Background
Post-translational modification of histones is a common mode of regulating chromatin structure and gene activity in normal tissues. In malignant cells, aberrant modifications through acetylation and methylation at the promoter regions of individual histones have been reported. Global changes in histone modification have recently been shown to be predictive of clinical outcome in prostate cancer. However, the expression and prognostic significance of modified histones in breast cancer has not been previously explored.