IHC was carried out as previously described (n=3 untreated, n=5 JQ1 treated) 35 (link). Slides were submitted to antigen retrieval, and the primary antibodies listed in Table S7. Slides were incubated with secondary antibody (Dako) and DAB (Dako) and counterstained with haematoxylin solution (Sigma-Aldrich). Secondary-only control staining was done routinely. ImageJ colour deconvolution was used for quantification 35 (link).