LNCaP cells treated with ecalcitol (0.1–10 nM) for 48 hours showed a dose-dependent reduction in Pim-1 protein and mRNA expression. Moreover, ecalcitol (0.1–10 nM; 48 hours) dose-dependently lowers ETV1 expression levels. LNCaP and HL-60 cell growth is inhibited by ecalcitol (10–14 days) with ED50 values of 4.0 nM and 0.28 nM, respectively [1].

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For 42 days, ecalcitol (1.3 mg/kg; intraperitoneally; three times weekly) suppresses the growth of human malignancies that respond to androgens in vivo [1]. Pharmacokinetic analyses demonstrate that inecalcitol's axial half-life (using the C57Bl/6J mouse model;

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n a phase I multicenter trial in metastatic castration-resistant prostate cancer (mCRPC) patients, Inecalcitol was combined with docetaxel (75 mg/m² every 3 weeks) and oral prednisone (5 mg twice a day).
PSA response: 85% (40/47) of evaluable patients achieved ≥30% PSA decline within 3 months of treatment initiation; 76.6% (36/47) achieved ≥50% PSA decline at any time during the study; 36.2% (17/47) achieved ≥90% PSA decline at any time during the study.
Median time to first ≥30% PSA decline was 40 days (95% CI, 22-42, range 16-83+ days). Median time to first ≥50% PSA decline was 48 days (95% CI, 41-62, range 16-133+ days).
Median time to PSA progression was 169 days. [3]

Western Blot Analysis [1]
Cell Types: LNCaP Cell
Tested Concentrations: 0.1 nM [1]. , 1 nM, 10 nM
Incubation Duration: 48 hrs (hours)
Experimental Results: Caused a dose-dependent decrease in the expression of Pim-1 protein and mRNA.

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Animal/Disease Models: Male BNX nu/nu (nude) mice (8 weeks old) injected with LNCaP cells [1]
Doses: 1.3 mg/kg
Route of Administration: ip; 1.3 mg/kg; ip) and 18.3 minutes in mice [1]. 3 times a week; 42 days
Experimental Results: Inhibits the growth of androgen-responsive prostate cancer in the body.

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Dose-limiting toxicity (DLT) was grade 3 hypercalcemia. DLT occurred in 2 of 4 patients receiving 8,000 μg/day after 1 and 2 weeks of Inecalcitol. Calcemia normalized a few days after interruption of Inecalcitol. The maximum tolerated dose (MTD) was 4,000 μg daily.
Hypercalcemia: 31.5% (17/54) of patients experienced grade 1 hypercalcemia (mostly just above upper limit of normal, short duration 1-2 days); grade 2 and grade 3 hypercalcemia occurred in 3 patients (5.6%) each, only at the two highest dose levels (4,000 μg qd and bid). Grade 2 events normalized rapidly without corrective treatment; grade 3 returned to normal 2 days after Inecalcitol interruption.
Neutropenia grade 3-4 occurred in 80% of patients.
Other grade 3-4 events: general physical health deterioration (6%), pulmonary embolism (6%), anemia (4%), asthenia (4%), dehydration (4%), dyspnea (4%), syncope (4%), pain (4%).
Withdrawal rate due to treatment-related toxicity was 11.1% (3.7% due to Inecalcitol). At the recommended dose (4,000 μg qd), 99% of planned Inecalcitol dose and 100% of docetaxel dose were delivered.
Mean PTH levels slightly decreased; at recommended dose, PTH levels were below lower limit of normal throughout treatment. Mean osteocalcin and cross-linked C-telopeptide values decreased over time. No effect on 25(OH) vitamin D3 or phosphorus levels. [3]

[1]. Inecalcitol, an analog of 1α,25(OH)(2) D(3) , induces growth arrest of androgen-dependent prostate cancer cells. Int J Cancer. 2012 May 15;130(10):2464-73.

[2]. Interaction of two novel 14-epivitamin D3 analogs with vitamin D3 receptor-retinoid X receptor heterodimers on vitamin D3 responsive elements. J Bone Miner Res. 2001 Apr;16(4):625-38.

[3]. Phase I safety and pharmacodynamic of inecalcitol, a novel VDR agonist with docetaxel in metastatic castration-resistant prostate cancer patients. Clin Cancer Res. 2014 Sep 1;20(17):4471-7.

[4]. Inecalcitol, an analog of 1,25D3, displays enhanced antitumor activity through the induction of apoptosis in a squamous cell carcinoma model system. Cell Cycle. 2013 Mar 1;12(5):743-52.

Inecalcitol is an analogue of calcitriol and a vitamin D3 receptor (VDR) agonist with potential antitumor activity. After administration, enocarcitol targets and binds to the VDR, activating the VDR and its mediated signaling pathways. This can regulate the VDR-mediated expression of certain genes, including oncogenes, enhance cell differentiation, induce tumor cell apoptosis, and inhibit tumor cell growth. The VDR plays a central role in calcium homeostasis and the growth of certain cancer cells. Drug Indications It has been studied for the treatment of prostate cancer, psoriasis, and hyperparathyroidism. Mechanism of Action Inecalcitol is an analogue of calcitriol, the naturally occurring active metabolite of vitamin D. Calcitriol and its analogues activate the vitamin D receptor (VDR). Vitamin D plays a crucial role in regulating intestinal calcium absorption, mineral storage in bones, and renal excretion, and is effective in preventing rickets in infants. Vitamin D and calcitriol can cause hypercalcemia when taken in high doses or frequently; hypercalcemia can lead to the accumulation of calcium microcrystals, resulting in nephrotoxicity, and can also cause cardiac and muscle dysfunction by impairing contractile function. [Hybrigenics website] The mechanism of action is currently unclear, but some studies suggest that calcitriol exerts its super-agonist effect by enhancing the binding of vitamin D receptors (VDRs) to coactivators.

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Inecalcitol is a novel oral synthetic vitamin D receptor agonist with higher antiproliferative and differentiation effects and considerably less hypercalcemic effects (approximately 100-fold lower hypercalcemic activity) compared with calcitriol. Its proprietary chemical structure features a unique conformation of the carbon atom in position 14 (14-epimerization formulation). This conformation leads to different binding affinities to VDR response elements compared with calcitriol, and different gene upregulation/downregulation profiles.
The phase I study was conducted in chemotherapy-naïve metastatic castration-resistant prostate cancer (mCRPC) patients. The combination of Inecalcitol with docetaxel and prednisone showed encouraging PSA response rates. Future development will be based on molecular profiles (VDR and coregulator expression levels) to select responsive patients. [3]

C26H40O3

400.59400844574

400.297

163217-09-2

6915835

Off-white to light yellow solid powder

1.2±0.1 g/cm3

568.6±50.0 °C at 760 mmHg

244.6±24.7 °C

0.0±3.5 mmHg at 25°C

1.627

5.05

3

3

4

29

707

6

C[C@H](CC#CC(C)(C)O)[C@H]1CC[C@H]\2[C@@]1(CCC/C2=C\C=C3C[C@H](C[C@@H](C3)O)O)C

HHGRMHMXKPQNGF-WNSNRMDMSA-N

InChI=1S/C26H40O3/c1-18(7-5-13-25(2,3)29)23-11-12-24-20(8-6-14-26(23,24)4)10-9-19-15-21(27)17-22(28)16-19/h9-10,18,21-24,27-29H,6-8,11-12,14-17H2,1-4H3/b20-10+/t18-,21-,22-,23-,24-,26-/m1/s1

(1R,3R)-5-[(2E)-2-[(1R,3aR,7aR)-1-[(2R)-6-Hydroxy-6-methylhept-4-yn-2-yl]-7a-methyl-2,3,3a,5,6,7-hexahydro-1H-inden-4-ylidene]ethylidene]cyclohexane-1,3-diol

TX522 TX 522 TX-522

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: (1). This product requires protection from light (avoid light exposure) during transportation and storage.  (2). Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture.

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

DMSO : ~100 mg/mL (~249.63 mM)

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.

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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).

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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)

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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).

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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

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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.

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