Fatty Acid Synthase Inhibitor Research Articles

ACSS2 gene variants determine kidney disease risk by controlling de novo lipogenesis in kidney tubules.

Worldwide, over 800 million people are affected by kidney disease, yet its pathogenesis remains elusive, hindering the development of novel therapeutics. In this study, we used kidney-specific expression of quantitative traits and single-nucleus open chromatin analysis to show that genetic variants linked to kidney dysfunction on chromosome 20 target the acyl-CoA synthetase short-chain family 2 (ACSS2). By generating ACSS2-KO mice, we demonstrated their protection from kidney fibrosis in multiple disease models. Our analysis of primary tubular cells revealed that ACSS2 regulated de novo lipogenesis (DNL), causing NADPH depletion and increasing ROS levels, ultimately leading to NLRP3-dependent pyroptosis. Additionally, we discovered that pharmacological inhibition or genetic ablation of fatty acid synthase safeguarded kidney cells against profibrotic gene expression and prevented kidney disease in mice. Lipid accumulation and the expression of genes related to DNL were elevated in the kidneys of patients with fibrosis. Our findings pinpoint ACSS2 as a critical kidney disease gene and reveal the role of DNL in kidney disease.

Glyceryl triacetate promotes blood–brain barrier recovery after ischemic stroke through lipogenesis-mediated IL-33 in mice

BackgroundLipid metabolism has a crucial role in neural repair in neurodegenerative diseases. We recently revealed that lipogenesis-mediated interleukin-33 (IL-33) upregulation lead to blood–brain barrier (BBB) repair after ischemic stroke. However, manipulating the key enzyme fatty acid synthase (FASN) to enhance lipogenesis was very challenging. Glyceryl triacetate (GTA) was used as a donor of acetate and precursor of acetyl coenzyme A, the key substrate for de novo lipogenesis catalyzed by FASN. Therefore, we hypothesized that GTA would promote lipogenesis the peri-infarct after ischemic stroke and contribute to the BBB repair through IL-33.MethodsMiddle cerebral artery occlusion (MCAO) was performed on C57BL mice and GTA was gavage administrated (4 g/kg) on day 2 and 4 after MCAO. Lipogenesis was evaluated by assessment of the protein level of FASN, lipid droplets, and fatty acid products through liquid chromatography-mass spectrometry in the peri-infarct area on day 3 after MCAO, respectively. BBB permeability was determined by extravasation of Evans blue, IgG and dextran, and levels of tight junction proteins in the peri-infarct area on day 7 after MCAO, respectively. Infarct size and neurological defects were assessed on day 7 after MCAO. Brain atrophy on day 30 and long-term sensorimotor abilities after MCAO were analyzed as well. The inhibitor of FASN, C75 and the virus-delivered FASN shRNA were used to evaluate the role of FASN-driven lipogenesis in GTA-improved BBB repair. Finally, the therapeutic potential of recombinant IL-33 on BBB repair and neurological recovery was evaluated.ResultsWe found that treatment with GTA increased the lipogenesis as evidenced by lipid droplets level and lauric acid content, but not the FASN protein level. Treatment with GTA increased the IL-33 level in the peri-infarct area and decreased the BBB permeability after MCAO. However, infarct size and neurological defect score were unchanged on day 7 after MCAO, while the long-term recovery of sensorimotor function and brain atrophy were improved by GTA. Inhibition of lipogenesis using C75 or FASN shRNA reversed the beneficial effect of GTA. Finally, exogenous IL-33 improved BBB repair and long-term functional recovery after stroke.ConclusionCollectively, we concluded that treatment with GTA improved the BBB repair and functional recovery after ischemic stroke, probably by the enhancement of lipogenesis and IL-33 expression.Graphical

FASN Inhibitors Enhance Bestatin-Related Tumor Cell Apoptosis Through Upregulating PEPT1.

Fatty acid synthase (FASN) is generally over-expressed in human tumor tissues and catalyzes de novo synthesis of fatty acids on which tumor cells depend. Bestatin, an inhibitor of aminopeptidase/CD13, is one of the dipeptide substrates for the human oligopeptide transporter 1 (PEPT1). In the current study, we aimed to uncover the role of FASN inhibitors in bestatininduced tumor cell apoptosis and the underlying mechanism, extending our understanding of the correlations between FASN and PEPT1 in cancer and providing a new strategy for tumor targeted treatment. Cerulenin, orlistat and siRNAs were applied to inhibit FASN. The cell viability and apoptosis were assessed with MTT (thiazolyl blue tetrazolium bromide) assays and annexin VFITC/ PI staining with flow cytometry analysis. Western blot and qRT-PCR analysis were used to detect the protein levels and mRNA levels of the indicated genes in tumor cells, respectively. Protein degradation or stability was examined with cycloheximide chase assays. CD13 activity was detected by gelatin zymography. The HT1080 and C26 xenografts models were conducted to assess the efficacy in vivo. In the current study, we found that inhibiting FASN by cerulenin and orlistat both augmented the effects of bestatin in decreasing tumor cell viability. Cerulenin increased the apoptosis rates and enhanced the cleavage of PARP caused by bestatin. Furthermore, cerulenin, orlistat and siFASNs markedly elevated PEPT1 protein levels. Indeed, cerulenin induced the upregulation of PEPT1 mRNA expression rather than affecting the protein level after the cells were treated with CHX. And Gly-Sar, a typical competitive substrate of PEPT1, could attenuate the augment of bestatin-induced cell killing by cerulenin. Moreover, synergistic restrain of tumor growth accompanied by a reduction of Ki-67 and increment of TUNEL was significantly achieved in the xenograft models. Interestingly, no clear correlation was observed between the CD13 with FASN and/or PEPT1 in tumor cells. FASN inhibitors facilitate tumor cells susceptible to bestatin-induced apoptosis involving the up-regulation of PEPT1 at the mRNA translation level and the transport of bestatin by PEPT1, emerging as a promising strategy for tumor targeted therapy.

Study on the mechanism of action of effective monomeric, berberine of Xianglian Pill in inhibiting human colon cancer cells based on fatty acid synthase target.

Xianglian Wan (XLW) as a classic prescription of traditional Chinese medicine protects digestive function; however, few studies have investigated its anti-colorectal cancer effects. This study verified that the effective monomer berberine of XLW plays an antitumo r role by regulating the acetyl-CoA carboxylase (ACC)/fatty acid synthase (FASN) lipid metabolism-related signaling pathway. The connection between XLW and FASN was identified through literature mining, bioinformatics and structural biology. Invivo experiments verified the rationality of the antitumor effect of berberine by regulating the ACC/FASN pathway, and invitro experiments verified the regulatory relationship between berberine and FASN. The most frequent Chinese medicine component in XLW was Coptis chinensis. Berberine, the active ingredient of XLW, has a FASN binding site. FASN expression is higher in tumor tissues than in normal tissues. FASN is related to colorectal adenocarcinoma occurrence and patient survival time. Experiments showed that XLW, berberine and orlistat (FASN inhibitor) can cooperate with palmitic acid (PA) to inhibit tumors in mice. Berberine can downregulate FASN and ACC expression in tumor tissues and inhibit the increase in acetyl-CoA, the intermediate product of exogenous PA intake. The mechanism by which berberine inhibits colon cancer cell proliferation by lowering lipids is related to its downregulation of FASN protein expression. The ACC/FASN signaling pathway is a critical pathway through which berberine, the effective monomer of XLW, plays an antitumor role in colon cancer.

Serum Metabolomic Profile in Hypoxia-Induced Pulmonary Hypertension Mice after C75 Treatment.

Inhibition of fatty acid synthase (FAS) plays a crucial protective role in pulmonary hypertension (PH). Our aim was to identify novel metabolites in mice with hypoxia-induced PH after treatment with C75 (FAS inhibitor) and to confirm the presence of these metabolites in paediatric patients with PH. The PH mouse model was built by chronic hypoxia and ovalbumin (OVA) assistance. Untargeted metabolomics was used to analyse mouse serum. Six children with PH and six relative controls (patients without lung and heart disease) were selected in Shanghai Children's Hospital and they all performed blood tandem mass spectrometry during hospitalization. First, a total of 29 differential metabolites, including lipid metabolites, polyamine, and glutamine were identified as differential metabolites in the hypoxia group compared with the control group. After C75 treatment, symptoms were partially relieved in the PH mouse, and 15 differential metabolites, including lipid metabolites, polyamine, and glutamine were identified in the hypoxia + C75 group compared with the hypoxia group. These differential metabolites were enriched in arginine and glycerolipid metabolism through metabolite set enrichment analyses and were involved in excessive cell proliferation, which was a characteristic of PH. Second, glutamine and caproyl carnitine levels were increased in paediatric patients with PH. FAS may be a potential PH therapeutic target. Lipid metabolites, polyamine, and glutamine, are closely related to PH. Putrescine and glutamine might be biomarkers for PH.

Computational study on natural molecules targeting β-ketoacyl reductase domain of fatty acid synthase for the identification of selective inhibitors

Fatty acid synthase (FASN) enzyme is a lipid metabolism protein that provides the essential nutrients to cancer cells through de novo lipogenesis. Also, it plays a key role in other disease conditions, including obesity and inflammation. Hence, targeting the β-ketoacyl reductase (KR) domain of FASN protein, an in-silico study was performed on some selective bioactive natural molecules following a repurposing strategy to identify FASN inhibitors. A molecular docking study followed by Absorption, Distribution, Metabolism and Excretion (ADME) predictions, binding free energy calculations, and molecular dynamics (MD) simulations were performed against FASN protein (PDB ID:6NNA) using Schrodinger Drug Discovery Software. Compounds rutin, trans-chlorogenic acid, norbergenin, myricetin, quercetin, physalolactone, quercetin-3-O-galactoside, kaempferol, asperulosidic acid, luteolin, curcumin, 12-deoxywithastramonolide, pedunculoside, hernandifoline, and withafastuosin E were identified as hits, presenting better docking scores (–16.2, −14.1, −12.3, −12.1, −12.0, −11.3, −10.3, −9.8, −9.3, −9.2, −9.1, −8.5, −8.4, −8.3, –7.9, respectively) and hydrogen bond interactions with Ser 2021 and Tyr 2034 amino acids of the KR domain of FASN. The MD simulations study of top five hits in complex with protein 6NNA uncovered the significant interactions leading to the stabilization of ligand with Root Mean Square Deviation (RMSD) below 5.00 Å and the stability was further validated by evaluating the root mean square fluctuation, solvent accessible surface area, and radius of gyration graphs. Also, the FASN inhibition effect of top four hits (50 µM) was >50% when corroborated using High Performance Liquid Chromatography HPLC-based estimation of palmitic acid in MCF-7 cells. Thus rutin, trans-chlorogenic acid, norbergenin, and myricetin are proposed as prospective FASN inhibitory leads. Overall, the results provided useful modifications in pharmacophoric features that could improve the inhibitory effect. Communicated by Ramaswamy H. Sarma

Rapid Separation of Asiatic Acid, Quercetin, and Kaempferol from Traditional Chinese Medicine Centella asiatica (L.) Urban Using HSCCC-Semi-Prep-HPLC and the Assessment of Their Potential as Fatty Acid Synthase Inhibitors.

The main objective of this study was to rapidly separate asiatic acid (AA), quercetin (QCN), and kaempferol (KPL) from Centella asiatica (L.) Urban using high-speed counter-current chromatography (HSCCC) in tandem with the UV detector of semipreparative high-performance liquid chromatography (Semi-Prep-HPLC) and to evaluate their potential as inhibitors of fatty acid synthetase (FAS). To efficiently prepare large amounts of AA, QCN, and KPL from Centella asiatica (L.) Urban, rapid and simple methods by HSCCC were established respectively based on the partition coefficients (K values) of crude samples. The conditions of HSCCC-Semi-Prep-HPLC for the large-scale separation of AA, QCN, and KPL from Centella asiatica (L.) Urban were established and optimized. This included selecting the solvent system, flow rate, rotation speed, and so on. HSCCC-Semi-Prep-HPLC was successfully applied to separate and purify AA, QCN, and KPL, with n-hexane-n-butanol-methanol-water (3 : 1 : 3 : 3, V : V : V : V) as the solvent system for AA, which was detected at a wavelength of 210 nm with the stationary phase retention of 70%, and with n-hexane-ethyl acetate-methanol-water (0.8 : 0.9 : 1.2 : 1, V : V : V : V) as the solvent system for the co-separation of QCN and KPL, which was detected at a wavelength of 254 nm with the stationary phase retention of 65%. AA could be isolated at a large scale with high purity (>91.0%) in only one-step HSCCC-Semi-Prep-HPLC separation (within 150 min) under the optimized conditions. Meanwhile, QCN and KPL could be simultaneously isolated at a large scale with high purity (>99.1%) by another one-step HSCCC-Semi-Prep-HPLC separation (within 240 min) under the optimized conditions. The assessment of inhibition potential revealed that AA exhibited the strongest inhibitory effect on FAS, with an IC50 of 9.52 ± 0.76 μg/mL. Madecassic acid (MA) followed closely with IC50 values of 10.84 ± 0.92 μg/mL. QCN and KPL showed similar and relatively weaker inhibitory effects on FAS, with IC50 values of 43.09 ± 2.98 μg/mL and 36.90 ± 1.83 μg/mL, respectively. Overall, the HSCCC-Semi-Prep-HPLC method proved to be a highly efficient and reliable technique for separating AA, QCN, and KPL from Centella asiatica (L.) Urban, and the isolated compounds showed potential as FAS inhibitors.

Identification of phytochemicals as putative ligands for the targeted modulation of peroxisome proliferator‐activated receptor α (PPARα) in animals

The PPAR family of transcription factors are ligand-activated and regulate diverse functions including metabolic, neurological, and inflammatory diseases, neurodegenerative disorders, fertility or reproduction in the body. Specifically, PPARα is known to play a role in reducing the levels of circulating triglycerides and regulating energy homeostasis in livestock animals. This study aimed to identify phytochemicals that could serve as ligands for modulation of the bovine nuclear peroxisome proliferator-activated receptor alpha (PPARα) using molecular docking studies. Therefore, we investigated 1000 flavonoids belonging to different groups for their ability to bind to PPARα using molecular docking. Out of 1000, 6 top lead compounds with maximum binding affinity, evaluated through molecular docking, were further analysed for physicochemical properties and drug-likeness attributes. The results revealed that two flavonoids, Quercetin-3-o-rhamnoside and (-)- epicatechingallate, which are known fatty acid synthase inhibitors, demonstrated high docking scores with PPARα (−8.66 kcal/mol and −8.49 kcal/mol, respectively) and low RMSD values with PPARα (1.61 kcal/mol and 1.28 kcal/mol, respectively) as compared to PPARα agonist (synthetic), fenofibrate (−6.24 kcal/mol and 2.19 kcal/mol) and thus analyzed further for prediction of stability of docked complexes through MD simulations. MD simulation studies predicted the stability of complexes and the complex of Quercetin-3-o-rhamnoside and (-)- epicatechingallate were found to be stable at 100 ns based on RSMD value and RMSF residue index. Through computational analysis, the screened compounds showed good pharmacokinetic parameters, including non-toxicity, non-carcinogenic, high gastrointestinal absorption and thus can serve as potential drug candidates. Finally, the findings suggest that these phytochemicals have the potential to act as potent PPARα pharmacological agonists to prevent disease mechanisms and their related complications, providing insights into the role of phytochemicals as feed additives in animals for modulating PPARα functions. Communicated by Ramaswamy H. Sarma

Sortilin-Driven Cancer Secretome Enhances Tumorigenic Properties of Hepatocellular Carcinoma via de Novo Lipogenesis

A growing body of evidence suggests de novo lipogenesis as a key metabolic pathway adopted by cancers to fuel tumorigenic processes. While increased de novo lipogenesis has also been reported in hepatocellular carcinoma (HCC), understanding on molecular mechanisms driving de novo lipogenesis remains limited. In the present study, the functional role of sortilin, a member of the vacuolar protein sorting 10 protein receptor family, in HCC was investigated. Sortilin was overexpressed in HCC and was associated with poorer survival outcome. In functional studies, sortilin-overexpressing cells conferred tumorigenic phenotypes, namely, self-renewal and metastatic potential, of HCC cells via the cancer secretome. Proteomic profiling highlighted fatty acid metabolism as a potential molecular pathway associated with sortilin-driven cancer secretome. This finding was validated by the increased lipid content and expression of fatty acid synthase (FASN) in HCC cells treated with conditioned medium collected from sortilin-overexpressing cells. The enhanced tumorigenic properties endowed by sortilin-driven cancer secretome were partly abrogated by co-administration of FASN inhibitor C75. Further mechanistic dissection suggested protein stabilization by post-translational modification with O-GlcNAcylation as a major mechanism leading to augmented FASN expression. In conclusion, the present study uncovered the role of sortilin in hepatocarcinogenesis via modulation of the cancer secretome and deregulated lipid metabolism.

Hepatic FASN deficiency differentially affects nonalcoholic fatty liver disease and diabetes in mouse obesity models.

Nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes are interacting comorbidities of obesity, and increased hepatic de novo lipogenesis (DNL), driven by hyperinsulinemia and carbohydrate overload, contributes to their pathogenesis. Fatty acid synthase (FASN), a key enzyme of hepatic DNL, is upregulated in association with insulin resistance. However, the therapeutic potential of targeting FASN in hepatocytes for obesity-associated metabolic diseases is unknown. Here, we show that hepatic FASN deficiency differentially affects NAFLD and diabetes depending on the etiology of obesity. Hepatocyte-specific ablation of FASN ameliorated NAFLD and diabetes in melanocortin 4 receptor-deficient mice but not in mice with diet-induced obesity. In leptin-deficient mice, FASN ablation alleviated hepatic steatosis and improved glucose tolerance but exacerbated fed hyperglycemia and liver dysfunction. The beneficial effects of hepatic FASN deficiency on NAFLD and glucose metabolism were associated with suppression of DNL and attenuation of gluconeogenesis and fatty acid oxidation, respectively. The exacerbation of fed hyperglycemia by FASN ablation in leptin-deficient mice appeared attributable to impairment of hepatic glucose uptake triggered by glycogen accumulation and citrate-mediated inhibition of glycolysis. Further investigation of the therapeutic potential of hepatic FASN inhibition for NAFLD and diabetes in humans should thus consider the etiology of obesity.

Un-FASN-ing cancer’s seat belt: Linking lipid metabolism and antigen presentation

MHC-II expression on cancer cells is associated with improved treatment outcome. In this issue, Huang etal.1 report a panel of small molecules that selectively upregulate MHC-II on cancer cells through suppression of fatty acid synthase (FASN), resulting in inhibition of tumor growth. Targeting this link between lipid metabolism and antigen presentation may improve response to immunotherapy.

A broad inhibitor of acyl-acyl carrier protein synthetases

The acyl-acyl carrier protein synthetase enzyme enables some bacteria to scavenge free fatty acids from the environment for direct use in lipids. This fatty acid recycling pathway can help pathogens circumvent fatty acid synthase (FAS) inhibition with established antibiotics and those in clinical development. AasS enzymes are surprisingly hard to identify as they show high sequence similarity to other adenylate forming enzymes, and only a handful have been correctly annotated to date. Four recently discovered AasS enzymes from Gram negative bacteria, Chlamydia trachomatis, Neisseria gonorrhoeae, and Alistipes finegoldii, form distinct clusters in protein sequence similarity networks and have varying substrate preferences. We previously synthesized C10-AMS, an inhibitor of AasS that mimics the acyl-AMP reaction intermediate. Here we tested its ability to be broadly applicable to enzymes in this class, and found it inhibits all four newly annotated AasS enzymes. C10-AMS therefore provides a tool to study the role of AasS in fatty acid recycling in pathogenic bacteria as well as offers a platform for antibiotic development.

Hydrothermal Synthesis of Fe-Doped Cadmium Oxide Showed Bactericidal Behavior and Highly Efficient Visible Light Photocatalysis.

Cationic dyes present in industrial effluents significantly reduce the effectiveness of remediation operations. Considering the terrible impact of these pollutants on environment and biodiversity, investigating strategies to remove potentially harmful compounds from water is becoming an increasingly intriguing issue. In this work, we employed a simple hydrothermal technique to synthesize Fe-doped CdO (2, 4, and 6 wt %) nanostructures and assessed their efficacy in degrading methylene blue (MB) dye and inhibiting the growth of Staphylococcus aureus and Escherichia coli, respectively. Structural, morphological, and optical characterization of produced nanomaterials was also performed using X-ray diffraction, TEM, and UV absorption spectra. The photocatalytic decomposition of MB was significantly enhanced (58.8%) by using Fe (6 wt %)-doped CdO catalysts for 80 min under irradiation. In addition, 2.05-5.05 mm inhibitory zones were seen against Gram-positive bacteria (S. aureus), whereas the range for Gram-negative bacteria (E. coli) was 1.65-2.75 mm. These nanostructures were shown to be very effective inhibitors of beta-lactamase, d-alanine-d-alanine ligase B, and fatty acid synthase inhibitor by in silico molecular docking investigations.

Orlistat exerts anti-obesity and anti-tumorigenic effects in a transgenic mouse model of endometrial cancer.

Among all cancers, endometrial cancer is most strongly associated with obesity, with more than 65% of endometrial cancers attributable to obesity and being overweight. Fatty acid synthase (FAS), a key lipogenic enzyme, is expressed in endometrial cancer tumors and is associated with a worse prognosis for this disease. Orlistat, an FAS inhibitor, is an FDA-approved weight loss medication that has demonstrated anti-tumor activity in a variety of preclinical cancer models. In this study, the Lkb1fl/flp53fl/fl mouse model of endometroid endometrial cancer was exposed to three diet interventions, including a high fat diet (obese), a low fat diet (lean) and switch from a high fat to a low fat diet, and then exposed to orlistat or placebo. The mice fed a high-fat diet had significantly increased body weight and tumor weight compared to mice fed a low-fat diet. Switching from a high-fat diet to a low fat diet led to a reduction in mouse weight and suppressed tumor growth, as compared to both the high fat diet and low fat diet groups. Orlistat effectively decreased body weight in obese mice and inhibited tumor growth in obese, lean, and the high fat diet switch to low fat diet mouse groups through induction of apoptosis. Orlistat also showed anti-proliferative activity in nine of 11 primary cultures of human endometrial cancer. Our findings provide strong evidence that dietary intervention and orlistat have anti-tumor activity in vivo and supports further investigation of orlistat in combination with dietary interventions for the prevention and treatment of endometrial cancer.

PHYTOCHEMICAL COMPOUNDS FROM DYSPHANIA AMBROSOIDES LEAVES: A REVIEW OF BIOACTIVE CONSTITUENTS PRESENT IN THE PHYTOCOMPLEX

Objective: Dysphania ambrosioides (L.) Mosyakin & Clemants (Amaranthaceae), is a medicinal plant traditionally used for the treatment of pain, skin inflammations, fractures, and cardiac diseases. This study aimed to review the main phytochemical constituents from D. ambrosoides leaves, and the structure-activity relation of different compounds. Methodology: literature review, carried out between December 2022 and April 2023, through a bibliographic survey, in accordance with the recommended guidelines of PRISMA. The following descriptors were used “Dysphania ambrosioides”, “Chenopodium ambrosioides”, “leaves”, “traditional uses”, and “phytochemical constituents”, combining them with Boolean operators “AND” e “OR”, using electronic databases PubMed, and Google Scholar, published in the last 20 years and that addressed the theme. Results: D. ambrosioides is a promising ethnomedicinal plant and its leaves are a source of bioactive compounds such as α-terpinene, α-terpinenyl-acetate, beta-cymene, p-cymene, piperitone, carvyl acetate, piperitol acetate, trans-ascaridol, carvacrol, thymol, and limonene. In addition, chrysin, patulin, piperoylpiperidine, and scopoletin are present in this species. For these, the literature reports different mechanisms of action: PPAR –y agonist, Inhibitor of aromatase, Activation of the L-arginine/NO/cGMP/KATP pathway, an inhibitor of fatty acid synthase, Increase in glutathione peroxidase, and superoxide dismutase. Final considerations: more extensive number of preclinical pharmacological studies are performed to elucidate the molecular mechanisms of the components of the Phyto complex (bioactive constituents) isolated from D. ambrosioides leaves so that there is greater progress in the scientific validation for the use of the leaves as a source of therapeutic agents.

Radiation therapy promotes unsaturated fatty acids to maintain survival of glioblastoma

Radiation therapy (RT) is essential for the management of glioblastoma (GBM). However, GBM frequently relapses within the irradiated margins, thus suggesting that RT might stimulate mechanisms of resistance that limits its efficacy. GBM is recognized for its metabolic plasticity, but whether RT-induced resistance relies on metabolic adaptation remains unclear.Here, we show in vitro and in vivo that irradiated GBM tumors switch their metabolic program to accumulate lipids, especially unsaturated fatty acids. This resulted in an increased formation of lipid droplets to prevent endoplasmic reticulum (ER) stress. The reduction of lipid accumulation with genetic suppression and pharmacological inhibition of the fatty acid synthase (FASN), one of the main lipogenic enzymes, leads to mitochondrial dysfunction and increased apoptosis of irradiated GBM cells. Combination of FASN inhibition with focal RT improved the median survival of GBM-bearing mice. Supporting the translational value of these findings, retrospective analysis of the GLASS consortium dataset of matched GBM patients revealed an enrichment in lipid metabolism signature in recurrent GBM compared to primary.Overall, these results demonstrate that RT drives GBM resistance by generating a lipogenic environment permissive to GBM survival. Targeting lipid metabolism might be required to develop more effective anti-GBM strategies.

Co-Targeting FASN and mTOR Suppresses Uveal Melanoma Growth.

Uveal melanoma (UM) displays a high frequency of metastasis; however, effective therapies for metastatic UM are limited. Identifying unique metabolic features of UM may provide a potential targeting strategy. A lipid metabolism protein expression signature was induced in a normal choroidal melanocyte (NCM) line transduced with GNAQ (Q209L), a driver in UM growth and development. Consistently, UM cells expressed elevated levels of fatty acid synthase (FASN) compared to NCMs. FASN upregulation was associated with increased mammalian target of rapamycin (mTOR) activation and sterol regulatory element-binding protein 1 (SREBP1) levels. FASN and mTOR inhibitors alone significantly reduced UM cell growth. Concurrent inhibition of FASN and mTOR further reduced UM cell growth by promoting cell cycle arrest and inhibiting glucose utilization, TCA cycle metabolism, and de novo fatty acid biosynthesis. Our findings indicate that FASN is important for UM cell growth and co-inhibition of FASN and mTOR signaling may be considered for treatment of UM.

Design, synthesis, and anticancer activity of some novel 1H-benzo[d]imidazole-5-carboxamide derivatives as fatty acid synthase inhibitors

Multiple malignancies exhibit aberrant FASN expression, associated with enhanced de novo lipogenesis to meet the metabolic demands of rapidly proliferating tumour cells. Furthermore, elevated FASN expression has been linked to tumour aggressiveness and poor prognosis in a variety of malignant tumours, making FASN is an attractive target for anticancer drug discovery. Herein, we report the de novo design and synthesis of (2-(2-hydroxyphenyl)-1H-benzo[d]imidazol-5-yl)(piperazin-1-yl)methanone derivatives as novel FASN inhibitors with potential therapeutic applications in breast and colorectal cancers. Twelve (2-(2-hydroxyphenyl)-1H-benzo[d]imidazol-5-yl)(piperazin-1-yl)methanone derivatives (CTL) were synthesized and evaluated for FASN inhibition and cytotoxicity against colon cancer (HCT-116, Caco-2 cell lines), breast cancer (MCF-7 cell line) and normal cell line (HEK-293). Compounds CTL-06 and CTL-12 were chosen as the most promising lead molecules based on FASN inhibition and selective cytotoxicity profiles against colon and breast cancer cell lines. Compounds CTL-06 and CTL-12 demonstrate promising FASN inhibitory activity at IC50 of 3 ± 0.25 µM and 2.5 ± 0.25 µM when compared to the FASN inhibitor orlistat, which has an IC50 of 13.5 ± 1.0 µM. Mechanistic investigations on HCT-116 revealed that CTL-06 and CTL-12 treatment led to cell cycle arrest in Sub-G1/S phase along with apoptosis induction. Western blot studies indicated that CTL-06 and CTL-12 inhibited FASN expression in a dose-dependent manner. CTL-06 and CTL-12 treatment of HCT-116 cells enhanced caspase-9 expression in a dose-dependent manner, while upregulating proapoptotic marker Bax and downregulating antiapoptotic Bcl-xL. Molecular docking experiments of CTL-06 and CTL-12 with FASN enzyme revealed the mode of binding of these analogues in the KR domain of the enzyme.

Metabolic reprogramming of clear cell renal cell carcinoma.

Clear cell renal cell carcinoma (ccRCC) is a malignancy that exhibits metabolic reprogramming as a result of genetic mutations. This reprogramming accommodates the energy and anabolic needs of the cancer cells, leading to changes in glucose, lipid, and bio-oxidative metabolism, and in some cases, the amino acid metabolism. Recent evidence suggests that ccRCC may be classified as a metabolic disease. The metabolic alterations provide potential targets for novel therapeutic interventions or biomarkers for monitoring tumor growth and prognosis. This literature review summarized recent discoveries of metabolic alterations in ccRCC, including changes in glucose, lipid, and amino acid metabolism. The development of metabolic drugs targeting these metabolic pathways was also discussed, such as HIF-2α inhibitors, fatty acid synthase (FAS) inhibitors, glutaminase (GLS) inhibitors, indoleamine 2,3-dioxygenase (IDO) inhibitors, and arginine depletion. Future trends in drug development are proposed, including the use of combination therapies and personalized medicine approaches. In conclusion, this review provides a comprehensive overview of the metabolic alterations in ccRCC and highlights the potential for developing new treatments for this disease.

Inhibition of FASN as a potential treatment of advanced endocrine therapy-resistant breast cancer.

e13077 Background: The past decade has seen significant advancement in increasing survival estrogen receptor alpha (ERα) positive breast cancer. The use of selective estrogen receptor down-regulators and modulators (SERMs) and cyclin-dependent kinase inhibitors aided to extend overall survival of breast cancer patients. However, resistance to endocrine therapy is a common occurrence and patients will eventually succumb to their disease. Fatty acid synthase (FASN), a key enzyme in lipid biosynthesis, is overexpressed in more aggressive and therapy-resistant tumors, including breast cancers. FASN inhibitor, TVB-2640, has been evaluated in multiple tumor cell lines and in a phase 1 clinical study, and showed partial responses in 5 patients and multiple patients with prolonged stable disease (≥16 weeks). Methods: We generated therapy-resistant cells by long term exposure to tamoxifen (MCF7/TamR cells), and fulvestrant (MCF7/FR cells). Palbociclib-resistant (MCF7/RB1Crispr and ZR75/RB1Crispr) cells were generated through CRISPR/Cas9 knockout of the retinoblastoma (RB) gene. We assessed the impact of TVB-3166 inhibitor in these cells on proliferation, viability, cell cycle, apoptosis, ERα expression in patient derived explants, and tumor growth in xenografts. RNA sequencing of tamoxifen- and fulvestrant-resistant cells was performed to investigate gene expression. Subcellular localization of ERα was assessed using subcellular fractionations. Palmitoylation and ubiquitination of ERα were assessed by immunoprecipitation. ERα and p-eIF2α protein levels were analyzed by western blot after treatment with TVB with or without the addition of palmitate or BAPTA. Results: TVB treatment leads to a marked inhibition of proliferation in tamoxifen-, fulvestrant- and palbociclib-resistant cells compared to the parental cells. RNA sequencing of explants of patients with ERα positive disease showed down regulation of ESR1 related genes and genes involved in invasiveness. RNA sequencing of fulvestrant-resistant cells showed that treatment with TVB results in down regulation of EMT and E2F target genes, cholesterol homeostasis genes and mTORC1 signaling. Additionally, TVB significantly inhibited tumor growth in mice and decreased proliferation of primary tumor explants compared to untreated controls. FASN inhibition significantly reduced ERα levels most prominently in endocrine resistant cells and altered its subcellular localization. Furthermore, we showed that the reduction of ERα expression upon TVB treatment is mediated through the induction of endoplasmic reticulum stress. Conclusions: Our preclinical data provide evidence that FASN inhibition presents a promising therapeutic strategy for treatment of endocrine-resistant breast cancer. Further clinical development of FASN inhibitors for endocrine resistant breast cancer should be considered.