Independent of the established IGF1 signal amplifier, fatostatin (125B11) (0.1–1 μM; 3 days) prevents androgen-free ischemia (IC50=0.1 μM). With an IC50 of 2.5 and 10 μM in Cell Helper, fatostatin directly binds SCAP and inhibits its endoplasmic reticulum-to-Golgi transit, inhibiting insulin-sensing adipogenesis in 3T3-L1 cells.

Independent of the established IGF1 signal amplifier, fatostatin (125B11) (0.1–1 μM; 3 days) prevents androgen-free ischemia (IC50=0.1 μM). With an IC50 of 2.5 and 10 μM in Cell Helper, fatostatin directly binds SCAP and inhibits its endoplasmic reticulum-to-Golgi transit, inhibiting insulin-sensing adipogenesis in 3T3-L1 cells.

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Fatostatin suppressed proliferation of androgen-responsive LNCaP and androgen-insensitive C4-2B prostate cancer cells with IC₅₀ values of 10.4 µmol/L and 9.1 µmol/L (72-hour treatment), respectively. The growth inhibition was dose- and time-dependent over 5 days of treatment.[3]
Fatostatin inhibited anchorage-independent colony formation in a soft agar assay in both LNCaP and C4-2B cells after a 3-week incubation in a dose-dependent manner.[3]
Fatostatin significantly decreased the invasive and migratory capabilities of LNCaP and C4-2B cells in Boyden chamber assays after 48-hour treatment.[3]
Fatostatin caused G₂/M cell cycle arrest in both LNCaP and C4-2B cells after 48-hour treatment, as determined by flow cytometry.[3]
Fatostatin induced apoptosis in LNCaP and C4-2B cells. Annexin V/PI staining showed increased early and late apoptotic populations. Caspase-3/7 enzymatic activity was significantly increased in a dose-dependent manner. Western blot analysis showed decreased full-length caspase-9, caspase-3, and PARP, and increased levels of their cleaved forms, indicating activation of the apoptotic cascade.[3]
Fatostatin decreased the expression of both precursor and nuclear forms of SREBP-1 and SREBP-2 in LNCaP and C4-2B cells in a dose-dependent manner (24-hour treatment). Immunofluorescence staining confirmed reduced nuclear localization of SREBPs.[3]
Fatostatin significantly down-regulated mRNA expression of SREBP target genes involved in lipogenesis (ACL, FASN, SCD-1) and cholesterogenesis (HMGCS1, HMGCR, MVK, MVD, LDLR), as well as chaperones (INSIG1, SCAP), as determined by qRT-PCR.[3]
Fatostatin decreased the protein levels of key enzymes FASN and HMGCR in a dose-dependent pattern.[3]
Luciferase reporter assays using promoters for HMGCoA Syn, FASN, and LDLR showed that Fatostatin significantly decreased their activities, but had no effect on mutant reporters lacking sterol regulatory elements (SRE). The inhibitory effect on SRE-dependent transcription was abolished when dominant-negative forms of SREBPs were expressed.[3]
Fatostatin reduced intracellular lipid accumulation (Oil Red O staining) and significantly decreased total free fatty acid levels in LNCaP and C4-2B cells after 48-hour treatment.[3]
Fatostatin reduced intracellular cholesterol accumulation (filipin staining) and significantly decreased total cholesterol levels in both cell lines after 48-hour treatment.[3]
Fatostatin decreased the protein expression of androgen receptor (AR) and its downstream target prostate-specific antigen (PSA) in LNCaP and C4-2B cells in a dose-dependent manner (24-hour treatment). It also blocked AR nuclear translocation.[3]
Kinetic analysis showed that Fatostatin first inhibited the nuclear translocation of SREBP-1 and SREBP-2 (at 6 hours), and subsequently decreased AR expression (at 12 hours) in both cell lines.[3]

Fatostatin (125B11) (30 mg/kg; 150 μL; i.p.; once daily for 28 days) decreases nutrition by reducing triglyceride (TG) stores, improves fatty liver disease, and reduces high ob/ob ratios in

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In a subcutaneous xenograft mouse model, athymic nu/nu male mice bearing C4-2B tumors (mean volume ~100 mm³) were treated with intraperitoneal injections of Fatostatin (15 mg/kg) or vehicle daily for 42 days. Fatostatin significantly inhibited tumor growth compared to the vehicle control group, as measured by tumor volume. The average excised tumor weight in the Fatostatin group was reduced to 18% of the control group.[3]
Serum PSA levels in Fatostatin-treated tumor-bearing mice were significantly lower than in control mice.[3]
Immunohistochemical (IHC) staining of tumors showed that Fatostatin treatment significantly decreased the proliferation index (Ki67-positive cells) and increased apoptosis (cleaved PARP-positive cells) compared to controls.[3]
qRT-PCR analysis of tumor tissues showed that Fatostatin significantly reduced mRNA levels of SREBP downstream target genes (ACL, FASN, SCD-1, HMGCS1, HMGCR, MVK, MVD, INSIG1, SCAP).[3]
Western blot and IHC staining of tumor tissues confirmed that Fatostatin decreased the protein expression of FASN, HMGCR, AR, and PSA compared to the vehicle group.[3]

Cell proliferation assay [1]
Cell Types: DU-145 Cell
Tested Concentrations: 0.1, 1 μM
Incubation Duration: 3 days
Experimental Results: Attenuated IGF1-induced growth at an IC50 of 0.1 μM.

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Cell Proliferation Assay (MTS): Prostate cancer cells were seeded in 96-well plates in triplicate and treated with vehicle or Fatostatin for 72 hours. Cell viability was determined using an MTS assay according to the manufacturer's instructions. IC₅₀ values were calculated.[3]
Growth Curve Assay: Cells were seeded in 24-well plates and treated with vehicle or Fatostatin (2.5, 5, or 10 µmol/L) for 5 days. Cell numbers from triplicate wells were counted daily using a hemocytometer.[3]
Soft Agar Colony Formation Assay: Cells were suspended in culture medium containing 0.3% agarose with vehicle or Fatostatin, and plated on top of a solidified 0.6% agarose layer in 6-well plates. Colonies were counted under a microscope after 3 weeks of incubation.[3]
Invasion and Migration Assay (Boyden Chamber): In vitro cell invasion or migration was determined in Boyden chambers pre-coated with Matrigel matrix (for invasion) or collagen I (for migration). After 48 hours of incubation, cells that invaded or migrated to the lower side of the membrane were photographed and counted.[3]
Quantitative Real-Time PCR (qRT-PCR): Total RNA was isolated from treated cells. cDNA was synthesized, and qPCR was performed using SYBR Green Master Mix and specific primer sets for target genes. Data were normalized to β-actin.[3]
Western Blot Analysis: Cell lysates were prepared from treated cells. Proteins were separated by SDS-PAGE, transferred to membranes, and probed with specific primary antibodies against target proteins (e.g., SREBPs, FASN, HMGCR, AR, PSA, caspases, PARP). Horseradish peroxidase-conjugated secondary antibodies and chemiluminescence detection were used.[3]
Filipin Staining (Cholesterol): Cells were fixed, quenched with glycine, and stained with filipin solution (50 µg/mL in PBS) for 1 hour. Images were captured using fluorescence microscopy.[3]
Oil Red O Staining (Lipids): Treated cells were stained with Oil Red O working solution and examined by phase contrast microscopy.[3]
Fatty Acid and Cholesterol Quantification: The amounts of free fatty acid and total cholesterol in treated cells were measured using commercial quantification kits according to the manufacturer's instructions.[3]
Cell Cycle Analysis by Flow Cytometry: Cells treated for 48 hours were fixed, stained with propidium iodide (PI, 25 µg/mL), and analyzed by flow cytometry based on DNA content to determine cell cycle distribution.[3]
Apoptosis Analysis: Apoptosis was assessed using an Annexin V-FITC/PI Apoptosis Detection Kit. Cells were stained and analyzed by flow cytometry. Caspase-3/7 activity was measured using a luminescent Caspase-Glo® 3/7 Assay.[3]
Luciferase Reporter Assay: NIH-3T3 cells were transfected with various promoter-luciferase constructs (e.g., pHMGCoASyn-Luc, pFASN-700-Luc, pLDLR-Luc) or their mutant versions (e.g., pFASN-700-mutSRE-Luc). After transfection, cells were treated with vehicle or Fatostatin for 20 hours. Luciferase activity was measured and normalized to co-transfected β-galactosidase activity.[3]

Animal/Disease Models: Four to five week old homozygous male obese (ob/ob) mice (C57BL/6J)[2]
Doses: 30 mg/kg; Hypertension[2]. 150 μL
Route of Administration: intraperitoneal (ip) injection; one time/day for 28 days
Experimental Results: Body weight, blood glucose, and hepatic fat accumulation in obese ob/ob mice were prevented even without controlling food intake.

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Subcutaneous Xenograft Model: Athymic nu/nu male mice (4-week-old) were subcutaneously implanted with C4-2B prostate cancer cells (1 × 10^6 cells). When the mean tumor volume reached approximately 100 mm³, mice were randomly divided into two groups. One group received daily intraperitoneal (i.p.) injections of Fatostatin (15 mg/kg), and the control group received sterile PBS (vehicle). Treatment continued for 42 days. Tumor volumes were measured regularly using calipers and calculated with the formula: Volume = 1/2 × length × width². Body weight was monitored. At the endpoint, blood was collected for serum PSA analysis, and tumors were harvested for weight measurement and further molecular analysis (IHC, qRT-PCR, Western blot).[3]

In in vivo xenotransplantation studies, mice treated daily with fatosstatin (15 mg/kg, intraperitoneal injection, for 42 days) did not have a significant difference in body weight compared to control mice treated with the vector, indicating that no significant systemic toxicity was observed under these experimental conditions. [3]

[1]. Identification of bioactive molecules by adipogenesis profiling of organic compounds. J Biol Chem. 2003 Feb 28;278(9):7320-4.

[2]. A small molecule that blocks fat synthesis by inhibiting the activation of SREBP. Chem Biol. 2009 Aug 28;16(8):882-92.

[3]. Fatostatin displays high antitumor activity in prostate cancer by blocking SREBP-regulated metabolic pathways and androgen receptor signaling. Mol Cancer Ther. 2014 Apr;13(4):855-66.

[4]. Fatostatin blocks ER exit of SCAP but inhibits cell growth in a SCAP-independent manner. J Lipid Res. 2016 Aug;57(8):1564-73.

[5]. Fatostatin, an SREBP inhibitor, prevented RANKL-induced bone loss by suppression of osteoclast differentiation. Biochim Biophys Acta. 2015 Nov;1852(11):2432-41.

4-(4-methylphenyl)-2-(2-propyl-4-pyridyl)thiazole belongs to the thiazole class of compounds.

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Lipstatin is a non-steroidal diarylthiazole derivative that was initially identified as an inhibitor of insulin-induced lipogenesis. It inhibits the nuclear translocation and activation of sterol regulatory element-binding protein (SREBP), a key transcription factor controlling genes related to fatty acid and cholesterol biosynthesis (lipogenesis and cholesterol synthesis). [3]
In prostate cancer, lipstatin exerts its antitumor effect by blocking SREBP-regulated metabolic pathways and simultaneously inhibiting the androgen receptor (AR) signaling pathway. It reduces the expression of lipogenic enzymes (e.g., FASN) and cholesterol-producing enzymes (e.g., HMGCR), thereby reducing intracellular fatty acid and cholesterol levels. It also inhibits the expression of androgen receptor (AR) and prostate-specific antigen (PSA). [3]
The proposed mechanism involves fatostatin inhibiting the processing/nuclear translocation of SREBP, thereby downregulating the expression of metabolic genes and AR, ultimately leading to the inhibition of prostate cancer cell proliferation, G₂/M phase arrest and apoptosis, as well as the suppression of tumor growth in vivo. [3]

C18H18N2S.HBR

375.32586

294.119

C, 73.43; H, 6.16; N, 9.52; S, 10.89

125256-00-0

Fatostatin hydrobromide;298197-04-3

1889993

White to yellow solid powder

5.133

0

3

4

21

314

0

CCCC1=NC=CC(C2=NC(C3=CC=C(C)C=C3)=CS2)=C1

ZROSUBKIGBSZCG-UHFFFAOYSA-N

InChI=1S/C18H18N2S/c1-3-4-16-11-15(9-10-19-16)18-20-17(12-21-18)14-7-5-13(2)6-8-14/h5-12H,3-4H2,1-2H3

2-(2-propylpyridin-4-yl)-4-(p-tolyl)thiazole

125B11; Fatostatin A; 125B-11

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 : ≥ 27 mg/mL (~91.71 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (8.49 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 25.0 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: 2.5 mg/mL (8.49 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 25.0 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: 2.5 mg/mL (8.49 mM) in 10% DMSO + 90% Corn Oil (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 25.0 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.)