FGFR1 Expression Research Articles

Spatial distribution and functional relevance of FGFR1 and FGFR2 expression for glioblastoma tumor invasion

Glioblastoma is the most lethal brain cancer in adults. These incurable tumors are characterized by profound heterogeneity, therapy resistance, and diffuse infiltration. These traits have been linked to cancer stem cells, which are important for glioblastoma tumor progression and recurrence. The fibroblast growth factor receptor 1 (FGFR1) signaling pathway is a known regulator of therapy resistance and cancer stemness in glioblastoma. FGFR1 expression shows intertumoral heterogeneity and higher FGFR1 expression is associated with a significantly poorer survival in glioblastoma patients. The role of FGFR1 in tumor invasion has been studied in many cancers, but whether and how FGFR1 mediates glioblastoma invasion remains to be determined. Here, we investigated the distribution and functional relevance of FGFR1 and FGFR2 in human glioblastoma xenograft models. We found FGFR1, but not FGFR2, expressed in invasive glioblastoma cells. Loss of FGFR1, but not FGFR2, significantly reduced cell migration in vitro and tumor invasion in human glioblastoma xenografts. Comparative analysis of RNA-sequencing data of FGFR1 and FGFR2 knockdown glioblastoma cells revealed a FGFR1-specific gene regulatory network associated with tumor invasion. Our study reveals new gene candidates linked to FGFR1-mediated glioblastoma invasion.

Taraxasterol suppresses the proliferation and tumor growth of androgen-independent prostate cancer cells through the FGFR2-PI3K/AKT signaling pathway

Prostate cancer (PCa) is prevalent among older men and difficult to survive after metastasis. It is urgent to find new drugs and treatments. Several studies show that taraxasterol (TAX) has important anti-inflammatory, anti-oxidative and anti-tumor effects. However, the function and mechanisms of TAX in PCa remain unclear. Here, we found that TAX could significantly suppress the viability and growth of androgen-independent PCa cells and down-regulate the expression of c-Myc and cyclin D1 in vitro. Mechanistically, PI3K/AKT signaling pathway was weakened and the expression of FGFR2 was reduced after TAX treatment in androgen-independent PCa cells. Moreover, TAX evidently inhibited the tumor growth in nude mice and the expression of c-Myc, cyclin D1, p-AKT and FGFR2 were down-regulated in xenograft tumor. These results indicate that TAX suppresses the proliferation of androgen-independent PCa cells via inhibiting the activation of PI3K/AKT signaling pathway and the expression of FGFR2, which means TAX may be a novel anti-tumor agent for later PCa treatment.

FGFR1Pred: an artificial intelligence-based model for predicting fibroblast growth factor receptor 1 inhibitor.

Fibroblast growth factor receptors (FGFRs) are a family of cell surface receptors that bind to fibroblast growth factor (FGF) and mediate various cellular functions (translocating proteins, tissue repair, cell proliferation, development, and differentiation) through complex signaling pathways. The FGFR1 growth receptor is essential in the pathogenesis of numerous malignancies, including but not limited to breast cancer, bladder cancer, hepatocellular carcinoma (HCC), and cholangiocarcinoma. The higher levels of FGFR1 expression on the surface of cancer cells cause overly active signaling, which leads to rapid cell proliferation, resulting in a high spread of cancer cells. The kinases that FGFR1 activates migrate across the cell nucleus, activating genes and kinase proteins necessary for the growth and survival of cancerous cells. Therefore, FGFR1 targeting shows therapeutic promise in some diseases, including cancer. Inhibitors of FGFR1s are being developed and studied for their potential to block aberrant FGFR1 signaling and inhibit cancer growth. Since the discovery of new FGFR1 inhibitors in the laboratory is difficult, expensive, time-consuming, and labor-intensive, only a small number of FGFR1 inhibitors have been approved by the FDA for use in the treatment of cancer. To accelerate drug discovery by efficiently exploring the vast chemical space, and identifying potential candidates with higher accuracy and reduced cost, we developed artificial intelligence (AI)-based prediction models for FGFR1 inhibitors using a dataset of 2356 chemical compounds. Four machine learning (ML) algorithms (SVM, RF, k-NN, and ANN) were used to train different prediction models based on molecular descriptors (1D and 2D, with and without molecular fingerprints). Among all trained models, the random forest (RF)-based prediction model achieved the highest accuracy on the training (98.9%), test (89.8%), and external test (90.3%) datasets. The developed inhibitor prediction model (FGFR1Pred) provides a valuable tool for identifying potential FGFR1 inhibitors, expediting the drug discovery process and ultimately facilitating the development of new therapeutics. The model is made available at https://github.com/PGlab-NIPER/FGFR1Pred.git.

Tackling FGFR3-driven bladder cancer with a promising synergistic FGFR/HDAC targeted therapy

Bladder cancer (BC) is one of the most prevalent malignancies worldwide and FGFR3 alterations are particularly common in BC. Despite approval of erdafitinib, durable responses for FGFR inhibitors are still uncommon and most patients relapse to metastatic disease. Given the necessity to discover more efficient therapies for BC, herein, we sought to explore promising synergistic combinations for BC with FGFR3 fusions. Our studies confirmed the synergy between FGFR and HDAC inhibitors in vitro and demonstrated its benefits in vivo. Mechanistic studies revealed that quisinostat can downregulate FGFR3 expression by suppressing FGFR3 translation. Additionally, quisinostat can also sensitize BC cells to erdafitinib by downregulating HDGF. Furthermore, the synergy was also confirmed in BC cells with FGFR3 S249C. This study discovers a new avenue for treatment of FGFR3-driven BC and uncovers new mechanistic insights. These preclinical studies pave the way for a direct translation of this combination to early phase clinical trials.

Influence of FGF4 and BMP4 on FGFR2 dynamics during the segregation of epiblast and primitive endoderm cells in the pre-implantation mouse embryo.

Specification of the epiblast (EPI) and primitive endoderm (PE) in the mouse embryo involves fibroblast growth factor (FGF) signaling through the RAS/MAP kinase pathway. FGFR1 and FGFR2 are thought to mediate this signaling in the inner cell mass (ICM) of the mouse blastocyst and BMP signaling can also influence PE specification. In this study, we further explored the dynamics of FGFR2 expression through an enhanced green fluorescent protein (eGFP) reporter mouse line (FGFR2-eGFP). We observed that FGFR2-eGFP is present in the late 8-cell stage; however, it is absent or reduced in the ICM of early blastocysts. We then statistically correlated eGFP expression with PE and EPI markers GATA6 and NANOG, respectively. We detected that eGFP is weakly correlated with GATA6 in early blastocysts, but this correlation quickly increases as the blastocyst develops. The correlation between eGFP and NANOG decreases throughout blastocyst development. Treatment with FGF from the morula stage onwards did not affect FGFR2-eGFP presence in the ICM of early blastocysts; however, late blastocysts presented FGFR2-eGFP in all cells of the ICM. BMP treatment positively influenced FGFR2-eGFP expression and reduced the number of NANOG-positive cells in late blastocysts. In conclusion, FGFR2 is not strongly associated with PE precursors in the early blastocyst, but it is highly correlated with PE cells as blastocyst development progresses, consistent with the proposed role for FGFR2 in maintenance rather than initiating the PE lineage.

Antitumor effect of luteolin proven by patient-derived organoids of gastric cancer.

Luteolin (Lut) has been shown to inhibit gastric cancer (GC); however, its efficacy compared to other clinical drugs has not been examined in human samples. This study aimed to elucidate the antitumor activity of Lut in GC patient-derived organoids (PDOs). PDOs were established from GC cancer tissues, and the characterization of tissues and PDOs was performed using whole-exome sequencing. Drug sensitivity tests were performed by treating PDOs with Lut, norcantharidin (NCTD), and carboplatin (CP). RNA sequencing of PDOs was performed to elucidate the antitumor mechanism of Lut, which was further verified in three GC cell lines. Eleven PDOs were successfully constructed, and were highly consistent with the pathophysiology and genetic changes in the corresponding tumors. The IC50s of Lut, NCTD, and CP of PDOs were 27.19, 23.9, and 37.87 μM, respectively. Lut treatment upregulated FOXO3, DUSP1, and CDKN1A expression and downregulated IL1R1 and FGFR4 expression in GC cell lines, which was consistent with the results of PDOs. We demonstrate that Lut exerted stronger antitumor effects than CP, but a similar effect to that of NCTD, which was obtained in an in vitro PDO system. Additionally, Lut exerted varying degrees of antitumor effects against the PDOs, thereby indicating that PDO may be a useful preclinical drug screening tool for personalized treatment.

DNMT3B activates FGFR3-mediated endoplasmic reticulum stress by regulating PTPN2 promoter methylation to promote the development of atherosclerosis.

Endoplasmic reticulum (ER) stress is closely associated with atherosclerosis (AS). Nevertheless, the regulatory mechanism of ER stress in endothelial cells during AS progression is unclear. Here, the role and regulatory mechanism of DNA (cytosine-5-)- methyltransferase 3 beta (DNMT3B) in ER stress during AS progression were investigated. ApoE-/- mice were fed with high fat diet to construct AS model in vivo. HE and Masson staining were performed to analyze histopathological changes and collagen deposition. HUVECs stimulated by ox-LDL were used as AS cellular model. Cell apoptosis was examined using flow cytometry. DCFH-DA staining was performed to examine ROS level. The levels of pro-inflammatory cytokines were assessed using ELISA. In addition, MSP was employed to detect PTPN2 promoter methylation level. Our results revealed that DNMT3B and FGFR3 were significantly upregulated in AS patient tissues, whereas PTPN2 was downregulated. PTPN2 overexpression attenuate ox-LDL-induced ER stress, inflammation and apoptosis in HUVECs and ameliorated AS symptoms in vivo. PTPN2 could suppress FGFR3 expression in ox-LDL-treated HUVECs, and FGFR3 knockdown inhibited ER stress to attenuate ox-LDL-induced endothelial cell apoptosis. DNMT3B could negatively regulate PTPN2 expression and positively FGFR2 expression in ox-LDL-treated HUVECs; DNMT3B activated FGFR2 expression by increasing PTPN2 promoter methylation level. DNMT3B downregulation repressed ox-LDL-induced ER stress, inflammation and cell apoptosis in endothelial cells, which was reversed by PTPN2 silencing. DNMT3B activated FGFR3-mediated ER stress by increasing PTPN2 promoter methylation level and suppressed its expression, thereby boosting ER stress to facilitate AS progression.

Mung bean seed coat water extract restores insulin sensitivity via upregulation of antioxidant defense system and downregulation of inflammation in insulin-resistant HepG2 cells

Insulin resistance is the main cause of type 2 diabetes. Mung bean possesses many health benefits mainly related to polyphenols, which is abundant in mung bean seed coat. Total phenolic content in mung bean seed coat water extract (MSWE) was 0.62 ± 0.00 mg gallic acid equivalents (GAE)/g extract with antioxidant activity (IC50 = 0.16 ± 0.01 mg/mL). Vitexin and isovitexin were the major flavonoids in MSWE. MSWE increased cellular glucose uptake and reduced intracellular reactive oxygen species (ROS) in insulin-resistant HepG2 cells. MSWE upregulated IRS-1, FGFR1, PI3K, and AKT expression, while downregulated FOXO1, PEPCK, and GSK3. MSWE modulated the expression of antioxidant genes including NRF2, KEAP1, HO-1, and NQO1. MSWE also downregulated genes related to inflammation (IL-6, IL-1β, TNF-α, PTP1B, and p53). In conclusion, MSWE restored insulin sensitivity possibly through the reduction of ROS-associated inflammation by regulating GSK3/NRF2/KEAP1, downregulating PTP-1B and p53, as well as upregulating IRS-1/FGFR1/PI3K/AKT in insulin-resistant HepG2 cells.

Screening the Chemical Composition and Bioactivity of Cerasus serrulata Flower Extracts Using Two Extraction Methods

Background Cerasus serrulata has an excellent antioxidative, antibacterial, and anti-alopecia effect, but its active ingredients and the underlying mechanism are currently unclear, in addition to the fact that the active products vary with the extraction methods. Aim Therefore, this study aims to clarify the active components and antioxidative property of C. serrulata extracted by two different methods (low-temperature vacuum extraction and ethanol extraction) and explore its potential biofunction. Materials and Methods First, the compositions in extracts were characterized by gas chromatographic mass spectrometry (GC-MS) and liquid chromatography-mass spectrography (LC-MS). Then, the antioxidative activity of both extracts was evaluated using free radical scavenging assay (ABTS) and ORAC. Next, the antibacterial activity of both extracts was measured via a bacteriostatic circle experiment. The anti-alopecia effects of both extracts were studied using a mouse model of alopecia. The hematoxylin and eosin (H&E) staining was used to evaluate hair follicles; vascular endothelial-derived growth factor (VEGF) and interleukin-6 (IL-6) expression in mouse skin were evaluated by immunohistochemistry, while β-catenin expression in tissues was used by immunofluorescence. The expression of FGFR and insulin-like growth factor 1 (IGF-1) in the skin was determined to evaluate using real-time quantitative polymerase chain reaction (RT-qPCR). The levels of DHT and 5α-reductase in the experimental mice were determined by ELISA. Results The GC-MS analysis results showed that the extracts were rich in alkanes and aromatic compounds, specifically benzaldehyde, which was the highest component in the cold vacuum extraction, while pipecolic acid was the main component in the ethanol extract. This indicates that C. serrulata has components that exhibit strong inhibitory ability against the growth of five common bacterial strains, expressing excellent free radical scavenging ability. In addition, the active ingredients in C. serrulata were found to significantly deregulate the protein levels in the skin of androgenetic alopecia (AGA) mice, with the levels of IL-6. They were also able to significantly inhibit VEGF reduction. The β-catenin was being significantly upregulated in skin tissue. In addition, FGFR and IGF-1 gene expression also increased. The 5α-reductase and dihydrotestosterone (DHT) can be reduced in the C. serrulata treatment. Conclusion Our data indicate that C. serrulata extract could be beneficial supplements of natural antioxidative, antibacterial, and anti-alopecia agents.

MiRNA-470-5p suppresses epithelial-mesenchymal transition of embryonic palatal shelf epithelial cells by targeting Fgfr1 during palatogenesis.

MicroRNAs (miRNAs) have been identified as crucial modulators of gene expression and to play a role in palatogenesis. The aim of this study was to explore the potential role and regulatory mechanisms of miRNAs during palatogenesis. RNA-sequencing was performed to compare the RNA expression profiles of mouse embryonic palatal shelf (MEPS) tissue between an all-trans retinoic acid (ATRA)-induced group and control group, followed by reverse transcription-quantitative polymerase chain reaction for validation, demonstrating upregulated expression of miRNA-470-5p and downregulated expression of Fgfr1 in the ATRA-induced group. The specific binding sites of miRNA-470-5p that potentially govern Fgfr1 expression were predicted by miRanda and TargetScan. The relationship between miRNA-470-5p and Fgfr1 was validated in HEK293T cells by luciferase reporter assays, confirming that miR-470-5p acts directly on the Fgfr1 3'-untranslated region. Fgfr1 mRNA and FGFR1 protein levels were markedly downregulated in MEPS epithelial cells over-expressing miRNA-470-5p. Functional experiments in vitro with CCK-8, cell colony formation, and 5-ethynyl-2'-deoxyuridine (EdU) staining assays revealed that upregulated miRNA-470-5p expression could inhibit the epithelial-mesenchymal transition (EMT) of MEPS epithelial cells by targeting Fgfr1. These findings provide a new molecular mechanism of cleft palate formation, which can inform the development of new treatment and/or prevention targets.

ASXL3 gene mutations inhibit cell proliferation and promote cell apoptosis in mouse cardiomyocytes by upregulating lncRNA NONMMUT063967.2

Congenital heart disease (CHD) is a serious condition with unknown etiology. In a recent study, a compound heterozygous mutation (c.3526C > T [p.Arg1176Trp] and c.4643A > G [p.Asp1548Gly]) in the ASXL3 gene was identified, which is associated with CHD. This mutation was overexpressed in HL-1 mouse cardiomyocyte cells, leading to increased cell apoptosis and decreased cell proliferation. However, whether this effect is mediated by long noncoding RNAs (lncRNAs) is yet to be determined. We identified the differences among lncRNA and mRNA profiles in mouse heart tissues using sequencing to explore this issue. We detected HL-1 cell proliferation and apoptosis through CCK8 and flow cytometry. Fgfr2, lncRNA, and Ras/ERK signaling pathway expressions were evaluated using quantitative real time polymerase chain reaction (qRT-PCR) and western blot (WB) assays. We also conducted functional investigations by silencing lncRNA NONMMUT063967.2. The sequencing revealed significant changes in lncRNA and mRNA profiles, with the expression of lncRNA NONMMUT063967.2 being significantly promoted in the ASXL3 gene mutations group (MT) while the expression of Fgfr2 being downregulated. The in vitro experiments showed that ASXL3 gene mutations inhibited the proliferation of cardiomyocytes and accelerated cell apoptosis by promoting the expression of lncRNAs (NONMMUT063967.2, NONMMUT063918.2, and NONMMUT063891.2), suppressing the formation of FGFR2 transcripts, and inhibiting the Ras/ERK signaling pathway. The decrease in FGFR2 had the same effect on the Ras/ERK signaling pathway, proliferation, and apoptosis in mouse cardiomyocytes as ASXL3 mutations. Further mechanistic studies revealed that suppression of lncRNA NONMMUT063967.2 and overexpression of FGFR2 reversed the effects of the ASXL3 mutations on the Ras/ERK signaling pathway, proliferation, and apoptosis in mouse cardiomyocytes. Therefore, ASXL3 mutation decreases FGFR2 expression by upregulating lncRNA NONMMUT063967.2, inhibiting cell proliferation and promoting cell apoptosis in mouse cardiomyocytes.

TRLS-08. EXPERIENCE WITH THE SELECTIVE FIBROBLAST GROWTH FACTOR INHIBITOR ERDAFITINIB IN THREE PEDIATRIC PATIENTS WITH CNS TUMORS

Abstract Activation of FGF signaling has been described for at least 3% of pediatric solid tumors including pediatric gliomas. Therapeutic actionability of FGF signaling activations, however, remains challenging. Here, we report on three patients with FGFR activation treated with erdafitinib, originally approved for the treatment of FGFR3 or FGFR2 mutated urothelial carcinoma. Our patients were treated for posterior fossa group A ependymoma (patient (Pat) 1&2) and glioma NOS °II-III (Pat3). Dose of erdafitinib at initiation of therapy was 5,2mg/kg/d; 3,8mg/kg/d and 2,8mg/kg/d for Pat1-3 respectively. Rationale for treatment with erdafitinib was increased FGFR3 expression in tumor tissue (TT) of Pat1, increased FGFR1 expression in TT of Pat2, and in Pat3 an activating FGFR1 internal tandem duplication (ITD). Both ependymoma patients received erdafitinib as a fourth line treatment and progressed rapidly under therapy. Treatment was discontinued after 2 weeks (Pat2) and 3 months (Pat1) due to progressive disease. Pat3, with the FGFR1 ITD, responded very well to therapy with a decrease in tumor size and reduced contrast-enhancement after 3&6 months. Therapy was discontinued after six months due to dystrophic nail changes. During treatment, our patients reported on diarrhea, abdominal pain, pain in the lower extremities, dysgeusia, hypersensitivity of the oral mucosa, dry skin and dystrophic nail changes. Additionally, we observed a distinct increase in longitudinal growth (Pat1&3), increased serum phosphate levels, LFPs, alpha-amylase, cholinesterase, alkaline phosphatase and LDH. Summing up, treatment with erdafitinib has high potential for a selected cohort of pediatric CNS tumor patients, as demonstrated by the treatment response of Pat3 with the FGFR1 IDT. However, further defining the exact molecular alterations that predict the individual patient’s response as well as side effects in the pediatric population are imperative to elucidate the further role of erdafitinib in treatment of pediatric CNS tumors.

Prediction of nonresponse and theranostic imaging in MIBC being resistant to NACT within the Bladder BRIDGister.

e16603 Background: Patients with muscle invasive urothelial carcinoma achieving pathological complete response upon neoadjuvant chemotherapy (NACT) have improved prognosis. Previously we did show that luminal tumors respond better to NACT, while FGFR1 expression is associated with NACT resistance (Ecke et al. 2022). Interestingly the expression of the radioligand targets CXCR4 and FAP is found in chemoresistant, stroma-associated tumors. The objective of this study was to prospectively validate the predictive value of molecular target typing from TUR biopsy samples and compare PET CT imaging by FDG and FAP radioligand imaging in selected patients after two cycles of NACT to justify subsequent adaptive trial concepts within the "Bladder BRIDGister." Methods: Formalin fixed paraffin embedded tissues (FFPE) from transurethral resections (TUR) before chemotherapy and cystectomy samples after NACT of 36 patients were retrospectively collected and 650 TURB samples were prospectively collected as part of the Bladder BRIDGister. RNA from FFPE tissues were extracted by commercial kits, relative gene expression of subtyping markers (KRT5, KRT20, FGFR1) and radioligand target genes (CXCR4, FAP) were analyzed by standardized RT-qPCR systems (STRATIFYER Molecular Pathology GmbH, Cologne). PET CT Imaging by FDG and FAP was performed after two cycles cisplatinum based NACT. Results: The neoadjuvant cohort consisted of 36 patients (median age 69, male 83%, female 17%) with 92% of patients being node negative. Hierarchical clustering revealed CXCR4 and FAP to be elevated in stromal rich, KRT5 & KRT20 negative tumors not responding to NACT. Elevated FAP mRNA expression was sig. associated with resistance to NACT (chi2 4.314 p=0,0378). Combining elevated FAP and CXCR4 mRNA expression did identify 1/3 of the patients to be at high risk of NACT resistance (90%). Exemplarily one pT3 G3 patient was selected for PET CT imaging after two cycles that was predicted to be unresponsive to NACT by molecular subtyping. FDG PET CT revealed a hepatic metastatic lesion. In contrast FAP PET CT indicated multiple hepatic and a pancreatic metastatic lesion indicating tumor progression under NACT. Therapy was switched to MVAC with persistent non response. Then pembrolizumab monotherapy was administered due to PD-L1 positivity of the initial TURB (10% TPS /CPC 15). However there still was fulminant progression of the liver metastasis so that ICI therapy had to be stopped. Conclusions: Expression of the radioligand targets CXCR4 and FAP has been shown to be associated with aggressive stromal associated tumors and being resistant to NACT. This could be validated by selecting patients after two cycles of NACT for PET/CT imaging. Stratified FAP PET/CT turned out to be more sensitive than conventional FDG PET CT and may enable future theranostic treatment combinations in patients unresponsive to standard chemo- or immunotherapies.

Sitagliptin therapy improves myocardial perfusion and arteriolar collateralization in chronically ischemic myocardium: A pilot study.

Dipeptidyl peptidase 4 inhibitors (DPP4i) may be cardioprotective based on several small animal and clinical studies, though randomized control trials have demonstrated limited benefit. Given these discrepant findings, the role of these agents in chronic myocardial disease, particularly in the absence of diabetes, is still poorly understood. The purpose of this study was to determine the effects of sitagliptin, a DPP4i, on myocardial perfusion and microvessel density in a clinically relevant large animal model of chronic myocardial ischemia. Normoglycemic Yorkshire swine underwent ameroid constrictor placement to the left circumflex artery to induce chronic myocardial ischemia. Two weeks later, pigs received either no drug (CON, n = 8) or 100 mg oral sitagliptin (SIT) daily (n = 5). Treatment continued for 5 weeks, followed by hemodynamic measurements, euthanasia, and tissue harvest of ischemic myocardium. There were no significant differences in myocardial function between CON and SIT as measured by stroke work (p > 0.5), cardiac output (p = 0.22), and end-systolic elastance (p = 0.17). SIT was associated with increased absolute blood flow at rest (17% increase, IQR 12-62, p = 0.045) and during pacing (89% increase, IQR 83-105, p = 0.002). SIT was also associated with improved arteriolar density (p = 0.045) compared with CON, without changes in capillary density (p = 0.72). SIT was associated with increased expression of pro-arteriogenic markers MCP-1 (p = 0.003), TGFß (p = 0.03), FGFR1 (p = 0.002), and ICAM-1 (p = 0.03), with a trend toward an increase in the ratio of phosphorylated/active PLCγ1 to total PLCγ1 (p = 0.11) compared with CON. In conclusion, in chronically ischemic myocardium, sitagliptin improves myocardial perfusion and arteriolar collateralization via the activation of pro-arteriogenic signaling pathways.

The circRNA-0001361/miR-491/FGFR4 axis is associated with axillary response evaluated by ultrasound following NAC in subjects with breast cancer

BackgroundmiR-491-5p has been reported to regulate the expression of FGFR4 and promote gastric cancer metastasis. Hsa_circ_0001361 was demonstrated to play an oncogenic role in bladder cancer invasion and metastasis by sponging the expression of miR-491-5p. This work aimed to study the molecular mechanism of the effect of hsa_circ_0001361 on axillary response in the treatment of breast cancer. MethodsUltrasound examinations was performed to evaluate the response of breast cancer patients receiving NAC treatment. Quantitative real-time PCR, IHC assay, luciferase assay and Western blot were performed to analyze the molecular interaction between miR-491, circRNA_0001631 and FGFR4. ResultsPatients with low circRNA_0001631 expression had a better outcome after NAC treatment. The expression of miR-491 was remarkably higher in the tissue sample and serum collected from patients with lower circRNA_0001631 expression. On the contrary, the FGFR4 expression was notably suppressed in the tissue sample and serum collected from patients with lower circRNA_0001631 expression when compared with patients with high circRNA_0001631 expression. The luciferase activities of circRNA_0001631 and FGFR4 were effectively suppressed by miR-491 in MCF-7 and MDA-MB-231 cells. Moreover, inhibition of circRNA_0001631 expression using circRNA_0001361 shRNA effectively suppressed the expression of FGFR4 protein in MCF-7 and MDA-MB-231 cells. Up-regulation of circRNA_0001631 expression remarkably enhanced the expression of FGFR4 protein in MCF-7 and MDA-MB-231 cells. ConclusionOur study suggested that the up-regulation of hsa_circRNA-0001361 could up-regulate the expression of FGFR4 via sponging the expression of miR-491-5p, resulting in the alleviated axillary response after neoadjuvant chemotherapy (NAC) in breast cancer.

FGFR2 modulates the Akt/Nrf2/ARE signaling pathway to improve angiotensin II-induced hypertension-related endothelial dysfunction

ABSTRACT Background Fibroblast growth factor receptor (FGFR)2 expression was decreased in hypertension patients while its role in hypertension was not explored. This experiment aimed to investigate the expression ofFGFR2 in angiotensin II (Ang II)-induced human umbilical vein endothelial cells (HUVECs) and the role of FGFR2 in improving AngII-induced hypertension-related endothelial dysfunction. Methods AngII-induced HUVECs simulated the hypertension model in vitro. The expression of FGFR2 in Ang II-induced HUVECs and transfected HUVECswas detected by RT-qPCR and western blot. The viability, apoptosis, migration and tube formation ability of Ang II-induced HUVECs were analyzed by Methyl Thiazolyl Tetrazolium (MTT) assay, flow cytometry analysis, wound healing assay and tube formation assay.Detectionof lactate dehydrogenase (LDH), caspase 3, Nitric Oxide (NO) and oxidative stress levels was conducted by assay kits and reactive oxygen species (ROS) level was detected by DCFH-DA assay. The expression of apoptosis-related proteins, protein kinase B(Akt)/nuclear factor E2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway-related proteins, phospho(p)-endothelial nitric oxide synthase (eNOS) and eNOS was determined by western blot. Results The expression of FGFR2 was decreased in Ang II-induced HUVECs. FGFR2overexpression increased viability, suppressed apoptosis and oxidative stress, and improve endothelial dysfunction of AngII-induced HUVECs through activating the Akt/Nrf2/ARE signaling pathway. MK-2206 (Akt inhibitor) could weaken the effect of FGFR2overexpression to reduce viability, promote apoptosis and oxidative stress, and aggravate endothelial dysfunction of Ang II-inducedHUVECs. Conclusion Inconclusion, FGFR2activated the Akt/Nrf2/ARE signaling pathway to improve AngII-induced hypertension-related endothelial dysfunction.

The IBD-candidate gene, PTPN2, Regulates Goblet Cell Number and Expression of Intestinal Epithelial Cell Markers in a Regional-specific Manner in Mice

Loss-of-function variants in the Protein Tyrosine Phosphatase non-receptor Type 2 ( PTPN2) gene are associated with increased risk of Inflammatory Bowel Disease (IBD). PTPN2 encodes T Cell Protein Tyrosine Phosphatase (TCPTP), a negative regulator of intracellular signaling pathways including JAK-STAT. PTPN2 is critical for intestinal epithelial cell (IEC) barrier maintenance, IEC-macrophage crosstalk, and modulating the gut microbiota in mice and IBD patients. Aim: To determine if Ptpn2 loss compromises IEC subtypes that restrict gut dysbiosis. Methods: Ileal and colonic IEC subtypes and their function were assessed by PAS staining of goblet cells and immunostaining. RNA isolated from colonic IECs of whole-body Ptpn2-wild-type (WT), heterozygous (Het) and KO mice was assayed by two separate Nanostring ® panels: PanCancer and AutoImmune totaling >1500 targets. Flow cytometry was performed to evaluate abundance of mucosal-associated immune cells. Results: Goblet cells were reduced in the ileal and cecal crypts compared with WT mice (p<0.05; n=5) while numbers in the proximal and distal colon were variable. Ki-67 immunostaining revealed increased proliferating cells in the proximal and distal colon (p<0.01; n=3). Nanostring analysis had 1399 targets with detectable expression. Notably, expression of growth factors Egf and Fgfr3, differentiation factors Atoh1 and Mycn, tuft cell marker Dclk1, and intestinal stem cell marker Lgr5, were all downregulated in colonic IECs from Ptpn2-KO mice compared with WT (p<0.05; FDR<0.1; n=4). Moreover, abundance of mucosal neutrophils, macrophages, CD4 + expressing IFN-γ, CD8 + expressing TNF/IFN-γ, and CD4 + expressing IL-22 T-cells were higher in colon and cecum of Ptpn2-KO mice compared with WT and HET mice (p<0.01; n=5), whereas abundance of IL-4 expressing CD4 + cells, and Tregs expressing IL-10 were decreased in all intestinal segments of Ptpn2-KO mice (p<0.01; n=5). Conclusion: Ptpn2 loss negatively impacts abundance of IEC subtypes in a region-specific manner, affecting epithelial proliferation and expression of critical differentiation/cell markers. The elevated abundance of immune cells expressing pro-inflammatory signals accompanied by decreased levels of cells expressing IL-4 and IL-10, could contribute to a skewed abundance of IEC subtypes and their function. The observed effects may contribute to the increased susceptibility to infection and the dysbiotic microbiota in Ptpn2-deficient mice, and partly explain association of PTPN2 variants with dysbiosis in clinical IBD. Supported by NIH 2R01DK091281, 1R01AI153314-01, R21AI152017 and R01AI165490 (DFM). This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

18F-labeled FGFR1 peptide: a new PET probe for subtype FGFR1 receptor imaging.

The fibroblast growth factor receptor (FGFR) family is highly expressed in a variety of tumor types and represents a new target for cancer therapy. Different FGFR subtype aberrations have been found to exhibit highly variable sensitivity and efficacy to FGFR inhibitors. The present study is the first to suggest an imaging method for assessing FGFR1 expression. The FGFR1-targeting peptide NOTA-PEG2-KAEWKSLGEEAWHSK was synthesized by manual solid-phase peptide synthesis and high-pressure liquid chromatography (HPLC) purification and then labeled with fluorine-18 using NOTA as a chelator. In vitro and in vivo experiments were conducted to evaluate the stability, affinity and specificity of the probe. Tumor targeting efficacy and biodistribution were evaluated by micro-PET/CT imaging in RT-112, A549, SNU-16 and Calu-3 xenografts. The radiochemical purity of [18F]F-FGFR1 was 98.66% ± 0.30% (n = 3) with excellent stability. The cellular uptake rate of [18F]F-FGFR1 in the RT-112 cell line (FGFR1 overexpression) was higher than that in the other cell lines and could be blocked by the presence of excess unlabeled FGFR1 peptide. Micro-PET/CT imaging revealed a significant concentration of [18F]F-FGFR1 in RT-112 xenografts with no or very low uptake in nontargeted organs and tissues, which demonstrated that [18F]F-FGFR1 was selectively taken up by FGFR1-positive tumors. [18F]F-FGFR1 showed high stability, affinity, specificity and good imaging capacity for FGFR1-overexpressing tumors in vivo, which provides new application potential in the visualization of FGFR1 expression in solid tumors.

Fibroblast growth factor receptors 1 and 4 combined with lymph node metastasis predicts poor prognosis in oral cancer.

The fibroblast growth factor receptor (FGFR) members including FGFR1-4 have been identified as promising novel therapeutic targets and prognostic markers in multiple solid tumors. However, the predictive role of the expression of FGFR proteins in oral squamous cell carcinoma (OSCC) requires further exploration. Immunohistochemical evaluation of FGFR1-4 was performed on 161 paired OSCC samples. The associations of FGFRs with clinicopathologic and prognostic parameters were analyzed. To further assess the contribution of FGFRs to OSCC proliferation, cell lines, and one PDX model was utilized to examine the anti-tumor effect of the pan-FGFR inhibitor AZD4547. All FGFR members were found to be overexpressed in OSCC tumors when compared to normal tissues, and their expression was significantly associated with poor overall survival and disease-free survival. Multivariate Cox regression analysis revealed high expression of FGFR1 (p = 0.014) and FGFR4 (p = 0.009) were independent prognostic factors and co-overexpression of FGFR1 and FGFR4 with lymph node metastasis increased HR for death (p = 0.02). The pan-FGFR inhibitor AZD4547 showed anti-tumor activity in cell lines and in a patient-derived xenograft of OSCC. This study highlights the co-overexpression of FGFR1 and FGFR4 as a significantly poor prognosis indicator in OSCC when combined with lymph node metastasis.

FGFR4 and EZH2 inhibitors synergistically induce hepatocellular carcinoma apoptosis via repressing YAP signaling

BackgroundHepatocellular carcinoma (HCC) is one of the most common and lethal cancers worldwide, but current treatment options remain limited and cause serious life-threatening side effects. Aberrant FGFR4 signaling has been validated as an oncogenic driver of HCC, and EZH2, the catalytic subunit of the PRC2 complex, is a potential factor that contributes to acquired drug resistance in many tumors, including HCC. However, the functional relationship between these two carcinogenic factors, especially their significance for HCC treatment, remains unclear. In this study, we systematically evaluated the feasibility of a combination therapy targeting FGFR4 and EZH2 for HCC.MethodsRNA sequencing data of patients with Liver hepatocellular carcinoma (LIHC) from The Cancer Genome Atlas (TCGA) were analyzed to determine FGFR4 and EZH2 expression and their interaction with prognosis. Moreover, the HCC cell lines, zebrafish/mouse HCC xenografts and zebrafish HCC primary tumors were treated with FGFR4 inhibitor (Roblitinib) and/or EZH2 inhibitor (CPI-169) and then subjected to cell proliferation, viability, apoptosis, and tumor growth analyses to evaluate the feasibility of combination therapy for HCC both in vitro and in vivo. Furthermore, RNA-Seq was performed in combination with ChIP-Seq data analysis to investigate the critical mechanism underlying the combination treatment with Roblitinib and CPI-169.ResultsEZH2 accumulated through the non-canonical NF-kB signaling in response to FGFR4 inhibitor treatment, and the elevated EZH2 levels led to the antagonism of HCC against Roblitinib (FGFR4 inhibitor). Notably, knockdown of EZH2 sensitized HCC cells to Roblitinib, while the combination treatment of Roblitinib and CPI-169 (EZH2 inhibitor) synergistically induced the HCC cell apoptosis in vitro and suppressed the zebrafish/mouse HCC xenografts and zebrafish HCC primary tumors development in vivo. Moreover, Roblitinib and CPI-169 synergistically inhibited HCC development via repressing YAP signaling.ConclusionsCollectively, our study highlighted the potential of the therapeutic combination of FGFR4 and EZH2 inhibitors, which would provide new references for the further development of clinical treatment strategies for HCC.