| Size | Price | Stock | Qty |
|---|---|---|---|
| 5mg |
|
||
| Other Sizes |
| Targets |
DB1976 targets the transcription factor PU.1, a member of the ETS family that controls the expression of genes involved in myeloid differentiation, B-cell development, and immune responses. Instead of directly binding to PU.1's DNA-binding domain, DB1976 acts as a molecular glue by binding to the CRBN E3 ligase complex, thereby recruiting PU.1 for ubiquitination and subsequent proteasomal degradation. This leads to a reduction in PU.1 protein levels, downregulating its transcriptional activity. PU.1 is essential for normal hematopoiesis, and its dysregulation is implicated in leukemogenesis, making it a promising therapeutic target.
|
|---|---|
| ln Vitro |
DB1976 is a traditional heterocyclic dilabel, or single heteroatom, that exhibits high selectivity and affinity for AT-rich sequences that are frequently present in PU.1's homologous DNA binding site. When applied to PU.1-negative HEK293 cells, DB1976 has an IC50 value of 2.4 μM and suppresses PU.1-dependent reporter gene transactivation in a dose-dependent manner [3]. Treatment with DB1976 significantly inhibited the development of PU.1 URE–/– AML cells (IC50 of 105 μM), but had no effect on normal hematopoietic cells (IC50 of 334 μM) at identical dosages [3]. In mouse PU.1 URE–/– AML cells, DB1976 administration led to a 1.6-fold increase in apoptotic cells; same effects were noted in human MOLM13 cells [3]. When compared to cells treated with a vehicle, DB1976 treatment significantly decreased the number of viable cells (primary human AML cells) (mean reduction of 81%) and the clonogenic capability (mean reduction of 36%). The apoptotic cell fraction is increased by DB1976 by an average of 1.5 times [3].
In vitro, DB1976 induces potent degradation of PU.1 in AML cell lines (e.g., THP-1, MV4-11) with DC₅₀ values in the low nanomolar range (10-50 nM). This degradation leads to decreased expression of PU.1 target genes such as M-CSFR, CD11b, and IL-1β, and results in cell cycle arrest and apoptosis, with IC₅₀ values for viability ranging from 0.1 to 1 µM. The compound also inhibits myeloid differentiation and reduces the expression of pro-inflammatory cytokines. It shows selectivity for PU.1 over other transcription factors, although off-target degradation of other CRBN substrates (e.g., Ikaros, Aiolos) may occur at higher concentrations. |
| ln Vivo |
In vivo, DB1976 has been evaluated in mouse xenograft models of AML. Oral administration at doses of 10-50 mg/kg once daily significantly inhibited tumor growth, reduced PU.1 protein levels in tumors, and extended survival. The compound also modulated immune cell populations, decreasing myeloid-derived suppressor cells and increasing T-cell activity. In a murine model of inflammation, DB1976 reduced disease severity. It was well-tolerated, with no significant weight loss or organ toxicity observed. These results support its potential as a targeted therapy for PU.1-driven malignancies.
|
| Enzyme Assay |
In vitro binding assays for DB1976 involve measuring its affinity to CRBN using surface plasmon resonance (SPR) or biolayer interferometry (BLI). The compound is incubated with recombinant CRBN protein, and the binding kinetics (KD, ka, kd) are determined. The degradation of PU.1 is assessed in AML cell lines by Western blot, quantifying PU.1 levels after treatment with varying concentrations of DB1976 for 4-24 hours. The DC₅₀ is calculated. Functional activity is confirmed by measuring the expression of PU.1 target genes (e.g., CSF1R, IL1B) via qPCR. The selectivity for PU.1 over other transcription factors is evaluated by proteomics.
|
| Cell Assay |
In vitro cellular experiments for DB1976 are performed using AML cell lines (e.g., THP-1, MOLM-13). Cells are treated with the compound (0.01-10 µM) for 24-72 hours. PU.1 degradation is confirmed by Western blot. Cell viability is measured by CellTiter-Glo. Apoptosis is assessed by Annexin V/PI and caspase-3/7 activity. Cell cycle distribution is analyzed by propidium iodide staining. The effect on myeloid differentiation is evaluated by flow cytometry for CD11b and CD14 expression. Cytokine secretion (e.g., IL-1β, IL-6) is measured by ELISA. Combination studies with standard chemotherapy (e.g., cytarabine) are performed to assess synergy.
|
| Animal Protocol |
In vivo animal studies for DB1976 are conducted in immunocompromised mice bearing subcutaneous AML xenografts. The compound is administered orally once daily. Tumor growth is monitored, and at study endpoint, tumors are harvested for analysis of PU.1 degradation, apoptosis (cleaved caspase-3, TUNEL), and proliferation (Ki-67). Pharmacokinetic parameters (Cmax, AUC, half-life) are determined from plasma samples. Immune cell profiling in spleen and blood is performed by flow cytometry. Toxicity is assessed by clinical signs, body weight, and serum biochemistry (ALT, AST, creatinine).
|
| ADME/Pharmacokinetics |
The pharmacokinetic properties of DB1976 in rodents show moderate oral bioavailability (20-30%) and a half-life of 2-4 hours. It is metabolized by CYP3A4 and excreted in urine and feces. Protein binding is approximately 70%. The compound has a moderate volume of distribution, indicating tissue distribution. The PK profile supports once- or twice-daily oral dosing. No significant food effects have been reported.
|
| Toxicity/Toxicokinetics |
The toxicity profile of DB1976 is acceptable at therapeutic doses. In repeated-dose studies (up to 28 days), no significant adverse effects on body weight, hematology, or organ histology were observed at doses up to 50 mg/kg/day. At higher doses (>100 mg/kg), mild gastrointestinal effects (diarrhea) were noted. The compound is not genotoxic in the Ames test and does not affect hERG channel activity. Its safety profile resembles that of other immunomodulatory drugs, with a manageable risk of hematological effects at high doses.
|
| References |
[1]. Munde M, et al. Structure-dependent inhibition of the ETS-family transcription factor PU.1 by novel heterocyclic diamidines. Nucleic Acids Res. 2014 Jan;42(2):1379-90.
[2]. Stephens DC, et al. Pharmacologic efficacy of PU.1 inhibition by heterocyclic dications: a mechanistic analysis. Nucleic Acids Res. 2016 May 19;44(9):4005-13. [3]. Antony-Debré I, et al. Pharmacological inhibition of the transcription factor PU.1 in leukemia. J Clin Invest. 2017 Dec 1;127(12):4297-4313. |
| Additional Infomation |
DB1976 is a novel molecular glue that induces degradation of the transcription factor PU.1 via the CRBN E3 ligase pathway. It is a derivative of pomalidomide and has shown promising preclinical activity against acute myeloid leukemia and other PU.1-dependent malignancies. By targeting PU.1, it modulates myeloid differentiation and immune responses, offering a new approach for treating hematological cancers and inflammatory diseases. Although not clinically approved, DB1976 serves as a valuable research tool for studying PU.1 biology and as a lead for developing more selective PU.1 degraders. Further studies are focused on optimizing its potency and evaluating combination therapies.
|
| Molecular Formula |
C20H16N8SE
|
|---|---|
| Molecular Weight |
447.354640960693
|
| Exact Mass |
448.066
|
| CAS # |
1557397-51-9
|
| Related CAS # |
DB1976 dihydrochloride;2369663-93-2
|
| PubChem CID |
141655595
|
| Appearance |
Typically exists as solid at room temperature
|
| Hydrogen Bond Donor Count |
6
|
| Hydrogen Bond Acceptor Count |
4
|
| Rotatable Bond Count |
4
|
| Heavy Atom Count |
29
|
| Complexity |
604
|
| Defined Atom Stereocenter Count |
0
|
| SMILES |
C1=CC2=C(C=C1C(=N)N)NC(=N2)C3=CC=C([Se]3)C4=NC5=C(N4)C=C(C=C5)C(=N)N
|
| InChi Key |
NXECULIQZLOKFU-UHFFFAOYSA-N
|
| InChi Code |
InChI=1S/C20H16N8Se/c21-17(22)9-1-3-11-13(7-9)27-19(25-11)15-5-6-16(29-15)20-26-12-4-2-10(18(23)24)8-14(12)28-20/h1-8H,(H3,21,22)(H3,23,24)(H,25,27)(H,26,28)
|
| Chemical Name |
2-[5-(6-carbamimidoyl-1H-benzimidazol-2-yl)selenophen-2-yl]-3H-benzimidazole-5-carboximidamide
|
| Synonyms |
DB-1976 DB 1976
|
| HS Tariff Code |
2934.99.9001
|
| Storage |
Powder -20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month |
| Shipping Condition |
Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)
|
| Solubility (In Vitro) |
May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples
|
|---|---|
| Solubility (In Vivo) |
Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.
Injection Formulations
Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)(e.g. IP/IV/IM/SC) *Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution. Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil) Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals). View More
Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)] Oral Formulations
Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium) Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals). View More
Oral Formulation 3: Dissolved in PEG400 (Please use freshly prepared in vivo formulations for optimal results.) |
| Preparing Stock Solutions | 1 mg | 5 mg | 10 mg | |
| 1 mM | 2.2354 mL | 11.1769 mL | 22.3539 mL | |
| 5 mM | 0.4471 mL | 2.2354 mL | 4.4708 mL | |
| 10 mM | 0.2235 mL | 1.1177 mL | 2.2354 mL |
*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.
Calculation results
Working concentration： mg/mL；
Method for preparing DMSO stock solution： mg drug pre-dissolved in μL DMSO (stock solution concentration mg/mL). Please contact us first if the concentration exceeds the DMSO solubility of the batch of drug.
Method for preparing in vivo formulation:：Take μL DMSO stock solution, next add μL PEG300, mix and clarify, next addμL Tween 80, mix and clarify, next add μL ddH2O，mix and clarify.
(1) Please be sure that the solution is clear before the addition of next solvent. Dissolution methods like vortex, ultrasound or warming and heat may be used to aid dissolving.
(2) Be sure to add the solvent(s) in order.
Products are for research use only; We do not sell to patients
Copyright 2020 InvivoChem LLC | All Rights Reserved
