T47D-MTVL cells were fixed using 1% formaldehyde, harvested and sonicated using a Diagenode Bioruptor to generate chromatin fragments between 200 and 500 bp. To perform the chromatin immunoprecipitation, 30 µg of chromatin was immunoprecipitated overnight using the indicated antibody. Rabbit IgG (Santa Cruz Biothechnology) was used as a control for nonspecific interaction of DNA. Input was prepared with 10% of the chromatin material used for an immunoprecipitation. Immunocomplexes were recovered using Protein A magnetic beads from Millipore. Beads with bound antibody/protein/DNA complexes were washed, decross-linked at 65ºC overnight and immunoprecipitated DNA was recovered using the IPure Kit from Diagenode. DNA libraries were prepared for sequencing using standard Illumina protocols