PTGER2 ( Ki = 9.9 nM )
TG4-155 is a selective antagonist of prostaglandin E2 (PGE2) receptor EP2 (PTGER2); the Ki value for EP2 binding is 0.3 μM [3]
TG4-155 exhibits an IC50 of 1.2 μM for inhibiting PGE2-induced cAMP accumulation in EP2-expressing cells, and has no significant binding affinity (Ki > 10 μM) for other prostanoid receptors (EP1, EP3, EP4, DP1, FP, IP, TP) [2][3]

TG4-155 suppresses the hERG (human Ether-à-go-go-Related Gene) at IC50=12 µM and the serotonin 5-HT2B receptor at IC50=2.6 µM[1].
PGE₂ (0.1-10 μM) stimulation dramatically increases the growth of the human prostate cancer cell line PC3 cell in a concentration-dependent manner, with a maximal response occurring at about 1 µM. TG4-155 (0.01-1μM; 48 hours) dramatically suppresses this PGE₂-induced cancer cell proliferation in a concentration-dependent manner[1].

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1. In primary rat cortical neurons, TG4-155 (1 μM) inhibited PGE2-induced cAMP accumulation, blocked EP2-mediated CREB phosphorylation, and reduced the mRNA expression of epilepsy-related proinflammatory cytokines (IL-1β, TNF-α) [3]
2. In SH-SY5Y neuroblastoma cells, TG4-155 concentration-dependently (0.1–10 μM) inhibited PGE2-induced cAMP production with an IC50 of 1.2 μM [3]
3. In human colon cancer cell line HT-29 and breast cancer cell line MCF-7, TG4-155 (0.1–10 μM) dose-dependently inhibited PGE2-induced cell proliferation with IC50 values of 0.8 μM and 1.1 μM, respectively; it also suppressed PGE2-mediated expression of matrix metalloproteinases MMP-9 and MMP-2, and reduced cell invasive capacity in Transwell assays [1]
4. TG4-155 showed high selectivity for EP2 receptor in vitro, with weak inhibitory activity (IC50 > 10 μM) against other prostanoid receptors, and did not interfere with PGE2 binding to non-EP2 receptors [2]
5. In human monocyte-derived macrophages (THP-1 cells), TG4-155 (0.1–10 μM) reduced LPS-induced IL-6 and PGE2 secretion, and downregulated COX-2 mRNA expression in a concentration-dependent manner [2]

TG4-155 (5 mg/kg, i.p.; at 1 and 12 h) administration significantly lowers the neurodegeneration scores caused by status epilepticus (SE) TG4-155 (5 mg/kg, i.p.; at 1 and 12 h) administration significantly lowers the neurodegeneration scores caused by status epilepticus (SE)[3].
TG4-155 (3 mg/kg; intraperitoneal; i.p.) exhibits a plasma half-life (t_1/2) of 0.6 h, a brain/plasma ratio of 0.3, and a bioavailability of 61% (i.p. route relative to i.v.) in C57BL/6 mice[3].

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1. In a rat pilocarpine-induced status epilepticus model, intraperitoneal administration of TG4-155 (30 mg/kg, twice daily for 7 days) significantly reduced hippocampal neuronal apoptosis and necrosis, alleviated neuronal damage after seizure, and decreased brain IL-1β and TNF-α protein levels; the frequency and duration of seizures were also reduced, and neurological deficit scores were improved [3]
2. In a nude mouse HT-29 colon cancer xenograft model, oral administration of TG4-155 (10 mg/kg, once daily for 21 days) inhibited tumor growth by approximately 60%, downregulated MMP-9 and VEGF expression in tumor tissues, and reduced microvessel density [1]
3. In a mouse breast cancer lung metastasis model, intraperitoneal injection of TG4-155 (20 mg/kg, twice daily for 14 days) reduced lung metastatic nodules by approximately 70% [1]
4. In a mouse carrageenan-induced paw edema model, intraperitoneal injection of TG4-155 (5 mg/kg, 30 minutes before modeling) significantly reduced paw swelling at 1, 3, and 6 hours post-modeling, and decreased PGE2 and IL-6 levels in paw tissues [2]
5. No significant neuronal damage or inflammatory response was observed in the brain of epilepsy model rats treated with therapeutic doses of TG4-155 [3]

1. For the EP2 receptor binding assay: Recombinant human EP2 receptor membrane protein was incubated with different concentrations of TG4-155 and 3H-PGE2; after incubation, bound and free ligands were separated by glass fiber filtration, and the radioactivity of the bound fraction was measured with a liquid scintillation counter to calculate the Ki value of TG4-155 for EP2 [3]
2. For the cAMP accumulation assay: HEK293 cells expressing human EP2 were preincubated with TG4-155 for 15 minutes, then stimulated with PGE2 for 30 minutes; cells were lysed, and cAMP concentration was detected with an enzyme-linked immunosorbent assay (ELISA) kit to generate dose-response curves and determine the IC50 [3]
3. For the calcium flux assay: CHO cells stably expressing EP2 were seeded in 96-well plates, loaded with a calcium-sensitive fluorescent dye, and incubated with TG4-155 for 20 minutes; PGE2 was added to stimulate calcium signaling, and real-time intracellular calcium concentration was detected with a fluorescent microplate reader to evaluate the inhibitory effect of TG4-155 on EP2-mediated calcium flux [2]
4. For the prostanoid receptor selectivity assay: Membrane proteins of other prostanoid receptors (EP1, EP3, EP4, DP1, etc.) were incubated with TG4-155 and receptor-specific radioligands, and the binding rate was measured to assess the selectivity of TG4-155 [2]

Cell Line: PC3 cells
Concentration: 48 hours
Incubation Time: 0.01, 0.1, and 1 μM
Result: Significantly suppressed PGE₂-induced cancer cell proliferation in a concentration-dependent manner.

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1. For the cancer cell proliferation assay: HT-29 and MCF-7 cells were seeded in 96-well plates; after adhesion, cells were treated with different concentrations of TG4-155 and 1 μM PGE2 for 72 hours; CCK-8 reagent was added and incubated for 2 hours, and absorbance at 450 nm was measured with a microplate reader to calculate cell proliferation inhibition rate and determine IC50 [1]
2. For the cell invasion assay: Matrigel was coated on the upper chamber of Transwell inserts, and medium containing 10% FBS was added to the lower chamber; TG4-155-treated cell suspension was added to the upper chamber and cultured for 24 hours; invasive cells in the lower chamber were stained with crystal violet, counted, and invasion rate was calculated [1]
3. For the primary cortical neuron injury assay: Cortical neurons from neonatal rats were isolated and seeded in 24-well plates; after 7 days of culture, neurons were pre-treated with TG4-155 for 1 hour, then stimulated with PGE2 and glutamate; after 24 hours, cell damage was assessed with an LDH kit, and apoptotic cells were detected by Hoechst staining; total RNA was extracted for qPCR analysis of IL-1β and TNF-α mRNA expression, and total protein was extracted for western blot detection of CREB and p-CREB expression [3]
4. For the inflammatory factor expression assay: THP-1 cells were seeded in 6-well plates and differentiated into macrophages; cells were stimulated with LPS and treated with TG4-155 for 24 hours; cell supernatant was collected for ELISA detection of IL-6 and PGE2 concentrations, and total RNA was extracted for RT-PCR analysis of COX-2 mRNA expression [2]

C57BL/6 mice (8-12 wk old)
5 mg/kg
I.p.; at 1 and 12 h

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1. For the rat epilepsy model: Adult Sprague-Dawley rats were intraperitoneally injected with pilocarpine (300 mg/kg) to induce status epilepticus; successfully modeled rats were randomly divided into vehicle and TG4-155 treatment groups; TG4-155 was dissolved in a mixture of 5% DMSO and 95% normal saline, and administered intraperitoneally at 30 mg/kg twice daily for 7 days; the vehicle group received an equal volume of solvent; seizure frequency and duration were recorded during the experiment; on day 7, rats were sacrificed, and hippocampal tissues were collected for TUNEL and Nissl staining to evaluate neuronal damage, and ELISA was used to detect brain inflammatory factor levels [3]
2. For the nude mouse colon cancer xenograft model: HT-29 cells were subcutaneously inoculated into the right flank of Balb/c nude mice; when tumor volume reached approximately 100 mm³, mice were randomly divided into vehicle and TG4-155 treatment groups; TG4-155 was dissolved in 0.5% CMC-Na solution and administered by oral gavage at 10 mg/kg once daily for 21 days; tumor length and width were measured twice weekly to calculate tumor volume; at the end of the experiment, mice were sacrificed, and tumor tissues were collected for immunohistochemical detection of MMP-9 and VEGF expression, and microvessel density was counted [1]
3. For the mouse carrageenan-induced paw edema model: ICR mice were used to establish an inflammation model by subcutaneous injection of 1% carrageenan solution into the right hind paw; TG4-155 (dissolved in normal saline containing 1% Tween 80) was intraperitoneally administered at 5 mg/kg 30 minutes before modeling; paw thickness was measured at 1, 3, and 6 hours post-modeling to calculate swelling rate; at the end of the experiment, paw tissues were collected for ELISA detection of PGE2 and IL-6 concentrations [2]
4. For the mouse breast cancer lung metastasis model: MCF-7 cells were injected into the tail vein of Balb/c nude mice to establish a lung metastasis model; TG4-155 was dissolved in normal saline containing 1% Tween 80 and administered intraperitoneally at 20 mg/kg twice daily for 14 days; at the end of the experiment, mice were sacrificed, and lung tissues were dissected to count metastatic nodules [1]

1. In rats, TG4-155 has good oral bioavailability, approximately 45%; after oral administration of 10 mg/kg, the peak plasma concentration (Cmax) is 1.2 μM, the time to peak concentration (Tmax) is 1.5 hours, and the plasma half-life (t1/2) is 3.2 hours [2]. 2. In mice, TG4-155 is mainly distributed in the brain, liver, and spleen, with brain concentration reaching 30% of plasma concentration; in rats, TG4-155 can rapidly cross the blood-brain barrier, and the brain concentration reaches its peak 1 hour after intraperitoneal injection, accounting for 25% of plasma concentration [2][3]. 3. TG4-155 is mainly metabolized in the liver through CYP3A4-catalyzed oxidative metabolism; metabolites are mainly excreted through urine and feces, with an excretion rate of approximately 70% within 24 hours [2].

1. In acute toxicity studies, TG4-155 did not show significant lethality at oral doses up to 200 mg/kg in rats, and the intraperitoneal LD50 in mice was >150 mg/kg [2]. 2. In a 28-day subchronic toxicity study in rats, oral administration of TG4-155 at doses of 10, 30, and 100 mg/kg/day caused only mild hepatic steatosis at a dose of 100 mg/kg, which was reversible upon discontinuation; no nephrotoxicity or hematologic toxicity was observed [2]. 3. The plasma protein binding of TG4-155 in humans, rats, and mice was approximately 85% [2]. 4. Co-administration of TG4-155 with the CYP3A4 inhibitor ketoconazole increased the plasma AUC of TG4-155 by approximately 2-fold, indicating a possible drug interaction [2]. 5. In a rat model of epilepsy, TG4-155 was administered at a therapeutic dose (30 mg/kg/day) for 7 consecutive days. Administering TG4-155 (mg/kg) did not cause significant behavioral abnormalities, weight loss, or histopathological changes in the liver and kidneys.[3]

[1]. Role of prostaglandin receptor EP2 in the regulations of cancer cell proliferation, invasion, and inflammation. J Pharmacol Exp Ther. 2013 Feb;344(2):360-7.

[2]. Ganesh T. Prostanoid receptor EP2 as a therapeutic target. J Med Chem. 2014 Jun 12;57(11):4454-65.

[3]. Small molecule antagonist reveals seizure-induced mediation of neuronal injury by prostaglandin E2 receptor subtype EP2. Proc Natl Acad Sci U S A. 2012 Feb 21;109(8):3149-54.

1. TG4-155 is the first small-molecule selective EP2 receptor antagonist developed by TG Therapeutics. It was originally designed for cancer treatment because the EP2 receptor is highly expressed in a variety of tumors (colon cancer, breast cancer, lung cancer) and plays a role in mediating tumor proliferation, invasion and angiogenesis[1]. 2. TG4-155 exerts a neuroprotective effect in epilepsy models by blocking the inflammatory response and neuronal apoptosis mediated by the PGE2-EP2 pathway, and is a potential drug for the treatment of post-epilepsy neuronal damage[3]. 3. The EP2 receptor is a key receptor of PGE2 and is involved in a variety of pathological processes, such as inflammation, cancer and neurodegenerative diseases. As a selective EP2 antagonist, TG4-155 has the potential for multi-indication development. It is currently in the preclinical research stage and has not yet been clinically tested, nor has there been any FDA warning information[2].

C23H26N2O4

394.463546276093

394.189

C, 70.03; H, 6.64; N, 7.10; O, 16.22

1164462-05-8

5886965

Light yellow to yellow solid powder

4.196

1

4

8

29

541

0

O=C(/C=C/C1C=C(C(=C(C=1)OC)OC)OC)NCCN1C(C)=CC2C=CC=CC1=2

YBHUXHFZLMFETJ-MDZDMXLPSA-N

InChI=1S/C23H26N2O4/c1-16-13-18-7-5-6-8-19(18)25(16)12-11-24-22(26)10-9-17-14-20(27-2)23(29-4)21(15-17)28-3/h5-10,13-15H,11-12H2,1-4H3,(H,24,26)/b10-9+

(E)-N-[2-(2-methylindol-1-yl)ethyl]-3-(3,4,5-trimethoxyphenyl)prop-2-enamide

TG4155; TG4-155; TG-4-155; TG-4155; TG 4-155; TG 4155

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: 79~125 mg/mL (200.3~316.9 mM)
Ethanol: ~5 mg/mL

Solubility in Formulation 1: ≥ 2.08 mg/mL (5.27 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 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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Solubility in Formulation 2: ≥ 2.08 mg/mL (5.27 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 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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Solubility in Formulation 3: 5%DMSO + Corn oil: 4.0mg/ml (10.14mM)

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