CREBBP and B-cell chronic lymphocytic leukemia: Indeed, killing of CD19+ cells in the blood of CLL patients by obinutuzumab was found to directly correlate with surface levels of CD20 (Patz et al., 2011) and downregulation of CD20 through depletion of the transcriptional coactivator CREB binding protein led to reductions in obinutuzumab mediated killing (Scialdone et al., 2019).