RESUMEN
To elucidate the possible biological roles of fatty acid-binding protein 5 (FABP5) in the intraocular environment, the cells from which FABP5 originates were determined by using four different intraocular tissue-derived cell types including human non-pigmented ciliary epithelium (HNPCE) cells, retinoblastoma (RB) cells, adult retinal pigment epithelial19 (ARPE19) cells and human ocular choroidal fibroblast (HOCF) cell lines, and the effects of FABP ligand 6, a specific inhibitor for FABP5 and FABP7 were analyzed by RNA sequencing and seahorse cellular metabolic measurements. Among these four different cell types, qPCR analysis showed that FABP5 was most prominently expressed in HNPCE cells, in which no mRNA expression of FABP7 was detected. In RNA sequencing analysis, 166 markedly up-regulated and 198 markedly down-regulated differentially expressed genes (DEGs) were detected between non-treated cells and cells treated with FABP ligand 6. IPA analysis of these DEGs suggested that FABP5 may be involved in essential roles required for cell development, cell survival and cell homeostasis. In support of this possibility, both mitochondrial and glycolytic functions of HNPCE cells, in which mRNA expression of FABP5, but not that of FABP7, was detected, were shown by using a Seahorse XFe96 Bioanalyzer to be dramatically suppressed by FABP ligand 6-induced inhibition of the activity of FABP5. Furthermore, in IPA upstream analysis, various unfolded protein response (UPR)-related factors were identified as upstream and causal network master regulators. Analysis by qPCR analysis showed significant upregulation of the mRNA expression of most of UPR-related factors and aquaporin1 (AQP1). The findings in this study suggest that HNPCE is one of intraocular cells producing FABP5 and may be involved in the maintenance of UPR and AQP1-related functions of HNPCE.
Asunto(s)
Proteínas de Unión a Ácidos Grasos , Humanos , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Línea Celular , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/citología , Células Epiteliales/metabolismo , Mitocondrias/metabolismo , Mitocondrias/genética , Regulación de la Expresión Génica , Cuerpo Ciliar/metabolismo , Cuerpo Ciliar/citología , GlucólisisRESUMEN
Chemotherapy is an important treatment option for advanced prostate cancer, especially for metastatic prostate cancer (PCa). Resistance to first-line chemotherapeutic drugs such as docetaxel often accompanies prostate cancer progression. Attempts to overcome resistance to docetaxel by combining docetaxel with other biological agents have been mostly unsuccessful. A better understanding of the mechanisms underlying docetaxel resistance may provide new avenues for the treatment of advanced PCa. We have previously found that the fatty acid-binding protein 12 (FABP12)-PPARγ pathway modulates lipid-related bioenergetics and PCa metastatic transformation through induction of Slug, a master driver of epithelial-to-mesenchymal transition (EMT). Here, we report that the FABP12-Slug axis also underlies chemoresistance in PCa cells. Cell sensitivity to docetaxel is markedly suppressed in FABP12-expressing cells, along with induction of Survivin, a typical apoptosis inhibitor, and inhibition of cleaved PARP, a hallmark of programmed cell death. Importantly, Slug depletion down-regulates Survivin and restores cell sensitivity to docetaxel in FABP12-expressing cells. Finally, we also show that high levels of Survivin are associated with poor prognosis in PCa patients, with FABP12 status determining its prognostic significance. Our research identifies a FABP12-Slug-Survivin pathway driving docetaxel resistance in PCa cells, suggesting that targeting FABP12 may be a precision approach to improve chemodrug efficacy and curb metastatic progression in PCa.
Asunto(s)
Docetaxel , Proteínas de Unión a Ácidos Grasos , Neoplasias de la Próstata , Factores de Transcripción de la Familia Snail , Survivin , Humanos , Masculino , Docetaxel/farmacología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Survivin/metabolismo , Survivin/genética , Factores de Transcripción de la Familia Snail/metabolismo , Factores de Transcripción de la Familia Snail/genética , Línea Celular Tumoral , Resistencia a Antineoplásicos/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Muerte Celular/efectos de los fármacosRESUMEN
Fatty acid-binding protein 1 (FABP1) plays an important role in regulating fatty acid metabolism in liver, which is a potential therapeutic target for diseases such as non-alcoholic fatty liver disease (NAFLD). However, the underlying mechanisms are not well defined. Using complementary experimental models, we discovered FABP1 induction in hepatocytes as a primary mediator of lipogenesis when exposed to fatty acids, especially saturated fatty acids (SFAs). In the feeding trial, palm oil led to excess lipid accumulation in the liver of large yellow croaker (Larimichthys crocea), accompanied by significant induction of FABP1. In cultured cells, palmitic acid (PA), a kind of SFA, triggered the fabp1 expression and increased triglyceride (TG) contents. Knockdown of FABP1 dampened PA-induced TG accumulation through mitigated lipogenesis. The overexpression of FABP1 showed the opposite result. Furthermore, the inactivation of FABP1 led to induction in insulin-induced gene 1 (INSIG1) expression, which attenuated the processing of sterol regulatory element-binding protein 1 (SREBP1) by down-regulating the nuclear-localized SREBP1. These results revealed a previously unrecognized function of FABP1 in response to PA, providing additional evidence for targeting FABP1 in the treatment of NAFLD caused by SFA.
Asunto(s)
Proteínas de Unión a Ácidos Grasos , Hepatocitos , Lipogénesis , Perciformes , Proteína 1 de Unión a los Elementos Reguladores de Esteroles , Animales , Hepatocitos/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Perciformes/metabolismo , Perciformes/genética , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Triglicéridos/metabolismo , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Ácido Palmítico/farmacología , Células CultivadasRESUMEN
Colorectal cancer (CRC) is among the most prevalent cancers with a high mortality rate. Both genetic and environmental factors contribute to CRC development. This study aimed to assess the association of single nucleotide polymorphisms (SNPs) in the fatty acid binding protein-2 (rs1799883), Cytochrome P450 2E1 (rs3813865), TP53 (rs1042522), and Murine double minute 2 (rs1042522) genes with CRC. A cross-sectional case-control study was conducted at the Institute of Molecular Biology and Biotechnology from May 2020 to March 2021, involving CRC patients (N = 100) and controls (N = 100) recruited from the Multan district in Pakistan. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and tetra-primer amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) were employed to investigate the studied SNPs. The association of SNPs in all genes with CRC was examined either individually or in various combinations. Genotypes at three SNPs, rs1799883 in FABP2, rs3813865 in CYP2E1, and rs1042522 in TP53, were found to be associated with the development of CRC, while rs1042522 in MDM2 was not. Patients who were married, smoked, lacked exercise habits or had a family history of CRC were at a greater risk of acquiring the disease. FABP2 gene rs1799883, CYP2E1 gene rs3813865, and TP53 gene rs1042522 polymorphisms are significant in the development of CRC in Pakistani participants.
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Neoplasias Colorrectales , Citocromo P-450 CYP2E1 , Proteínas de Unión a Ácidos Grasos , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Proteína p53 Supresora de Tumor , Humanos , Neoplasias Colorrectales/genética , Masculino , Femenino , Citocromo P-450 CYP2E1/genética , Proteínas de Unión a Ácidos Grasos/genética , Persona de Mediana Edad , Proteína p53 Supresora de Tumor/genética , Estudios de Casos y Controles , Estudios Transversales , Anciano , Adulto , Pakistán/epidemiología , GenotipoRESUMEN
Fatty acid-binding protein 4 (FABP4) plays an essential role in metabolism and inflammation. However, the role of FABP4 in alcoholic steatohepatitis (ASH) remains unclear. This study aimed to investigate the function and underlying mechanisms of FABP4 in the progression of ASH. We first obtained alcoholic hepatitis (AH) datasets from the National Center for Biotechnology Information-Gene Expression Omnibus database and conducted bioinformatics analysis to identify critical genes in the FABP family. We then established ASH models of the wild-type (WT) and Fabp4-deficient (Fabp4-/-) mice to investigate the role of FABP4 in ASH. Additionally, we performed transcriptional profiling of mouse liver tissue and analyzed the results using integrative bioinformatics. The FABP4-associated signaling pathway was further verified. FABP4 was upregulated in two AH datasets and was thus identified as a critical biomarker for AH. FABP4 expression was higher in the liver tissues of patients with alcoholic liver disease and ASH mice than in the corresponding control samples. Furthermore, the Fabp4-/- ASH mice showed reduced hepatic lipid deposition and inflammation compared with the WT ASH mice. Mechanistically, Fabp4 may be involved in regulating the p53 and sirtuin-1 signaling pathways, subsequently affecting lipid metabolism and macrophage polarization in the liver of ASH mice. Our results demonstrate that Fabp4 is involved in the progression of ASH and that Fabp4 deficiency may ameliorate ASH. Therefore, FABP4 may be a potential therapeutic target for ASH treatment.
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Proteínas de Unión a Ácidos Grasos , Hígado Graso Alcohólico , Transducción de Señal , Proteína p53 Supresora de Tumor , Animales , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Ratones , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Hígado Graso Alcohólico/metabolismo , Hígado Graso Alcohólico/genética , Hígado Graso Alcohólico/patología , Ratones Noqueados , Humanos , Masculino , Modelos Animales de Enfermedad , Hígado/metabolismo , Hígado/patología , Ratones Endogámicos C57BL , Sirtuina 1/metabolismo , Sirtuina 1/genética , Metabolismo de los LípidosRESUMEN
Fatty acid-binding proteins (FABPs) are small intracellular proteins that regulate fatty acid metabolism, transport, and signalling. There are ten known human isoforms, many of which are upregulated and involved in clinical pathologies. As such, FABP inhibition may be beneficial in disease states such as cancer, and those involving the cardiovascular system, metabolism, immunity, and cognition. Recently, a potent, selective FABP5 inhibitor (ART26.12), with 90-fold selectivity to FABP3 and 20-fold selectivity to FABP7, was found to be remarkably benign, with a no-observed-adverse-effect level of 1000 mg/kg in rats and dogs, showing no genotoxicity, cardiovascular, central, or respiratory toxicity. To understand the potential implication of FABP inhibition more fully, this review systematically assessed literature investigating genetic knockout, knockdown, and pharmacological inhibition of FABP3, FABP4, FABP5, or FABP7. Analysis of the literature revealed that animals bred not to express FABPs showed the most biological effects, suggesting key roles of these proteins during development. FABP ablation sometimes exacerbated symptoms of disease models, particularly those linked to metabolism, inflammatory and immune responses, cardiac contractility, neurogenesis, and cognition. However, FABP inhibition (genetic silencing or pharmacological) had a positive effect in many more disease conditions. Several polymorphisms of each FABP gene have also been linked to pathological conditions, but it was unclear how several polymorphisms affected protein function. Overall, analysis of the literature to date suggests that pharmacological inhibition of FABPs in adults is of low risk.
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Proteínas de Unión a Ácidos Grasos , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Animales , Humanos , PerrosRESUMEN
Hyperlipidemia and hypertension might play a role in cardiac fibrosis, in which a heterogeneous population of fibroblasts seems important. However, it is unknown whether CD34+ progenitor cells are involved in the pathogenesis of heart fibrosis. This study aimed to explore the mechanism of CD34+ cell differentiation in cardiac fibrosis during hyperlipidemia. Through the analysis of transcriptomes from 50,870 single cells extracted from mouse hearts and 76,851 single cells from human hearts, we have effectively demonstrated the evolving cellular landscape throughout cardiac fibrosis. Disturbances in lipid metabolism can accelerate the development of fibrosis. Through the integration of bone marrow transplantation models and lineage tracing, our study showed that hyperlipidemia can expedite the differentiation of non-bone marrow-derived CD34+ cells into fibroblasts, particularly FABP4+ fibroblasts, in response to angiotensin II. Interestingly, the partial depletion of CD34+ cells led to a notable reduction in triglycerides in the heart, mitigated fibrosis, and improved cardiac function. Furthermore, immunostaining of human heart tissue revealed colocalization of CD34+ cells and fibroblasts. Mechanistically, our investigation of single-cell RNA sequencing data through pseudotime analysis combined with in vitro cellular studies revealed the crucial role of the PPARγ/Akt/Gsk3ß pathway in orchestrating the differentiation of CD34+ cells into FABP4+ fibroblasts. Through our study, we generated valuable insights into the cellular landscape of CD34+ cell-derived cells in the hypertrophic heart with hyperlipidemia, indicating that the differentiation of non-bone marrow-derived CD34+ cells into FABP4+ fibroblasts during this process accelerates lipid accumulation and promotes heart failure via the PPARγ/Akt/Gsk3ß pathway.
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Antígenos CD34 , Diferenciación Celular , Proteínas de Unión a Ácidos Grasos , Fibroblastos , Fibrosis , Metabolismo de los Lípidos , Fibroblastos/metabolismo , Fibroblastos/patología , Humanos , Ratones , Animales , Antígenos CD34/metabolismo , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Miocardio/metabolismo , Miocardio/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Hiperlipidemias/metabolismo , Hiperlipidemias/patología , Masculino , Transducción de Señal , PPAR gamma/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Modelos Animales de EnfermedadRESUMEN
The regenerative ability of limb bones after injury decreases during aging, but whether a similar phenomenon occurs in jawbones and whether autophagy plays a role in this process remain unclear. Through retrospective analysis of clinical data and studies on a mouse model of jawbone defects, we confirmed the presence of delayed or impaired bone regeneration in the jawbones of old individuals and mice. Subsequently, osteoblasts (OBs) derived from mouse jawbones were isolated, showing reduced osteogenesis in senescent osteoblasts (S-OBs). We observed a reduction in autophagy within both aged jawbones and S-OBs. Additionally, pharmacological inhibition of autophagy in normal OBs (N-OBs) led to cell aging and decreased osteogenesis, while autophagic activation reversed the aging phenotype of S-OBs. The activator rapamycin (RAPA) increased the autophagy level and bone regeneration in aged jawbones. Finally, we found that fatty acid-binding protein 3 (FABP3) was degraded by autolysosomes through its interaction with sequestosome 1 (P62/SQSTM1). Autophagy inhibition within senescent jawbones and S-OBs led to the excessive accumulation of FABP3, and FABP3 knockdown partially rescued the decreased osteogenesis in S-OBs and alleviated age-related compromised jawbone regeneration. In summary, we confirmed that autophagy inhibition plays an important role in delaying bone regeneration in aging jawbones. Autophagic activation or FABP3 knockdown can partially rescue the osteogenesis of S-OBs and the regeneration of aging jawbones, providing insight into jawbone aging.
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Envejecimiento , Autofagia , Regeneración Ósea , Proteínas de Unión a Ácidos Grasos , Osteoblastos , Osteogénesis , Animales , Femenino , Humanos , Masculino , Ratones , Envejecimiento/fisiología , Envejecimiento/metabolismo , Autofagia/fisiología , Senescencia Celular/fisiología , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Maxilares , Ratones Endogámicos C57BL , Osteoblastos/metabolismo , Osteogénesis/fisiologíaRESUMEN
Fatty acid-binding proteins (FABPs), a family of lipid chaperone molecules that are involved in intracellular lipid transportation to specific cellular compartments, stimulate lipid-associated responses such as biological signaling, membrane synthesis, transcriptional regulation, and lipid synthesis. Previous studies have shown that FABP4, a member of this family of proteins that are expressed in adipocytes and macrophages, plays pivotal roles in the pathogenesis of various cardiovascular and metabolic diseases, including diabetes mellitus (DM) and hypertension (HT). Since significant increases in the serum levels of FABP4 were detected in those patients, FABP4 has been identified as a crucial biomarker for these systemic diseases. In addition, in the field of ophthalmology, our group found that intraocular levels of FABP4 (ioFABP4) and free fatty acids (ioFFA) were substantially elevated in patients with retinal vascular diseases (RVDs) including proliferative diabetic retinopathy (PDR) and retinal vein occlusion (RVO), for which DM and HT are also recognized as significant risk factors. Recent studies have also revealed that ioFABP4 plays important roles in both retinal physiology and pathogenesis, and the results of these studies have suggested potential molecular targets for retinal diseases that might lead to future new therapeutic strategies.
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Proteínas de Unión a Ácidos Grasos , Humanos , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Animales , Enfermedades de la Retina/metabolismo , Retina/metabolismo , Retinopatía Diabética/metabolismoRESUMEN
Hepatic adipogenesis has common mechanisms with adipocyte differentiation such as PPARγ involvement and the induction of adipose tissue-specific molecules. A previous report demonstrated that integrator complex subunit 6 (INTS6) is required for adipocyte differentiation. This study aimed to investigate INTS6 expression and its role in hepatic steatosis progression. The expression of INTS6 and PPARγ was examined in the liver of a mouse model of steatohepatitis and in paired liver biopsy samples from 11 patients with severe obesity and histologically proven metabolic dysfunction associated steatohepatitis (MASH) before and one year after bariatric surgery. To induce hepatocellular steatosis in vitro, an immortalized human hepatocyte cell line Hc3716 was treated with free fatty acids. In the steatohepatitis mouse model, we observed hepatic induction of INTS6, PPARγ, and adipocyte-specific genes. In contrast, ß-catenin which negatively regulates PPARγ was reduced. Biopsied human livers demonstrated a strong positive correlation (r2 = 0.8755) between INTS6 and PPARγ mRNA levels. After bariatric surgery, gene expressions of PPARγ, FABP4, and CD36 were mostly downregulated. In our in vitro experiments, we observed a concentration-dependent increase in Oil Red O staining in Hc3716 cells after treatment with the free fatty acids. Alongside this change, the expression of INTS6, PPARγ, and adipocyte-specific genes was induced. INTS6 knockdown using siRNA significantly suppressed cellular lipid accumulation together with induction of ß-catenin and PPARγ downregulation. Collectively, INTS6 expression closely correlates with PPARγ. INTS6 suppression significantly reduced hepatocyte steatosis via ß-catenin-PPARγ axis, indicating that INTS6 could be a novel therapeutic target for treating MASH.
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PPAR gamma , beta Catenina , PPAR gamma/metabolismo , PPAR gamma/genética , Humanos , Animales , beta Catenina/metabolismo , beta Catenina/genética , Ratones , Masculino , Hígado Graso/metabolismo , Hígado Graso/patología , Hígado Graso/genética , Femenino , Hepatocitos/metabolismo , Hepatocitos/patología , Línea Celular , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Hígado/metabolismo , Hígado/patología , Persona de Mediana Edad , Adulto , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Antígenos CD36/metabolismo , Antígenos CD36/genéticaRESUMEN
PURPOSE: Alzheimer's disease (AD) is associated with brain accumulation of amyloid-beta (Aß) and neurofibrillary tangle formation, in addition to reduced brain docosahexaenoic acid (DHA) and increased brain iron levels. DHA requires access across the blood-brain barrier (BBB) to enter the brain, and iron has been shown to affect the expression and function of a number of BBB transporters. Therefore, this study aimed to assess the effect of iron on the expression and function of fatty acid binding protein 5 (FABP5) and fatty acid transport protein 1 (FATP1), both which mediate brain endothelial cell trafficking of DHA. METHODS: The mRNA and protein levels of FABP5 and FATP1 in human cerebral microvascular endothelial (hCMEC/D3) cells was assessed by RT-qPCR and Western blot, respectively following ferric ammonium citrate (FAC) treatment (up to 750 µM, 72 h). The function of FABP5 and FATP1 was assessed via uptake and efflux of radiolabelled 3H-oleic acid and 14C-DHA. RESULTS: FAC (500 µM, 72 h) had no impact on the expression of FABP5 at the protein and mRNA level in hCMEC/D3 cells, which was associated with a lack of effect on the uptake of 14C-DHA. FAC led to a 19.7% reduction in FATP1 protein abundance in hCMEC/D3 cells with no impact on mRNA levels, and this was associated with up to a 32.6% reduction in efflux of 14C-DHA. CONCLUSIONS: These studies demonstrate a role of iron in down-regulating FATP1 protein abundance and function at the BBB, which may have implications on fatty acid access to the brain.
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Barrera Hematoencefálica , Encéfalo , Células Endoteliales , Proteínas de Transporte de Ácidos Grasos , Proteínas de Unión a Ácidos Grasos , Humanos , Proteínas de Transporte de Ácidos Grasos/metabolismo , Proteínas de Transporte de Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Células Endoteliales/metabolismo , Células Endoteliales/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/efectos de los fármacos , Ácidos Grasos/metabolismo , Compuestos Férricos , Línea Celular , Transporte Biológico/efectos de los fármacos , Compuestos de Amonio Cuaternario/farmacología , Hierro/metabolismo , Microvasos/metabolismo , Microvasos/citología , Microvasos/efectos de los fármacos , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , ARN Mensajero/metabolismo , ARN Mensajero/genética , Ácidos Docosahexaenoicos/farmacologíaRESUMEN
BACKGROUND: Breast cancer is the most common cancer in women diagnosed in the U.S. and worldwide. Obesity increases breast cancer risk without clear underlying molecular mechanisms. Our studies demonstrate that circulating adipose fatty acid binding protein (A-FABP, or FABP4) links obesity-induced dysregulated lipid metabolism and breast cancer risk, thus potentially offering a new target for breast cancer treatment. METHODS: We immunized FABP4 knockout mice with recombinant human FABP4 and screened hybridoma clones with specific binding to FABP4. The potential effects of antibodies on breast cancer cells in vitro were evaluated using migration, invasion, and limiting dilution assays. Tumor progression in vivo was evaluated in various types of tumorigenesis models including C57BL/6 mice, Balb/c mice, and SCID mice. The phenotype and function of immune cells in tumor microenvironment were characterized with multi-color flow cytometry. Tumor stemness was detected by ALDH assays. To characterize antigen-antibody binding capacity, we determined the dissociation constant of selected anti-FABP4 antibodies via surface plasmon resonance. Further analyses in tumor tissue were performed using 10X Genomics Visium spatial single cell technology. RESULTS: Herein, we report the generation of humanized monoclonal antibodies blocking FABP4 activity for breast cancer treatment in mouse models. One clone, named 12G2, which significantly reduced circulating levels of FABP4 and inhibited mammary tumor growth, was selected for further characterization. After confirming the therapeutic efficacy of the chimeric 12G2 monoclonal antibody consisting of mouse variable regions and human IgG1 constant regions, 16 humanized 12G2 monoclonal antibody variants were generated by grafting its complementary determining regions to selected human germline sequences. Humanized V9 monoclonal antibody showed consistent results in inhibiting mammary tumor growth and metastasis by affecting tumor cell mitochondrial metabolism. CONCLUSIONS: Our current evidence suggests that targeting FABP4 with humanized monoclonal antibodies may represent a novel strategy for the treatment of breast cancer and possibly other obesity- associated diseases.
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Neoplasias de la Mama , Proteínas de Unión a Ácidos Grasos , Animales , Proteínas de Unión a Ácidos Grasos/antagonistas & inhibidores , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/inmunología , Humanos , Femenino , Ratones , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/patología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Anticuerpos Monoclonales Humanizados/farmacología , Anticuerpos Monoclonales Humanizados/uso terapéutico , Ratones Noqueados , Ensayos Antitumor por Modelo de Xenoinjerto , Microambiente Tumoral/inmunología , Modelos Animales de Enfermedad , Ratones SCIDRESUMEN
Non-muscle invasive bladder cancers (NMIBC) pTa-pT1 are depicted by a high risk of recurrence and/or progression with an unpredictable clinical evolution. Our aim was to identify, from the original resection specimen, tumors that will progress to better manage patients. We previously showed that A-FABP (Adipocyte- Fatty Acid Binding Protein) loss predicted NMIBC progression. Here we determined by immunohistochemistry the prognostic value of E-FABP (Epidermal-Fatty Acid Binding Protein) expression in 210 tumors (80 pTa, 75 pT1, 55 pT2-T4). Thus, E-FABP low expression was correlated with a high grade/stage, the presence of metastatic lymph nodes, and visceral metastases (p < 0.001). Unlike A-FABP in NMIBC, E-FABP low expression was not associated with RFS or PFS in Kaplan-Meier analysis. But patients of the overall cohort with a high E-FABP expression had a longer mOS (53.8 months vs. 29.3 months, p = 0.029). The immunohistochemical analysis on the same NMIBC tissue sections revealed that when A-FABP is absent, a high E-FABP expression is detected. E-FABP could compensate A-FABP loss. Interestingly, patients, whose original tumor presents both low E-FABP and negative A-FABP, had the worse survival, those maintaining the expression of both markers had better survival. To conclude, the combined evaluation of A- and E-FABP expression allowed to stratify patients with urothelial carcinoma for optimizing treatment and follow-up.
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Proteínas de Unión a Ácidos Grasos , Neoplasias de la Vejiga Urinaria , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Biomarcadores de Tumor/metabolismo , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Inmunohistoquímica , Estimación de Kaplan-Meier , Pronóstico , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/mortalidad , Neoplasias de la Vejiga Urinaria/genéticaRESUMEN
In zebrafish, like in mammals, radial glial cells (RGCs) can act as neural progenitors during development and regeneration in adults. However, the heterogeneity of glia subpopulations entails the need for different specific markers of zebrafish glia. Currently, fluorescent protein expression mediated by a regulatory element from the glial fibrillary acidic protein (gfap) gene is used as a prominent glia reporter. We now expand this tool by demonstrating that a regulatory element from the mouse Fatty acid binding protein 7 (Fabp7) gene drives reliable expression in fabp7-expressing zebrafish glial cells. By using three different Fabp7 regulatory element-mediated fluorescent protein reporter strains, we reveal in double transgenic zebrafish that progenitor cells expressing fluorescent proteins driven by the Fabp7 regulatory element give rise to radial glia, oligodendrocyte progenitors, and some neuronal precursors. Furthermore, Bergmann glia represent the almost only glial population of the zebrafish cerebellum (besides a few oligodendrocytes), and the radial glia also remain in the mature cerebellum. Fabp7 regulatory element-mediated reporter protein expression in Bergmann glia progenitors suggests their origin from the ventral cerebellar proliferation zone, the ventricular zone, but not from the dorsally positioned upper rhombic lip. These new Fabp7 reporters will be valuable for functional studies during development and regeneration.
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Animales Modificados Genéticamente , Proteína de Unión a los Ácidos Grasos 7 , Pez Cebra , Animales , Pez Cebra/genética , Pez Cebra/metabolismo , Proteína de Unión a los Ácidos Grasos 7/metabolismo , Proteína de Unión a los Ácidos Grasos 7/genética , Neuroglía/metabolismo , Cerebelo/metabolismo , Cerebelo/citología , Oligodendroglía/metabolismo , Oligodendroglía/citología , Ratones , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Pez Cebra/metabolismo , Proteínas de Pez Cebra/genéticaRESUMEN
Melanoma clinical outcomes emerge from incompletely understood genetic mechanisms operating within the tumor and its microenvironment. Here, we used single-cell RNA-based spatial molecular imaging (RNA-SMI) in patient-derived archival tumors to reveal clinically relevant markers of malignancy progression and prognosis. We examined spatial gene expression of 203,472 cells inside benign and malignant melanocytic neoplasms, including melanocytic nevi and primary invasive and metastatic melanomas. Algorithmic cell clustering paired with intratumoral comparative two-dimensional analyses visualized synergistic, spatial gene signatures linking cellular proliferation, metabolism, and malignancy, validated by protein expression. Metastatic niches included up-regulation of CDK2 and FABP5, which independently predicted poor clinical outcome in 473 patients with melanoma via Cox regression analysis. More generally, our work demonstrates a framework for applying single-cell RNA-SMI technology toward identifying gene regulatory landscapes pertinent to cancer progression and patient survival.
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Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Melanoma , Análisis de la Célula Individual , Humanos , Melanoma/patología , Melanoma/genética , Melanoma/metabolismo , Melanoma/mortalidad , Pronóstico , Análisis de la Célula Individual/métodos , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/genética , Quinasa 2 Dependiente de la Ciclina/metabolismo , Quinasa 2 Dependiente de la Ciclina/genética , Microambiente Tumoral , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Femenino , Masculino , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/mortalidad , Perfilación de la Expresión GénicaRESUMEN
The protein tyrosine phosphatase Src homology region 2 domain-containing phosphatase-1 (SHP-1) plays an important role in modulating glucose and lipid homeostasis. We previously suggested a potential role of SHP-1 in the regulation of peroxisome proliferator-activated receptor γ2 (PPARγ2) expression and activity but the mechanisms were unexplored. PPARγ2 is the master regulator of adipogenesis, but how its activity is regulated by tyrosine phosphorylation is largely unknown. Here, we found that SHP-1 binds to PPARγ2 primarily via its N-terminal SH2-domain. We confirmed the phosphorylation of PPARγ2 on tyrosine-residue 78 (Y78), which was reduced by SHP-1 in vitro resulting in decreased PPARγ2 stability. Loss of SHP-1 led to elevated, agonist-induced expression of the classical PPARγ2 targets FABP4 and CD36, concomitant with increased lipid content in cells expressing PPARγ2, an effect blunted by abrogation of PPARγ2 phosphorylation. Collectively, we discovered that SHP-1 affects the stability of PPARγ2 through dephosphorylation thereby influencing adipogenesis.
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Adipogénesis , PPAR gamma , Proteína Tirosina Fosfatasa no Receptora Tipo 6 , PPAR gamma/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Fosforilación , Humanos , Animales , Ratones , Antígenos CD36/metabolismo , Antígenos CD36/genética , Células HEK293 , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Estabilidad Proteica , Células 3T3-L1 , Dominios Homologos src , Unión ProteicaRESUMEN
Type 1 diabetes (T1D) is a chronic disease characterized by self-destruction of insulin-producing pancreatic ß cells by cytotoxic T cell activity. However, the pathogenic mechanism of T cell infiltration remains obscure. Recently, tissue-resident memory T (TRM) cells have been shown to contribute to cytotoxic T cell recruitment. TRM cells are found present in human pancreas and are suggested to modulate immune homeostasis. Here, the role of TRM cells in the development of T1D is investigated. The presence of TRM cells in pancreatic islets is observed in non-obese diabetic (NOD) mice before T1D onset. Mechanistically, elevated fatty acid-binding protein 4 (FABP4) potentiates the survival and alarming function of TRM cells by promoting fatty acid utilization and C-X-C motif chemokine 10 (CXCL10) secretion, respectively. In NOD mice, genetic deletion of FABP4 or depletion of TRM cells using CD69 neutralizing antibodies resulted in a similar reduction of pancreatic cytotoxic T cell recruitment, a delay in diabetic incidence, and a suppression of CXCL10 production. Thus, targeting FABP4 may represent a promising therapeutic strategy for T1D.
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Quimiocina CXCL10 , Diabetes Mellitus Tipo 1 , Proteínas de Unión a Ácidos Grasos , Islotes Pancreáticos , Ratones Endogámicos NOD , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 1/genética , Animales , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/inmunología , Ratones , Quimiocina CXCL10/genética , Quimiocina CXCL10/metabolismo , Quimiocina CXCL10/inmunología , Islotes Pancreáticos/inmunología , Islotes Pancreáticos/metabolismo , Células T de Memoria/inmunología , Células T de Memoria/metabolismo , Modelos Animales de Enfermedad , HumanosAsunto(s)
Carcinoma Basocelular , Proteínas de Unión a Ácidos Grasos , Queratinocitos , Neoplasias Cutáneas , Humanos , Queratinocitos/metabolismo , Queratinocitos/patología , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Carcinoma Basocelular/patología , Carcinoma Basocelular/metabolismo , Carcinoma Basocelular/genética , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/genéticaRESUMEN
Fatty acid-binding protein 4 (FABP4), a fatty acid transporter that coordinates lipid metabolism, is reported to exert a tumorigenic role in certain cancers. We investigated the effects of FABP4 in the carcinogenesis of thyroid cancer. Bioinformatics data about FABP4 in thyroid cancer were collected from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA). Sixteen paired papillary thyroid cancer (PTC) tissues from Taipei Medical University (TMU) were gathered, and commercial thyroid cancer complementary (c)DNA and tissue arrays were purchased to measure FABP4 messenger (m)RNA and protein levels. By analyzing data from the GEO and TCGA, we showed that FABP4 mRNA was reduced in PTC and follicular thyroid carcinoma (FTC). In addition, a lower FABP4 mRNA level in PTC was associated with poor clinical parameters and outcomes in the TCGA database. Moreover, FABP4 transcripts and proteins were downregulated in PTC and FTC, and its mRNA expression was associated with PTC staging in clinical specimens. In the TCGA database and TMU cohort, FABP4 mRNA levels were associated with thyroglobulin (r = 0.511 and r = 0.656, respectively), thyroid peroxidase (r = 0.612 and r = 0.909, respectively), and sodium iodide symporter (r = 0.485 and r = 0.637, respectively) transcripts. In conclusion, FABP4 mRNA and protein levels were reduced in PTC and FTC, and may be used as a potential indicator for thyroid cancer evolution in clinical settings. Further, well-designed research to dissect the molecular mechanism of FABP4 in modulating thyroid carcinogenesis is needed.
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Biomarcadores de Tumor , Proteínas de Unión a Ácidos Grasos , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides , Humanos , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Cáncer Papilar Tiroideo/patología , Cáncer Papilar Tiroideo/genética , Cáncer Papilar Tiroideo/metabolismo , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/metabolismo , Masculino , Pronóstico , Femenino , Persona de Mediana Edad , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Adulto , Regulación Neoplásica de la Expresión Génica , AncianoRESUMEN
Diabetic nephropathy (DN) is one of the most important comorbidities for diabetic patients, which is the main factor leading to end-stage renal disease. Heparin analogs can delay the progression of DN, but the mechanism is not fully understood. In this study, we found that low molecular weight heparin therapy significantly upregulated some downstream proteins of the peroxisome proliferator-activated receptor (PPAR) signaling pathway by label-free quantification of the mouse kidney proteome. Through cell model verification, low molecular weight heparin can protect the heparan sulfate of renal tubular epithelial cells from being degraded by heparanase that is highly expressed in a high-glucose environment, enhance the endocytic recruitment of fatty acid-binding protein 1, a coactivator of the PPAR pathway, and then regulate the activation level of intracellular PPAR. In addition, we have elucidated for the first time the molecular mechanism of heparan sulfate and fatty acid-binding protein 1 interaction. These findings provide new insights into understanding the role of heparin in the pathogenesis of DN and developing corresponding treatments.