Secreted Frizzled-related Protein 4 Research Articles

JMJD2A mediates transcriptional activation of SFRP4 and regulates oxidative stress and mitochondrial dysfunction in heart failure.

The importance of mitochondrial dysfunction and oxidative stress has been indicated in the progression of heart failure (HF). The molecular mechanisms, however, remain to be fully elucidated. This study aimed to explore the role and underlying mechanism of secreted frizzled-related protein 4 (SFRP4) in these two events in HF. Mice with HF were developed using transverse aortic constriction, and hematoxylin-eosin staining, MASSON staining, and Terminal deoxynucleotidyl transferase (TdT)-mediated 2'-Deoxyuridine 5'- Triphosphate nick end labeling (TUNEL assays) were conducted to detect morphological damage in the myocardial tissues of mice. HL-1 mouse cardiomyocytes were induced with isoproterenol (ISO), and cell viability and apoptosis were examined using cell counting kit-8 and TUNEL assays. SFRP4 and Jumonji domain-containing protein 2A (JMJD2A) were highly expressed in myocardial tissues. Suppression of SFRP4 alleviated apoptosis and fibrosis in myocardial tissues of mice. In addition, the extent of mitochondrial dysfunction and oxidative stress in damaged myocardial tissues and HL-1 cells was mitigated by SFRP4 inhibition as well. JMJD2A catalyzed demethylation modification of the SFRP4 promoter, thus promoting SFRP4 transcription in the development of HF. JMJD2A is responsible for SFRP4 transcription activation in the failing hearts of mice. Blockade of JMJD2A or SFRP4 might be a novel therapy effective in mitigating HF progression.

Proteomic detection of COX-2 pathway-related factors in patients with adenomyosis.

Investigating the relationship between cyclooxygenase-2 (COX-2) pathway-related factors and clinical features in patients with adenomyosis by proteomics could provide potential therapeutic targets. This study recruited 40 patients undergoing surgical hysterectomy and pathological diagnosis of adenomyosis, collected ectopic endometrial specimens, and recorded clinical data. The expression levels of COX-2 in ectopic uterus lesions were detected using the immunohistochemical (IHC) SP method. The 40 samples were then divided into a COX-2 low or high expression group. Five samples with the most typical expression levels were selected from each of the two groups and the differential proteins between the two groups were identified using label-free quantitative proteomics. WW domain-binding protein 2 (WBP2), interferon induced transmembrane protein 3 (IFITM3), and secreted frizzled-related protein 4 (SFRP4) were selected for further verification, and their relationships with COX-2 and clinical characteristics were analyzed. There were statistically significant differences in the expression of WBP2, IFITM3, and SFRP4 between the COX-2 low and high expression groups (P < 0.01). The expressions of COX-2, IFITM3, and SFRP4 were significantly correlated with dysmenorrhea between the two groups (P < 0.05), but not with uterine size or menstrual volume (P > 0.05). However, there was no significant correlation between the expression of WBP2 and dysmenorrhea, uterine size, and menstruation volume in both the high expression and low expression groups (P > 0.05). COX-2, IFITM3, SFRP4, and WBP2 may be involved in the pathogenesis of adenomyosis. COX-2, IFITM3, and SFRP4 may serve as potential molecular biomarkers or therapeutic targets in dysmenorrhea in patients with early adenomyosis.

Characterization of Wnt signaling pathway under treatment of Lactobacillus acidophilus postbiotic in colorectal cancer using an integrated in silico and in vitro analysis

Colorectal cancer (CRC) is a prevalent and life-threatening cancer closely associated with the gut microbiota. Probiotics, as a vital microbiota group, interact with the host’s colonic epithelia and immune cells by releasing a diverse range of metabolites named postbiotics. The present study examined the effects of postbiotics on CRC’s prominent differentially expressed genes (DEGs) using in silico and in vitro analysis. Through single-cell RNA sequencing (scRNA-seq), we identified four DEGs in CRC, including secreted frizzled-related protein 1 (SFRP1), secreted frizzled-related protein 2 (SFRP2), secreted frizzled-related protein 4 (SFRP4), and matrix metallopeptidase 7 (MMP7). Enrichment analysis and ExpiMap, a novel deep learning-based method, determined that these DEGs are involved in the Wnt signaling pathway as a primary cascade in CRC. Also, spatial transcriptome analysis showed specific expression patterns of the SFRP2 gene in fibroblast cell type. The expression of selected DEGs was confirmed on CRC and normal adjacent tissues using Real-Time quantitative PCR (RT-qPCR). Moreover, we examined the effects of postbiotics extracted from Lactobacillus acidophilus (L. acidophilus) on the proliferation, migration, and cell cycle distribution of HT-29 cells using MTT, scratch, and flow cytometry assays. Our results showed that L. acidophilus postbiotics induce cell cycle arrest at G1 phase and also had anti-proliferative and anti-migration effects on HT-29 cells, while it did not exert anti-proliferative activity on control fibroblasts. Finally, we revealed that treating HT-29 cells with postbiotics can affect the expression of selected DEGs. We suggested that L. acidophilus postbiotics have therapeutic potential in CRC by modulating key genes in the Wnt pathway.

In Silico identification of novel phytochemicals that target SFRP4: An early biomarker of diabesity.

The simultaneous coexistence of complicated metabolic conditions like obesity and diabetes within an individual is known as diabesity. Obesity is the key factor for many chronic diseases, including insulin resistance and type 2 diabetes (T2D). Metabolic stress due to nutrient overload releases different inflammatory mediators. Secreted frizzled-related protein 4 (SFRP4) is also an inflammatory mediator that impairs insulin secretion. SFRP4 acts as an early biomarker for diabesity expressed with interleukin-1 beta (IL-1β) in the adipose tissues that hinder the exocytosis of insulin-secreting granules from the pancreatic β-cells and is a potential target for preserving β-cell dysfunction and the diabesity treatment. The current study aimed to screen potential bioactive compounds targeting and inhibiting the diabesity-linked SFRP4 protein through an in silico approach. The three-dimensional (3D) structure of human SFRP4 was predicted through comparative modeling techniques and evaluated by various online bioinformatics tools. The molecular docking and MD simulation investigations were carried out against phytochemicals with anti-diabetic and anti-obesity properties to shortlist the best SFRP4 inhibitor. Hesperetin, Curcumin, Isorhamnetin, Embelin, Epicatechin, and Methyl Eugenol interacted strongly with SFRP4 by displaying zero RMSD and binding affinities of -6.5, -6.4, -6.3, -5.3, -6.3 and -5.8 kcal/mol respectively. Additionally, the root mean square fluctuation and root mean square deviation graphs from the MD simulation results demonstrated that hesperetin has good variations throughout the simulation period as compared to others. This dynamic stability and control behavior of hesperetin, when it interacts with SFRP4, shows that it has the potential to modulate the function and activity of the protein. Therefore, hesperetin is identified as an effective and top drug candidate through this analysis for preserving beta-cell function and treating diabesity by targeting SFRP4. The findings of this study could be useful in the design and development of diabesity drugs.

Early diagnosis of non-alcoholic fatty liver disease: the role of biomarkers and complex indices of non-alcoholic fatty liver steatosis

Metabolic syndrome is a series of pathologies united by a similar pathogenesis, the end of which, most often, is cardiovascular accidents, which are leaders among the causes of death in the population around the world. Non-alcoholic fatty liver disease (NAFLD) is the hepatic equivalent of the metabolic syndrome, registered earlier than all other equivalents, on the rights of the liver as a first-line energy depot. At the same time, according to multicenter studies, 95% of people with NAFLD (any stage) are not diagnosed with the disease. Clarification of additional risk factors for NAFLD and the presence of a specific biomarker of non-alcoholic liver steatosis would make it possible to stop the vicious cascade of metabolic processes, which in the future can lead to a significant increase in the life expectancy of the population. The potentially high role of Secreted Frizzled Related Protein-4 (SFRP4) adipokine in the early diagnosis of NAFLD is known. The aim of the study was to optimize the early diagnosis of non-alcoholic fatty liver disease using modern indices and biomarkers. Materials and methods. The work was carried out at the Department of Faculty and Hospital Therapy of the Chuvash State University named after I. N. Ulyanov” in the period from 2016 to 2020. This study included several stages: first of all, a retrospective analysis of 1150 outpatient records of patients from several medical organizations of the Chuvash Republic for the period 2016-2018 was carried out. to form two study groups: experimental and control. At the second stage, as a result of applying the exclusion criteria, 162 people remained in the experiment: 110 from the experimental group, 52 from the control group. The subjects of both groups were compared by gender and age, the age range of the subjects varied from 18 to 80 years old with an average value of 48.3 years. Further, the patients undergo a detailed examination, according to the presented plan: Collection of complaints, medical history, objective examination. Laboratory studies (general and biochemical blood tests, lipidogram, assessment of the level of serum adipokine SFRP4). Instrumental studies (ultrasound of the OBP, TE (SAR), ESP with elastometry). Evaluation of the most informative complex indices for the early diagnosis of NAFLD: MI, IVO indices, HSI, FLD-I. Further, all the necessary statistical processing and analysis of the obtained data were performed (Microsoft Office Excel 2016, StatTech v. 2.8.8 (developer - Stattech LLC, Russia)). Results. Accessible (not requiring the use of additional time and material costs) NAFLD indices with the highest sensitivity rates (99.1% and 98.2%, respectively) were MI and IVO. A noticeable direct correlation was traced between MI (p=0.640), moderate - between the IVO (p=0.398) and the elastographically determined index of non-alcoholic liver steatosis. High sensitivity and specificity of skin manifestations (xanthoma, xanthelasma - 69.6% and 89.7% and seborrheic dermatitis - 82.0% and 71.4%) were found in relation to early manifestations of NAFLD. From anthropometric indicators: the CW/CF index has a pronounced (ρ=0.643), CW - moderate (ρ=0.238), and BMI - a weak direct (ρ=0.223) correlation with the elastographically determined index of non-alcoholic liver steatosis. Adipokine SFRP4 correlates (ρ=0.841) with early manifestations of hepatic steatosis in patients, as determined by TE in CAP mode.

Ghrelin promotes cardiomyocyte differentiation of adipose tissue‑derived mesenchymal stem cells by DDX17‑mediated regulation of the SFRP4/Wnt/β‑catenin axis.

Adipose tissue‑derived mesenchymal stem cells (ADMSCs) differentiate into cardiomyocytes and may be an ideal cell source for myocardial regenerative medicine. Ghrelin is a gastric‑secreted peptide hormone involved in the multilineage differentiation of MSCs. To the best of our knowledge, however, the role and potential downstream regulatory mechanism of ghrelin in cardiomyocyte differentiation of ADMSCs is still unknown. The mRNA and protein levels were measured by reverse transcription‑quantitative PCR and western blotting. Immunofluorescence staining was used to show the expression and cellular localization of cardiomyocyte markers and β‑catenin. RNA sequencing was used to explore the differentially expressed genes (DEGs) that regulated by ghrelin. The present study found that ghrelin promoted cardiomyocyte differentiation of ADMSCs in a concentration‑dependent manner, as shown by increased levels of cardiomyocyte markers GATA binding protein 4, α‑myosin heavy chain (α‑MHC), ISL LIM homeobox 1, NK2 homeobox 5 and troponin T2, cardiac type. Ghrelin increased β‑catenin accumulation in nucleus and decreased the protein expression of secreted frizzled‑related protein 4 (SFRP4), an inhibitor of Wnt signaling. RNA sequencing was used to determine the DEGs regulated by ghrelin. Functional enrichment showed that DEGs were more enriched in cardiomyocyte differentiation‑associated terms and Wnt pathways. Dead‑box helicase 17 (DDX17), an upregulated DEG, showed enhanced mRNA and protein expression levels following ghrelin addition. Overexpression of DDX17 promoted protein expression of cardiac‑specific markers and β‑catenin and enhanced the fluorescence intensity of α‑MHC and β‑catenin. DDX17 upregulation inhibited protein expression of SFRP4. Rescue assay confirmed that the addition of SFRP4 partially reversed ghrelin‑enhanced protein levels of cardiac‑specific markers and the fluorescence intensity of α‑MHC. In conclusion, ghrelin promoted cardiomyocyte differentiation of ADMSCs by DDX17‑mediated regulation of the SFRP4/Wnt/β‑catenin axis.

Identifying immune cell infiltration and diagnostic biomarkers in heart failure and osteoarthritis by bioinformatics analysis.

Heart failure (HF) and osteoarthritis (OA) are medical conditions that can significantly impact daily activities. Evidence has shown that HF and OA may share some pathogenic mechanisms. However, the underlying genomic mechanisms remain unclear. This study aimed to explore the underlying molecular mechanism and identify diagnostic biomarkers for HF and OA. With the cutoff criteria of fold change (FC) > 1.3 and P < .05, 920, 1500, 2195, and 2164 differentially expressed genes (DEGs) were identified in GSE57338, GSE116250, GSE114007, and GSE169077, respectively. After making the intersection of DEGs, we obtained 90 upregulated DEGs and 51 downregulated DEGs in HF datasets and 115 upregulated DEGs and 75 downregulated DEGs in OA datasets. Afterward, we conducted genome ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, protein-protein interaction (PPI) networks, and hub genes screening based on DEGs. Then, 4 common DEGs (fibroblast activation protein alpha [FAP], secreted frizzled-related protein 4 (SFRP4), Thy-1 cell surface antigen (THY1), matrix remodeling associated 5 [MXRA5]) between HF and OA were screened and validated in GSE5406 and GSE113825 datasets, based on which we established the support vector machine (SVM) models. The combined area under the receiver operating characteristic curve (AUC) of THY1, FAP, SFRP4, and MXRA5 in the HF training and test sets reached 0.949 and 0.928. While in the OA training set and test set, the combined AUC of THY1, FAP, SFRP4, and MXRA5 reached 1 and 1, respectively. The analysis of immune cells in HF revealed high levels of dendritic cell (DC), B cells, natural killer T cell (NKT), Type 1 regulatory T cell (Tr1), cytotoxic T cell (Tc), exhausted T cell (Tex), and mucosal-associated invariant T cell (MAIT), while displaying lower levels of monocytes, macrophages, NK, CD4 + T, gamma delta T (γδ T), T helper type 1 (Th1), T helper type 2 (Th2), and effector memory T cell (Tem). Moreover, the 4 common DEGs were positively correlated with DCs and B cells and negatively correlated with γδ T. In OA patients, the abundance of monocyte, macrophage, CD4 + naïve, and natural T regulatory cell (nTreg) was higher, while the infiltration of CD8 + T, γδ T, CD8 + naïve, and MAIT was lower. The expression of THY1 and FAP was significantly correlated with macrophage, CD8 + T, nTreg, and CD8 + naïve. SFRP4 was correlated with monocyte, CD8 + T, γδ T, CD4 + naïve, nTreg, CD8 + naïve and MAIT. MXRA5 was correlated with macrophage, CD8 + T, nTreg and CD8 + naïve. FAP, THY1, MXRA5, and SFRP4 may be diagnostic biomarkers for both HF and OA, and their correlation with immune cell infiltrations suggests shared immune pathogenesis.

A Study to Evaluate the Role of Secreted Frizzled-Related Protein 4 (SFRP4) as a Potential Novel Biomarker of Type 2 Diabetes Mellitus

ABSTRACT Background: A new inflammation mediator called secreted frizzled-related protein 4 (SFRP4), was recently found, the secretion of which is regulated by interleukin-1β. SFRP4 as a potential biomarker of early β-cell dysfunction can help to identify high-risk individuals who are going to develop diabetes in the future. It is highly expressed in β-cells of islets and its levels increase several years before diabetes diagnosis. Objectives: This study was conducted with an objective to estimate and correlate SFRP4 in pre-diabetes, type 2 diabetes, and non-diabetes persons, and evaluate the predictive risk assessment of SFRP4 as a novel biomarker. Materials and Methods: In this cross-sectional observational study, a total of 300 human participants were included among which 100 were prediabetic, 100 were diabetic, and 100 were age- and gender-matched control individuals from a community, all of whom were selected through a predesigned screening questionnaire and inclusion and exclusion criteria from January 2020 to January 2022 in Banke district, Nepal. Serum SFRP4 and IL-1β levels were determined by ELISA. Results: There was a statistically significant difference in body mass index (BMI), waist circumference (WC), systolic blood pressure (SBP), fasting insulin, fasting plasma glucose (FPG), two-hour post-load plasma glucose (2hPG), glycosylated hemoglobin (HbA1c), insulin resistance (HOMA-IR), Homeostasis model assessment of β cell function (HOMA-β%), high-sensitivity C-reactive protein (hs-CRP), total cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL) between the three groups, with a progressive increase from the normal glucose tolerance (NGT) to impaired glucose tolerance (IGT) groups and with the highest value in the type 2 diabetes mellitus (T2DM) groups (P &lt; 0.05). However, diastolic blood pressure (DBP) and IL-1β showed a significant difference between the NGT and T2DM groups (P &lt; 0.001) and the NGT and IGT groups (P &lt; 0.001). The median serum SFRP4 concentrations showed a significant difference among three groups (all P &lt; 0.05) and were positively correlated with FPG, HbA1c, hs-CRP, and IL-1 β (P &lt; 0.05). Conclusion: Our study presumes importance as we report increased SFRP4 levels in Asian Nepalis even at the stage of IGT. These findings propose that the increased serum SFRP4 may be a good biomarker of decline in β-cell function and insulin resistance.

Heart failure-related genes associated with oxidative stress and the immune landscape in lung cancer.

Lung cancer is a common comorbidity of heart failure (HF). The early identification of the risk factors for lung cancer in patients with HF is crucial to early diagnosis and prognosis. Furthermore, oxidative stress and immune responses are the two critical biological processes shared by HF and lung cancer. Therefore, our study aimed to select the core genes in HF and then investigate the potential mechanisms underlying HF and lung cancer, including oxidative stress and immune responses through the selected genes. Differentially expressed genes (DEGs) were analyzed for HF using datasets extracted from the Gene Expression Omnibus database. Functional enrichment analysis was subsequently performed. Next, weighted gene co-expression network analysis was performed to select the core gene modules. Support vector machine models, the random forest method, and the least absolute shrinkage and selection operator (LASSO) algorithm were applied to construct a multigene signature. The diagnostic values of the signature genes were measured using receiver operating characteristic curves. Functional analysis of the signature genes and immune landscape was performed using single-sample gene set enrichment analysis. Finally, the oxidative stress-related genes in these signature genes were identified and validated in vitro in lung cancer cell lines. The DEGs in the GSE57338 dataset were screened, and this dataset was then clustered into six modules using weighted gene co-expression network analysis; MEblue was significantly associated with HF (cor = -0.72, p < 0.001). Signature genes including extracellular matrix protein 2 (ECM2), methyltransferase-like 7B (METTL7B), meiosis-specific nuclear structural 1 (MNS1), and secreted frizzled-related protein 4 (SFRP4) were selected using support vector machine models, the LASSO algorithm, and the random forest method. The respective areas under the curve of the receiver operating characteristic curves of ECM2, METTL7B, MNS1, and SFRP4 were 0.939, 0.854, 0.941, and 0.926, respectively. Single-sample gene set enrichment analysis revealed significant differences in the immune landscape of the patients with HF and healthy subjects. Functional analysis also suggested that these signature genes may be involved in oxidative stress. In particular, METTL7B was highly expressed in lung cancer cell lines. Meanwhile, the correlation between METTL7B and oxidative stress was further verified using flow cytometry. We identified that ECM2, METTL7B, MNS1, and SFRP4 exhibit remarkable diagnostic performance in patients with HF. Of note, METTL7B may be involved in the co-occurrence of HF and lung cancer by affecting the oxidative stress immune responses.

SFRP4 Reduces Atherosclerosis Plaque Formation in ApoE Deficient Mice.

Secreted frizzled related protein 4 (SFRP4), a member of the SFRPs family, contributes to a significant function in metabolic and cardiovascular diseases. However, there is not enough evidence to prove the antiatherosclerosis effect of SFRP4 in ApoE knock-out (KO) mice. ApoE KO mice were fed a western diet and injected adenovirus (Ad)-SFRP4 through the tail vein for 12 weeks. Contrasted with the control cohort, the area of atherosclerotic plaque in ApoE KO mice overexpressing SFRP4 was reduced significantly. Plasma high-density lipoprotein cholesterol was elevated in the Ad-SFRP4 group. RNA sequence analysis indicated that there were 96 differentially expressed genes enriched in 10 signaling pathways in the mRNA profile of aortic atherosclerosis lesions. The analysis data also revealed the expression of a number of genes linked to metabolism, organism system, and human disease. In summary, our data demonstrates that SFRP4 could play an important role in improving atherosclerotic plaque formation in the aorta.

Association of Secreted Frizzled-Related Protein 4 with Obesity and Type II Diabetes

Secreted frizzled-related protein 4 (SFRP4) is secreted protein family member similar to the sequence of frizzled receptors of wingless-related integration site (Wnt) signaling pathways which regulate various functions from fetal growth to adulthood. SFRPs are recognized as opponents of Wnt signaling and are thought to be affiliated with Wnts. Further research revealed their interaction with frizzled receptors and functional differences were transferred to these proteins, the power of Wnt signaling without flexibility. Also, SFRP4 is linked to many diseases including obesity, type 2 diabetes (T2D), and cancer. In addition, SFRP4 acts as a biomarker for the diagnosis of T2D and its expression is observed before the clinical diagnosis of T2D. This review is mainly focused on the role of SFRP4 in obesity and its role in β-cell failure that leads to T2D. SFRP4 acts on adipose tissue that causes increased production of adipokines which creates oxidative stress in the pancreas with low levels of antioxidant enzymes in pancreatic β-cells resulting in failure of insulin exocytosis. Inflammation caused by obesity is an important factor in the pathogenesis of insulin resistance and metabolic syndrome. Pro-inflammatory cytokines may induce insulin resistance in adipose tissue, bone tissue and liver by blocking the transmission of insulin signals. SFRP4 secretion is caused by interleukin 1-β (IL1-β).This review also highlights the molecular mechanisms by which SFRP4 leads to T2D. Understanding the cellular pathway and identifying SFRP4 may help to eliminate or reduce the chances of developing T2D.

MiR-23b-3p regulates human endometrial epithelial cell adhesion implying a role in implantation.

miR-23b-3p expression is increased in fertile endometrium during receptivity. This study investigates the function of miR-23b-3p on endometrial adhesion and its downstream targets. The human endometrium undergoes dramatic remodeling throughout the menstrual cycle that is essential for successful blastocyst attachment and implantation in the mid-secretory (receptive) phase. microRNA (miR) plays a role in the preparation of endometrial receptivity. miR-23b-3p expression is increased in fertile endometrium during receptivity. Here, we aimed to investigate miR-23b-3p function during receptivity. qPCR and in situ hybridization were used to investigate the expression and localization of miR-23b-3p in human endometrium, respectively. Ishikawa cells (endometrial epithelial cell line) and endometrial organoid-derived epithelial cells were transfected with miR-23b-3p mimic, and trophoblast progenitor spheroid (blastocyst surrogate) adhesion assay was used to determine effects on blastocyst adhesion to endometrial cells. We demonstrated that miR-23b-3p was significantly upregulated in the fertile endometrium of the receptive phase compared to the non-receptive, proliferative phase. No difference was identified for the expression of miR-23b-3p between fertile and infertile mid-secretory phase endometrium. miR-23b-3p localized to the epithelium and stroma in the mid-secretory phase but was undetectable in the proliferative phase of fertile endometrium. Functionally, miR-23-3p overexpression in Ishikawa cells and fertile endometrial organoid-derived epithelial cells significantly improved their adhesive capacity to trophoblast progenitor spheroids. miR-23b-3p overexpression in infertile endometrial organoid-derived epithelial cells did not improve adhesion. Among 10 miR-predicted gene targets examined, miR-23b-3p overexpression in Ishikawa cells significantly reduced the expression of MET, secreted frizzled-related protein 4 (SFRP4) and acyl-CoA dehydrogenase short/branched chain (ACADSB) compared to control. The reduction of SFRP4 after miR23b-3p overexpression was confirmed by immunoblotting in fertile organoid-derived epithelial cells. SFRP4 expression in fertile endometrium exhibited an inverse expression pattern compared to miR-23b-3p and was higher in the proliferative phase compared to the mid-secretory phase. Overall, miR-23b-3p is likely a critical regulator of endometrial epithelial adhesion and receptivity.

Dupuytren's contracture-associated SNPs increase SFRP4 expression in non-immune cells including fibroblasts to enhance inflammation development.

Dupuytren's contracture (DC) is an inflammatory fibrosis characterized by fibroproliferative disorders of the palmar aponeurosis, for which there is no effective treatment. Although several genome-wide association studies have identified risk alleles associated with DC, the functional linkage between these alleles and the pathogenesis remains elusive. We here focused on two single nucleotide polymorphisms (SNPs) associated with DC, rs16879765 and rs17171229, in secreted frizzled related protein 4 (SFRP4). We investigated the association of SRFP4 with the IL-6 amplifier, which amplifies the production of IL-6, growth factors and chemokines in non-immune cells and aggravates inflammatory diseases via NF-κB enhancement. Knockdown of SFRP4 suppressed activation of the IL-6 amplifier in vitro and in vivo, whereas the overexpression of SFRP4 induced the activation of NF-κB-mediated transcription activity. Mechanistically, SFRP4 induced NF-κB activation by directly binding to molecules of the ubiquitination SFC complex, such as IkBα and βTrCP, followed by IkBα degradation. Furthermore, SFRP4 expression was significantly increased in fibroblasts derived from DC patients bearing the risk alleles. Consistently, fibroblasts with the risk alleles enhanced activation of the IL-6 amplifier. These findings indicate that the IL-6 amplifier is involved in the pathogenesis of DC, particularly in patients harboring the SFRP4 risk alleles. Therefore, SFRP4 is a potential therapeutic target for various inflammatory diseases and disorders, including DC.

Short peptide domains of the Wnt inhibitor sFRP4 target ovarian cancer stem cells by neutralizing the Wnt β-catenin pathway, disrupting the interaction between β-catenin and CD24 and suppressing autophagy

AimsOne of the hallmarks of cancer stem cells (CSC) is hyperactive Wnt β-catenin signaling due to the decreased presence of Wnt antagonists such as secreted frizzled related protein 4 (SFRP4). Cysteine-rich domain (CRD) and netrin-like domain (NLD) are the two functional domains of SFRP4 having anti-tumor properties. In this study, we have explored the effectiveness of short micropeptides SC-301 (from CRD) and SC-401 (from NLD) on CSC properties, EMT, apoptosis and autophagy in ovarian CSCs enriched from PA-1 and SKOV-3 cell lines. Main methodsGene expression analysis, Western blot and immunocytochemistry were performed on ovarian CSCs to evaluate the inhibitory potential of micropeptides to various CSC associated oncogenic properties. Co-immunoprecipitation was performed to detect the binding of CD24 to β-catenin protein complex. CYTO-ID Autophagy Detection Kit 2.0 was used to monitor autophagic flux in peptide treated CSCs. Key findingsIt is clearly seen that the micropeptides derived from both the domains inhibit Wnt pathway, initiate apoptosis, inhibit migration and chemosensitize CSCs. Specifically, CD24, a defining marker of ovarian CSC was suppressed by peptide treatment. Notably, interaction between CD24 and β-catenin was disrupted upon peptide treatment. SFRP4 peptide treatment also suppressed the autophagic process which is crucial for CSC survival. SignificanceThe study demonstrated that although both peptides have inhibitory effects, SC-401 was emphatically more effective in targeting CSC properties and down regulating the Wnt β-catenin machinery.

Identification of senescence-related molecular subtypes and key genes for prostate cancer.

We identified distinct senescence-related molecular subtypes and critical genes among prostate cancer (PCa) patients undergoing radical prostatectomy (RP) or radical radiotherapy (RT). We conducted all analyses using R software and its suitable packages. Twelve genes, namely, secreted frizzled-related protein 4 (SFRP4), DNA topoisomerase II alpha (TOP2A), pleiotrophin (PTN), family with sequence similarity 107 member A (FAM107A), C-X-C motif chemokine ligand 14 (CXCL14), prostate androgen-regulated mucin-like protein 1 (PARM1), leucine zipper protein 2 (LUZP2), cluster of differentiation 38 (CD38), cartilage oligomeric matrix protein (COMP), vestigial-like family member 3 (VGLL3), apolipoprotein E (APOE), and aldehyde dehydrogenase 2 family member (ALDH2), were eventually used to subtype PCa patients from The Cancer Genome Atlas (TCGA) database and GSE116918, and the molecular subtypes showed good correlations with clinical features. In terms of the tumor immune environment (TME) analysis, compared with cluster 1, cancer-associated fibroblasts (CAFs) scored significantly higher, while endothelial cells scored lower in cluster 2 in TCGA database. There was a statistically significant correlation between both CAFs and endothelial cells with biochemical recurrence (BCR)-free survival for PCa patients undergoing RP. For the GSE116918 database, cluster 2 had significantly lower levels of CAFs and tumor purity and higher levels of stromal, immune, and Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data (ESTIMATE) scores than cluster 1; in addition, patients with high levels of CAFs, stromal scores, immune scores, and ESTIMATE scores and low levels of tumor purity tended to suffer from BCR. Based on the median of differentially expressed checkpoints, high expression of CD96, hepatitis A virus cellular receptor 2 (HAVCR2), and neuropilin 1 (NRP1) in GSE116918 and high expression of CD160 and tumor necrosis factor (ligand) superfamily member 18 (TNFSF18) in TCGA database were associated with a significantly higher risk of BCR than their counterparts. In conclusion, we first constructed distinct molecular subtypes and critical genes for PCa patients undergoing RP or RT from the fresh perspective of senescence.

SFRP4+IGFBP5hi NKT cells induced neural-like cell differentiation to contribute to adenomyosis pain.

Adenomyosis is an estrogen-dependent gynecological disease. The pathogenesis of chronic pain, the main clinical symptom of adenomyosis, remains undefined. As a combination lymphocyte with both T-cell and natural killer (NK)-cell properties, NK T (NKT) cells play a role in immune defense against numerous diseases and modulate cell differentiation. This study analyzed the tissue-cell samples from adenomyosis with or without pain by single-cell sequencing. We found a specific population of secreted frizzled-related protein 4 (SFRP4)+NKT cells and a large amount of undifferentiated multipotent stem cells in the adenomyosis pain group. We discovered that a high expression of IGFBP5 in SFRP4+NKT cells could promote the differentiation of multipotent stem cells into neural-like cells via the single-cell trajectory. Through verification by the sample, we found that the degree of the expression of the neuronal marker NEFM was correlated with the duration of pain in adenomyosis patients. The expression of IGFBP5 was positively correlated with the pain scores of adenomyosis patients. Collectively, these findings suggest that SFRP4+IGFBP5hi NKT cells were capable of converting part of the stem cells into neurogenic cells and inducing adenomyosis pain.

Downregulation of senescence-associated secretory phenotype by knockdown of secreted frizzled-related protein 4 contributes to the prevention of skin aging.

There is growing evidence that the appearance and texture of the skin that is altered during the aging process are considerably enhanced by the accumulation of senescent dermal fibroblasts. These senescent cells magnify aging via an inflammatory, histolytic, and senescence-associated secretory phenotype (SASP). Secreted frizzled-related protein 4 (SFRP4) was previously determined to be expressed in dermal fibroblasts of aging skin, and its increased expression has been shown to promote cellular senescence. However, its role in the SASP remains unknown. We found that SFRP4 was significantly expressed in p16ink4a-positive human skin fibroblasts and that treatment with recombinant SFRP4 promoted SASP and senescence, whereas siRNA knockdown of SFRP4 suppressed SASP. Furthermore, we found that knockdown of SFRP4 in mouse skin ameliorates age-related reduction of subcutaneous adipose tissue, panniculus carnosus muscle layer, and thinning and dispersion of collagen fibers. These findings suggest a potential candidate for the development of new skin rejuvenation therapies that suppress SASP.

SFRP4 Is a Potential Biomarker for the Prognosis and Immunotherapy for Gastric Cancer.

Purpose Secreted frizzled-related protein 4 (SFRP4) is a member of the SFRP family, which functions as either a tumor suppressor or a prooncogenic factor in distinct tumor types. Our research aimed to explore the expression of SFRP4 in gastric cancer, its prognostic significance, and its relationship with immune cell infiltration. Materials and Methods Gastric cancer and paracancerous tissue specimens from surgically resected gastric cancer patients were collected to construct tissue microarrays, and immunohistochemistry was used to detect the expression of SFRP4, PD-L1, CD3+T, CD4+T, and CD8+T in these microarrays. The differential expression of SFRP4 and its relationship with the immune microenvironment were evaluated using the TIMER and TISIDB databases. Finally, patient survival was assessed. Results SFRP4 expression was elevated in gastric cancer tissues and linked to a poor prognosis (P=0.021). The 5-year survival rate for patients with high SFRP4 expression was only 39.81% but reached 60.02% for patients with low SFRP4 expression. Increased SFRP4 expression correlated with high CD8+ T-cell infiltration (P=0.015) and positive PD-L1 expression (P=0.036). High SFRP4 expression was an independent predictor of overall survival (P=0.024 in univariable analysis, P=0.011 in multivariable analysis). Using online databases, we found that SFRP4 expression was higher in gastric cancer tissues and substantially was associated with the immune microenvironment. Conclusion SFRP4 is an oncogenic driver that can predict patient survival time in gastric cancer, as well as an important immune-related factor. SFRP4 may be important for guiding immunotherapy in gastric cancer patients.

SFRP4 and CDX1 Are Predictive Genes for Extragastric Recurrence of Early Gastric Cancer after Curative Resection.

Extragastric recurrence of early gastric cancer (EGC) after curative resection is rare, but prognosis has been poor in previous reports. Recently, single patient classifier (SPC) genes, such as secreted frizzled-related protein 4 (SFRP4) and caudal-type homeobox 1 (CDX1), were associated with prognosis and chemotherapy response in stage II–III gastric cancer. The aim of our study is, therefore, to elucidate predictive factors for extragastric recurrence of EGC after curative resection, including with the expression of SPC genes. We retrospectively reviewed electronic medical records of 1974 patients who underwent endoscopic or surgical curative resection for EGC. We analyzed clinicopathological characteristics to determine predictive factors for extragastric recurrence. Total RNA was extracted from formalin-fixed, paraffin-embedded (FFPE) tumor tissue and amplified by real-time reverse transcription polymerase chain reaction to evaluate expression of SPC genes. Overall incidences of extragastric recurrence were 0.9%. In multivariate analysis, submucosal invasion (odds ratio [OR] = 6.351, p = 0.032) and N3 staging (OR = 171.512, p = 0.012) were independent predictive factors for extragastric recurrence. Mean expression of SFRP4 in extragastric recurrence (−2.8 ± 1.3) was significantly higher than in the control group (−4.3 ± 1.6) (p = 0.047). Moreover, mean expression of CDX1 in extragastric recurrence (−4.6 ± 2.0) was significantly lower than in the control group (−2.4 ± 1.8) (p = 0.025). Submucosal invasion and metastasis of more than seven lymph nodes were independent predictive factors for extragastric recurrence. In addition, SFRP4 and CDX1 may be novel predictive markers for extragastric recurrence of EGC after curative resection.

Secreted frizzled-related protein 4 exerts anti-atherosclerotic effects by reducing inflammation and oxidative stress

Atherosclerosis and its sequelae, such as coronary artery disease (CAD), are the most common diseases worldwide and the leading causes of morbidity and mortality in most countries. Our previous studies have shown that circulating secreted frizzled-related protein 4 (SFRP4) levels are increased in patients with CAD. However, the role of SFRP4 in the development of atherosclerosis remains unclear; thus, the purpose of this study was to determine the effect of SFRP4 on high-fat diet (HFD)-induced atherosclerosis and explore the possible mechanisms. In this study, we found for the first time that administration of recombinant SFRP4 alleviates atherosclerosis in ApoE−/− mice by reducing inflammation and oxidative stress. In addition, the anti-atherosclerotic effect of SFRP4 was associated with inhibition of the Wnt/β-catenin signaling pathway, and Wnt1 overexpression abolished the anti-atherosclerotic effects of SFRP4. Taken together, our results highlight the potential beneficial effect of SFRP4 as a therapeutic agent for atherosclerosis and CAD.