Quinoclamine is a novel nuclear factor-κB (NF-κB) inhibitor. It suppresses NF-κB activity by inhibiting IκB-α phosphorylation and subsequent p65 translocation to the nucleus. In HepG2 cells, the IC₅₀ for NF-κB inhibition was 1.7 ± 0.1 μmol/L, and the TC₅₀ for cell viability was 3.8 ± 0.1 μmol/L. [2]

Quinoclamine induces U-937 cells to differentiate into cells resembling macrophages[1]. Quinoclamine has an IC50 of 1.7 μM and suppresses NF-κB activity in HepG2 cells[2]. Quinoclamine (1-4 μM; 30 minutes) inhibits p65 translocation and IκB-α phosphorylation, which decreases endogenous NF-κB activity in HepG2 cells[2]. In lung and breast cancer cell lines, quinocrine suppresses NF-κB activation that has been induced[2]. Quinoclamine modifies the expression levels of genes related to apoptosis or the cell cycle[2]. The expression of UDP glucuronosyltransferase genes involved in phase II drug metabolism is downregulated by quinoclinamine[2].

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In HepG2 cells, Quinoclamine (0–4 μmol/L) dose-dependently inhibited IκB-α phosphorylation and reduced nuclear p65 protein levels, indicating suppression of NF-κB activation. [2]
Quinoclamine (4 μmol/L) significantly suppressed 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced NF-κB activity in HepG2, Hep3B, Chang liver, MCF7, and A-549 cell lines (P < 0.05, P < 0.01, P < 0.001). [2]
Transcriptomic analysis (microarray) of HepG2 cells treated with quinoclamine (4 μmol/L) identified 220 up-regulated and 147 down-regulated genes in single channel hybridization, and 128 up-regulated and 175 down-regulated genes in dual channel hybridization. A total of 123 genes were commonly regulated. [2]
Gene ontology (GO) analysis showed enrichment of genes associated with cell cycle regulation. Key cell cycle-related genes regulated by quinoclamine included CCNA2 (cyclin A2, down-regulated 2.21-fold), CDKN3 (cyclin-dependent kinase inhibitor 3, down-regulated 2.86-fold), GADD45A (growth arrest and DNA-damage-inducible protein alpha, up-regulated 2.92-fold), LATS1 (large tumour suppressor homologue 1, up-regulated 3.66-fold), and STAG1 (stromal antigen 1, up-regulated 2.18-fold). [2]
Quinoclamine down-regulated all UDP glucuronosyltransferase (UGT) genes (phase II drug metabolism) in HepG2 cells. Specific UGT genes down-regulated (fold change > 2) included UGT2B7 and UGT2B11. qPCR validation confirmed down-regulation of UGT1A10, UGT2A1, UGT2B11, and UGT2B7. [2]
Phase I drug metabolism genes were variably affected: ADH7, ALDH1A2, ALDH3A2, CYP11B2, CYP1B1, and CYP4B1 were up- or down-regulated >2-fold. [2]
Quinoclamine also down-regulated BCL2L1 (Bcl-xL, fold change -2.12, P = 0.02) and CCND1 (cyclin D1, fold change -6.89, P = 0.13). [2]

Cell Viability Assay[2]
Cell Types: HepG2 cells
Tested Concentrations: 1 μM, 2 μM, 4 μM, 8 μM, 16 μM, 32 μM, 64 μM
Incubation Duration: 24 hrs (hours)
Experimental Results: Inhibited NF-κB activities in HepG2 cells.

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Western Blot Analysis[2]
Cell Types: HepG2 cells
Tested Concentrations: 0 μM, 1 μM, 2 μM, 4 μM
Incubation Duration: 30 minutes
Experimental Results: Inhibited IκB-α phosphorylation and p65 translocation in HepG2 cells.

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Cell viability was assessed using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. [2]
NF-κB activity was measured using a luciferase reporter assay. Recombinant HepG2/NF-κB cells were treated with compounds for 24 h, and luciferase activity was measured. [2]
Western blot analysis was performed to detect IκB-α phosphorylation and p65 translocation. Cells were treated with quinoclamine (0, 1, 2, 4 μmol/L), and cellular extracts were probed with anti-phospho-IκB-α, anti-IκB-α, and anti-p65 antibodies. [2]
Total RNA was extracted and used for oligonucleotide microarray analysis (single and dual channel hybridizations). Data were analyzed using the Limma package in Bioconductor. Gene ontology analysis was performed using WebGestalt, and network analysis was conducted using BiblioSphere Pathway Edition and Cytoscape. [2]
Quantitative real-time PCR (qPCR) was performed using SYBR Green PCR Master Mix to validate expression levels of selected genes. GAPDH was used as an endogenous control. [2]

However, the study analyzed gene expression of drug metabolism enzymes. Quinoclamine down-regulated all UDP glucuronosyltransferase (UGT) genes, which are involved in phase II drug metabolism (glucuronidation). This suggests that quinoclamine might interfere with drug metabolism by slowing down the excretion of drugs. [2]

In HepG2 cells, the TC₅₀ (toxic concentration for 50% cell viability) of Quinoclamine was 3.8 ± 0.1 μmol/L. [2]

[1]. Induction of differentiation of U-937 cells by 2-chloro-3-amino-1,4-naphthoquinone. Res Commun Mol Pathol Pharmacol. 1997 Aug;97(2):215-27.

[2]. Comprehensive evaluation of a novel nuclear factor-kappaB inhibitor, quinoclamine, by transcriptomic analysis. Br J Pharmacol. 2009 Jul;157(5):746-56.

Quinoclammine is a member of the 1,4-naphthoquinone class of compounds. 2-Amino-3-chloro-1,4-naphthoquinone has been reported in Shewanella oneidensis, and relevant data are available for reference.

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Quinoclamine (2-amino-3-chloro-1,4-naphthoquinone) is a chemically synthesized naphthoquinone compound identified as a novel NF-κB inhibitor. It has been previously shown to induce differentiation of human leukemia HL-60 cells via protein kinase C activation and is thought to be a potent anti-malarial agent. Its derivatives also display anti-platelet, anti-inflammatory, and anti-allergic activities. This study demonstrates that quinoclamine suppresses NF-κB activity through inhibition of IκB-α phosphorylation and p65 nuclear translocation, and regulates genes involved in cell cycle and apoptosis, suggesting anti-cancer potential. Additionally, quinoclamine down-regulates UGT genes, which may affect drug metabolism. [2]

C10H6CLNO2

207.61

207.008

2797-51-5

17748

Light yellow to orange solid powder

1.5±0.1 g/cm3

310.2±42.0 °C at 760 mmHg

198-200 °C

141.4±27.9 °C

0.0±0.7 mmHg at 25°C

1.660

1.31

1

3

0

14

335

0

OBLNWSCLAYSJJR-UHFFFAOYSA-N

InChI=1S/C10H6ClNO2/c11-7-8(12)10(14)6-4-2-1-3-5(6)9(7)13/h1-4H,12H2

2-amino-3-chloronaphthalene-1,4-dione

NSC 3910 NSC3910 NSC-3910NSC-642009 NSC642009NSC 642009

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~250 mg/mL (~1204.18 mM)

Solubility in Formulation 1: 2.08 mg/mL (10.02 mM) in 10% DMSO + 40% PEG300 +5% Tween-80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution; with sonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 + to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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 (Please use freshly prepared in vivo formulations for optimal results.)