BI-3812
Probe criteria
| Inhibitor/agonist potency: goal is < 100 nM (IC50, Kd) | Surpasses criterion: IC50 ≤ 3 nM (BCL6:BCOR ULight TR-FRET; With affinities of approximately 3 nM, the assay wall of this assay is reached, limiting the accuracy.) SPR (BCL6): KD = 2.569 ± 0.08 nM (Ontario institute for cancer research) |
| Selectivity within target family: > 30-fold | Chemoaffinity pulldown with an immobilized BI-3802 analog: BCL6 was confirmed as the major target and no other BTB/POZ domain containing proteins were identified.SPR: BCL6B KD = 3.683 ± 0.602 μM, no binding for ZBTB32, ZBTB17, ZBTB16 (Ontario institute for cancer research) |
| Selectivity outside target family | Eurofins SafteyScreen (44 targets) at 10 µM [% ctrl]: CHRM1 (15), CHRM2 (13), others > 50 Invitrogen kinase panel (54 kinases) at 1µM with no hits <75% control.Clean PDSP scan (43 targets at 10 µM) except for CHRM4 (Ki = 878.13 nM). |
| On target cell activity for cell-based targets: goal is < 1 µM IC50/EC50 | Surpasses criterion: IC50 =40 nM (BCL6::NCOR LUMIER)DC50 ≈ 200 nM (BCL6 protein degradation in SU-DHL-4 cells) ==> inactive |
| Control compound (100 times less potent than the probe) | BI-5273: IC50 = 10162 nM (BCL6::BCOR ULight TR-FRET); inactive in BCL6 protein degradation in SU-DHL-4 cellsSPR: BCL6 (KD = 1.409 ± 0.45 μM), no binding for BCL6B, ZBTB32, ZBTB17, ZBTB16 (Ontario institute for cancer research)Eurofins SafteyScreen (44 targets) at 10 µM: no hits < 40% control |