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 , Glucólisis

RESUMEN

Hepatocellular carcinoma (HCC) is one of the malignant tumors with high morbidity and mortality. Long non-coding RNAs (lncRNAs) are frequently dysregulated in human cancers and play an important role in the initiation and progression of HCC. Here, we investigated the expression of a new reported lncRNA495810 in our previous study by analyzing the publicly available datasets and using RT-qPCR assay. The cell proliferation experiment, cell cycle and apoptosis assay, wound healing assay, cell migration assay were used to explore the biological function of lncRNA495810 in HCC. The western blot, RNA pull down and RNA immunoprecipitation (RIP) detection were used to investigate the potential molecular mechanisms of lncRNA495810. The results demonstrated that lncRNA495810 was significantly upregulated in hepatocellular carcinoma and associated with poor prognosis of hepatocellular carcinoma patients. Moreover, it proved that lncRNA495810 promotes the proliferation and metastasis of hepatoma cells by directly binding and upregulating the expression of fatty acid-binding protein 5. These results reveal the oncogenic roles of lncRNA495810 in HCC and provide a potential therapeutic target for HCC.

RESUMEN

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.

Asunto(s)

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/metabolismo

RESUMEN

BACKGROUND: The relationship between Helicobacter pylori (H. pylori) infection and metabolic dysfunction-associated steatotic liver disease (MASLD) has attracted increased clinical attention. However, most of those current studies involve cross-sectional studies and meta-analyses, and experimental mechanistic exploration still needs to be improved. This study aimed to investigate the mechanisms by which H. pylori impacts MASLD. METHODS: We established two H. pylori-infected (Cag A positive and Cag A negative) mouse models with 16 weeks of chow diet (CD) or high-fat diet (HFD) feeding. Body weight, liver triglyceride, blood glucose, serum biochemical parameters, inflammatory factors, and insulin resistance were measured, and histological analysis of liver tissues was performed. Mouse livers were subjected to transcriptome RNA sequencing analysis. RESULTS: Although H. pylori infection could not significantly affect serum inflammatory factor levels and serum biochemical parameters in mice, serum insulin and homeostatic model assessment for insulin resistance levels increased in CD mode. In contrast, H. pylori Cag A + infection significantly aggravated hepatic pathological steatosis induced by HFD and elevated serum inflammatory factors and lipid metabolism parameters. Hepatic transcriptomic analysis in the CD groups revealed 767 differentially expressed genes (DEGs) in the H. pylori Cag A + infected group and 1473 DEGs in the H. pylori Cag A- infected group, and the "nonalcoholic fatty liver disease" pathway was significantly enriched in KEGG analysis. There were 578 DEGs in H. pylori Cag A + infection combined with the HFD feeding group and 820 DEGs in the H. pylori Cag A- infected group. DEGs in the HFD groups were significantly enriched in "fatty acid degradation" and "PPAR pathway." Exploring the effect of different Cag A statuses on mouse liver revealed that fatty acid binding protein 5 was differentially expressed in Cag A- H. pylori. DEG enrichment pathways were concentrated in the "PPAR pathway" and "fatty acid degradation." CONCLUSIONS: Clinicians are expected to comprehend the impact of H. pylori on MASLD and better understand and manage MASLD. H. pylori infection may exacerbate the development of MASLD by regulating hepatic lipid metabolism, and the H. pylori virulence factor Cag A plays a vital role in this regulation.

Asunto(s)

Hígado Graso , Infecciones por Helicobacter , Helicobacter pylori , Metabolismo de los Lípidos , Ratones Endogámicos C57BL , Transcriptoma , Animales , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/metabolismo , Metabolismo de los Lípidos/genética , Transcriptoma/genética , Hígado Graso/complicaciones , Hígado Graso/microbiología , Hígado Graso/metabolismo , Hígado Graso/genética , Hígado Graso/patología , Masculino , Dieta Alta en Grasa , Hígado/metabolismo , Hígado/patología , Resistencia a la Insulina , Perfilación de la Expresión Génica , Ratones , Enfermedades Metabólicas/microbiología , Enfermedades Metabólicas/complicaciones , Enfermedades Metabólicas/metabolismo , Enfermedades Metabólicas/patología , Enfermedades Metabólicas/genética , Redes y Vías Metabólicas/genética

Asunto(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/genética

RESUMEN

Tumor-associated macrophages (TAMs) represent a predominant cellular component within the tumor microenvironment (TME) of pancreatic neuroendocrine neoplasms (pNENs). There is a growing body of evidence highlighting the critical role of exosomes in facilitating communication between tumor cells and TAMs, thereby contributing to the establishment of the premetastatic niche. Nonetheless, the specific mechanisms through which exosomes derived from tumor cells influence macrophage polarization under hypoxic conditions in pNENs, and the manner in which these interactions support cancer metastasis, remain largely unexplored. Recognizing the capacity of exosomes to transfer miRNAs that can modify cellular behaviors, our research identified a significant overexpression of miR-4488 in exosomes derived from hypoxic pNEN cells. Furthermore, we observed that macrophages that absorbed circulating exosomal miR-4488 underwent M2-like polarization. Our investigations revealed that miR-4488 promotes M2-like polarization by directly targeting and suppressing RTN3 in macrophages. This suppression of RTN3 enhances fatty acid oxidation and activates the PI3K/AKT/mTOR signaling pathway through the interaction and downregulation of FABP5. Additionally, M2 polarized macrophages contribute to the formation of the premetastatic niche and advance pNENs metastasis by releasing MMP2, thereby establishing a positive feedback loop involving miR-4488, RTN3, FABP5, and MMP2 in pNEN cells. Together, these findings shed light on the role of exosomal miRNAs from hypoxic pNEN cells in mediating interactions between pNEN cells and intrahepatic macrophages, suggesting that miR-4488 holds potential as a valuable biomarker and therapeutic target for pNENs.

Asunto(s)

Exosomas , Neoplasias Hepáticas , Macrófagos , MicroARNs , Tumores Neuroendocrinos , Neoplasias Pancreáticas , MicroARNs/metabolismo , MicroARNs/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/genética , Exosomas/metabolismo , Humanos , Animales , Ratones , Tumores Neuroendocrinos/metabolismo , Tumores Neuroendocrinos/patología , Tumores Neuroendocrinos/genética , Macrófagos/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/genética , Línea Celular Tumoral , Ácidos Grasos/metabolismo , Oxidación-Reducción , Microambiente Tumoral , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/genética , Ratones Desnudos , Transducción de Señal

RESUMEN

Diabetic kidney disease (DKD) is one of the most common complications of diabetes, and no specific drugs are clinically available. We have previously demonstrated that inhibiting microsomal prostaglandin E synthase-2 (mPGES-2) alleviated type 2 diabetes by enhancing ß cell function and promoting insulin production. However, the involvement of mPGES-2 in DKD remains unclear. Here, we aimed to analyze the association of enhanced mPGES-2 expression with impaired metabolic homeostasis of renal lipids and subsequent renal damage. Notably, global knockout or pharmacological blockage of mPGES-2 attenuated diabetic podocyte injury and tubulointerstitial fibrosis, thereby ameliorating lipid accumulation and lipotoxicity. These findings were further confirmed in podocyte- or tubule-specific mPGES-2-deficient mice. Mechanistically, mPGES-2 and Rev-Erbα competed for heme binding to regulate fatty acid binding protein 5 expression and lipid metabolism in the diabetic kidney. Our findings suggest a potential strategy for treating DKD via mPGES-2 inhibition.

Asunto(s)

Nefropatías Diabéticas , Metabolismo de los Lípidos , Miembro 1 del Grupo D de la Subfamilia 1 de Receptores Nucleares , Podocitos , Prostaglandina-E Sintasas , Transducción de Señal , Animales , Humanos , Masculino , Ratones , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Nefropatías Diabéticas/tratamiento farmacológico , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Fibrosis , Riñón/patología , Riñón/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Ratones Endogámicos C57BL , Ratones Noqueados , Miembro 1 del Grupo D de la Subfamilia 1 de Receptores Nucleares/metabolismo , Miembro 1 del Grupo D de la Subfamilia 1 de Receptores Nucleares/genética , Podocitos/metabolismo , Podocitos/patología , Podocitos/efectos de los fármacos , Prostaglandina-E Sintasas/metabolismo , Prostaglandina-E Sintasas/genética , Transducción de Señal/efectos de los fármacos

RESUMEN

BACKGROUND: Polycystic ovary syndrome (PCOS) is one of the most complex endocrine disorders in women of reproductive age. Abnormal proliferation of granulosa cells (GCs) is an important cause of PCOS. This study aimed to explore the role of fatty acid-binding protein 5 (FABP5) in granulosa cell (GC) proliferation in polycystic ovary syndrome (PCOS) patients. METHODS: The FABP5 gene, which is related to lipid metabolism, was identified through data analysis of the gene expression profiles of GSE138518 from the Gene Expression Omnibus (GEO) database. The expression levels of FABP5 were measured by quantitative real-time PCR (qRT‒PCR) and western blotting. Cell proliferation was evaluated with a cell counting kit-8 (CCK-8) assay. Western blotting was used to assess the expression of the proliferation marker PCNA, and immunofluorescence microscopy was used to detect Ki67 expression. Moreover, lipid droplet formation was detected with Nile red staining, and qRT‒PCR was used to analyze fatty acid storage-related gene expression. RESULTS: We found that FABP5 was upregulated in ovarian GCs obtained from PCOS patients and PCOS mice. FABP5 knockdown suppressed lipid droplet formation and proliferation in a human granulosa-like tumor cell line (KGN), whereas FABP5 overexpression significantly enhanced lipid droplet formation and KGN cell proliferation. Moreover, we determined that FABP5 knockdown inhibited PI3K-AKT signaling by suppressing AKT phosphorylation and that FABP5 overexpression activated PI3K-AKT signaling by facilitating AKT phosphorylation. Finally, we used the PI3K-AKT signaling pathway inhibitor LY294002 and found that the facilitation of KGN cell proliferation and lipid droplet formation induced by FABP5 overexpression was inhibited. In contrast, the PI3K-AKT signaling pathway agonist SC79 significantly rescued the suppression of KGN cell proliferation and lipid droplet formation caused by FABP5 knockdown. CONCLUSIONS: FABP5 promotes active fatty acid synthesis and excessive proliferation of GCs by activating PI3K-AKT signaling, suggesting that abnormally high expression of FABP5 in GCs may be a novel biomarker or a research target for PCOS treatment.

Asunto(s)

Proteínas de Unión a Ácidos Grasos , MicroARNs , Síndrome del Ovario Poliquístico , Animales , Femenino , Humanos , Ratones , Proliferación Celular/genética , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Células de la Granulosa/metabolismo , MicroARNs/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Síndrome del Ovario Poliquístico/genética , Síndrome del Ovario Poliquístico/metabolismo , Síndrome del Ovario Poliquístico/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo

RESUMEN

Fatty acid binding protein 5 (FABP5) is an intracellular chaperone of fatty acid molecules that regulates lipid metabolism and cell growth. However, its role in intestinal inflammation remains enigmatic. Through examination of human tissue samples and single-cell data, we observed a significant upregulation of FABP5 within the mucosa of patients afflicted with ulcerative colitis (UC) and Crohn's disease (CD), predominantly localized in intestinal macrophages. Herein, we investigate the regulation of FABP5-IN-1, a FABP5 inhibitor, on various cells of the gut in an inflammatory environment. Our investigations confirmed that FABP5 ameliorates DSS-induced colitis in mice by impeding the differentiation of macrophages into M1 macrophages in vitro and in vivo. Furthermore, following FABP5-IN-1 intervention, we observed a notable restoration of intestinal goblet cells and tuft cells, even under inflammatory conditions. Additionally, FABP5-IN-1 exhibits a protective effect against DSS-induced colitis by promoting the polarization of macrophages towards the M2 phenotype in vivo. In summary, FABP5-IN-1 confers protection against DSS-induced acute colitis through a multifaceted approach, encompassing the reduction of inflammatory macrophage infiltration, macrophage polarization, regulating Th17/Treg cells to play an anti-inflammatory role in IBD. The implications for IBD are underscored by the comprehensive in vivo and in vitro experiments presented in this article, thereby positioning FABP5 as a promising and novel therapeutic target for the treatment of IBD.

Asunto(s)

Colitis Ulcerosa , Colitis , Enfermedades Inflamatorias del Intestino , Humanos , Animales , Ratones , Enfermedades Inflamatorias del Intestino/inducido químicamente , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/metabolismo , Colitis/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Macrófagos , Antiinflamatorios/farmacología , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Colon , Activación de Macrófagos , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo

RESUMEN

OBJECTIVE: Osteoarthritis (OA) is often accompanied by debilitating pain that is refractory to available analgesics due in part to the complexity of signaling molecules that drive OA pain and our inability to target these in parallel. Fatty acid binding protein 5 (FABP5) is a lipid chaperone that regulates inflammatory pain; however, its contribution to OA pain has not been characterized. DESIGN: This combined clinical and pre-clinical study utilized synovial tissues obtained from subjects with end-stage OA and rats with monoiodoacetate-induced OA. Cytokine and chemokine release from human synovia incubated with a selective FABP5 inhibitor was profiled with cytokine arrays and ELISA. Immunohistochemical analyses were conducted for FABP5 in human and rat synovium. The efficacy of FABP5 inhibitors on pain was assessed in OA rats using incapacitance as an outcome. RNA-seq was then performed to characterize the transcriptomic landscape of synovial gene expression in OA rats treated with FABP5 inhibitor or vehicle. RESULTS: FABP5 was expressed in human synovium and FABP5 inhibition reduced the secretion of pronociceptive cytokines (interleukin-6 [IL6], IL8) and chemokines (CCL2, CXCL1). In rats, FABP5 was upregulated in the OA synovium and its inhibition alleviated incapacitance. The transcriptome of the rat OA synovium exhibited >6000 differentially expressed genes, including the upregulation of numerous pronociceptive cytokines and chemokines. FABP5 inhibition blunted the upregulation of the majority of these pronociceptive mediators. CONCLUSIONS: FABP5 is expressed in the OA synovium and its inhibition suppresses pronociceptive signaling and pain, indicating that FABP5 inhibitors may constitute a novel class of analgesics to treat OA.

Asunto(s)

Citocinas , Osteoartritis , Humanos , Ratas , Animales , Citocinas/metabolismo , Osteoartritis/metabolismo , Dolor/metabolismo , Quimiocinas/metabolismo , Membrana Sinovial/metabolismo , Analgésicos , Proteínas de Unión a Ácidos Grasos/genética

RESUMEN

AIMS: To explore the accumulation of lipid droplets (LDs) and its relationship with lipid metabolism, and epithelial-mesenchymal transition (EMT) in the carcinogenesis processes in the oral cavity. METHODS: LDs were stained by oil red O. Forty-eight oral squamous cell carcinomas (OSCC), 78 oral potentially malignant disorders (OPMDs) and 25 normal tissue sections were included to explore the LDs surface protein caveolin-2 and perilipin-3, lipid metabolism-related molecule FABP5 and EMT biomarker E-cadherin expression by immunohistochemical staining. RESULTS: The accumulation of LDs was observed in OPMDs and OSCCs compared with normal tissues (p<0.05). In general, an increasing trend of caveolin-2, perilipin-3 and FABP5 expression was detected from the normal to OPMDs to OSCC groups (p<0.05). Additionally, caveolin-2, perilipin-3 and FABP5 expression were positively correlated with epithelial dysplasia in OPMDs, whereas E-cadherin positivity was negatively correlated with histopathological grade in both OPMDs and OSCC, respectively. A negative correlation of caveolin-2 (p<0.01, r =-0.1739), and FABP5 (p<0.01, r =-0.1880) with E-cadherin expression was detected. The caveolin-2 (p<0.0001, r=0.2641) and perilipin-3 (p<0.05, r=0.1408) staining was positively correlated with FABP5. Increased caveolin-2 expression was related to local recurrence and worse disease-free survival (p<0.05). CONCLUSION: In the oral epithelial carcinogenesis process, LDs begin to accumulate early in the precancerous stage. LDs may be the regulator of FABP5-associated lipid metabolism and may closely related to the process of EMT; caveolin-2 could be the main functional protein.

RESUMEN

Herein, PC12 cells were applied to detect the impact of progesterone under oxygen glucose deprivation/reperfusion (OGD/R) stimulation. The cell proliferation of PC12 cells was evaluated by cell counting kit-8 assay, and the concentrations of MDA, ROS and SOD were examined by their corresponding Enzyme Linked Immunosorbent Assay kits. The invasion and migration properties of PC12 cells were evaluated by transwell and wound healing assays, respectively. The expression patterns of related genes were evaluated by western blot and qPCR. Under OGD/R stimulation, progesterone treatment could elevate the viability of PC12 cells, reduce the levels of MDA and ROS, and elevate the concentration of SOD. Moreover, progesterone treatment could strengthen the invasion and migration abilities of PC12 cells under OGD/R condition, as well as decrease the apoptosis and inflammation. FABP5 expression was significantly increased in PC12 cells under OGD/R stimulation, which was reversed after progesterone stimulation. Under OGD/R stimulation, the protective effects of progesterone on PC12 cells were strengthened after si-FABP5 treatment. The protein levels of TLR4, p-P65 NF-κB, and P65 NF-κB in OGD/R-induced PC12 cells were increased, which were inhibited after progesterone treatment. Progesterone exerted protective effects on PC12 cells by targeting FABP5 under OGD/R stimulation.

Asunto(s)

FN-kappa B , Daño por Reperfusión , Ratas , Animales , FN-kappa B/metabolismo , Oxígeno/metabolismo , Células PC12 , Receptor Toll-Like 4/metabolismo , Progesterona/farmacología , Especies Reactivas de Oxígeno/metabolismo , Glucosa/metabolismo , Daño por Reperfusión/metabolismo , Transducción de Señal , Reperfusión , Superóxido Dismutasa , Apoptosis

RESUMEN

Fatty acid­binding protein 5 (FABP5) and androgen receptor (AR) are critical promoters of prostate cancer. In the present study, the effects of knocking out the FABP5 or AR genes on malignant characteristics of prostate cancer cells were investigated, and changes in the expression of certain key proteins in the FABP5 (or AR)­peroxisome proliferator activated receptor­Î³ (PPARγ)­vascular endothelial growth factor (VEGF) signaling pathway were monitored. The results obtained showed that FABP5­ or AR­knockout (KO) led to a marked suppression of the malignant characteristics of the cells, in part, through disrupting this signaling pathway. Moreover, FABP5 and AR are able to interact with each other to regulate this pathway, with FABP5 controlling the dominant AR splicing variant 7 (ARV7), and AR, in return, regulates the expression of FABP5. Comparisons of the RNA profiles revealed the existence of numerous differentially expressed genes (DEGs) comparing between the parental and the FABP5­ or AR­KO cells. The six most abundant changes in DEGs were found to be attributable to the transition from androgen­responsive to androgen­unresponsive, castration­resistant prostate cancer (CRPC) cells. These findings have provided novel insights into the complex molecular pathogenesis of CRPC cells, and have demonstrated that interactions between FABP5 and AR contribute to the transition of prostate cancer cells to an androgen­independent state. Moreover, gene enrichment analysis revealed that the most highly enriched biological processes associated with the DEGs included those responsive to fatty acids, cholesterol and sterol biosynthesis, as well as to lipid and fatty acid transportation. Since these pathways regulated by FABP5 or AR may be crucial in terms of transducing signals for cancer cell progression, targeting FABP5, AR and their associated pathways, rather than AR alone, may provide a new avenue for the development of therapeutic strategies geared towards suppressing the malignant progression to CRPC cells.

Asunto(s)

Neoplasias de la Próstata Resistentes a la Castración , Receptores Androgénicos , Masculino , Humanos , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Andrógenos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo

RESUMEN

BACKGROUND AND PURPOSE: Because of cervical cancer (CC) metastasis, the prognosis of diagnosed patients is poor. However, the molecular mechanisms and therapeutic approach for metastatic CC remain elusive. EXPERIMENTAL APPROACH: In this study, we first evaluated the effect of resveratrol (RSV) on CC cell migration and metastasis. Via an activity-based protein profiling (ABPP) approach, a photoaffinity probe of RSV (RSV-P) was synthesized, and the protein targets of RSV in HeLa cells were identified. Based on target information and subsequent in vivo and in vitro validation experiments, we finally elucidated the mechanism of RSV corresponding to its antimetastatic activity. KEY RESULTS: The results showed that RSV concentration-dependently suppressed CC cell migration and metastasis. A list of proteins was identified as the targets of RSV, through the ABPP approach with RSV-P, among which fatty acid binding protein 5 (FABP5) attracted our attention based on The Cancer Genome Atlas (TCGA) database analysis. Subsequent knockout and overexpression experiments confirmed that RSV directly interacted with FABP5 to inhibit fatty acid transport into the nucleus, thereby suppressing downstream matrix metalloproteinase-2 (MMP2) and matrix metalloproteinase-9 (MMP9) expression, thus inhibiting CC metastasis. CONCLUSIONS AND IMPLICATIONS: Our study confirmed the key role of FABP5 in CC metastasis and provided important target information for the design of therapeutic lead compounds for metastatic CC.

Asunto(s)

Proteínas de Unión a Ácidos Grasos , Ácidos Grasos , Resveratrol , Neoplasias del Cuello Uterino , Humanos , Resveratrol/farmacología , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/metabolismo , Femenino , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/antagonistas & inhibidores , Ácidos Grasos/metabolismo , Animales , Movimiento Celular/efectos de los fármacos , Células HeLa , Núcleo Celular/metabolismo , Núcleo Celular/efectos de los fármacos , Metástasis de la Neoplasia , Ratones , Ratones Desnudos , Ratones Endogámicos BALB C , Metaloproteinasa 9 de la Matriz/metabolismo , Relación Dosis-Respuesta a Droga

RESUMEN

BACKGROUND: Atherosclerosis (AS) is a critical pathological event during the progression of cardiovascular diseases. It exhibits fibrofatty lesions on the arterial wall and lacks effective treatment. N6-methyladenosine (m6A) is the most common modification of eukaryotic RNA and plays an important role in regulating the development and progression of cardiovascular diseases. However, the role of m6A modification in AS remains largely unknown. Therefore, in this study, we explored the transcriptome distribution of m6A modification in AS and its potential mechanism. METHODS: Methylation Quantification Kit was used to detect the global m6A levels in the aorta of AS mice. Western blot was used to analyze the protein level of methyltransferases. Methylated RNA immunoprecipitation with next-generation sequencing (MeRIP-seq) and RNA sequencing (RNA-seq) were used to obtain the first transcriptome range analysis of the m6A methylene map in the aorta of AS mice, followed by bioinformatics analysis. qRT-PCR and MeRIP-qRT-PCR were used to measure the mRNA and m6A levels in target genes. RESULTS: The global m6A and protein levels of methyltransferase METTL3 were significantly increased in the aorta of AS mice. However, the protein level of demethylase ALKBH5 was significantly decreased. Through MeRIP-seq, we obtained m6A methylation maps in AS and control mice. In total, 26,918 m6A peaks associated with 13,744 genes were detected in AS group, whereas 26,157 m6A peaks associated with 13,283 genes were detected in the control group. Peaks mainly appeared in the coding sequence (CDS) regions close to the stop codon with the RRACH motif. Moreover, functional enrichment analysis demonstrated that m6A-containing genes were significantly enriched in AS-relevant pathways. Interestingly, a negative correlation between m6A methylation abundance and gene expression level was found through the integrated analysis of MeRIP-seq and RNA-seq data. Among the m6A-modified genes, a hypo-methylated but up-regulated (hypo-up) gene Fabp5 may be a potential biomarker of AS. CONCLUSIONS: Our study provides transcriptome-wide m6A methylation for the first time to determine the association between m6A modification and AS progression. Our study lays a foundation for further exploring the pathogenesis of AS and provides a new direction for the treatment of AS.

Asunto(s)

Enfermedades Cardiovasculares , Transcriptoma , Ratones , Animales , Metilación , ARN/metabolismo

RESUMEN

One of the hallmarks of intractable psoriasis is neutrophil infiltration in skin lesions. However, detailed molecular mechanisms of neutrophil chemotaxis and activation remain unclear. Here, we demonstrate a significant upregulation of epidermal fatty acid binding protein (E-FABP, FABP5) in the skin of human psoriasis and psoriatic mouse models. Genetic deletion of FABP5 in mice by global knockout and keratinocyte conditional (Krt6a-Cre) knockout, but not myeloid cell conditional (LysM-Cre) knockout, attenuates psoriatic symptoms. Immunophenotypic analysis shows that FABP5 deficiency specifically reduces skin recruitment of Ly6G+ neutrophils. Mechanistically, activated keratinocytes produce chemokines and cytokines that trigger neutrophil chemotaxis and activation in an FABP5-dependent manner. Proteomic analysis further identifies that FABP5 interacts with valosin-containing protein (VCP), a key player in NF-κB signaling activation. Silencing of FABP5, VCP, or both inhibits NF-κB/neutrophil chemotaxis signaling. Collectively, these data demonstrate dysregulated FABP5 as a molecular mechanism promoting NF-κB signaling and neutrophil infiltration in psoriasis pathogenesis.

Asunto(s)

Neutrófilos , Psoriasis , Animales , Humanos , Ratones , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Inflamación/metabolismo , Queratinocitos/metabolismo , Neutrófilos/metabolismo , FN-kappa B/metabolismo , Proteómica , Psoriasis/patología , Proteína que Contiene Valosina/metabolismo

RESUMEN

Background: While acute inflammation serves essential functions in maintaining tissue homeostasis, chronic inflammation is causally linked to many diseases. Macrophages are a major cell-type that orchestrates inflammatory processes. During inflammation, macrophages undergo polarization and activation, thereby mobilizing pro-inflammatory and anti-inflammatory transcriptional programs that regulate ensuing macrophage functions. Fatty acid binding protein 5 (FABP5) is a lipid chaperone that is highly expressed in macrophages. FABP5 deletion is implicated in driving macrophages towards an anti-inflammatory phenotype, yet the signaling pathways regulated by macrophage FABP5 have not been systematically profiled. Herein, we leveraged proteomic and phosphoproteomic approaches to characterize pathways modulated by FABP5 in M1 and M2 polarized bone marrow derived macrophages (BMDMs). Results: Stable isotope labeling by amino acids (SILAC) based analysis of M1 and M2 polarized wild-type (WT) and FABP5 knockout (KO) BMDMs revealed numerous differentially regulated proteins and phosphoproteins. FABP5 deletion impacted several downstream pathways associated with inflammation, cytokine production, oxidative stress, and kinase activity. Kinase enrichment analysis based on phosphorylated sites revealed key kinases, including members of the GRK family, that were altered in FABP5 KO BMDMs. Reactive oxygen species (ROS) levels were elevated in M1 polarized KO macrophages, consistent with the differential protein expression profiles. Conclusions: This study represents a comprehensive characterization of the impact of FABP5 deletion upon the proteomic and phosphoproteomic landscape of M1 and M2 polarized BMDMs. Loss of FABP5 altered multiple pathways implicated in inflammatory responses and macrophage function. This work provides a foundation for future studies seeking to investigate the therapeutic potential of FABP5 inhibition in pathophysiological states resulting from dysregulated inflammatory signaling.

RESUMEN

The process of post-transcriptional regulation has been recognized to be significantly impacted by the presence of N6-methyladenosine (m6A) modification. As an m6A demethylase, ALKBH5 has been shown to contribute to the progression of different cancers by increasing expression of several oncogenes. Hence, a better understanding of the key targets of ALKBH5 in cancer cells could potentially lead to the development of new therapeutic targets. However, the specific role of ALKBH5 in pancreatic neuroendocrine neoplasms (pNENs) remains largely unknown. Here, we demonstrated that ALKBH5 was up-regulated in pNENs and played a critical role in tumor growth and lipid metabolism. Mechanistically, ALKBH5 over-expression was found to increase the expression of FABP5 in an m6A-IGF2BP2 dependent manner, leading to disorders in lipid metabolism. Additionally, ALKBH5 was found to activate PI3K/Akt/mTOR signaling pathway, resulting in enhanced lipid metabolism and proliferation abilities. In conclusion, our study uncovers the ALKBH5/IGF2BP2/FABP5/mTOR axis as a mechanism for aberrant m6A modification in lipid metabolism and highlights a new molecular basis for the development of therapeutic strategies for pNENs treatment.

Asunto(s)

Metabolismo de los Lípidos , Neoplasias Pancreáticas , Humanos , Metabolismo de los Lípidos/genética , Fosfatidilinositol 3-Quinasas , Neoplasias Pancreáticas/genética , Adenosina , Serina-Treonina Quinasas TOR , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión al ARN , Desmetilasa de ARN, Homólogo 5 de AlkB/genética

RESUMEN

BACKGROUND: Extramammary Paget's disease (EMPD) is a rare cutaneous malignant tumor with a high recurrence rate after surgery. However, the genetic and epigenetic alterations underlying its pathogenesis remain unknown. DNA methylation is an important epigenetic modification involved in many biological processes. METHODS: In this study, enzymatic methyl-sequencing (EM-seq) technique was used to investigate the landscape of genome-wide DNA methylation from three pairs of tumor tissues and adjacent tissues of patients with EMPD. Additionally, we conducted histopathological examinations to assess the expression of fatty acid-binding protein 5 (FABP5) in another three paired samples from EMPD patients. RESULTS: The cluster analysis showed the good quality of the samples. A differential methylation region (DMR) heat map was used to quantitatively characterize genome-wide methylation differences between tumors and controls. Global DNA methylation level is lower in EMPD tissue compared to matched controls, indicating that DNA methylation discriminates between tumor and normal skin. And the top hypomethylation gene on the promoter region in tumor tissues was FABP5 on chromosome 8 with 38.44% decreased median methylation. We next identified the expression of FABP5 in paired tumors and adjacent tissues in three additional patients with EMPD. Immunofluorescence results showed FABP5 highly expressed in tumor tissues and co-located with CK7, CK20 and EMA. GO and KEGG enrichment analysis showed DMR genes on promoter are mainly enriched in the calcium ion transport, GTPase mediated signal transduction, Rap1 signaling pathway and GnRH signaling pathway. CONCLUSION: Taken together, our findings provide the first description of the whole genome methylation map of EMPD and identify FABP5 as a pathogenic target of EMPD.

Asunto(s)

Enfermedad de Paget Extramamaria , Neoplasias Cutáneas , Humanos , Enfermedad de Paget Extramamaria/genética , Enfermedad de Paget Extramamaria/metabolismo , Enfermedad de Paget Extramamaria/patología , Metilación , Neoplasias Cutáneas/patología , Epigénesis Genética/genética , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo

RESUMEN

Macrophages (MΦs) protect multiple myeloma (MM) cells from chemotherapy-induced apoptosis, and interleukin-10 (IL-10) is frequently elevated in the MM microenvironment. However, the role of IL-10 in MΦ-induced tumor chemotherapy resistance has not yet been clarified. In the present study, bone marrow-derived MΦs were treated with IL-10 (IL10-MΦs), and IL10-MΦ-induced MM chemotherapy resistance was evaluated. IL-10 promoted MΦ-mediated resistance to MM chemotherapy. In addition, IL-10 treatment increased lipid accumulation and fatty acid ß-oxidation in MΦs. Mechanistically, IL-10 increased fatty acid binding protein 5 (FABP5) expression in MΦs, and targeting FABP5 decreased MM chemotherapy resistance induced by IL10-MΦs in vitro and enhanced chemotherapeutic efficacy in vivo. Inhibition of FABP5 decreased the expression of Carnitine Palmitoyltransferase 1A (CPT1A) in IL10-MΦs. In addition, inhibition of CPT1A in IL10-MΦs decreased IL10-MΦ-mediated MM chemotherapy resistance. Peroxisome proliferator-activated receptor γ (PPARγ) is upstream of FABP5 signaling. Inhibition of PPARγ in IL10-MΦs decreased IL10-MΦ-mediated MM chemotherapy resistance in vitro. Collectively, our work indicates that IL-10 enhances MΦ-mediated MM chemotherapy resistance via FABP5 signaling and targeting FABP5 has potentially important clinical implications.