HDAC1 and breast cancer: For instance, in haematological cancers, HDAC1, 2, and 6 predominate while for solid tumours, HDAC expression is variable with HDAC1-3 (gastric and colorectal cancer), HDAC1, 4–7, 10 (liver cancer) and HDAC1, 3, 6 (breast cancer) described [108].