIP-seq conditions.



Aromatase inhibitors are the major first-line treatment of estrogen receptor–positive breast cancer, but resistance to treatment is common. To date, no biomarkers have been validated clinically to guide subsequent therapy in these patients. In this study, we mapped the genome-wide chromatin-binding profiles of estrogen receptor α (ERα), along with the epigenetic modifications H3K4me3 and H3K27me3, that are responsible for determining gene transcription (n = 12). Differential binding patterns of ERα, H3K4me3, and H3K27me3 were enriched between patients with good or poor outcomes after aromatase inhibition. ERα and H3K27me3 patterns were validated in an additional independent set of breast cancer cases (n = 10). We coupled these patterns to array-based proximal gene expression and progression-free survival data derived from a further independent cohort of 72 aromatase inhibitor–treated patients. Through this approach, we determined that the ERα and H3K27me3 profiles predicted the treatment outcomes for first-line aromatase inhibitors. In contrast, the H3K4me3 pattern identified was not similarly informative. The classification potential of these genes was only partially preserved in a cohort of 101 patients who received first-line tamoxifen treatment, suggesting some treatment selectivity in patient classification. Cancer Res; 73(22); 6632–41. ©2013 AACR.