MANF brakes TLR4 signaling by competitively binding S100A8 with S100A9 to regulate macrophage phenotypes in hepatic fibrosis

Inflammation molecular network alterations in a depressive-like primate model

At present, there are no definitive biomarkers for major depressive disorder (MDD). Previous studies prompted that neuroimmunoinflammation is involved in the pathogenesis of depression and its factors become potential diagnostic biomarkers. Non-human primates exhibit depression-like behavior similar to humans in chronically stressed environments. Therefore, in the present study, after completing Whole transcriptome sequencing of peripheral blood, neurology-related and inflammatory molecules in plasma and cerebrospinal fluid were measured by Olink proximity extension assay technology simultaneously in 4 natural depressive-like (DL) cynomolgus monkeys and 4 normal controls to screen potential biological markers. Further, postmortem brain tissues and peripheral blood RNA sequencing data from MDD patients available in the Gene Expression Omnibus (GEO) database were used for cross-species validation. Compared to control monkeys, depressive-like monkeys exhibited elevated levels of neurocan (NCAN). RNA sequencing revealed Toll-like receptor 4 (TLR4) and the interacting S100 calcium-binding protein A family as key molecules in the inflammatory gene network. GEO brain tissue data showed up-regulation of S100A8 and S100A9 in the anterior cingulate cortex of MDD patients. These findings suggest that depressive-like monkeys are in a state of chronic low-grade inflammation and identify NCAN and TLR4 inflammatory network molecules as potential biomarkers of MDD.

Oral colon-targeted delivery of recombinant human MANF for alleviation of ulcerative colitis

Midbrain astrocyte-derived neurotrophic factor (MANF) is a secreted protein induced by endoplasmic reticulum stress. Previous studies have indicated that intravenous administration of 1 mg/kg/day recombinant human MANF protein with His tag (His-MANF) for 3 days can ameliorate acute ulcerative colitis in mice. However, long-term intravenous therapy has many disadvantages. In this paper, His-MANF protein was successfully encapsulated into alginate and hyaluronic acid hybrid hydrogel microcapsules in one step using the gas shear method and then coated by Eudragit S100 to construct an oral colon-targeted delivery system (MSH@E). The MSH@E microcapsules exhibited controlled and sustained release behavior and colon-targeting properties. Both fluorescent imaging and immunohistochemistry staining results showed that His-MANF protein could accumulate in the colitis colon for a longer residence time after oral delivery. In vivo studies demonstrated that oral administration of MSH@E microcapsules could alleviate DSS-induced colitis in mice without systemic toxicity. Importantly, even if the oral His-MANF dose was half of the intravenous His-MANF dose, oral delivery was still much more effective than intravenous injection, suggesting the development of the oral colon-targeted delivery system (MSH@E) has great significance and makes a breakthrough from intravenous to oral administration for His-MANF treatment of ulcerative colitis (UC).

Transcriptomics of Various Diseases Reveals the Core Role of Immune System Pathways in Retinal Damage Repair and Nerve Regeneration

Retinal ganglion cells (RGCs) are the only neuronal bridges connecting retinal inputs to the brain's visual processing centers, enabling visual perception. The axon of RGCs forms the optic nerve, which transmits visual information to the visual cortex. Damage to RGCs and their axons results in irreversible visual impairment. Acute retinal damage is commonly induced by conditions such as optic nerve compression, glaucoma, and optic neuritis, for which effective clinical treatments are currently unavailable. Therefore, understanding the response of RGCs and their axons to injury is crucial for the development of potential treatments. This study utilizes multiple models including optic nerve crush (ONC), acute intraocular pressure (IOP) elevation, and local lipopolysaccharide (LPS) injection into the optic nerve to mimic eye diseases. Three days post-surgery, mice underwent retinal isolation followed by bulk-RNA sequencing to analyze differential gene expression among models. Using thresholds of |Log2 fold change (FC)|> 2 and p-value < 0.05, the significant gene expression changes observed in each model were as follows: ONC (upregulated, 456; downregulated, 84), IOP (upregulated, 1946; downregulated, 655), and LPS (upregulated, 219; downregulated, 94). Gene ontology (GO) analysis of the upregulated genes unexpectedly revealed that immune system pathways were the primary shared targets across all three models. In contrast, the downregulated genes exhibited model-specific enrichment: synaptic components and functions in IOP, neurogenesis and neuronal development in ONC, and inflammation and antioxidant in LPS. These findings were further confirmed by Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. This suggests that managing immune activation is essential for treating acute retinal injury, and therapeutic strategies should address model-specific targets as well. Notably, 39 genes intersected across the models, and the protein-protein interaction (PPI) network identified Ccl5 as a key hub gene, underscoring its critical role in the pathophysiology of all three diseases.

Paternal Obesity-Induced H3K27me3 Elevation Leads to MANF-Mediated Transgenerational Metabolic Dysfunction in Female Offspring

Paternal lifestyle and environmental exposures can alter epigenetic changes in sperm and play a critical role in the offspring's future health, yet the underlying mechanisms remain elusive. The present study established a model of paternal obesity and found that the increased levels of H3K27me3 in sperm persist into the 8-cell embryo stage, resulting in a transgenerational decrease of Manf, which causes endoplasmic reticulum stress and activates the GRP78-PERK-EIF2α-ATF4-CHOP axis. This consequently leads to impaired glucose metabolism and apoptosis in the liver of female offspring. Based on these findings, the F0 mice are treated with 3-deazaneplanocin A, an EZH2 inhibitor, which successfully prevented metabolic dysfunction in F0 mice of the high-fat diet (HFD) group. Meanwhile, intravenous injection of recombinant human MANF in F1 female offspring can successfully rescue the metabolic dysfunction in the HFD-F1 group. These results demonstrate that paternal obesity triggers transgenerational metabolic dysfunction through sperm H3K27me3-dependent epigenetic regulation. The present study also identifies the H3K27me3-MANF pathway as a potentially preventive and therapeutic strategy for diabetes, although further studies are needed to validate its clinical applicability.

Myeloid-derived MANF ameliorates ethanol-induced liver injury by enhancing microRNA-223 expression

BACKGROUND

Myeloid cells play a pivotal role in the pathogenesis of alcoholic liver disease (ALD), yet the mechanisms regulating their function and specific contributions to ALD remain inadequately understood. This study aims to investigate the role of mesencephalic astrocyte-derived neurotrophic factor (MANF) in the development of ALD.

METHODS

Myeloid-specific Manf knockout mice and wild-type controls were fed an ethanol-based diet for 10 days, followed by a single ethanol binge. Hepatic MANF levels, along with the correlation between MANF and inflammatory factors in patients with alcoholic hepatitis, were analyzed using the GSE28619 dataset.

RESULTS

Our study demonstrated that myeloid MANF expression in the liver was upregulated following chronic-plus-binge ethanol exposure. Deletion of the Manf gene in myeloid cells, including neutrophils, exacerbated ethanol-induced liver injury, steatosis, neutrophil infiltration, and reactive oxygen species production. Mechanistic analysis revealed that MANF promotes neutrophil miR-223 expression, a key anti-inflammatory factor in these cells. MANF enhances miR-223 transcription by increasing the expression of the transcription factor PU.1 via p38 mitogen-activated protein kinase signaling. In addition, hepatic MANF levels were elevated in patients with alcoholic hepatitis and correlated with IL-6, IL-1β, and phagocytic oxidase (phox) p47phoxlevels.

CONCLUSION

Myeloid-derived MANF mitigates alcohol-induced liver injury by upregulating the neutrophilic p38-PU.1-miR-223 axis.

Mesencephalic Astrocyte-Derived Neurotrophic Factor (MANF) Restricts Inflammatory Progression through Limiting Macrophage Infiltration in DRG and Sciatic Nerve during Diabetic Peripheral Neuropathy

Diabetic peripheral neuropathy (DPN) is a prevalent complication affecting over half of individuals with diabetes. This study investigates the role of mesencephalic Astrocyte-derived neurotrophic factor (MANF) in DPN progression and its potential as a therapeutic target. Using a streptozotocin (STZ)-induced diabetic mouse model, we analyzed MANF expression in the dorsal root ganglia (DRG) and sciatic nerve and assessed the effects of recombinant human MANF (rhMANF) administration on DPN symptoms. Our findings show significant upregulation of MANF protein levels in the DRG of diabetic mice, along with an increased presence of MANF-expressing macrophages in both the DRG and sciatic nerve. Intravenous administration of rhMANF from Day 7 to Day 21 post-STZ injection yielded multiple beneficial outcomes. Notably, rhMANF treatment alleviated mechanical hypoalgesia, as measured by the paw mechanical withdrawal threshold (PMWT), and enhanced sciatic nerve conduction, improving motor nerve conduction velocity (MNCV). Additionally, it increased intradermal nerve density, indicated by more PGP9.5-positive nerve fibers in the plantar skin of treated diabetic mice. These improvements were associated with reduced macrophage infiltration in the DRG and sciatic nerve, marked by fewer CD68 and Iba-1 positive cells, and inhibition of inflammatory signaling pathways. Specifically, rhMANF treatment decreased NF-κB p65 phosphorylation and suppressed p38 MAPK phosphorylation, indicating reduced inflammation. In summary, our research underscores MANF's potential as a novel therapeutic target for DPN, particularly due to its anti-inflammatory properties. Further exploration of MANF could lead to the development of more effective treatments for this debilitating aspect of diabetes.

GAMG alleviates liver fibrosis through inducing ferroptosis in inflammatory macrophages via the IRF1/SLC7A11 signaling pathway

The activation of inflammatory macrophages plays a pivotal role in the development of liver fibrosis (LF). Ferroptosis contributes to the clearance of inflammatory macrophages and the release of profibrotic factors. Glycyrrhetic Acid 3-O-Mono-β-d-glucuronide (GAMG) is a natural compound, the potential role of which on LF remains uncertain. In this study, GAMG treatment significantly reduced hepatocyte steatosis, fibroplasia, inflammatory cell infiltration, and collagen fiber deposition in LF mice. In addition, GAMG remarkably decreased the content of collagen protein and improved liver function indicators. Single-cell RNA sequencing revealed that GAMG significantly affected the changes of macrophage subsets in LF, and Funrich analysis identified IRF1 as a key transcription factor regulating the macrophage genome. IRF1 was significantly increased while ferroptosis related SLC7A11 was significantly down-regulated in GAMG treated inflammatory macrophages. Mass spectrometry metabolomics analysis showed that GAMG significantly affected metabolites associated with LF. In vivo and in vitro experiments further verified that GAMG induced ferroptosis of inflammatory macrophages through the IRF1/SLC7A11 axis, and ultimately alleviated LF. Therefore, GAMG induces ferroptosis of inflammatory macrophages by activating the IRF1/SLC7A11 axis, which provides a new strategy for the treatment of LF.

Tungsten-based polyoxometalate nanoclusters as ferroptosis inhibitors modulating S100A8/A9-mediated iron metabolism pathway for managing intracerebral haemorrhage

BACKGROUND

Intracerebral haemorrhage (ICH) is a devastating neurological disorder with high morbidity and mortality rates, largely owing to the lack of effective therapeutic strategies. Growing evidence has underscored the pivotal role of ferroptosis in intracerebral haemorrhage, and its contribution to neuronal death and exacerbation of brain injury, thus establishing it as a crucial target for therapeutic intervention. In recent years, polyoxometalate nanoclusters (NCs) have been applied in various neurodegenerative diseases, demonstrating neuroprotective effects. However, their impact on brain iron content and neurological function following ICH has yet to be reported. Here, we explored the potential of tungsten-based polyoxometalate (W-POM) NCs as ferroptosis inhibitors targeting the iron metabolic pathway mediated by S100A8/A9 for the treatment of ICH.

RESULTS

We successfully synthesized ultra-small reduced W-POM NCs that can rapidly cross the blood-brain barrier and are cleared through the kidney. In vitro experiments demonstrated that W-POM NCs exhibit significant and stable ROS scavenging activity while effectively alleviating iron overload and associated neuronal damage. In vivo, W-POM NCs treatment restored iron metabolism homeostasis, suppressed neuroinflammation and oxidative stress, ultimately alleviating severe neurological damage and motor deficits in ICH mice. Proteomic combined with bioinformatic analyses identified two core genes, S100A8 and S100A9, most associated with W-POM NCs intervention in ICH. Further experiments confirmed that W-POM NCs act by modulating the toll-like receptor 4/hepcidin/ferroportin signaling pathway, thereby regulating iron metabolism and reducing secondary brain injury.

CONCLUSIONS

This study pioneers the application of polyoxometalates in intracerebral haemorrhage, offering a novel and promising therapeutic approach for the management of ferroptosis-related brain injuries.

Hepatic factor MANF drives hepatocytes reprogramming by detaining cytosolic CK19 in intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma (ICC) is characterized by poor prognosis and limited treatment. Hepatocytes have been considered as one of the origins of ICC, however, the underlying mechanisms remain unclear. Here, we found mesencephalic astrocyte-derived neurotrophic factor (MANF), a hepatoprotective factor, was exceptionally upregulated in human ICC tissues and experimental mouse ICC models induced by sleeping beauty transposon (SBT) or thioacetamide (TAA) challenge. We identified MANF as a biomarker for distinguishing the primary liver cancer and verified the oncogenic role of MANF in ICC using cell lines overexpressing/knocked down MANF and mice specifically knocked in/out MANF in hepatocytes. Lineage tracing revealed that MANF promoted mature hepatocyte transformation into ICC cells. Mechanistically, MANF interacted with CK19 at Ser35 to suppress CK19 membrane recruitment. Cytosolic CK19 bound to AR domain of Notch2 intracellular domain (NICD2) to stabilize NICD2 protein level and trigger Notch signaling, which contributed to hepatocyte transformation to ICC cells. We uncover a novel profile of MANF and the original mechanism, which shed light on ICC diagnosis and intervention.

METTL1 coordinates cutaneous squamous cell carcinoma progression via the m7G modification of the ATF4 mRNA

Methyltransferase-like 1 (METTL1)-mediated m7G modification is a common occurrence in various RNA species, including mRNAs, tRNAs, rRNAs, and miRNAs. Recent evidence suggests that this modification is linked to the development of several cancers, making it a promising target for cancer therapy. However, the specific role of m7G modification in cutaneous squamous cell carcinoma (cSCC) is not well understood. In this study, we observed conspicuously elevated levels of METTL1 in cSCC tumors and cell lines. Inhibiting METTL1 led to reduced survival, migration, invasion, and xenograft tumor growth in cSCC cells. Mechanistically, through a combination of RNA sequencing, m7G methylated immunoprecipitation (MeRIP)-qPCR, and mRNA stability assays, we discovered that METTL1 is responsible for the m7G modification of ATF4 mRNA, leading to increased expression of ATF4. Importantly, we demonstrated that this modification is dependent on the methyltransferase activity of METTL1. Additionally, we observed a positive association between ATF4 expression and METTL1 levels in cSCC tumors. Intriguingly, restoring ATF4 expression in cSCC cells not only promoted glycolysis but also reversed the anti-tumor effects of METTL1 knockdown. In conclusion, our results underscore the critical role of METTL1 and m7G modification in cSCC tumorigenesis, suggesting a promising target for future cSCC therapies.

MANF overexpression ameliorates oxidative stress-induced apoptosis of human nucleus pulposus cells by facilitating mitophagy through promoting MFN2 expression

Intervertebral disc degeneration (IDD) is a degenerative condition associated with impaired mitophagy. MANF has been shown to promote mitophagy in murine kidneys; however, its role in IDD remains unexplored. This study aimed to elucidate the mechanism by which MANF influences IDD development through the regulation of mitophagy. Human nucleus pulposus (NP) cells were exposed to tert-butyl hydroperoxide (TBHP) to establish an oxidative stress-induced cellular model. The expression levels of MANF in NP cells were quantified using quantitative real-time PCR (qPCR) and Western blotting. The impact of MANF on TBHP-induced NP cells was evaluated by assessing cell viability, apoptosis, and the levels of mitophagy-related proteins. The underlying mechanisms were further investigated using RNA-binding protein immunoprecipitation (RIP), dual-luciferase reporter assays, qPCR, and Western blotting. Results indicated that MANF expression was significantly downregulated in both IDD patients and TBHP-induced NP cells. Overexpression of MANF inhibited apoptosis, enhanced cell viability, and promoted mitophagy in TBHP-treated NP cells. MFN2 was identified as a downstream target of MANF, and MANF overexpression upregulated MFN2 expression in NP cells, whereas TBHP markedly suppressed MFN2 expression. Furthermore, knockdown of MFN2 partially reversed the effects of MANF overexpression on apoptosis, cell viability, and mitophagy in TBHP-treated NP cells. Collectively, these findings demonstrate that MANF overexpression enhances mitophagy by upregulating MFN2 expression, thereby mitigating oxidative stress-induced apoptosis in NP cells. These results provide novel insights into the pathogenesis of IDD.

S100A8 promotes tumor progression by inducing phenotypic polarization of microglia through the TLR4/IL-10 signaling pathway in glioma

Background

S100A8 is a member of the S100 protein family and plays a pivotal role in regulating inflammation and tumor progression. This study aimed to comprehensively assess the expression patterns and functional roles of S100A8 in glioma progression.

Methods

Glioma tissues were collected from 98 patients who underwent surgical treatment at Fudan University Shanghai Cancer Center. S100A8 expression in glioma tissues was analyzed using immunohistochemistry (IHC) to establish its correlation with clinicopathological features in patients. The expression and prognostic effect of S100A8 in glioma were analyzed using TCGA and CGGA public databases. Then, we investigated the role of S100A8 in glioma through a series of in vivo and in vitro experiments including Transwell, wound healing, CCK8, and intracranial tumor models. Subsequently, bioinformatics analysis, single-cell sequencing and coimmunoprecipitation (Co-IP) were used to explore the underlying mechanism.

Results

S100A8 was upregulated in gliomas compared to paracancerous tissues, and this phenotype was significantly correlated with poor prognosis. Subgroup analysis showed that S100A8 expression was higher in the high-grade glioma (HGG) group than that in the low-grade glioma (LGG) group. S100A8 overexpression in glioma cell lines promoted cell proliferation, migration and invasion, while silencing S100A8 reversed these effects. In vivo experiments showed that S100A8 knockdown can significantly reduce the tumor burden of glioma cells. Notably, S100A8 was observed to stimulate microglial M2 polarization by interacting with TLR4, which subsequently induced NF-κB signaling and IL-10 secretion within the tumor microenvironment.

Conclusions

S100A8 promotes tumor progression by inducing phenotypic polarization of microglia through the TLR4/IL-10 signaling pathway in glioma. It might represent a therapeutic target for further basic research or clinical management of glioma.

Unlocking the promise of MANF in diseases: Mechanistic insights and therapeutic potentials

Mesencephalic astrocyte-derived neurotrophic factor (MANF) is a ubiquitous neurotrophic factor that exhibits a variety of physiological functions and plays a critical role in the exploitation of therapeutic potential across a range of diseases, including cardiovascular disorders, nervous system diseases, metabolic imbalances, and cancers. In the context of cardiac diseases, MANF significantly promotes cardiomyocyte survival and improves cardiac functionality. Furthermore, MANF not only provides neuroprotection by shielding neurons from damage and promoting nerve regeneration in neurological disorders, but also involves in insulin resistance, lipid metabolism disturbances and fat-containing liver lesions. However, the oncogenic or tumor suppressive function of MANF in cancer remains unclear, requiring further investigation to elucidate its precise role in the process of cancer initiation and progression. This review aims to summarize the latest advancements in understanding the molecular pathways, intricate mechanisms, and therapeutic potential of MANF in the prevention and treatment of various diseases, emphasizing its multifaceted contributions to health and disease management.

Reprogramming tumor-associated macrophages and inhibiting tumor neovascularization by targeting MANF-HSF1-HSP70-1 pathway: An effective treatment for hepatocellular carcinoma

In advanced hepatocellular carcinoma (HCC) tissues, M2-like tumor-associated macrophages (TAMs) are in the majority and promotes HCC progression. Contrary to the pro-tumor effect of M2-like TAMs, M1-like TAMs account for a small proportion and have anti-tumor effects. Since TAMs can switch from one type to another, reprogramming TAMs may be an important treatment for HCC therapy. However, the mechanisms of phenotypic switch and reprogramming TAMs are still obscure. In this study, we analyzed differential genes in normal macrophages and TAMs, and found that loss of MANF in TAMs accompanied by high levels of downstream genes negatively regulated by MANF. MANF reprogrammed TAMs into M1 phenotype. Meanwhile, loss of MANF promoted HCC progression in HCC patients and mice HCC model, especially tumor neovascularization. Additionally, macrophages with MANF supplement suppressed HCC progression in mice, suggesting MANF supplement in macrophage was an effective treatment for HCC. Mechanistically, MANF enhanced the HSF1-HSP70-1 interaction, restricted HSF1 in the cytoplasm of macrophages, and decreased both mRNA and protein levels of HSP70-1, which in turn led to reprogramming TAMs, and suppressing neovascularization of HCC. Our study contributes to the exploration the mechanism of TAMs reprogramming, which may provide insights for future therapeutic exploitation of HCC neovascularization.

MANF serves as a novel hepatocyte factor to promote liver regeneration after 2/3 partial hepatectomy via doubly targeting Wnt/β-catenin signaling

Liver regeneration is an intricate pathophysiological process that has been a subject of great interest to the scientific community for many years. The capacity of liver regeneration is very critical for patients with liver diseases. Therefore, exploring the mechanisms of liver regeneration and finding good ways to improve it are very meaningful. Mesencephalic astrocyte-derived neurotrophic factor (MANF), a member of newly identified neurotrophic factors (NTFs) family, extensively expresses in the liver and has demonstrated cytoprotective effects during ER stress and inflammation. However, the role of MANF in liver regeneration remains unclear. Here, we used hepatocyte-specific MANF knockout (MANFHep-/-) mice to investigate the role of MANF in liver regeneration after 2/3 partial hepatectomy (PH). Our results showed that MANF expression was up-regulated in a time-dependent manner, and the peak level of mRNA and protein appeared at 24 h and 36 h after 2/3 PH, respectively. Notably, MANF knockout delayed hepatocyte proliferation, and the peak proliferation period was delayed by 24 h. Mechanistically, our in vitro results showed that MANF physically interacts with LRP5 and β-catenin, two essential components of Wnt/β-catenin pathway. Specifically, as a cofactor, MANF binds to the extracellular segment of LRP5 to activate Wnt/β-catenin signaling. On the other hand, MANF interacts with β-catenin to stabilize cytosolic β-catenin level and promote its nuclear translocation, which further enhance the Wnt/β-catenin signaling. We also found that MANF knockout does not affect the c-Met/β-catenin complex after 2/3 PH. In summary, our study confirms that MANF may serve as a novel hepatocyte factor that is closely linked to the activation of the Wnt/β-catenin pathway via intracellular and extracellular targets.

Rejuvenation of young blood on aging organs: Effects, circulating factors, and mechanisms

Aging causes degenerative changes in organs, leading to a decline in physical function. Over the past two decades, researchers have made significant progress in understanding the rejuvenating effects of young blood on aging organs, benefiting from heterochronic parabiosis models that connect the blood circulation of aged and young rodents. It has been discovered that young blood can partially rejuvenate organs in old animals by regulating important aging-related signaling pathways. Clinical trials have also shown the effectiveness of young blood in treating aging-related diseases. However, the limited availability of young blood poses a challenge to implementing anti-aging therapies on a large scale for older individuals. As a promising alternative, scientists have identified some specific anti-aging circulating factors in young blood that have been shown to promote organ regeneration, reduce inflammation, and alleviate fibrosis associated with aging in animal experiments. While previous reviews have focused primarily on the effects and mechanisms of circulating factors on aging, it is important to acknowledge that studying the rejuvenating effects and mechanisms of young blood has been a significant source of inspiration in this field, and it will continue to be in the future. In recent years, new findings have emerged, further expanding our knowledge in this area. This review aims to summarize the rejuvenating effects and mechanisms of young blood and circulating factors, discussing their similarities and connections, addressing discrepancies in previous studies, outlining future research directions, and highlighting the potential for clinical translation in anti-aging interventions.

Alarmin S100A8 imparts chemoresistance of esophageal cancer by reprogramming cancer-associated fibroblasts

Chemotherapy remains the first-line treatment for advanced esophageal cancer. However, durable benefits are achieved by only a limited subset of individuals due to the elusive chemoresistance. Here, we utilize patient-derived xenografts (PDXs) from esophageal squamous-cell carcinoma to investigate chemoresistance mechanisms in preclinical settings. We observe that activated cancer-associated fibroblasts (CAFs) are enriched in the tumor microenvironment of PDXs resistant to chemotherapy. Mechanistically, we reveal that cancer-cell-derived S100A8 triggers the intracellular RhoA-ROCK-MLC2-MRTF-A pathway by binding to the CD147 receptor of CAFs, inducing CAF polarization and leading to chemoresistance. Therapeutically, we demonstrate that blocking the S100A8-CD147 pathway can improve chemotherapy efficiency. Prognostically, we found the S100A8 levels in peripheral blood can serve as an indicator of chemotherapy responsiveness. Collectively, our study offers a comprehensive understanding of the molecular mechanisms underlying chemoresistance in esophageal cancer and highlights the potential value of S100A8 in the clinical management of esophageal cancer.

Mesencephalic astrocyte-derived neurotrophic factor inhibits cervical cancer progression via regulating macrophage phenotype

BACKGROUND

Cervical cancer is a common gynecologic malignant tumor, but the critical factors affecting cervical cancer progression are still not well demonstrated. Mesencephalic astrocyte-derived neurotrophic factor (MANF) has been widely recognized as an anti-inflammatory factor to regulate macrophage polarization. In this study, the effect and mechanism of MANF on cervical cancer were preliminarily explored.

METHODS AND RESULTS

Kaplan-Meier curve was used to show the overall survival time of the involved cervical cancer patients with high and low MANF expression in cervical cancer tissues. MANF was highly expressed in peritumoral tissues of cervical carcinoma by using immunohistochemistry and western blot. MANF mRNA level was detected by using qRT-PCR. Dual-labeled immunofluorescence showed MANF was mainly expressed in macrophages of cervical peritumoral tissues. Moreover, MANF-silenced macrophages promoted HeLa and SiHa cells survival, migration, invasion and EMT via NF-κB signaling activation. The results of tumor formation in nude mice indicated MANF-silenced macrophages promoted cervical tumor formation in vivo.

CONCLUSION

Our study reveals an inhibitory role of MANF in cervical cancer progression, indicating MANF as a new and valuable therapeutic target for cervical cancer treatment.

Mesencephalic astrocyte-derived neurotrophic factor ameliorates inflammatory response in polycystic ovary syndrome via inhibiting TLR4-NF-κB-NLRP3 pathway

Polycystic ovary syndrome (PCOS) is a common reproductive endocrine disorder in women of reproductive age, which often leads to female infertility. Chronic inflammation is a significant factor in the development of PCOS. Our study aimed to explore the impact of mesencephalic astrocyte-derived neurotrophic factor (MANF), a scientifically validated anti-inflammatory factor, on 99 diagnosed PCOS patients. We also investigated its effects on PCOS mice induced with dehydroepiandrosterone (DHEA) and KGN cells induced with dihydrotestosterone (DHT). Our findings revealed a decrease in serum MANF levels in PCOS patients, which were negatively associated with serum tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) levels. The administration of recombinant human MANF (rhMANF) in PCOS mice demonstrated a decrease in pro-inflammatory cytokines and monocytes/macrophages in both peripheral blood and ovarian tissues. Furthermore, the inclusion of rhMANF notably ameliorated DHEA-induced ovarian dysfunction and fibrosis by negatively regulating the toll-like receptor 4 (TLR4)-nuclear factor kappa B (NF-κB)-NLR family, pyrin domain containing protein 3 (NLRP3) pathway. Additionally, in vitro experiments showed that the up-regulation of MANF offset DHT-induced inhibition of viability and apoptosis in KGN cells. Collectively, this study highlights the anti-inflammatory properties of MANF in PCOS and suggests its potential as a therapeutic approach for the management of PCOS.

CSF1R inhibition reprograms tumor-associated macrophages to potentiate anti-PD-1 therapy efficacy against colorectal cancer

PD-1 blockade therapy has made great breakthroughs in treatment of multiple solid tumors. However, patients with microsatellite-stable (MSS) colorectal cancer (CRC) respond poorly to anti-PD-1 immunotherapy. Although CRC patients with microstatellite instability (MSI) or microsatellite instability-high (MSI-H) can benefit from PD-1 blockade therapy, there are still some problems such as tumor recurrence. Tumor-associated macrophages (TAMs), most abundant immune components in tumor microenvironment (TME), largely limit the therapeutic efficacy of anti-PD-1 against CRC. The CSF1/CSF1R pathway plays a key role in regulating macrophage polarization, and blocking CSF1R signaling transduction may be a potential strategy to effectively reprogram macrophages and remodel TME. Here, we found that increasing expression of CSF1R in macrophages predicted poor prognosis in CRC cohort. Furthermore, we discovered a novel potent CSF1R inhibitor, PXB17, which significantly reprogramed M2 macrophages to M1 phenotype. Mechanically, PXB17 significantly blocked activation of PI3K/AKT/mTORC1 signaling, resulting in inhibition of cholesterol biosynthesis. Results from 3D co-culture system suggested that PXB17-repolarized macrophages could induce infiltration of CD8+ T lymphocytes in tumors and improve the immunosuppressive microenvironment. In vivo, PXB17 significantly halted CRC growth, with a stronger effect than PLX3397. In particular, PXB17 potently enhanced therapeutic activity of PD-1 mAb in CT-26 (MSS) model and prevented tumor recurrence in MC-38 (MSI-H) model by promoting formation of long-term memory immunity. Our study opens a new avenue for CSF1R in tumor innate and adaptive anti-tumor immunomodulatory activity and suggests that PXB17 is a promising immunotherapy molecule for enhancing the efficacy of PD-1 mAb or reducing tumor recurrence of CRC.

Hepatocytes-derived Prdx1 regulates macrophage phenotypes via TLR4 activation in acute liver injury

Acute liver injury (ALI) is a significant causative factor for multiple hepatic diseases. The excessive inflammatory response triggers proinflammatory immune cells recruitment, infiltration and differentiation, further contributing to inflammatory injuries in liver. As a proinflammatory factor, circulating Peroxiredoxin 1 (Prdx1) is elevated in ALI patients and mice. In this study, through carbon tetrachloride (CCl4) and cecal puncture and ligation (CLP)-induced liver injury mice model, we found hepatocytes-derived Prdx1 expression was increased in ALI. After AAV8-Prdx1-mediated Prdx1 knockdown, CCl4 and CLP-induced ALI was alleviated, along with the reduced proinflammatory cytokines, suppressed myeloid cells recruitment, decreased proportions of hepatic macrophages and neutrophils, restrained proinflammatory macrophage differentiation and infiltration. Mechanistically, hepatocyte-derived Prdx1 regulated macrophages through paracrine activation of the TLR4 signal. Our data support the immune and inflammatory regulatory role of Prdx1 in ALI pathological process to suggest its potential therapeutic application and clinical value.