The Multifaceted S100A4 Protein in Cancer and Inflammation

S100A4 exerts neuroprotective effects by attenuating blood-brain barrier disruption and oxidative stress via the PI3K/Akt/Nrf2 axis in ischemic stroke

Ischemic stroke is a major cause of disability and mortality worldwide, with oxidative stress and blood-brain barrier (BBB) injury playing crucial roles in its pathogenesis. Our RNA sequencing results revealed that S100 calcium-binding protein A4 (S100A4) is highly expressed in the middle cerebral artery occlusion (MCAO) mouse model. We analyzed S100A4 expression in ischemic stroke patients and in mice subjected to the MCAO model. Moreover, using adeno-associated virus (AAV)-mediated knockdown of S100A4 in mice, we evaluated its effects on neurological deficits, BBB integrity, and oxidative stress in MCAO mice. Bioinformatic analyses explored the potential downstream pathways of S100A4.S100A4 expression was significantly elevated in the serum of ischemic stroke patients and brain tissues of MCAO mice. AAV-mediated knockdown of S100A4 exacerbated neurological deficits, BBB disruption, and oxidative stress in MCAO mice. The upregulation of S100A4 mitigated these outcomes, which were facilitated through the stimulation of the PI3K/Akt/Nrf2 signaling cascade.Our results illustrate that S100A4 plays a protective role in preventing neuronal damage during ischemic stroke by reducing oxidative stress and preserving BBB integrity through the PI3K/Akt/Nrf2 pathway. This highlights its promise as a potential therapeutic approach for ischemic stroke.

S100A4 promotes experimental autoimmune encephalomyelitis by impacting microglial inflammation through TLR4/NF-κB signaling pathway

Multiple sclerosis (MS) is a neurodegenerating autoimmune disease with no clinical cure currently. The calcium-binding protein S100A4 has been demonstrated to exert regulatory roles in inflammatory disorders including MS. However, the precise mechanisms by which S100A4 regulates neuroinflammation in MS remains unknown. To investigate the regulatory effect of S100A4 on microglial inflammation and its impact on neuroinflammation, the mouse-derived microglia cell line BV2 cells were infected with lentivirus to knockout S100A4 for in vitro studies. Wild-type (WT) and S100A4-/- mice were induced to develop experimental autoimmune encephalomyelitis (EAE), an animal model of MS, for in vivo investigation. Results indicated that the frequencies of microglia in the spinal cord and brain and the expression of S100A4 in these tissues varied kinetically along with the progression of the disease in mice with EAE. S100A4-/- mice presented ameliorated clinical scores of EAE and exhibited less severe EAE signs, including inflammatory cell infiltration in the spinal cord and brain and demyelination of the spinal cord. Moreover, these mice demonstrated overall reduced levels of inflammatory cytokines in the spinal cord and brain. Compromised systematic inflammatory responses including circulating cytokines and frequencies of immune cells in the spleen were also observed in these mice. In addition, both exogenous and endogenous S100A4 could promote the microglial inflammation, affect the polarization of microglia and enhance inflamed microglia-mediated apoptosis of neuronal cells through TLR4/NF-κB signaling pathway. Thus, S100A4 may participate in the regulation of neuroinflammation at least partly through regulating the inflammation of microglia.

Role of the Receptor for Advanced Glycation End Products (RAGE) and Its Ligands in Inflammatory Responses

Since its discovery in 1992, the receptor for advanced glycation end products (RAGE) has emerged as a key receptor in many pathological conditions, especially in inflammatory conditions. RAGE is expressed by most, if not all, immune cells and can be activated by many ligands. One characteristic of RAGE is that its ligands are structurally very diverse and belong to different classes of molecules, making RAGE a promiscuous receptor. Many of RAGE ligands are damaged associated molecular patterns (DAMPs) that are released by cells under inflammatory conditions. Although RAGE has been at the center of a lot of research in the past three decades, a clear understanding of the mechanisms of RAGE activation by its ligands is still missing. In this review, we summarize the current knowledge of the role of RAGE and its ligands in inflammation.

An integrated single-cell atlas of blood immune cells in aging

Recent advances in single-cell technologies have facilitated studies on age-related alterations in the immune system. However, previous studies have often employed different marker genes to annotate immune cell populations, making it challenging to compare results. In this study, we combined seven single-cell transcriptomic datasets, comprising more than a million cells from one hundred and three donors, to create a unified atlas of human peripheral blood mononuclear cells (PBMC) from both young and old individuals. Using a consistent set of marker genes for immune cell annotation, we standardized the classification of immune cells and assessed their prevalence in both age groups. The integrated dataset revealed several consistent trends related to aging, including a decline in CD8+ naive T cells and MAIT cells and an expansion of non-classical monocyte compartments. However, we observed significant variability in other cell types. Our analysis of the long non-coding RNA MALAT1hi T cell population, previously implicated in age-related T cell exhaustion, showed that this population is highly heterogeneous with a mixture of naïve-like and memory-like cells. Despite substantial variation among the datasets when comparing gene expression between age groups, we identified a high-confidence signature of CD8+ naive T cell aging marked by an increased expression of pro-inflammatory genes. In conclusion, our study emphasizes the importance of standardizing existing single-cell datasets to enable the comprehensive examination of age-related cellular changes across multiple datasets.

A mucosal vaccine formulation against tuberculosis by exploiting the adjuvant activity of S100A4-A damage-associated molecular pattern molecule

Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), remains one of the top three causes of death. Currently, the only licensed vaccine against TB is the bacillus Calmette-Guerin (BCG), which lacks efficacy in preventing and controlling pulmonary TB in adults. We aimed to evaluate a nasal TB vaccine formulation composed of the Mtb-specific vaccine antigen ESAT-6, an Mtb-associated protein that can trigger protective immune responses, and S100A4, a recently characterized novel mucosal adjuvant. Mice were intranasally given recombinant ESAT-6 in the presence or absence of S100A4 as an adjuvant. We have provided experimental evidence demonstrating that S100A4 admixed to ESAT-6 could induce Mtb-specific adaptive immune responses after intranasal immunization. S100A4 remarkably augmented the levels of anti-ESAT-6 IgG in serum and IgA in mucosal sites, including lung exudates, bronchoalveolar lavage fluid (BALF) and nasal lavage. Furthermore, in both lung and spleen tissues, S100A4 strongly promoted ESAT-6-specific expansion of CD4 T cells. Both CD4 and CD8 T cells from these tissues expressed increased levels of IFN-γ, TNF-α, and IL-17, cytokines critical for antimicrobial activity. Antigen-reencounter-induced T cell proliferative responses, a key vaccine performance indicator, were augmented in the spleen of S100A4-adjuvanted mice. Furthermore, CD8 T cells from the spleen and lung tissues of these mice expressed higher levels of granzyme B upon antigen re-stimulation. S100A4-adjuvanted immunization may predict good mucosal protection against TB.

Screening and identification of key biomarkers associated with endometriosis using bioinformatics and next-generation sequencing data analysis

Background

Endometriosis is a common cause of endometrial-type mucosa outside the uterine cavity with symptoms such as painful periods, chronic pelvic pain, pain with intercourse and infertility. However, the early diagnosis of endometriosis is still restricted. The purpose of this investigation is to identify and validate the key biomarkers of endometriosis.

Methods

Next-generation sequencing dataset GSE243039 was obtained from the Gene Expression Omnibus database, and differentially expressed genes (DEGs) between endometriosis and normal control samples were identified. After screening of DEGs, gene ontology (GO) and REACTOME pathway enrichment analyses were performed. Furthermore, a protein–protein interaction (PPI) network was constructed and modules were analyzed using the Human Integrated Protein–Protein Interaction rEference database and Cytoscape software, and hub genes were identified. Subsequently, a network between miRNAs and hub genes, and network between TFs and hub genes were constructed using the miRNet and NetworkAnalyst tool, and possible key miRNAs and TFs were predicted. Finally, receiver operating characteristic curve analysis was used to validate the hub genes.

Results

A total of 958 DEGs, including 479 upregulated genes and 479 downregulated genes, were screened between endometriosis and normal control samples. GO and REACTOME pathway enrichment analyses of the 958 DEGs showed that they were mainly involved in multicellular organismal process, developmental process, signaling by GPCR and muscle contraction. Further analysis of the PPI network and modules identified 10 hub genes, including vcam1, snca, prkcb, adrb2, foxq1, mdfi, actbl2, prkd1, dapk1 and actc1. Possible target miRNAs, including hsa-mir-3143 and hsa-mir-2110, and target TFs, including tcf3 (transcription factor 3) and clock (clock circadian regulator), were predicted by constructing a miRNA-hub gene regulatory network and TF-hub gene regulatory network.

Conclusions

This investigation used bioinformatics techniques to explore the potential and novel biomarkers. These biomarkers might provide new ideas and methods for the early diagnosis, treatment and monitoring of endometriosis.

Role of innate host defense proteins in oral cancerogenesis

It is nowadays well accepted that chronic inflammation plays a pivotal role in tumor initiation and progression. Under this aspect, the oral cavity is predestined to examine this connection because periodontitis is a highly prevalent chronic inflammatory disease and oral squamous cell carcinomas are the most common oral malignant lesions. In this review, we describe how particular molecules of the human innate host defense system may participate as molecular links between these two important chronic noncommunicable diseases (NCDs). Specific focus is directed toward antimicrobial polypeptides, such as the cathelicidin LL-37 and human defensins, as well as S100 proteins and alarmins. We report in which way these peptides and proteins are able to initiate and support oral tumorigenesis, showing direct mechanisms by binding to growth-stimulating cell surface receptors and/or indirect effects, for example, inducing tumor-promoting genes. Finally, bacterial challenges with impact on oral cancerogenesis are briefly addressed.

A combined transcriptomics and proteomics approach reveals S100A4 as a potential biomarker for Graves' orbitopathy

Background

There are no reliable biomarkers to identify Graves' disease patients who will develop severe Graves' orbitopathy (GO). We hypothesize that integrating various omics platforms can enhance our understanding of disease mechanisms and uncover potential biomarkers. This study aimed to (1) elucidate the differential gene expression profile of orbital fibroblasts in GO during early adipogenesis to better understand disease mechanisms and (2) compare tear protein profiles from our earlier study and the transcriptome profiles of orbital fibroblasts (OFs) to identify possible biomarkers of the disease.

Methods

OFs were grown from orbital adipose tissue obtained from nine GO patients (three for discovery and six for validation experiments). Total RNA was extracted from OFs on day 0 as the baseline for each sample and from differentiated OFs on days 4 and 8. Protein-protein interaction (PPI) analysis and functional enrichment analysis were also carried out. The differentially expressed genes (DEGs) from the RNA sequencing experiments were then compared to the full tear proteome profile from the author's previous study, which examined the tear protein changes of GO patients based on fold change > 1.6 or < -1.6. FDR < 0.05 was applied within all datasets. Further validation of S100 calcium-binding protein A4 (S100A4) downregulation in GO was performed via quantitative real-time PCR (qPCR).

Results

The whole transcriptomic analysis revealed 9 upregulated genes and 15 downregulated genes in common between the discovery and validation experiments. From the PPI network analysis, an interaction network containing six identified DEGs (ALDH2, MAP2K6, MT2A, SOCS3, S100A4, and THBD) was observed. The functional enrichment network analysis identified a set of genes related to oxysterol production. S100A4 was found to be consistently downregulated in both our transcriptome studies and the full-tear proteome profile from the author's previous study.

Conclusion

Our study identified several DEGs and potential gene pathways in GO patients, which concurred with the results of other studies. Tear S100A4 may serve as a biomarker for the propensity to develop thyroid eye disease (TED) in patients with autoimmune thyroid disease (AITD) before clinical manifestation and should be confirmed in future studies.

Prognostic Protein Biomarker Screening for Thyroid Carcinoma Based on Cancer Proteomics Profiles

Thyroid carcinoma (THCA) ranks among the most prevalent cancers globally. Integrating advanced genomic and proteomic analyses to construct a protein-based prognostic model promises to identify effective biomarkers and explore new therapeutic avenues. In this study, proteomic data from The Cancer Proteomics Atlas (TCPA) and clinical data from The Cancer Genome Atlas (TCGA) were utilized. Using Kaplan-Meier, Cox regression, and LASSO penalized Cox analyses, we developed a prognostic risk model comprising 13 proteins (S100A4, PAI1, IGFBP2, RICTOR, B7-H3, COLLAGENVI, PAR, SNAIL, FAK, Connexin-43, Rheb, EVI1, and P90RSK_pT359S363). The protein prognostic model was validated as an independent predictor of survival time in THCA patients, based on risk curves, survival analysis, receiver operating characteristic curves and independent prognostic analysis. Additionally, we explored the immune cell infiltration and tumor mutational burden (TMB) related to these features. Notably, our study proved a novel approach for predicting treatment responses in THCA patients, including those undergoing chemotherapy and targeted therapy.

Using a pan-cancer atlas to investigate tumour associated macrophages as regulators of immunotherapy response

The paradigm for macrophage characterization has evolved from the simple M1/M2 dichotomy to a more complex model that encompasses the broad spectrum of macrophage phenotypic diversity, due to differences in ontogeny and/or local stimuli. We currently lack an in-depth pan-cancer single cell RNA-seq (scRNAseq) atlas of tumour-associated macrophages (TAMs) that fully captures this complexity. In addition, an increased understanding of macrophage diversity could help to explain the variable responses of cancer patients to immunotherapy. Our atlas includes well established macrophage subsets as well as a number of additional ones. We associate macrophage composition with tumour phenotype and show macrophage subsets can vary between primary and metastatic tumours growing in sites like the liver. We also examine macrophage-T cell functional cross talk and identify two subsets of TAMs associated with T cell activation. Analysis of TAM signatures in a large cohort of immune checkpoint inhibitor-treated patients (CPI1000 + ) identify multiple TAM subsets associated with response, including the presence of a subset of TAMs that upregulate collagen-related genes. Finally, we demonstrate the utility of our data as a resource and reference atlas for mapping of novel macrophage datasets using projection. Overall, these advances represent an important step in both macrophage classification and overcoming resistance to immunotherapies in cancer.

Effect of Anti-S100A4 Monoclonal Antibody Treatment on Experimental Skin Fibrosis and Systemic Sclerosis-Specific Transcriptional Signatures in Human Skin

OBJECTIVE

S100A4 is a DAMP protein. S100A4 is overexpressed in patients with systemic sclerosis (SSc), and levels correlate with organ involvement and disease activity. S100A4-/- mice are protected from fibrosis. The aim of this study was to assess the antifibrotic effects of anti-S100A4 monoclonal antibody (mAb) in murine models of SSc and in precision cut skin slices of patients with SSc.

METHODS

The effects of anti-S100A4 mAbs were evaluated in a bleomycin-induced skin fibrosis model and in Tsk-1 mice with a therapeutic dosing regimen. In addition, the effects of anti-S100A4 mAbs on precision cut SSc skin slices were analyzed by RNA sequencing.

RESULTS

Inhibition of S100A4 was effective in the treatment of pre-established bleomycin-induced skin fibrosis and in regression of pre-established fibrosis with reduced dermal thickening, myofibroblast counts, and collagen accumulation. Transcriptional profiling demonstrated targeting of multiple profibrotic and proinflammatory processes relevant to the pathogenesis of SSc on targeted S100A4 inhibition in a bleomycin-induced skin fibrosis model. Moreover, targeted S100A4 inhibition also modulated inflammation- and fibrosis-relevant gene sets in precision cut SSc skin slices in an ex vivo trial approach. Selected downstream targets of S100A4, such as AMP-activated protein kinase, calsequestrin-1, and phosphorylated STAT3, were validated on the protein level, and STAT3 inhibition was shown to prevent the profibrotic effects of S100A4 on fibroblasts in human skin.

CONCLUSION

Inhibition of S100A4 confers dual targeting of inflammatory and fibrotic pathways in complementary mouse models of fibrosis and in SSc skin. These effects support the further development of anti-S100A4 mAbs as disease-modifying targeted therapies for SSc.

Joint Hypermobility Syndrome and Membrane Proteins: A Comprehensive Review

Ehlers-Danlos syndromes (EDSs) constitute a heterogeneous group of connective tissue disorders characterized by joint hypermobility, skin hyperextensibility, and tissue fragility. Asymptomatic EDSs, joint hypermobility without associated syndromes, EDSs, and hypermobility spectrum disorders are the commonest phenotypes associated with joint hypermobility. Joint hypermobility syndrome (JHS) is a connective tissue disorder characterized by extreme flexibility of the joints, along with pain and other symptoms. JHS can be a sign of a more serious underlying genetic condition, such as EDS, which affects the cartilage, bone, fat, and blood. The exact cause of JHS could be related to genetic changes in the proteins that add flexibility and strength to the joints, ligaments, and tendons, such as collagen. Membrane proteins are a class of proteins embedded in the cell membrane and play a crucial role in cell signaling, transport, and adhesion. Dysregulated membrane proteins have been implicated in a variety of diseases, including cancer, cardiovascular disease, and neurological disorders; recent studies have suggested that membrane proteins may also play a role in the pathogenesis of JHS. This article presents an exploration of the causative factors contributing to musculoskeletal pain in individuals with hypermobility, based on research findings. It aims to provide an understanding of JHS and its association with membrane proteins, addressing the clinical manifestations, pathogenesis, diagnosis, and management of JHS.

S100A4-neutralizing monoclonal antibody 6B12 counteracts the established experimental skin fibrosis induced by bleomycin

OBJECTIVES

Our previous studies have demonstrated that the Damage Associated Molecular Pattern (DAMP) protein, S100A4, is overexpressed in the involved skin and peripheral blood of patients with SSc. It is associated with skin and lung involvement, and disease activity. By contrast, lack of S100A4 prevented the development of experimental dermal fibrosis. Herein we aimed to evaluate the effect of murine anti-S100A4 mAb 6B12 in the treatment of preestablished experimental dermal fibrosis.

METHODS

The effects of 6B12 were assessed at therapeutic dosages in a modified bleomycin-induced dermal fibrosis mouse model by evaluating fibrotic (dermal thickness, proliferation of myofibroblasts, hydroxyproline content, phosphorylated Smad3-positive cell count) and inflammatory (leukocytes infiltrating the lesional skin, systemic levels of selected cytokines and chemokines) outcomes, and transcriptional profiling (RNA sequencing).

RESULTS

Treatment with 7.5 mg/kg 6B12 attenuated and might even reduce pre-existing dermal fibrosis induced by bleomycin as evidenced by reduction in dermal thickness, myofibroblast count and collagen content. These antifibrotic effects were mediated by the downregulation of TGF-β/Smad signalling and partially by reducing the number of leukocytes infiltrating the lesional skin and decrease in the systemic levels of IL-1α, eotaxin, CCL2 and CCL5. Moreover, transcriptional profiling demonstrated that 7.5 mg/kg 6B12 also modulated several profibrotic and proinflammatory processes relevant to the pathogenesis of SSc.

CONCLUSION

Targeting S100A4 by the 6B12 mAb demonstrated potent antifibrotic and anti-inflammatory effects on bleomycin-induced dermal fibrosis and provided further evidence for the vital role of S100A4 in the pathophysiology of SSc.

S100A4/NF-κB axis mediates the anticancer effect of epigallocatechin-3-gallate in platinum-resistant ovarian cancer

Resistance to cisplatin (cis-dichlorodiamineplatinum, DDP) in ovarian cancer is a significant clinical challenge. Epigallocatechin-3-gallate (EGCG) has shown promise in cancer therapy. However, its effects on DDP-resistant ovarian cancer remain understudied. This study aims to assess the impact of EGCG on DDP-resistant cells and elucidate the associated molecular mechanisms. DDP-resistant cell lines were utilized for biological characterization. EGCG effectively inhibited proliferation, mobility, and induced apoptosis in OC/DDP cells. It downregulated the expression of S100A4 and NF-κB while upregulating p53 expression. These effects were reversed upon overexpression of S100A4 or NF-κB. In vivo experiments confirmed tumor inhibition and KI67 inhibition by EGCG. Moreover, EGCG downregulated the expression of S100A4 and NF-κB while upregulating p53 in xenograft mice compared to those without EGCG treatment. This study suggests that EGCG suppresses cancer progression through the S100A4/NF-κB signaling pathway, involving interaction with p53. EGCG holds potential as an anticancer candidate for OC/DDP.

T Cell Features in Glioblastoma May Guide Therapeutic Strategies to Overcome Microenvironment Immunosuppression

Glioblastoma (GBM) is the most aggressive and lethal primary brain tumor, bearing a survival estimate below 10% at five years, despite standard chemoradiation treatment. At recurrence, systemic treatment options are limited and the standard of care is not well defined, with inclusion in clinical trials being highly encouraged. So far, the use of immunotherapeutic strategies in GBM has not proved to significantly improve patients' prognosis in the treatment of newly diagnosed GBM, nor in the recurrent setting. Probably this has to do with the unique immune environment of the central nervous system, which harbors several immunosuppressive/pro-tumorigenic factors, both soluble (e.g., TGF-β, IL-10, STAT3, prostaglandin E2, and VEGF) and cellular (e.g., Tregs, M2 phenotype TAMs, and MDSC). Here we review the immune composition of the GBMs microenvironment, specifically focusing on the phenotype and function of the T cell compartment. Moreover, we give hints on the therapeutic strategies, such as immune checkpoint blockade, vaccinations, and adoptive cell therapy, that, interacting with tumor-infiltrating lymphocytes, might both target in different ways the tumor microenvironment and potentiate the activity of standard therapies. The path to be followed in advancing clinical research on immunotherapy for GBM treatment relies on a twofold strategy: testing combinatorial treatments, aiming to restore active immune anti-tumor responses, tackling immunosuppression, and additionally, designing more phase 0 and window opportunity trials with solid translational analyses to gain deeper insight into the on-treatment shaping of the GBM microenvironment.

Anti-S100A4 antibody administration alleviates bronchial epithelial-mesenchymal transition in asthmatic mice

We elucidated the effect of S100A4 on airway remodeling by regulating airway inflammation and epithelial-mesenchymal transition (EMT) in mouse models of asthma. Asthmatic mouse models were established by sensitization and challenged with ovalbumin (OVA). Anti-S100A4 antibody or control IgG antibody was administered daily before the OVA challenge. After the last challenge, airway inflammation and airway hyperresponsiveness were measured; lung tissues and bronchoalveolar lavage fluid (BALF) were harvested. Lung tissue sections were stained and evaluated for pathological changes. Levels of inflammatory cytokines were measured using ELISA. Levels of S100A4 and EMT markers were determined via western blotting analysis. Human bronchial epithelial cells were stimulated with 100 mg/mL house dust mites (HDMs) to evaluate the effect of S100A4 downregulation on EMT in vitro. S100A4 was increased in lung tissues and BALF from asthmatic mice. The asthmatic mice presented airway hyperresponsiveness, airway inflammation, and airway remodeling. After anti-S100A4 antibody administration, pathophysiological signs, including airway hyperresponsiveness and increased infiltration of inflammatory cells, were attenuated. Additionally, anti-S100A4 administration downregulated vimentin and α-SMA expression and upregulated E-cadherin expression in OVA-challenged mice. S100A4 downregulation also inhibited EMT process in HDM-stimulated 16HBE cells. Anti-S100A4 antibody administration alters airway remodeling by preventing EMT in mouse models of asthma.

S100 Proteins in the Pathogenesis of Psoriasis and Atopic Dermatitis

The skin, the outermost layer of the human body, is exposed to various external stimuli that cause inflammatory skin reactions. These external stimulants trigger external epithelial cell damage and the release of intracellular substances. Following cellular damage or death, intracellular molecules are released that enhance tissue inflammation. As an important substance released from damaged cells, the S100 protein is a low-molecular-weight acidic protein with two calcium-binding sites and EF-hand motif domains. S100 proteins are widely present in systemic organs and interact with other proteins. Recent studies revealed the involvement of S100 in cutaneous inflammatory disorders, psoriasis, and atopic dermatitis. This review provides detailed information on the interactions among various S100 proteins in inflammatory diseases.

Clinical and pathogenic significance of S100A4 overexpression in systemic sclerosis

OBJECTIVES

We have studied the damage-associated molecular pattern protein S100A4 as a driver of fibroblast activation in systemic sclerosis (SSc).

METHODS

S100A4 protein concentration was measured by ELISA in serum of SSc (n=94) and healthy controls (n=15). Protein expression in skin fibroblast cultures from diffuse cutaneous SSc (SScF, n=6) and healthy controls (normal fibroblasts (NF), n=6) was assessed. Recombinant S100A4 and a high affinity anti-S100A4 neutralising monoclonal antibody (AX-202) were tested on SScF and NF.

RESULTS

Median (range) S100A4 (ng/mL) was higher in serum of SSc (89.9 (15.0-240.0)) than healthy controls (71.4 (7.9-131.8); p=0.027). There was association with SSc-interstitial lung disease (p=0.025, n=55), scleroderma renal crisis (p=0.026, n=4). Median (range) S100A4 (ng/mL) was higher in culture supernatants of SScF (4.19 (0.52-8.42)) than NF controls (0.28 (0.02-3.29); p<0.0001). AX-202 reduced the constitutive profibrotic gene and protein expression phenotype of SScF. Genome-wide RNA sequencing analysis identified an S100A4 activated signature in NF overlapping the hallmark gene expression signature of SScF. Thus, 464 differentially expressed genes (false discovery rate (FDR) <0.001 and fold change (FC) >1.5) induced in NF by S100A4 were also constitutively overexpressed, and downregulated by AX-202, in SScF. Pathway mapping of these S100A4 dependent genes in SSc showed the most significant enriched Kegg pathways (FDR <0.001) were regulation of stem cell pluripotency (4.6-fold) and metabolic pathways (1.9-fold).

CONCLUSION

Our findings provide compelling evidence for a profibrotic role for S100A4 in SSc and suggest that serum level may be a biomarker of major organ manifestations and disease severity. This study supports examining the therapeutic potential of targeting S100A4 in SSc.

Ring finger protein 215 is a potential prognostic biomarker involved in immune infiltration and angiogenesis in colorectal cancer

The prognostic value of ring finger protein 215 (RNF215) in colorectal cancer (CRC) is unclear. Herein, the present study aimed to investigate the precise value of RNF215 based on CRC datasets from The Cancer Genome Atlas (TCGA) and clinical cases. CRC patient data was collected from TCGA and clinical samples from the Department of Pathology, Shanghai Fifth People's Hospital, Fudan University (Shanghai, China). Logistic regression analysis was used to investigate the correlations between RNF215 and clinicopathological characteristics. The predictive value of RNF215 for the clinical outcome of CRC was determined using Kaplan-Meier curves and Cox regression. Gene set enrichment analysis (GSEA), single-sample GSEA (ssGSEA), and angiogenesis analysis were also conducted to investigate the biological role of RNF215. Immunohistochemistry was conducted to validate the results. The results of the present study confirmed that RNF215 protein expression was significantly associated with age, lymphatic invasion, and overall survival (OS). Univariate analysis showed that upregulation of RNF215 in CRC was significantly associated with age and lymphatic invasion. Kaplan-Meier survival analysis revealed that high RNF215 expression predicted poorer OS and disease-specific survival. A total of nine experimentally detected RNF215-binding proteins were identified with the STRING tool and Cytoscape software. GSEA suggested that RNF215 was associated with several important pathways involved in tumor occurrence, including the Kyoto Encyclopedia of Genes and Genomes MAPK signaling pathway and the WikiPathway RAS signaling pathway. ssGSEA confirmed that RNF215 was significantly expressed in natural killer cells, CD8 T cells and T helper cells. Angiogenesis analysis revealed that numerous angiogenesis-related genes had the same expression trend as RNF215 in CRC. The immunostaining results indicated that RNF215 expression was significantly higher in CRC tissues than in corresponding normal tissues. In conclusion, increased RNF215 expression may be a potential molecular marker predictive of poor survival and a treatment target in CRC. In addition, RNF215 may participate in the formation of CRC through a variety of signaling pathways.

Single cell RNA-sequencing of human precision-cut lung slices: A novel approach to study the effect of vaping and viral infection on lung health

Vaping is an increasing health threat in the US and worldwide. The damaging impact of vaping on the human distal lung has been highlighted by the recent epidemic of electronic cigarette or vaping use-associated lung injury (EVALI). The pathogenesis of EVALI remains incompletely understood, due to a paucity of models that recapitulate the structural and functional complexity of the human distal lung and the still poorly defined culprit exposures to vaping products and respiratory viral infections. Our aim was to establish the feasibility of using single cell RNA-sequencing (scRNA-seq) technology in human precision-cut lung slices (PCLS) as a more physiologically relevant model to better understand how vaping regulates the antiviral and pro-inflammatory response to influenza A virus infection. Normal healthy donor PCLS were treated with vaping extract and influenza A viruses for scRNA-seq analysis. Vaping extract augmented host antiviral and pro-inflammatory responses in structural cells such as lung epithelial cells and fibroblasts, as well as in immune cells such as macrophages and monocytes. Our findings suggest that human distal lung slice model is useful to study the heterogeneous responses of immune and structural cells under EVALI conditions, such as vaping and respiratory viral infection.

Ficolin A knockout alleviates sepsis-induced severe lung injury in mice by restoring gut Akkermansia to inhibit S100A4/STAT3 pathway

Acute lung injury (ALI) is a life-threatening disease with high morbidity and mortality. Our previous results demonstrated that Ficolin A (FcnA) protected against lipopolysaccharide (LPS)-induced mild ALI via activating complement, however the mechanism of severe lung damage caused by sepsis remains unclear. This study aimed to investigate whether FcnA modulated gut microbiota to affect the progression of sepsis-induced severe ALI. Fcna^-/- and Fcnb^-/- C57BL/6 mice were applied to establish the ALI model by injection of LPS intraperitoneally. Mice were treated with antibiotics, fecal microbiota transplantation (FMT), and intratracheal administration of recombinant protein S100A4. Changes in body weight of mice were recorded, and lung injury were assessed. Then lung tissue wet/dry weight was calculated. We found knockout of FcnA, but not FcnB, alleviated sepsis-induced severe ALI evidenced by increased body weight change, decreased wet/dry weight of lung tissue, reduced inflammatory infiltration, decreased lung damage score, decreased Muc-2, TNF-α, IL-1β, IL-6, and Cr levels, and increased sIgA levels. Furthermore, knockout of FcnA restored gut microbiota homeostasis in mice. Correlation analysis showed that Akkermansia was significantly negatively associated with TNF-α, IL-1β, and IL-6 levels in serum and bronchoalveolar lavage fluid (BALF). Moreover, knockout of FcnA regulated gut microbiota to protect ALI through S100A4. Finally, we found knockout of FcnA alleviated ALI by inhibiting S100A4 via gut Akkermansia in mice, which may provide further insights and new targets into treating sepsis-induced severe lung injury.

Angiogenesis regulators S100A4, SPARC and SPP1 correlate with macrophage infiltration and are prognostic biomarkers in colon and rectal cancers

Introduction

Increasing evidence suggests that it is necessary to find effective and robust clinically validated prognostic biomarkers that can identify "high-risk" colorectal cancer (CRC) patients. Currently, available prognostic factors largely include clinical-pathological parameters and focus on the cancer stage at the time of diagnosis. Among cells of tumor microenvironment (TME) only Immunoscore classifier based on T lymphocytes showed high predictive value.

Methods

In the present study, we performed the complex analysis of mRNA and protein expression of crucial regulators of tumor angiogenesis and tumor progression, expressed by tumor-associated macrophages (TAMs): S100A4, SPP1 and SPARC. Colon and rectal cancer patients were investigated independently and in a combined cohort (CRC). For mRNA expression, we analyzed RNA sequencing data obtained from TCGA (N=417) and GEO (N=92) cohorts of colorectal cancer patients. For protein expression, we performed IHC digital quantification of tumor tissues obtained from 197 patients with CRC treated in the Department of abdominal oncology in Clinics of Tomsk NRMC.

Results

High S100A4 mRNA expression accurately predicted poor survival for patients with CRC independently of cancer type. SPARC mRNA level was independent prognostic factors for survival in colon but not in rectal cancer. SPP1 mRNA level had significant predictive value for survival in both rectal and colon cancers. Analysis of human CRC tissues revealed that S100A4, SPP1 and SPARC are expressed by stromal compartments, in particular by TAMs, and have a strong correlation with macrophage infiltration. Finally, our results indicate that chemotherapy-based treatment can change the predictive direction of S100A4 for rectal cancer patients. We found that S100A4 stromal levels were higher in patients with better response to neoadjuvant chemotherapy/chemoradiotherapy, and S100A4 mRNA levels predicted better DFS among non-responders.

Discussion

These findings can help improve the prognosis of patients with CRC based on S100A4, SPP1 and SPARC expression levels.

Differential Expression of MED12-Associated Coding RNA Transcripts in Uterine Leiomyomas

Recent studies have demonstrated that somatic MED12 mutations in exon 2 occur at a frequency of up to 80% and have a functional role in leiomyoma pathogenesis. The objective of this study was to elucidate the expression profile of coding RNA transcripts in leiomyomas, with and without these mutations, and their paired myometrium. Next-generation RNA sequencing (NGS) was used to systematically profile the differentially expressed RNA transcripts from paired leiomyomas (n = 19). The differential analysis indicated there are 394 genes differentially and aberrantly expressed only in the mutated tumors. These genes were predominantly involved in the regulation of extracellular constituents. Of the differentially expressed genes that overlapped in the two comparison groups, the magnitude of change in gene expression was greater for many genes in tumors bearing MED12 mutations. Although the myometrium did not express MED12 mutations, there were marked differences in the transcriptome landscape of the myometrium from mutated and non-mutated specimens, with genes regulating the response to oxygen-containing compounds being most altered. In conclusion, MED12 mutations have profound effects on the expression of genes pivotal to leiomyoma pathogenesis in the tumor and the myometrium which could alter tumor characteristics and growth potential.

SVCT2-mediated ascorbic acid uptake buffers stress responses via DNA hydroxymethylation reprogramming of S100 calcium-binding protein A4 gene

Vitamin C, a key antioxidant in the central nervous system, cycles between ascorbic acid and dehydroascorbic acid under pathophysiological conditions. Clinical evidence supports that the absence of vitamin C may be linked to depressive symptoms, but much less is known about the mechanism. Herein, we show that chronic stress disrupts the expression of ascorbic acid transporter, sodium-dependent vitamin C transport 2, and induces a deficiency in endogenous ascorbic acid in the medial prefrontal cortex, leading to depressive-like behaviors by disturbing redox-dependent DNA methylation reprogramming. Attractively, ascorbic acid (100 mg/kg-1000 mg/kg, intraperitoneal injection, as bioequivalent of an intravenous drip dose of 0.48 g-4.8 g ascorbic acid per day in humans) produces rapid-acting antidepressant effects via triggering DNA demethylation catalyzed by ten-eleven translocation dioxygenases. In particular, the mechanistic studies by both transcriptome sequencing and methylation sequencing have shown that S100 calcium binding protein A4, a potentially protective factor against oxidative stress and brain injury, mediates the antidepressant activity of ascorbic acid via activating erb-b2 receptor tyrosine kinase 4 (ErbB4)-brain derived neurotrophic factor (BDNF) signaling pathway. Overall, our findings reveal a novel nutritional mechanism that couples stress to aberrant DNA methylation underlying depressive-like behaviors. Therefore, application of vitamin C may be a potential strategy for the treatment of depression.

Predictive value of S100A4 in eosinophilic chronic rhinosinusitis with nasal polyps

OBJECTIVE

S100A4 is a pro-inflammatory mediator which has been implicated in airway inflammatory diseases. However, its role in chronic rhinosinusitis with nasal polyps (CRSwNP) remains unclear. The purpose of this study is to determine the expression of S100A4 and evaluate its potential value in distinguishing its endotypes.

METHODS

Sixty CRSwNP patients, 30 chronic rhinosinusitis without nasal polyps (CRSsNP) patients, and 30 healthy controls (HC) were enrolled in this study, and serum and tissue samples were collected. Serum and tissue S100A4 levels were detected by enzyme-linked immunosorbent assay, reverse transcription-polymerase chain reaction, western blotting and immunofluorescence. Their clinical values in predicting postoperative recurrence of CRSwNP were evaluated by multivariate analysis and ROC curves.

RESULTS

Serum levels of S100A4 were notably increased in the CRSwNP group than in the CRSsNP and HC groups (p < 0.05), and positively correlated with tissue and peripheral eosinophil count and percentage (p < 0.05). The serum S100A4 concentrations were significantly elevated in the Eos CRSwNP group in comparison with the non-Eos CRSwNP group (p < 0.05). Multivariate analysis and ROC curve presented that serum S100A4 levels were associated with CRSwNP endotypes. Additionally, tissue S100A4 mRNA and protein levels were significantly enhanced in the CRSwNP group than in the HC group and CRSsNP group, especially in the Eos CRSwNP group.

CONCLUSION

Our results demonstrated that the S100A4 expression was increased in CRSwNP patients and associated with the endotypes. S100A4 could be a serologic biomarker for evaluating tissue eosinophilic inflammation and predicting endotypes in CRSwNP patients.

iTRAQ Proteomics Identified the Potential Biomarkers of Coronary Artery Lesion in Kawasaki Disease and In Vitro Studies Demonstrated That S100A4 Treatment Made HCAECs More Susceptible to Neutrophil Infiltration

Coronary artery lesions (CAL) are a major complication of Kawasaki disease (KD). The early prediction of CAL enables the medical personnel to apply adequate medical intervention. We collected the serum samples from the KD patients with CAL (n = 32) and those without CAL (n = 31), followed by a global screening with isobaric tagging for relative and absolute quantification (iTRAQ) technology and specific validation with an enzyme-linked immunosorbent assay (ELISA). iTRAQ identified 846 proteins in total in the serum samples, and four candidate proteins related to CAL were selected for ELISA validation as follows: Protein S100-A4 (S100A4), Catalase (CAT), Folate receptor gamma (FOLR3), and Galectin 10 (CLC). ELISA validation showed that the S100A4 level was significantly higher in KD patients with CAL than in those without CAL (225.2 ± 209.5 vs. 143.3 ± 83 pg/mL, p < 0.05). In addition, KD patients with CAL had a significantly lower CAT level than those without CAL (1.6 ± 1.5 vs. 2.7 ± 2.3 ng/mL, p < 0.05). Next, we found that S100A4 treatment on human coronary artery endothelial cells (HCAECs) reduced the abundance of cell junction proteins, which promoted the migration of HCAECs. Further assays also demonstrated that S100A4 treatment enhanced the permeability of the endothelial layer. These results concluded that S100A4 treatment resulted in an incompact endothelial layer and made HCAECs more susceptible to in vitro neutrophil infiltration. In addition, both upregulated S100A4 and downregulated CAT increased the risk of CAL in KD. Further in vitro study implied that S100A4 could be a potential therapeutic target for CAL in KD.

Pharmacological Inhibition of S100A4 Attenuates Fibroblast Activation and Renal Fibrosis

The TGF-β/Smad3 signaling pathway is an important process in the pathogenesis of kidney fibrosis. However, the molecular mechanisms are not completely elucidated. The current study examined the functional role of S100A4 in regulating TGF-β/Smad3 signaling in fibroblast activation and kidney fibrosis development. S100A4 was upregulated in the kidney in a murine model of renal fibrosis induced by folic acid nephropathy. Further, S100A4 was predominant in the tubulointerstitial cells of the kidney. Pharmacological inhibition of S100A4 with niclosamide significantly attenuated fibroblast activation, decreased collagen content, and reduced extracellular matrix protein expression in folic acid nephropathy. Overexpression of S100A4 in cultured renal fibroblasts significantly facilitated TGF-β1-induced activation of fibroblasts by increasing the expression of α-SMA, collagen-1 and fibronectin. In contrast, S100A4 knockdown prevented TGF-β1-induced activation of fibroblast and transcriptional activity of Smad3. Mechanistically, S100A4 interacts with Smad3 to stabilize the Smad3/Smad4 complex and promotes their translocation to the nucleus. In conclusion, S100A4 facilitates TGF-β signaling via interaction with Smad3 and promotes kidney fibrosis development. Manipulating S100A4 may provide a beneficial therapeutic strategy for chronic kidney disease.

Aged Callus Skeletal Stem/Progenitor Cells Contain an Inflammatory Osteogenic Population With Increased IRF and NF-κB Pathways and Reduced Osteogenic Potential

Skeletal stem/progenitor cells (SSPCs) are critical for fracture repair by providing osteo-chondro precursors in the callus, which is impaired in aging. However, the molecular signatures of callus SSPCs during aging are not known. Herein, we performed single-cell RNA sequencing on 11,957 CD45-CD31-Ter119- SSPCs isolated from young and aged mouse calluses. Combining unsupervised clustering, putative makers, and DEGs/pathway analyses, major SSPC clusters were annotated as osteogenic, proliferating, and adipogenic populations. The proliferating cluster had a differentiating potential into osteogenic and adipogenic lineages by trajectory analysis. The osteoblastic/adipogenic/proliferating potential of individual clusters was further evidenced by elevated expression of genes related to osteoblasts, adipocytes, or proliferation. The osteogenic cluster was sub-clustered into house-keeping and inflammatory osteogenic populations that were decreased and increased in aged callus, respectively. The majority of master regulators for the inflammatory osteogenic population belong to IRF and NF-κB families, which was confirmed by immunostaining, RT-qPCR, and Western blot analysis. Furthermore, cells in the inflammatory osteogenic sub-cluster had reduced osteoblast differentiation capacity. In conclusion, we identified 3 major clusters in callus SSPCs, confirming their heterogeneity and, importantly, increased IRF/NF-κB-mediated inflammatory osteogenic population with decreased osteogenic potential in aged cells.

Shotgun Proteomics for the Identification and Profiling of the Tear Proteome of Keratoconus Patients

Purpose

The qualitative approach followed in this study aims to obtain an extensive view of the keratoconus (KC) tear proteome, which could highlight proteins previously undetected and enlarge our knowledge of the disease's pathophysiology.

Methods

Twenty-five patients diagnosed with KC and 25 control subjects were studied in a prospective, cross-sectional study. KC screening examinations, including clinical and tomographic examinations, were performed on all participants. Tear samples were collected using Schirmer strips and analyzed by liquid chromatography-tandem mass spectrometry in a data-dependent workflow. A spectral count was used as a semiquantification tool. The tear proteomes of both groups were identified and profiled, and the functional interactions and biological characterization of differential proteins were analyzed using in silico tools.

Results

We identified a total of 232 proteins, of whom 133 were expressed in both groups’ samples; 41 were observed only in control samples and 58 were identified just in tears of patients with KC. A semiquantitative analysis showed the dysregulation of 17 proteins in the KC samples. An in silico analysis linked proteins only expressed in KC samples to oxidative stress, skin development, and apoptosis. The dysregulation of proteins involved in iron transport, inflammation, oxidative stress, and protease inhibition was observed in the semiquantitative results.

Conclusions

A shotgun analysis showed that the tear proteome of patients with KC differed from controls by more than one-third of the total proteins identified, highlighting the relationship of the proteins only expressed in KC tears with processes of cell death, oxidative damage, and inflammation. The underexpression of proteins involved in iron pathways might support the iron imbalance as a contributing factor to cellular damage and death in KC disease.

Transcriptomic Profiling of Gene Expression Associated with Granulosa Cell Tumor Development in a Mouse Model

Ovarian granulosa cell tumors (GCTs) are rare sex cord-stromal tumors, accounting for ~5% ovarian tumors. The etiology of GCTs remains poorly defined. Genetically engineered mouse models are potentially valuable for understanding the pathogenesis of GCTs. Mice harboring constitutively active TGFβ signaling (TGFBR1-CA) develop ovarian GCTs that phenocopy several hormonal and molecular characteristics of human GCTs. To determine molecular alterations in the ovary upon TGFβ signaling activation, we performed transcriptomic profiling of gene expression associated with GCT development using ovaries from 1-month-old TGFBR1-CA mice and age-matched controls. RNA-sequencing and bioinformatics analysis coupled with the validation of select target genes revealed dysregulations of multiple cellular events and signaling molecules/pathways. The differentially expressed genes are enriched not only for known GCT-related pathways and tumorigenic events but also for signaling events potentially mediated by neuroactive ligand-receptor interaction, relaxin signaling, insulin signaling, and complements in TGFBR1-CA ovaries. Additionally, a comparative analysis of our data in mice with genes dysregulated in human GCTs or granulosa cells overexpressing a mutant FOXL2, the genetic hallmark of adult GCTs, identified some common genes altered in both conditions. In summary, this study has revealed the molecular signature of ovarian GCTs in a mouse model that harbors the constitutive activation of TGFBR1. The findings may be further exploited to understand the pathogenesis of a class of poorly defined ovarian tumors.

The Roles of Long-Term Hyperhomocysteinemia and Micronutrient Supplementation in the AppNL–G–F Model of Alzheimer’s Disease

A causal contribution of hyperhomocysteinemia to cognitive decline and Alzheimer’s disease (AD), as well as potential prevention or mitigation of the pathology by dietary intervention, have frequently been subjects of controversy. In the present in vivo study, we attempted to further elucidate the impact of elevated homocysteine (HCys) and homocysteic acid (HCA) levels, induced by dietary B-vitamin deficiency, and micronutrient supplementation on AD-like pathology, which was simulated using the amyloid-based App^NL–G–F knock-in mouse model. For this purpose, cognitive assessment was complemented by analyses of ex vivo parameters in whole blood, serum, CSF, and brain tissues from the mice. Furthermore, neurotoxicity of HCys and HCA was assessed in a separate in vitro assay. In confirmation of our previous study, older App^NL–G–F mice also exhibited subtle phenotypic impairment and extensive cerebral amyloidosis, whereas dietary manipulations did not result in significant effects. As revealed by proximity extension assay-based proteome analysis, the App^NL–G–F genotype led to an upregulation of AD-characteristic neuronal markers. Hyperhomocysteinemia, in contrast, indicated mainly vascular effects. Overall, since there was an absence of a distinct phenotype despite both a significant amyloid-β burden and serum HCys elevation, the results in this study did not corroborate the pathological role of amyloid-β according to the “amyloid hypothesis,” nor of hyperhomocysteinemia on cognitive performance. Nevertheless, this study aided in further characterizing the App^NL–G–F model and in elucidating the role of HCys in diverse biological processes. The idea of AD prevention with the investigated micronutrients, however, was not supported, at least in this mouse model of the disease.

Dysfunction of S100A4+ effector memory CD8+ T cells aggravates asthma

Progressive loss of effector functions, especially IFN-γ secreting capability, in effector memory CD8⁺ T (CD8⁺ T_EM ) cells plays a crucial role in asthma worsening. However, the mechanisms of CD8⁺ T_EM cell dysfunction remain elusive. Here, we report that S100A4 drives CD8⁺ T_EM cell dysfunction, impairing their protective memory response and promoting asthma worsening in an ovalbumin (OVA)-induced asthmatic murine model. We find that CD8⁺ T_EM cells contain two subsets based on S100A4 expression. S100A4⁺ subsets exhibit dysfunctional effector phenotypes with increased proliferative capability, whereas S100A4^- subsets retain effector function but are more inclined to apoptosis, giving rise a dysfunctional CD8⁺ T_EM cell pool. Mechanistically, S100A4 upregulation of mitochondrial metabolism results in a decrease of acetyl-CoA levels, which impair the transcription of effector genes, especially ifn-γ, facilitating cell survival, tolerance and memory potential. Our findings thus reveal general insights into how S100A4 CD8⁺ T_EM cells reprogram into dysfunctional and less protective phenotypes to aggravate asthma. This article is protected by copyright. All rights reserved.

Proteomic profiling based classification of CLL provides prognostication for modern therapy and identifies novel therapeutic targets

Protein expression for 384 total and post-translationally modified proteins was assessed in 871 CLL and MSBL patients and was integrated with clinical data to identify strategies for improving diagnostics and therapy, making this the largest CLL proteomics study to date. Proteomics identified six recurrent signatures that were highly prognostic of survival and time to first or second treatment at three levels: individual proteins, when grouped into 40 functionally related groups (PFGs), and systemically in signatures (SGs). A novel SG characterized by hairy cell leukemia like proteomics but poor therapy response was discovered. SG membership superseded other prognostic factors (Rai Staging, IGHV Status) and were prognostic for response to modern (BTK inhibition) and older CLL therapies. SGs and PFGs membership provided novel drug targets and defined optimal candidates for Watch and Wait vs. early intervention. Collectively proteomics demonstrates promise for improving classification, therapeutic strategy selection, and identifying novel therapeutic targets.

Human Amnion Epithelial Cells: A Potential Cell Source for Pulp Regeneration?

The aim of this study was to analyze the suitability of pluripotent stem cells derived from the amnion (hAECs) as a potential cell source for revitalization in vitro. hAECs were isolated from human placentas, and dental pulp stem cells (hDPSCs) and dentin matrix proteins (eDMPs) were obtained from human teeth. Both hAECs and hDPSCs were cultured with 10% FBS, eDMPs and an osteogenic differentiation medium (StemPro). Viability was assessed by MTT and cell adherence to dentin was evaluated by scanning electron microscopy. Furthermore, the expression of mineralization-, odontogenic differentiation- and epithelial–mesenchymal transition-associated genes was analyzed by quantitative real-time PCR, and mineralization was evaluated through Alizarin Red staining. The viability of hAECs was significantly lower compared with hDPSCs in all groups and at all time points. Both hAECs and hDPSCs adhered to dentin and were homogeneously distributed. The regulation of odontoblast differentiation- and mineralization-associated genes showed the lack of transition of hAECs into an odontoblastic phenotype; however, genes associated with epithelial–mesenchymal transition were significantly upregulated in hAECs. hAECs showed small amounts of calcium deposition after osteogenic differentiation with StemPro. Pluripotent hAECs adhere on dentin and possess the capacity to mineralize. However, they presented an unfavorable proliferation behavior and failed to undergo odontoblastic transition.

An Integrated Proteomics and Metabolomics Strategy for the Mechanism of Calcium Oxalate Crystal-Induced Kidney Injury

Renal fibrosis is the pathological repair reaction of the kidney to chronic injury, which is an important process of chronic kidney disease (CKD) progressing to end-stage renal failure. Nephrolithiasis is one of the most common renal diseases, with waist and abdomen pain, hematuria, urinary tract infection, and other clinical symptoms, which can increase the risk of renal fibrosis. Oxalate crystal-induced kidney injury is an early stage of nephrolithiasis; it is of great significance to explore the mechanism for the prevention and treatment of nephrolithiasis. A rodent model of calcium oxalate (CaOx) crystal-induced kidney injury was used in the present study, and a network analysis method combining proteomics and metabolomics was conducted to reveal the mechanism of crystal kidney injury and to provide potential targets for the intervention of nephrolithiasis. Using the metabolomics method based on the UHPLC-Q/TOF-MS platform and the iTRAQ quantitative proteomics method, we screened a total of 244 metabolites and 886 proteins from the kidney tissues that had significant changes in the Crystal group compared with that in the Control group. Then, the ingenuity pathway analysis (IPA) was applied to construct a protein-to-metabolic regulatory network by correlating and integrating differential metabolites and proteins. The results showed that CaOx crystals could induce inflammatory reactions and oxidative stress through Akt, ERK1/2, and P38 MAPK pathways and affect amino acid metabolism and fatty acid β-oxidation to result in kidney injury, thus providing an important direction for the early prevention and treatment of nephrolithiasis.

Cancer-associated fibroblasts and their role in tumor progression

The stromal elements of a malignant tumor can promote cancer progression and metastasis. The structure of the tumor stroma includes connective tissue elements, blood vessels, nerves, and extracellular matrix (ECM). Some of the cellular elements of the tumor stroma are cancer-associated fibroblasts (CAFs). The origin and function of CAFs have been actively studied over the past thirty years. CAFs produce collagen, the main scaffold protein of the extracellular matrix. Collagen in the tumor stroma stimulates fibrosis, enhances the rigidity of tumor tissue, and disrupts the transmission of proliferation and differentiation signaling pathways. CAFs control tumor angiogenesis, cell motility, tumor immunogenic properties, and the development of resistance to chemo- and immunotherapy. As a result of metabolic adaptation of rapidly growing tumor tissue to the nutrients and oxygen deprivation, the main type of energy production in cells changes from oxidative phosphorylation to anaerobic glycolysis. These changes lead to sequential molecular alterations, including the induction of specified transcriptional factors that result in the CAFs activation. The molecular phenotype of activated CAFs is similar to fibroblasts activated during inflammation. In activated CAFs, alpha-smooth muscle actin (α-SMA) is synthetized de novo and various proteases and fibronectin are produced. Since CAFs are found in all types of carcinomas, these cells are potential targets for the development of new approaches for anticancer therapy. Some CAFs originate from resident fibroblasts of the organs invaded by the tumor, while others originate from epithelial tumor cells, which are undergoing an epithelial-mesenchymal transition (EMT). To date, many molecular and metabolic inducers of the EMT have been discovered including the transforming growth factor-beta (TGF-β), hypoxia, and inflammation. This review classifies modern concepts of molecular markers of CAFs, their functional features, and discusses the stages of epithelial-mesenchymal transition, and the potential of CAFs as a target for antitumor therapy.

The prognostic value of S100A calcium binding protein family members in predicting severe forms of COVID-19

Background

Excessive inflammation has been implicated in the immunopathogenesis of coronavirus disease 2019 (COVID-19). In the current study, the involvement of S100 calcium binding protein S100A4, S100A9, and S100A10 in the inflammatory settings of COVID-19 patients were evaluated.

Methods

Peripheral blood samples were obtained from 65 COVID-19 subjects and 50 healthy controls. From the blood samples, RNA was extracted and cDNA was synthesized, and then the mRNA expression levels of S100A4, S100A9, and S100A10 were measured by Real-time PCR.

Results

The mRNA expression of S100A4 (fold change [FC] = 1.45, P = 0.0011), S100A9 (FC = 1.47, P = 0.0013), and S100A10 (FC = 1.35, P = 0.0053) was significantly upregulated in COVID-19 patients than controls. The mRNA expression of S100A4 (FC = 1.43, P = 0.0071), (FC = 1.66, P = 0.0001), and S100A10 (FC = 1.63, P = 0.0003) was significantly upregulated in the severe COVID-19 subjects than mild-to-moderate subjects. There was a significant positive correlation between mRNA expression of S100A4 (ρ = 0.49, P = 0.030), S100A9 (ρ = 0.55, P = 0.009), and S100A10 (ρ = 0.39, P = 0.040) and d-dimer in the COVID-19 patients. The AUC for S100A4, S100A9, and S100A10 mRNAs were 0.79 (95% CI 0.66–0.92, P = 0.004), 0.80 (95% CI 0.67–0.93, P = 0.002), and 0.71 (95% CI 0.56–0.85, P = 0.010), respectively.

Conclusions

S100A4, S100A9, and S100A10 play a role in the inflammatory conditions in COVID-19 patients and have potential in prognosis of severe form of COVID-19. Targeting these modules, hopefully, might confer a therapeutic tool in preventing sever symptoms in the COVID-19 patients.

Single-cell analysis of human glioma and immune cells identifies S100A4 as an immunotherapy target

A major rate-limiting step in developing more effective immunotherapies for GBM is our inadequate understanding of the cellular complexity and the molecular heterogeneity of immune infiltrates in gliomas. Here, we report an integrated analysis of 201,986 human glioma, immune, and other stromal cells at the single cell level. In doing so, we discover extensive spatial and molecular heterogeneity in immune infiltrates. We identify molecular signatures for nine distinct myeloid cell subtypes, of which five are independent prognostic indicators of glioma patient survival. Furthermore, we identify S100A4 as a regulator of immune suppressive T and myeloid cells in GBM and demonstrate that deleting S100a4 in non-cancer cells is sufficient to reprogram the immune landscape and significantly improve survival. This study provides insights into spatial, molecular, and functional heterogeneity of glioma and glioma-associated immune cells and demonstrates the utility of this dataset for discovering therapeutic targets for this poorly immunogenic cancer.

Arctiin Inhibits Cervical Cancer Cell Migration and Invasion through Suppression of S100A4 Expression via PI3K/Akt Pathway

Arctiin, a lignan glycoside, is isolated from Arctium lappa L. The anticancer effects of arctiin have been demonstrated in several studies. However, no research has been conducted on the anti-migration effect of arctiin in cervical cancer cells. The present study examined the effects of arctiin on cervical cancer cells and investigated the possible molecular mechanism. We demonstrated that arctiin exhibited low cytotoxicity and significantly inhibited cell migration and invasion in human cervical cancer cells. The S100A4 protein expression and mRNA levels were significantly reduced in HeLa and SiHa cells with arctiin treatment. Furthermore, silencing S100A4 by using small interfering RNA reduced cell migration, while overexpression of S100A4 mitigated the migration inhibition imposed by arctiin in cervical cancer cells. Western blotting revealed that arctiin significantly reduced phosphoinositide 3-kinase (PI3K) and phosphorylation of Akt in cervical cancer cells. Moreover, selective Akt induction by an Akt activator, SC-79, reverted cervical cancer cell migration and S100A4 protein expression, which were reduced in response to arctiin. Taken together, these results suggest that arctiin inhibits cervical cancer cell migration and invasion through suppression of S100A4 and the PI3K/Akt pathway.

Transcriptional activation of S100A2 expression by HIF-1α via binding to the hypomethylated hypoxia response elements in HCC cells

Hepatocellular carcinoma (HCC) is one of the most prevalent and lethal cancers. Dysregulation of S100A2 has recently been found in many cancers including HCC. However, its regulatory mechanism in HCC remains poorly understood, especially in hypoxia. In this study, we found that S100A2 is upregulated and correlated with the clinicopathological features of HCC patients. Moreover, the elevated S100A2 showed worse overall survival. Functionally, S100A2 inhibition decreased the proliferation and migration of HepG2 cells. Interestingly, we found that HIF-1α directly binds to hypoxia response elements (HREs) of the S100A2 promoter region. S100A2 expression could be induced in an HIF-1α-dependent manner under hypoxia. Furthermore, S100A2 silencing significantly suppressed HCC cell proliferation and invasion under hypoxia. Mechanistically, pyrosequencing results showed that the hypomethylation status of CpG located in the HRE at the S100A2 promoter was correlated with S100A2 induction. Additionally, HIF-1α- mediated S100A2 activation was associated with TET2-related epigenetic inactivation. TET2 was enriched in the HRE of the S100A2 promoter in HepG2 cells. Finally, S100A2 methylation-related genes and pathways were analyzed. We found that the methylation of S100A2 is correlated with ANXA2, PPP1R15A, and FOS, which include in a hypoxia-related gene set from the GSEA database. Moreover, some EMT-related genes are associated with the methylation of S100A2 in HCC. Conclusively, our study thus uncovered a novel mechanism showing that hypoxia/HIF-1α signaling associated with DNA methylation enhances S100A2 expression in HCC. S100A2 may be useful as a target for facilitating novel diagnostic and therapeutic strategies in liver cancer.

Role of the S100 protein family in rheumatoid arthritis

Rheumatoid arthritis is a chronic systemic autoimmune disease characterized by synovial hyperplasia, inflammatory cell infiltration, and proliferation of inflammatory tissue (angiogranuloma). The destruction of joints and surrounding tissues eventually causes joint deformities and dysfunction or even loss. The S100 protein family is one of the biggest subtribes in the calcium-binding protein family and has more than 20 members. The overexpression of most S100 proteins in rheumatoid arthritis is closely related to its pathogenesis. This paper reviews the relationship between S100 proteins and the occurrence and development of rheumatoid arthritis. It will provide insights into the development of new clinical diagnostic markers and therapeutic targets for rheumatoid arthritis.

Neutralization of S100A4 induces stabilization of atherosclerotic plaques: role of smooth muscle cells

AIMS

During atherosclerosis, smooth muscle cells (SMCs) accumulate in the intima where they switch from a contractile to a synthetic phenotype. From porcine coronary artery, we isolated spindle-shaped (S) SMCs exhibiting features of the contractile phenotype and rhomboid (R) SMCs typical of the synthetic phenotype. S100A4 was identified as a marker of R-SMCs in vitro and intimal SMCs, in pig and man. S100A4 exhibits intra- and extracellular functions. In this study, we investigated the role of extracellular S100A4 in SMC phenotypic transition.

METHODS AND RESULTS

S-SMCs were treated with oligomeric recombinant S100A4 (oS100A4), which induced nuclear factor (NF)-κB activation. Treatment of S-SMCs with oS100A4 in combination with platelet-derived growth factor (PDGF)-BB induced a complete SMC transition towards a pro-inflammatory R-phenotype associated with NF-κB activation, through toll-like receptor-4. RNA sequencing of cells treated with oS100A4/PDGF-BB revealed a strong up-regulation of pro-inflammatory genes and enrichment of transcription factor binding sites essential for SMC phenotypic transition. In a mouse model of established atherosclerosis, neutralization of extracellular S100A4 decreased area of atherosclerotic lesions, necrotic core, and CD68 expression and increased α-smooth muscle actin and smooth muscle myosin heavy chain expression.

CONCLUSION

We suggest that the neutralization of extracellular S100A4 promotes the stabilization of atherosclerotic plaques. Extracellular S100A4 could be a new target to influence the evolution of atherosclerotic plaques.

S100A4 Is Critical for a Mouse Model of Allergic Asthma by Impacting Mast Cell Activation

Background

The calcium-binding protein S100A4 demonstrates important regulatory roles in many biological processes including tumorigenesis and inflammatory disorders such as allergy. However, the specific mechanism of the contribution of S100A4 to allergic diseases awaits further clarification.

Objective

To address the effect of S100A4 on the regulation of mast cell activation and its impact on allergy.

Methods

Bone marrow-derived cultured mast cells (BMMCs) were derived from wild-type (WT) or S100A4-/- mice for in vitro investigation. WT and S100A4-/- mice were induced to develop a passive cutaneous anaphylaxis (PCA) model, a passive systemic anaphylaxis (PSA) model, and an ovalbumin (OVA)-mediated mouse asthma model.

Results

Following OVA/alum-based sensitization and provocation, S100A4-/- mice demonstrated overall suppressed levels of serum anti-OVA IgE and IgG antibodies and proinflammatory cytokines in serum, bronchoalveolar lavage fluid (BALF), and lung exudates. S100A4-/- mice exhibited less severe asthma signs which included inflammatory cell infiltration in the lung tissue and BALF, and suppressed mast cell recruitment in the lungs. Reduced levels of antigen reencounter-induced splenocyte proliferation in vitro were recorded in splenocytes from OVA-sensitized and challenged mice that lacked S100A4-/-. Furthermore, deficiency in the S100A4 gene could dampen mast cell activation both in vitro and in vivo, evidenced by reduced β-hexosaminidase release and compromised PCA and PSA reaction. We also provided evidence supporting the expression of S100A4 by mast cells.

Conclusion

S100A4 is required for mast cell functional activation, and S100A4 may participate in the regulation of allergic responses at least partly through regulating the activation of mast cells.

MiR-296-5p ameliorates deep venous thrombosis by inactivating S100A4

Deep venous thrombosis is one of the most common venous thromboembolic diseases and has a low cure rate and a high postoperative recurrence rate. Furthermore, emerging evidence indicates that microRNAs are involved in deep venous thrombosis. miR-296-5p is an important microRNA that plays a critical role in various cellular functions, and S100A4 is closely related to vascular function. miR-296-5p is downregulated in deep venous thrombosis patients, and its predicted target S100A4 is upregulated in deep venous thrombosis patients. Therefore, it was hypothesized that miR-296-5p may play a vital role in the development of deep venous thrombosis by targeting S100A4. An Ox-LDL-stimulated HUVEC and deep venous thrombosis mouse model was employed to detect the biological functions of miR-296-5p and S100A4. Dual luciferase reporter assays and pull-down assays were used to authenticate the interaction between miR-296-5p and S100A4. ELISA and Western blotting were employed to detect the protein levels of thrombosis-related factors and the endothelial-to-mesenchymal transition (EndMT)-related factors. The miR-296-5p levels were reduced, while the S100A4 levels were enhanced in deep venous thrombosis patients, and the miR-296-5p levels were negatively correlated with the S100A4 levels in deep venous thrombosis patients. miR-296-5p suppressed S100A4 expression by targeting the 3' UTR of S100A4. MiR-296-5p knockdown accelerated ox-LDL-induced HUVEC apoptosis, oxidative stress, thrombosis-related factor expression, and EndMT, while S100A4 knockdown antagonized these effects in ox-LDL-induced HUVECs. S100A4 knockdown reversed the effect induced by miR-296-5p knockdown. Moreover, the in vivo studies revealed that miR-296-5p knockdown in deep venous thrombosis mice exacerbated deep venous thrombosis formation, whereas S100A4 knockdown had the opposite effect. These results indicate that elevated miR-296-5p inhibits deep venous thrombosis formation by inhibiting S100A4 expression. Both miR-296-5p and S100A4 may be potential diagnostic markers and therapeutic targets for deep venous thrombosis.

Proteomics, Personalized Medicine and Cancer

As of 2020 the human genome and proteome are both at >90% completion based on high stringency analyses. This has been largely achieved by major technological advances over the last 20 years and has enlarged our understanding of human health and disease, including cancer, and is supporting the current trend towards personalized/precision medicine. This is due to improved screening, novel therapeutic approaches and an increased understanding of underlying cancer biology. However, cancer is a complex, heterogeneous disease modulated by genetic, molecular, cellular, tissue, population, environmental and socioeconomic factors, which evolve with time. In spite of recent advances in treatment that have resulted in improved patient outcomes, prognosis is still poor for many patients with certain cancers (e.g., mesothelioma, pancreatic and brain cancer) with a high death rate associated with late diagnosis. In this review we overview key hallmarks of cancer (e.g., autophagy, the role of redox signaling), current unmet clinical needs, the requirement for sensitive and specific biomarkers for early detection, surveillance, prognosis and drug monitoring, the role of the microbiome and the goals of personalized/precision medicine, discussing how emerging omics technologies can further inform on these areas. Exemplars from recent onco-proteogenomic-related publications will be given. Finally, we will address future perspectives, not only from the standpoint of perceived advances in treatment, but also from the hurdles that have to be overcome.

Active Akt signaling triggers CLL toward Richter transformation via overactivation of Notch1

Richter's transformation (RT) is an aggressive lymphoma that occurs upon progression from chronic lymphocytic leukemia (CLL). Transformation has been associated with genetic aberrations in the CLL phase involving TP53, CDKN2A, MYC, and NOTCH1; however, a significant proportion of RT cases lack CLL phase-associated events. Here, we report that high levels of AKT phosphorylation occur both in high-risk CLL patients harboring TP53 and NOTCH1 mutations as well as in patients with RT. Genetic overactivation of Akt in the murine Eµ-TCL1 CLL mouse model resulted in CLL transformation to RT with significantly reduced survival and an aggressive lymphoma phenotype. In the absence of recurrent mutations, we identified a profile of genomic aberrations intermediate between CLL and diffuse large B-cell lymphoma. Multiomics assessment by phosphoproteomic/proteomic and single-cell transcriptomic profiles of this Akt-induced murine RT revealed an S100 protein-defined subcluster of highly aggressive lymphoma cells that developed from CLL cells, through activation of Notch via Notch ligand expressed by T cells. Constitutively active Notch1 similarly induced RT of murine CLL. We identify Akt activation as an initiator of CLL transformation toward aggressive lymphoma by inducing Notch signaling between RT cells and microenvironmental T cells.

microRNAs and Corresponding Targets Involved in Metastasis of Colorectal Cancer in Preclinical In Vivo Models

The high death toll of colorectal cancer patients is due to metastatic disease which is difficult to treat. The liver is the preferred site of metastasis, followed by the lungs and peritoneum. In order to identify new targets and new modalities of intervention we surveyed the literature for microRNAs (miRs) which modulate metastasis of colorectal cancer in preclinical in vivo models. We identified 12 up-regulated and 19 down-regulated miRs corresponding to the latter criterium. The vast majority (n=16) of identified miRs are involved in modulation of epithelial-mesenchymal transition (EMT). Other categories of metastasis-related miRs exhibit tumor- and metastasis-suppressing functions, modulation of signaling pathways, transmembrane receptors and a class of miRs, which interfere with targets which do not fit into these categories. Finally, we discuss the principles of miR inhibition and reconstitution of function, prospective clinical evaluation of with miR-related agents in the context of clinical evaluation in metastasis relevant settings.

S100A4 Is Involved in Stimulatory Effects Elicited by the FGF2/FGFR1 Signaling Pathway in Triple-Negative Breast Cancer (TNBC) Cells

Triple-negative breast cancer (TNBC) is an aggressive breast tumor subtype characterized by poor clinical outcome. In recent years, numerous advancements have been made to better understand the biological landscape of TNBC, though appropriate targets still remain to be determined. In the present study, we have determined that the expression levels of FGF2 and S100A4 are higher in TNBC with respect to non-TNBC patients when analyzing “The Invasive Breast Cancer Cohort of The Cancer Genome Atlas” (TCGA) dataset. In addition, we have found that the gene expression of FGF2 is positively correlated with S100A4 in TNBC samples. Performing quantitative PCR, Western blot, CRISPR/Cas9 genome editing, promoter studies, immunofluorescence analysis, subcellular fractionation studies, and ChIP assays, we have also demonstrated that FGF2 induces in TNBC cells the upregulation and secretion of S100A4 via FGFR1, along with the ERK1/2–AKT–c-Rel transduction signaling. Using conditioned medium from TNBC cells stimulated with FGF2, we have also ascertained that the paracrine activation of the S100A4/RAGE pathway triggers angiogenic effects in vascular endothelial cells (HUVECs) and promotes the migration of cancer-associated fibroblasts (CAFs). Collectively, our data provide novel insights into the action of the FGF2/FGFR1 axis through S100A4 toward stimulatory effects elicited in TNBC cells.

Oxidative Stress and Inflammatory Markers in Abdominal Aortic Aneurysm

Abdominal aortic aneurysm (AAA) is increasing due to aging of the population and is a major cause of death among the elderly. Ultrasound screening programs are useful in early diagnosis, but aneurysm size is not always a good predictor of rupture. Our aim was to analyze the value of circulating molecules related to oxidative stress and inflammation as new biomarkers to assist the management of AAA. The markers were quantified by ELISA, and their expression in the aneurysmal wall was studied by real-time PCR and by immunostaining. Correlation analysis of the studied markers with aneurysm diameter and peak wall stress (PWS), obtained by finite element analysis, and multivariate regression analysis to assess potential confounding factors were performed. Our study shows an extensive inflammatory infiltration in the aneurysmal wall, mainly composed by T-cells, macrophages and B-cells and altered levels of reactive oxygen species (ROS), IgM, IgG, CD38, GDF15, S100A4 and CD36 in plasma and in the aneurysmal tissue of AAA patients compared with controls. Circulating levels of IgG, CD38 and GDF15 positively correlated with abdominal aortic diameter, and CD38 was correlated with PWS. Our data show that altered levels of IgG, CD38 and GDF15 have potential diagnostic value in the assessment of AAA.