P-glycoprotein (P-gp)

In P-glycoprotein-active cell lines, zosuquidar (0.3 μM; 48 h) therapy increases the cytotoxicity of DNR (substrates for P-glycoproteins)[2]. Drug-sensitive and multidrug-resistant cell lines exhibit high cytotoxic concentrations when treated with zosuquidar (5–16 μM) for 72 hours[1].

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Zosuquidar is a potent inhibitor of P-glycoprotein with a Ki of 59-60 nM in cell-free assays. By binding to P-gp, zosuquidar inhibits the efflux of chemotherapeutic agents from cancer cells, thereby reversing multidrug resistance. In addition to P-gp inhibition, zosuquidar shows anti-tumor activities through triggering autophagic degradation of PD-L1, significantly inhibiting PD-L1 expression. This dual mechanism makes zosuquidar a promising agent for cancer therapy.

Treatment with zosuquidar (intraperitoneal injection; 30, 10, 3, or 1 mg/kg; once daily; 5 d) significantly lengthens life[1]. Doxorubicin combined with Zosuquidar (intraperitoneal injection; 30 mg/kg; once daily; 5 d) treatment demonstrates the potentiation[1].

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Zosuquidar shows anti-tumor activities and can be used in acute myelogenous leukemia (AML) research. It inhibits tumor growth by triggering autophagic degradation of PD-L1, significantly inhibiting PD-L1 expression. By inhibiting P-gp-mediated drug efflux, zosuquidar increases the intracellular accumulation of chemotherapeutic agents, enhancing their antitumor efficacy.

P-glycoprotein inhibition is measured using transport assays with fluorescent or radiolabeled P-gp substrates. Ki values are determined from cell-free assays. PD-L1 expression is measured by Western blot or flow cytometry to assess the compound's effects on autophagic degradation.

Cell Cytotoxicity Assay[2]
Cell Types: K562 and HL60 cells
Tested Concentrations: 0.3 μM
Incubation Duration: 48 hrs (hours)
Experimental Results: Enhanced the cytotoxicity of DNR (substrates for P-glycoproteins) in K562/DOX cells more than 45.5-fold.

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Cell Cytotoxicity Assay[1]
Cell Types: CCRF-CEM, CEM/VLB100, P388, P388/ADR, MCF7, MCF7/ADR, 2780, 2780AD, UCLA-P3, UCLA-P3.003VLB cells
Tested Concentrations: 5-16 μM
Incubation Duration: 72 hrs (hours)
Experimental Results: demonstrated IC50s of 6, 7, 15, 8, 7, 15, 11, 16, >5, >5 μM for CCRF-CEM, CEM/VLB100, P388, P388 /ADR, MCF7, MCF7/ADR, 2780, 2780AD, UCLA-P3, UCLA-P3.003VLB cells, respectively.

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Cellular potency is evaluated in P-gp-overexpressing cancer cell lines by measuring the accumulation of P-gp substrates and PD-L1 expression. Cells are treated with zosuquidar at various concentrations, and intracellular substrate accumulation is measured. PD-L1 protein levels are assessed by Western blot to confirm autophagic degradation.

Animal/Disease Models: Mice implanted with P388/ADR tumors[1]
Doses: 30, 10, 3, or 1 mg/kg
Route of Administration: intraperitoneal (ip)injection; 30, 10, 3 , or 1 mg/kg; one time/day; 5 days
Experimental Results: Exihibited a Dramatically increased survival compared to the group treated with Doxorubicin alone (P<0.001).

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Animal/Disease Models: Mice implanted with P388 or P388/ADR murine leukemia cells[1]
Doses: 30 mg/kg
Route of Administration: intraperitoneal (ip)injection; 30 mg/kg; one time/day; 5 days
Experimental Results: Observed significant antitumor activity against the MDR P388/ADR cell lines when mice were treated with a combined dose of 30 mg/kg LY335979 and 1 mg/kg Doxorubicin (P=0.1).

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Zosuquidar is evaluated in vivo in mouse xenograft models of acute myelogenous leukemia and other cancers. The compound is administered via appropriate routes at various doses, alone or in combination with chemotherapeutic agents. Tumor growth inhibition, PD-L1 expression, and drug accumulation are assessed.

Pharmacokinetic data for zosuquidar are available from preclinical studies. The compound demonstrates favorable pharmacokinetic properties for in vivo studies. Detailed PK parameters such as half-life, clearance, and bioavailability are available. Stability and solubility advice is available for formulation.

Toxicological data for zosuquidar are available from preclinical studies. The compound has been evaluated in animal models of cancer for safety and efficacy. Standard laboratory safety precautions should be observed during handling.

[1]. Reversal of P-glycoprotein-mediated multidrug resistance by a potent cyclopropyldibenzosuberane modulator, LY335979. Cancer Res. 1996 Sep 15;56(18):4171-9.

[2]. Zosuquidar restores drug sensitivity in P-glycoprotein expressing acute myeloid leukemia (AML). BMC Cancer. 2008 Feb 13;8:51.

[3]. Zosuquidar, a novel modulator of P-glycoprotein, does not improve the outcome of older patients with newly diagnosed acute myeloid leukemia: a randomized, placebo-controlled trial of the Eastern Cooperative Oncology Group 3999. Blood. 2010 Nov 18;116(20):4077-85.

LSM-5782 is a carbon polycyclic compound. Zosuquidar is an anti-tumor drug candidate under development. It is currently in Phase III clinical trials in the United States. Its mechanism of action is the inhibition of P-glycoprotein; other drugs with the same mechanism include tariquidar and laniquidar. Zosuquidar trihydrochloride is a difluorocyclopropylquinoline compound. Zosuquidar trihydrochloride binds to P-glycoprotein with high affinity and inhibits P-glycoprotein-mediated multidrug resistance (MDR). P-glycoprotein, encoded by the MDR-1 gene, is a member of the ATP-binding cassette transporter superfamily and prevents the accumulation of many naturally derived cytotoxic drugs in cells. (NCI04) Zosuquidar is a difluorocyclopropylquinoline compound. Zosuquidar binds to P-glycoprotein with high affinity and inhibits P-glycoprotein-mediated multidrug resistance (MDR). P-glycoproteins, encoded by the MDR-1 gene, are members of the ATP-binding cassette transporter superfamily and prevent the accumulation of many naturally derived cytotoxic drugs within cells. See also: Erakridar (note moved to). Drug Indications: Investigated for the treatment of leukemia (myeloid) and myelodysplastic syndromes. Mechanism of Action: P-glycoproteins are proteins that convert energy from ATP hydrolysis into structural changes in protein molecules, thereby coupling and ultimately releasing drugs from cells. If P-glycoproteins encoded by the MDR1 gene are expressed in cancer cells, they release most anti-tumor drugs from the cells, leading to drug resistance and rendering anti-tumor drugs ineffective. This protein is also expressed in normal organs unaffected by cancer (such as skin cells in the liver, small intestine, and brain blood vessels) and participates in drug transport. The compound Zosuquidar inhibits this P-glycoprotein, causing cancer cells to lose drug resistance and thus restoring the efficacy of anti-tumor drugs.

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Zosuquidar (LY335979) is a P-glycoprotein inhibitor with a Ki of 59 nM that shows anti-tumor activities and can be used in acute myelogenous leukemia (AML) research. It inhibits tumor growth by triggering autophagic degradation of PD-L1, significantly inhibiting PD-L1 expression. The compound is a potent modulator of P-gp-mediated multidrug resistance. Zosuquidar has a molecular weight of 527.60.

C32H31F2N3O2

527.6

527.238

167354-41-8

Zosuquidar trihydrochloride;167465-36-3

3036703

Off-white to light yellow solid powder

1.4±0.1 g/cm3

690.5±55.0 °C at 760 mmHg

371.4±31.5 °C

0.0±2.3 mmHg at 25°C

1.691

4.3

1

7

6

39

806

3

C1CN(CCN1C[C@H](COC2=CC=CC3=C2C=CC=N3)O)C4C5=CC=CC=C5[C@H]6[C@H](C6(F)F)C7=CC=CC=C47

IHOVFYSQUDPMCN-XAKVHENESA-N

InChI=1S/C32H31F2N3O2/c33-32(34)29-22-7-1-3-9-24(22)31(25-10-4-2-8-23(25)30(29)32)37-17-15-36(16-18-37)19-21(38)20-39-28-13-5-12-27-26(28)11-6-14-35-27/h1-14,21,29-31,38H,15-20H2/t21-,29-,30+,31?/m1/s1

(2R)-1-[4-[(2R,4S)-3,3-difluoro-11-tetracyclo[10.4.0.02,4.05,10]hexadeca-1(16),5,7,9,12,14-hexaenyl]piperazin-1-yl]-3-quinolin-5-yloxypropan-2-ol

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)

Solubility in Formulation 1: ≥ 0.83 mg/mL (1.57 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 8.3 mg/mL clear DMSO stock solution to 400 μL of PEG300 and mix evenly; then add 50 μL of Tween-80 to the above solution and mix evenly; then add 450 μL of 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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Solubility in Formulation 2: 0.83 mg/mL (1.57 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 8.3 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: ≥ 0.83 mg/mL (1.57 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 8.3 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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