CI-988 (PD134308) is a potent, selective and orally bioactive CCK2R (cholecystokinin 2 receptor) antagonist (inhibitor) with IC50 of 1.7 nM for mouse cortical CCK2. CI-988 is 1600-fold selective for CCK2 over the CCK1 receptor. CI-988 has anxiolytic (anti-anxiety) and anti-tumor effects.

Physicochemical Properties

Molecular Formula	C35H42N4O6
Molecular Weight	614.74
Exact Mass	614.31
CAS #	130332-27-3
PubChem CID	108187
Appearance	Typically exists as solid at room temperature
Density	1.32g/cm3
Boiling Point	949.6ºC at 760mmHg
Vapour Pressure	0mmHg at 25°C
Index of Refraction	1.647
LogP	6.031
Hydrogen Bond Donor Count	5
Hydrogen Bond Acceptor Count	6
Rotatable Bond Count	13
Heavy Atom Count	45
Complexity	1070
Defined Atom Stereocenter Count	2
SMILES	CC(CC1=CNC2=CC=CC=C21)(C(=O)NCC(C3=CC=CC=C3)NC(=O)CCC(=O)O)NC(=O)OC4C5CC6CC(C5)CC4C6
InChi Key	FVQSSYMRZKLFDR-ZABPBAJSSA-N
InChi Code	InChI=1S/C35H42N4O6/c1-35(18-26-19-36-28-10-6-5-9-27(26)28,39-34(44)45-32-24-14-21-13-22(16-24)17-25(32)15-21)33(43)37-20-29(23-7-3-2-4-8-23)38-30(40)11-12-31(41)42/h2-10,19,21-22,24-25,29,32,36H,11-18,20H2,1H3,(H,37,43)(H,38,40)(H,39,44)(H,41,42)/t21?,22?,24?,25?,29-,32?,35+/m0/s1
Chemical Name	4-[[(1R)-2-[[(2R)-2-(2-adamantyloxycarbonylamino)-3-(1H-indol-3-yl)-2-methylpropanoyl]amino]-1-phenylethyl]amino]-4-oxobutanoic acid
Synonyms	CI-988 CI988CI 988 PD-134,308PD-134308PD 134308
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)

Biological Activity

ln Vitro	CI-988 has a strong affinity (Ki of 4.5 nM) to block the specific binding of 125I-BH-CCK-8 to NCI-H727 cells. When CCK-8 is added to NCI-727 cells, it causes a rise in ROS, which CI-988 can effectively prevent. NCI-H727 cells or cells activated with CCK-8 exhibit basal growth inhibition from CI-988 (3 µM). The capacity of CCK-8 to phosphorylate ERK and raise cytosolic Ca2+ is inhibited by CI-988. [1]. In a dosage-dependent way, CI-988 prevents CCK-8 from activating EGFR in NCI-H727 cells. The effects of 0.1 µM CCK-8 on EGFR tyrosine phosphorylation were slightly and severely suppressed by CI-988 at 1 µM and 10 µM, respectively. When it comes to EGFR or ERK tyrosine phosphorylation in lung cancer, CI-988 opposes CCK-8's ability to do so [1].
ln Vivo	In xenograft model mice, CI-988 (10 mg/kg; oral; daily; for 20 days) inhibits the growth of colorectal cancer [3].
Animal Protocol	Animal/Disease Models: Nude mice were injected with LoVo cells [3] Doses: 10 mg/kg Route of Administration: po; daily; 20-day Experimental Results: inhibited the growth of xenografts by 53%.
References	[1]. CI-988 Inhibits EGFR Transactivation and Proliferation Caused by Addition of CCK/Gastrin to Lung Cancer Cells. J Mol Neurosci. 2015 Jul;56(3):663-72. [2]. Development of a class of selective cholecystokinin type B receptor antagonists having potent anxiolytic activity. Proc Natl Acad Sci U S A. 1990 Sep;87(17):6728-32. [3]. Gastrin receptor antagonist CI-988 inhibits growth of human colon cancer in vivo and in vitro. Aust N Z J Surg. 1996 Apr;66(4):235-7.

Solubility Data

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 (e.g. IP/IV/IM/SC) Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline) *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). 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)] *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. Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline) Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline) Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline) Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil) Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL 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). Oral Formulation 3: Dissolved in PEG400 Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose Oral Formulation 6: Mixing with food powders Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	1.6267 mL	8.1335 mL	16.2670 mL
	5 mM	0.3253 mL	1.6267 mL	3.2534 mL
	10 mM	0.1627 mL	0.8134 mL	1.6267 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.