Histone H1 profiling in breast cancer samples

Epigenetic aberrations have been recognized as important contributors to cancer onset and development, and increasing evidence suggests that linker histone H1 variants may serve as biomarkers useful for patient stratification, as well as play an important role as drivers in cancer. Although traditionally histone H1 levels have been studied using antibody-based methods and RNA expression, these approaches suffer from limitations. Mass-spectrometry (MS)-based proteomics represents the ideal tool to accurately quantify relative changes in protein abundance within complex samples. We used a label-free quantification approach to simultaneously analyze all somatic histone H1 variants in breast cancer patient samples (different areas laser-microdissected from the same tumor sections, and triple negative samples with/without relapse 3 years after chemotherapy.