Table 1 Guidelines for a high-quality chemical probe, and evaluation of IMP-1710 and LDN-57444 against these criteria (✓ meets requirement, ✗ does not meet requirement, − unknown as to whether meets requirement).
From: UCHL1 as a novel target in breast cancer: emerging insights from cell and chemical biology
Parameter | Value | Typical assay/analysis format | IMP-1710 | LDN-57444 |
|---|---|---|---|---|
Potency | IC50/Kd < 100 nM | In vitro biochemical assay | ✓ | ✗ |
Selectivity over next most engaged target(s) | >30 fold | In vitro biochemical assay, proteomics analysis | ✓ | ✗ |
On-target cellular activity | IC50 or EC50 < 1 µM | Cell-based assay | ✓ | ✗ |
Characterisation of MoA | Inhibitor, allosteric inhibitor, agonist, irreversible inhibitor, degrader, etc | Cell-based or cell-free assay in a dose-dependent manner. | Covalent, slowly reversible | Reversible |
Off-target specificity | Minimal or no off-target | In vitro biochemical assay, proteomics analysis | ✓ | − |
Chemical stability | >90% at time point >treatment time | Time course experiment | ✓ | − |
Quantitative effect | Dose-dependent labelling | Cell-based or in vitro assay | ✓ | ✗ |
Structurally related negative control available (e.g. inactive enantiomer) | In vitro potency and cell-based activity <100 times than the active probe | In vitro assay and cellular assay | ✓ | ✗ |
