We conducted our studies on crystals of the BTB domain of the transcriptional repressor and therapeutic cancer target B-cell lymphoma 6 (BCL6) (Cerchietti et al., 2010 ▸), complexed to nine inhibitors from our drug discovery programme (Bellenie et al., 2020 ▸; Pierrat et al., 2022 ▸), which share the same core scaffold but have different halogen substitution patterns [Fig. 1 ▸(a)]. Here, BCL6 is linked to cancer.