Roles of chitinase 3-like 1 in the development of cancer, neurodegenerative diseases, and inflammatory diseases

Cryopreservation of human teeth using vitrification method with cryoprotectant cocktails and N-acetylcysteine for banking and clinical applications

Preserving freshly-extracted healthy human teeth offers an optional resource for potential tooth transplantation and cell therapy. This study aimed to assess the impact of vitrification, utilizing a blend of cryoprotectant agents and N-acetylcysteine (NAC), on the cryopreservation of periodontal ligament tissues, and investigate the underlying mechanisms of NAC on the tooth cryopreservation. Periodontal ligament cells were isolated from freshly-extracted healthy human permanent teeth, and cell sheets of PDLCs were fabricated. The samples including cell sheets, freshly-extracted human and rat teeth were cryopreserved with or without NAC for three months. The viability, ROS level, gene expressions and microstructure of PDLCs within cell sheets were assessed. The expression of SOD-2, Caspase3, LC3A/B and Catalase were evaluated through western blotting. Histological assessments of cryopreserved cell sheets and teeth were conducted. PDLCs were isolated from cryopreserved teeth, and their immunophenotype and differentiation ability were evaluated. The data was analyzed using one-way analysis of variance. The vitrification method showed good performance in preserving the viability and differentiation potential of PDLCs. Cryopreservation supplemented with NAC improved the survival rate of PDLCs, enhanced osteogenic differentiation ability, upregulated the expression of SOD-2 and Catalase, and inhibited cell apoptosis. Additionally, mRNA sequencing analysis revealed a significant activation of the PI3K-AKT pathway following cryopreservation via vitrification. Adding a PI3K-AKT activator improved the survival rates of PDLCs post-cryopreservation. The vitrification strategy combining various CPAs and NAC proved to be feasible for tooth cryopreservation. Targeting the PI3K-AKT pathway may improve the efficacy of tooth cryopreservation.

SPP1+ TAM Regulates the Metastatic Colonization of CXCR4+ Metastasis-Associated Tumor Cells by Remodeling the Lymph Node Microenvironment

Lymph node metastasis, the initial step in distant metastasis, represents a primary contributor to mortality in patients diagnosed with oral squamous cell carcinoma (OSCC). However, the underlying mechanisms of lymph node metastasis in OSCC remain incompletely understood. Here, the transcriptomes of 56 383 single cells derived from paired tissues of six OSCC patients are analyzed. This study founds that CXCR4+ epithelial cells, identified as highly malignant disseminated tumor cells (DTCs), exhibited a propensity for lymph node metastasis. Importantly, a distinct subset of tumor-associated macrophages (TAMs) characterized by exclusive expression of phosphoprotein 1 (SPP1) is discovered. These TAMs may remodel the metastatic lymph node microenvironment by potentially activating fibroblasts and promoting T cell exhaustion through SPP1-CD44 and CD155-CD226 ligand-receptor interactions, thereby facilitating colonization and proliferation of disseminated tumor cells. The research advanced the mechanistic understanding of metastatic tumor microenvironment (TME) and provided a foundation for the development of personalized treatments for OSCC patients with metastasis.

Tracking neuroinflammatory biomarkers in Alzheimer's disease: a strategy for individualized therapeutic approaches?

BACKGROUND

Recent trials of anti-amyloid-β (Aβ) monoclonal antibodies, including lecanemab and donanemab, in early Alzheimer disease (AD) showed that these drugs have limited clinical benefits and their use comes with a significant risk of serious adverse events. Thus, it seems crucial to explore complementary therapeutic approaches. Genome-wide association studies identified robust associations between AD and several AD risk genes related to immune response, including but not restricted to CD33 and TREM2. Here, we critically reviewed the current knowledge on candidate neuroinflammatory biomarkers and their role in characterizing the pathophysiology of AD.

MAIN BODY

Neuroinflammation is recognized to be a crucial and contributing component of AD pathogenesis. The fact that neuroinflammation is most likely present from earliest pre-stages of AD and co-occurs with the deposition of Aβ reinforces the need to precisely define the sequence and nature of neuroinflammatory events. Numerous clinical trials involving anti-inflammatory drugs previously yielded unfavorable outcomes in early and mild-to-moderate AD. Although the reasons behind these failures remain unclear, these may include the time and the target selected for intervention. Indeed, in our review, we observed a stage-dependent neuroinflammatory process in the AD brain. While the initial activation of glial cells counteracts early brain Aβ deposition, the downregulation in the functional state of microglia occurs at more advanced disease stages. To address this issue, personalized neuroinflammatory modulation therapy is required. The emergence of reliable blood-based neuroinflammatory biomarkers, particularly glial fibrillary acidic protein, a marker of reactive astrocytes, may facilitate the classification of AD patients based on the ATI(N) biomarker framework. This expands upon the traditional classification of Aβ ("A"), tau ("T"), and neurodegeneration ("N"), by incorporating a novel inflammatory component ("I").

CONCLUSIONS

The present review outlines the current knowledge on potential neuroinflammatory biomarkers and, importantly, emphasizes the role of longitudinal analyses, which are needed to accurately monitor the dynamics of cerebral inflammation. Such a precise information on time and place will be required before anti-inflammatory therapeutic interventions can be considered for clinical evaluation. We propose that an effective anti-neuroinflammatory therapy should specifically target microglia and astrocytes, while considering the individual ATI(N) status of patients.

Chitinase-3-like protein 1, matrix metalloproteinase-9, and monocyte chemoattractant protein-1 as potential biomarkers and treatment targets of adenomyosis

OBJECTIVE

This study aimed to investigate the levels of chitinase-3-like protein-1 (CHI3L1), matrix metalloproteinase-9 (MMP-9), and monocyte chemoattractant protein-1 (MCP-1) in adenomyosis, as compared to normal myometrial tissue. These biomarkers may be useful for determining potential treatment targets.

METHODS

This was a correlative, analytical, and observational study with a cross-sectional design. Participants with a diagnosis of moderate-to-severe adenomyosis, as determined through transvaginal ultrasonography and histological examination, and who underwent laparotomy or laparoscopic surgery for the treatment of adenomyosis, were enrolled in the study. Unlike other studies that recruited healthy women as controls, our study used adenomyotic and healthy nonadenomyotic myometria obtained from the same individual. The levels of CHI3L1, MMP-9, and MCP-1 in the biopsy samples were determined using enzyme-linked immunoassay kits, according to the manufacturer's protocol.

RESULTS

A highly significant increase in the levels of CHI3L1, MMP-9, and MCP-1 was found in adenomyotic tissues compared to non-adenomyotic tissues (P<0.001). A significant positive correlation was found between CHI3L1 and MMP-9 levels (r=0.463; P=0.008), CHI3L1 and MCP-1 levels (r=0.594; P<0.001), and MCP-1 and MMP-9 levels (r=0.680; P<0.001) in adenomyotic tissues.

CONCLUSION

CHI3L1 may play a role in the pathogenesis of adenomyosis via the regulation of the MCP-1 and MMP-9 pathways. Therefore, these molecules may serve as biomarkers and potential therapeutic targets for adenomyosis.

Elevated Serum Levels of YKL-40, YKL-39, and SI-CLP in Patients with Treatment Failure to DMARDs in Patients with Rheumatoid Arthritis

Around 30-60% of patients with rheumatoid arthritis (RA) present treatment failure to conventional synthetic disease-modifying antirheumatic drugs (csDMARDs). Chitinase-like proteins (CLPs) (YKL-40, YKL-39, SI-CLP) might play a role, as they are associated with the inflammatory process. This study aimed to evaluate CLP utility as a biomarker in the treatment failure of csDMARDs. A case-control study included 175 RA patients classified into two groups based on therapeutic response according to DAS28-ESR: responders (DAS28 < 3.2); non-responders (DAS28 ≥ 3.2). CLP serum levels were determined by ELISA. Multivariable logistic regression and receiver operating characteristic (ROC) curves were used to evaluate CLPs' utility as biomarkers of treatment failure. Non-responders presented higher levels of YKL-40, YKL-39, and SI-CLP compared with responders (all: p < 0.001). YKL-40 correlated positively with YKL-39 (rho = 0.39, p < 0.001) and SI-CLP (rho = 0.23, p = 0.011) and YKL-39 with SI-CLP (rho = 0.34, p < 0.001). The addition of CLPs to the regression models improves diagnostic accuracy (AUC 0.918) compared to models including only clinical classical variables (AUC 0.806) p < 0.001. Non-responders were positive for all CLPs in 35.86%. Conclusions: CLPs could be considered as a useful biomarker to assess treatment failure, due to their association with clinical variables and improvement to the performance of regression models.

α-Chitosan and β-Oligochitosan Mixtures-Based Formula for In Vitro Assessment of Melanocyte Cells Response

Chitosan is a natural polymer with numerous biomedical applications. The cellular activity of chitosan has been studied in various types of cancer, including melanoma, and indicates that these molecules can open new perspectives on antiproliferative action and anticancer therapy. This study analyzes how different chitosan conformations, such as α-chitosan (CH) or β-oligochitosan (CO), with various degrees of deacetylation (DDA) and molar mass (MM), both in different concentrations and in CH-CO mixtures, influence the cellular processes of SK-MEL-28 melanocytes, to estimate the reactivity of these cells to the applied treatments. The in vitro evaluation was carried out, aiming at the cellular metabolism (MTT assay), cellular morphology, and chitinase-like glycoprotein YKL-40 expression. The in vitro effect of the CH-CO mixture application on melanocytes is obvious at low concentrations of α-chitosan/β-oligochitosan (1:2 ratio), with the cell's response supporting the hypothesis that β-oligo-chitosan amplifies the effect. This oligochitosan mixture, favored by the β conformation and its small size, penetrates faster into the cells, being more reactive when interacting with some cellular components. Morphological effects expressed by the loss of cell adhesion and the depletion of YKL-40 synthesis are significant responses of melanocytes. β-oligochitosan (1.5 kDa) induces an extension of cytophysiological effects and limits the cell viability compared to α-chitosan (400-900 kDa). Statistical analysis using multivariate techniques showed differences between the CH samples and CH-CO mixtures.

Research advances in serum chitinase-3-like protein 1 in liver fibrosis

While liver fibrosis remains a serious, progressive, chronic liver disease, and factors causing damage persist, liver fibrosis may develop into cirrhosis and liver cancer. However, short-term liver fibrosis is reversible. Therefore, an early diagnosis of liver fibrosis in the reversible transition phase is important for effective treatment of liver diseases. Chitinase-3-like protein 1 (CHI3L1), an inflammatory response factor that participates in various biological processes and is abundant in liver tissue, holds promise as a potential biomarker for liver diseases. Here, we aimed to review research developments regarding serum CHI3L1 in relation to the pathophysiology and diagnosis of liver fibrosis of various etiologies, providing a reference for the diagnosis, treatment, and prognosis of liver diseases.

Host-defence caerin 1.1 and 1.9 peptides suppress glioblastoma U87 and U118 cell proliferation through the modulation of mitochondrial respiration and induce the downregulation of CHI3L1

Glioblastoma, the most aggressive form of brain cancer, poses a significant global health challenge with a considerable mortality rate. With the predicted increase in glioblastoma incidence, there is an urgent need for more effective treatment strategies. In this study, we explore the potential of caerin 1.1 and 1.9, host defence peptides derived from an Australian tree frog, in inhibiting glioblastoma U87 and U118 cell growth. Our findings demonstrate the inhibitory impact of caerin 1.1 and 1.9 on cell growth through CCK8 assays. Additionally, these peptides effectively curtail the migration of glioblastoma cells in a cell scratch assay, exhibiting varying inhibitory effects among different cell lines. Notably, the peptides hinder the G0/S phase replication in both U87 and U118 cells, pointing to their impact on the cell cycle. Furthermore, caerin 1.1 and 1.9 show the ability to enter the cytoplasm of glioblastoma cells, influencing the morphology of mitochondria. Proteomics experiments reveal intriguing insights, with a decrease in CHI3L1 expression and an increase in PZP and JUNB expression after peptide treatment. These proteins play roles in cell energy metabolism and inflammatory response, suggesting a multifaceted impact on glioblastoma cells. In conclusion, our study underscores the substantial anticancer potential of caerin 1.1 and 1.9 against glioblastoma cells. These findings propose the peptides as promising candidates for further exploration in the realm of glioblastoma management, offering new avenues for developing effective treatment strategies.

Astrocyte-derived CHI3L1 signaling impairs neurogenesis and cognition in the demyelinated hippocampus

Cognitive dysfunction is a feature in multiple sclerosis (MS), a chronic inflammatory demyelinating disorder. A notable aspect of MS brains is hippocampal demyelination, which is closely associated with cognitive decline. However, the mechanisms underlying this phenomenon remain unclear. Chitinase-3-like (CHI3L1), secreted by activated astrocytes, has been identified as a biomarker for MS progression. Our study investigates CHI3L1's function within the demyelinating hippocampus and demonstrates a correlation between CHI3L1 expression and cognitive impairment in patients with MS. Activated astrocytes release CHI3L1 in reaction to induced demyelination, which adversely affects the proliferation and differentiation of neural stem cells and impairs dendritic growth, complexity, and spine formation in neurons. Our findings indicate that the astrocytic deletion of CHI3L1 can mitigate neurogenic deficits and cognitive dysfunction. We showed that CHI3L1 interacts with CRTH2/receptor for advanced glycation end (RAGE) by attenuating β-catenin signaling. The reactivation of β-catenin signaling can revitalize neurogenesis, which holds promise for therapy of inflammatory demyelination.

Chemosensitizing effect of pentoxifylline in sensitive and multidrug-resistant non-small cell lung cancer cells

Aim: Multidrug resistance (MDR) is frequent in non-small cell lung cancer (NSCLC) patients, which can be due to its fibrotic stroma. This work explores the combination of pentoxifylline, an anti-fibrotic and chitinase 3-like-1 (CHI3L1) inhibitor drug, with conventional chemotherapy to improve NSCLC treatment. Methods: The effect of pentoxifylline in the expression levels of P-glycoprotein (P-gp), CHI3L1 and its main downstream proteins, as well as on cell death, cell cycle profile, and P-gp activity was studied in two pairs of sensitive and MDR counterpart NSCLC cell lines (NCI-H460/NCI-H460/R and A549/A549-CDR2). Association studies between CHI3L1 gene expression and NSCLC patients' survival were performed using The Cancer Genome Atlas (TCGA) analysis. The sensitizing effect of pentoxifylline to different drug regimens was evaluated in both sensitive and MDR NSCLC cell lines. The cytotoxicity of the drug combinations was assessed in MCF10A non-tumorigenic cells. Results: Pentoxifylline slightly decreased the expression levels of CHI3L1, β-catenin and signal transducer and activator of transcription 3 (STAT3), and caused a significant increase in the G1 phase of the cell cycle in both pairs of NSCLC cell lines. A significant increase in the % of cell death was observed in the sensitive NCI-H460 cell line. TCGA analysis revealed that high levels of CHI3L1 are associated with low overall survival (OS) in NSCLC patients treated with vinorelbine. Moreover, pentoxifylline sensitized both pairs of sensitive and MDR NSCLC cell lines to the different drug regimens, without causing significant toxicity to non-tumorigenic cells. Conclusion: This study suggests the possibility of combining pentoxifylline with chemotherapy to increase NSCLC therapeutic response, even in cases of MDR.

CD138 as a Specific CSF Biomarker of Multiple Sclerosis

BACKGROUND AND OBJECTIVES

The aim of this study was to identify novel biomarkers for multiple sclerosis (MS) diagnosis and prognosis, addressing the critical need for specific and prognostically valuable markers in the field.

METHODS

We conducted an extensive proteomic investigation, combining analysis of (1) CSF proteome from symptomatic controls, fast and slow converters after clinically isolated syndromes, and patients with relapsing-remitting MS (n = 10 per group) using label-free quantitative proteomics and (2) oligodendrocyte secretome changes under proinflammatory or proapoptotic conditions using stable isotope labeling by amino acids in cell culture. Proteins exhibiting differential abundance in both proteomic analyses were combined with other putative MS biomarkers, yielding a comprehensive list of 87 proteins that underwent quantification through parallel reaction monitoring (PRM) in a novel cohort, comprising symptomatic controls, inflammatory neurologic disease controls, and patients with MS at various disease stages (n = 10 per group). The 11 proteins that passed this qualification step were subjected to a new PRM assay within an expanded cohort comprising 158 patients with either MS at different disease stages or other inflammatory or noninflammatory neurologic disease controls.

RESULTS

This study unveiled a promising biomarker signature for MS, including previously established candidates, such as chitinase 3-like protein 1, chitinase 3-like protein 2, chitotriosidase, immunoglobulin kappa chain region C, neutrophil gelatinase-associated lipocalin, and CD27. In addition, we identified novel markers, namely cat eye syndrome critical region protein 1 (adenosine deaminase 2, a therapeutic target in multiple sclerosis) and syndecan-1, a proteoglycan, also known as plasma cell surface marker CD138 and acting as chitinase 3-like protein 1 receptor implicated in inflammation and cancer signaling. CD138 exhibited good diagnostic accuracy in distinguishing MS from inflammatory neurologic disorders (area under the curve [AUC] = 0.85, CI 0.75-0.95). CD138 immunostaining was also observed in the brains of patients with MS and cultured oligodendrocyte precursor cells but was absent in astrocytes.

DISCUSSION

These findings identify CD138 as a specific CSF biomarker for MS and suggest the selective activation of the chitinase 3-like protein 1/CD138 pathway within the oligodendrocyte lineage in MS. They offer promising prospects for improving MS diagnosis and prognosis by providing much-needed specificity and clinical utility.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that CD138 distinguishes multiple sclerosis from other inflammatory neurologic disorders with an AUC of 0.85 (95% CI 0.75-0.95).

Cognitive and inflammatory heterogeneity in severe mental illness: Translating findings from blood to brain

Recent findings link cognitive impairment and inflammatory-immune dysregulation in schizophrenia (SZ) and bipolar (BD) spectrum disorders. However, heterogeneity and translation between the periphery and central (blood-to-brain) mechanisms remains a challenge. Starting with a large SZ, BD and healthy control cohort (n = 1235), we aimed to i) identify candidate peripheral markers (n = 25) associated with cognitive domains (n = 9) and elucidate heterogenous immune-cognitive patterns, ii) evaluate the regulation of candidate markers using human induced pluripotent stem cell (iPSC)-derived astrocytes and neural progenitor cells (n = 10), and iii) evaluate candidate marker messenger RNA expression in leukocytes using microarray in available data from a subsample of the main cohort (n = 776), and in available RNA-sequencing deconvolution analysis of postmortem brain samples (n = 474) from the CommonMind Consortium (CMC). We identified transdiagnostic subgroups based on covariance between cognitive domains (measures of speed and verbal learning) and peripheral markers reflecting inflammatory response (CRP, sTNFR1, YKL-40), innate immune activation (MIF) and extracellular matrix remodelling (YKL-40, CatS). Of the candidate markers there was considerable variance in secretion of YKL-40 in iPSC-derived astrocytes and neural progenitor cells in SZ compared to HC. Further, we provide evidence of dysregulated RNA expression of genes encoding YKL-40 and related signalling pathways in a high neuroinflammatory subgroup in the postmortem brain samples. Our findings suggest a relationship between peripheral inflammatory-immune activity and cognitive impairment, and highlight YKL-40 as a potential marker of cognitive functioning in a subgroup of individuals with severe mental illness.

Chitinase 3-like 1 expression associated with lymphatic metastasis and prognosis in urothelial carcinoma of the bladder

Objectives

Lymphatic metastasis, an early stage of the metastasis process, is associated with adverse clinical outcomes in urothelial carcinoma of the bladder (UCB). However, the role of inflammation in triggering lymphatic metastasis remains unclear.

Methods

We employed an RNA-sequencing cohort (n = 50) from Sun Yat-Sen Memorial Hospital (SYMH) to identify the most highly upregulated inflammatory gene associated with lymphatic metastasis. Using immunohistochemistry and immunofluorescence analyses, we validated the association of the identified molecule with clinical features and prognosis in an independent UCB cohort (n = 244) from SYMH. We also analysed TCGA-BLCA cohort (n = 408) to identify its potential biological pathways and immune landscape.

Results

In our study, chitinase 3-like 1 (CHI3L1) emerged as a significantly overexpressed proinflammatory mediator in UCB tissues with lymphatic metastasis compared to those without lymphatic metastasis (81.1% vs. 47.8%, P < 0.001). Within UCB tissues, CHI3L1 was expressed in both stromal cells (52.8%) and tumor cells (7.3%). Moreover, CHI3L1+ stromal cells, but not tumor cells, exhibited independent prognostic significance for both overall survival (P < 0.001) and recurrence-free survival (P = 0.006). CHI3L1+ stromal cells were positively associated with D2-40+ lymphatic vessel density (P < 0.001) and the immunosuppressive PD-L1/PD-1/CD8 axis in UCB tissues (all P < 0.05). A bioinformatics analysis also identified a positive association between CHI3L1 expression and lymphangiogenesis or immunosuppression pathways.

Conclusion

Our study established a clear association between stromal CHI3L1 expression and lymphatic metastasis, suggesting that stromal CHI3L1 expression is a potential prognostic marker for bladder cancer patients.

Involvement of YKL-40-positive macrophages commonly identified in polymyositis and dermatomyositis in the pathogenesis of myositis: a retrospective study

YKL-40 is implicated in inflammation and tissue repair, but no reports have investigated its involvement in myositis in polymyositis (PM) and dermatomyositis (DM). Therefore, we aimed to investigate the relationship between YKL-40 and PM/DM. We retrospectively enrolled 35 patients diagnosed with PM/DM along with 26 healthy controls (HCs). Both PM and DM were diagnosed according to Bohan and Peter's criteria. Serum YKL-40 levels were measured, age-corrected to YKL-40 percentile values, and compared to HCs. Patients with myositis without interstitial lung disease were also enrolled and compared to HCs. Immunofluorescence staining was performed to identify YKL-40-positive inflammatory cells in muscle biopsy samples from two patients each with PM and DM. Age-corrected serum YKL-40 levels were significantly higher in patients with PM/DM compared to HCs with and without lung disease; however, these levels decreased significantly after treatment. Immunohistochemical analysis showed infiltration of YKL-40-positive inflammatory cells into the intramuscular sheath and perimuscular membrane. Immunofluorescence staining showed CD68 expression in YKL-40-positive inflammatory cells, suggesting that these cells were macrophages. To the best of our knowledge, this is the first study to demonstrate that YKL-40-positive macrophages are present in PM and DM, indicating that YKL-40 may be involved in PM/DM.

IL13Rα2 as a crucial receptor for Chi3l1 in osteoclast differentiation and bone resorption through the MAPK/AKT pathway

BACKGROUND

Previous research has revealed that the 18 glycoside hydrolase gene family (GH18) member Chitinase 3-like 1 (Chi3l1) can regulate osteoclast differentiation and bone resorption. However, its downstream receptors and molecular mechanisms during osteoclastogenesis have yet to be elucidated.

METHODS

Initially, we conducted a comprehensive investigation to evaluate the effects of recombinant Chi3l1 protein or Chi3l1 siRNA on osteoclast differentiation and the RANKL-induced MAPK/AKT signaling pathways. Moreover, we used immunofluorescence and immunoprecipitation assays to identify IL13Rα2 as the downstream receptor of Chi3l1. Subsequently, we investigated the impact of IL13Rα2 recombinant protein or IL13Rα2-siRNA on osteoclast differentiation and the associated signaling pathways. Finally, we performed in vivo experiments to examine the effect of recombinant IL13Rα2 protein in an LPS-induced mouse model of cranial osteolysis.

RESULTS

Our findings highlight that the administration of recombinant Chi3l1 protein increased the formation of osteoclasts and bolstered the expression of several osteoclast-specific genes (TRAP, NFATC1, CTR, CTSK, V-ATPase d2, and Dc-STAMP). Additionally, Chi3l1 significantly promoted the RANKL-induced MAPK (ERK/P38/JNK) and AKT pathway activation, whereas Chi3l1 silencing inhibited this process. Next, using immunofluorescence and co-immunoprecipitation assays, we identified IL13Rα2 as the binding partner of Chi3l1 during osteoclastogenesis. IL13Rα2 recombinant protein or IL13Rα2-siRNA also inhibited osteoclast differentiation, and IL13Rα2-siRNA attenuated the RANKL-induced activation of the MAPK (ERK/P38/JNK) and AKT pathways, similar to the effects observed upon silencing of Chi3l1. Moreover, the promoting effect of recombinant Chi3l1 protein on osteoclastogenesis and the activation of the MAPK and AKT pathways was reversed by IL13Rα2 siRNA. Finally, recombinant LI13Rα2 protein significantly attenuated the LPS-induced cranial osteolysis and the number of osteoclasts in vivo.

CONCLUSIONS

Our findings suggested that IL13Rα2 served as a crucial receptor for Chi3l1, enhancing RANKL-induced MAPK and AKT activation to promote osteoclast differentiation. These findings provide valuable insights into the molecular mechanisms of Chi3l1 in osteoclastogenesis, with potential therapeutic implications for osteoclast-related diseases. Video Abstract.

Analytical and Clinical Evaluation of a Chemiluminescent Immunoassay to Detect Serum Chitinase-3-like Protein 1 in HBV-Related Liver Diseases

Serum chitinase-3-like protein 1 (CHI3L1) is a diagnostic marker for liver diseases, such as hepatocellular carcinoma (HCC). Herein, we aimed to evaluate the analytical performance of a chemiluminescent immunoassay (CLIA) for the quantitative detection of CHI3L1 and its application in hepatitis B virus (HBV)-related liver diseases. The CLIA for CHI3L1 detection presented good analytical performance, with a linear range of 1.50-2000.00 ng/mL and a detection limit of 0.98 ng/mL. To evaluate its clinical application, serum CHI3L1 levels were detected in 82 patients with chronic hepatitis B (CHB) and in 21 healthy controls. The patients with CHB and HCC had higher CHI3L1 levels than the healthy controls and the patients with CHB without HCC. However, CHI3L1 levels did not change significantly with the increase in liver fibrosis stages. The area under the receiver operating characteristic curve for the diagnosis of HBV-related HCC was 0.808, representing a moderate diagnostic value. Correlation analysis revealed a significant association between CHI3L1 and alpha-fetoprotein (AFP) levels, the fibrosis-4 (FIB-4) index, and the aspartate aminotransferase-to-platelet ratio index (APRI). In conclusion, compared with currently reported methods for CHI3L1 detection, the CLIA has a high sensitivity, a wide linear range, and an acceptable accuracy, precision, and reference intervals, making it valuable in the diagnosis of HBV-related HCC.

The Peripheral Profile of the Chitinase 3-like-1 in Benign Multiple Sclerosis - A Single Centre's Experience

BACKGROUND

A limited subgroup of multiple sclerosis (MS) patients present with a longterm disease evolution characterized by a limited disease progression, known as benign MS (BMS). Chitinase 3-like-1 (CHI3L1) levels are sensitive to inflammatory processes and may play a role in the pathogenesis of MS. In this observational, cross-sectional study, we aimed to evaluate the implications of serum CHI3L1 and inflammatory cytokines in BMS patients treated with interferon β-1b for over a decade.

METHODS

We collected serum samples from 17 BMS patients and 17 healthy controls (HC) to measure serum CHI3L1 levels and a Th17 panel of inflammatory cytokines. Serum levels of CHI3L1 were analysed using the sandwich ELISA method and the Th17 panel was assessed using the multiplex XMap technology on a Flexmap 3D Analyzer.

RESULTS

Serum CHI3L1 levels did not differ significantly from HC. We identified a positive correlation between CHI3L1 levels and relapses during treatment.

CONCLUSION

Our findings suggest that there are no differences in serum CHI3L1 levels between BMS patients and HC. However, serum CHI3L1 levels are sensitive to clinical inflammatory activity and may be associated with relapses in BMS patients.

YKL-40 promotes proliferation and invasion of HTR-8/SVneo cells by activating akt/MMP9 signalling in placenta accreta spectrum disorders

YKL-40 is a secreted glycoprotein that can promote invasion, angiogenesis and inhibit apoptosis, and was highly expressed in a variety of tumours. In this paper, we investigated the impacts of YKL-40 on proliferation and invasion in HTR-8/SVneo cells during placenta accreta spectrum disorders (PAS) development. The levels of YKL-40 protein in late-pregnant placental tissue were detected using immunohistochemistry and Western blotting, and gene expression using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The proliferation, migration, invasion and apoptosis abilities of HTR-8/SVneo cells were detected by cell counting kit-8 (CCK-8), Transwell, scratch assay, and flow cytometry, respectively. Our current results showed that YKL-40 was significantly increased in the PAS group compared to the normal control group (P < 0.01). Biological function experiments showed that YKL-40 significantly promoted the proliferation, migration and invasion of HTR-8/SVneo cells, and inhibited cell apoptosis. Knockdown of YKL-40 inhibited the activation of Akt/MMP9 signalling in trophoblast cells. These data suggested that YKL-40 might be involved in the progression of PAS, which may be attributed to the regulation of Akt/MMP9 signalling pathway.

Frailty is related to serum inflammageing markers: results from the VITAL study

Frailty describes an age-associated state in individuals with an increased vulnerability and less resilience against adverse outcomes. To score frailty, studies have employed the questionnaires, such as the SF-36 and EQ-5D-3L, or the Frailty Index, a composite score based on deficit accumulation. Furthermore, ageing of the immune system is often accompanied by a state of low-grade inflammation (inflammageing). Here, we aimed to associate 29 circulating markers of inflammageing with frailty measures in a prospective cohort study to understand the mechanisms underlying ageing.Frailty measures and inflammageing markers were assessed in 317 participants aged 25-90. We determined four different measures of frailty: the Frailty Index based on 31 deficits, the EQ-5D-3L and two physical domains of the SF-36. Serum/plasma levels of inflammageing markers and CMV/EBV seropositivity were measured using different techniques: Quanterix, Luminex or ELISA.All four measures of frailty strongly correlated with age and BMI. Nineteen biomarkers correlated with age, some in a linear fashion (IL-6, YKL-40), some only in the oldest age brackets (CRP), and some increased at younger ages and then plateaued (CCL2, sIL-6R). After correcting for age, biomarkers, such as IL-6, CRP, IL-1RA, YKL-40 and elastase, were associated with frailty. When corrected for BMI, the number of associations reduced further.In conclusion, inflammageing markers, particularly markers reflecting innate immune activation, are related to frailty. These findings indicate that health decline and the accumulation of deficits with age is accompanied with a low-grade inflammation which can be detected by specific inflammatory markers.

Current trends and future perspectives of stroke management through integrating health care team and nanodrug delivery strategy

Stroke is accounted as the second-most mortality and adult disability factor in worldwide, while causes the bleeding promptly and lifetime consequences. The employed functional recovery after stroke is highly variable, allowing to deliver proper interventions to the right stroke patient at a specific time. Accordingly, the multidisciplinary nursing team, and the administrated drugs are major key-building-blocks to enhance stroke treatment efficiency. Regarding the healthcare team, adequate continuum of care have been declared as an integral part of the treatment process from the pre-hospital, in-hospital, to acute post-discharge phases. As a curative perspective, drugs administration is also vital in surviving at the early step and reducing the probability of disabilities in later. In this regard, nanotechnology-based medicinal strategy is exorbitantly burgeoning. In this review, we have highlighted the effectiveness of current clinical care considered by nursing teams to treat stroke. Also, the advancement of drugs through synthesis of miniaturized nanodrug formations relating stroke treatment is remarked. Finally, the remained challenges toward standardizing the healthcare team and minimizing the nanodrugs downsides are discussed. The findings ensure that future works on normalizing the healthcare nursing teams integrated with artificial intelligence technology, as well as advancing the operative nanodrugs can provide value-based stroke cares.

Chitinase 3-like 1 plays a pivotal role in airway response of RSV infection via regulating DC functional transition

BACKGROUND

Dendritic cells (DCs) contribute to immune imbalance and airway hyperresponsiveness (AHR) induced by respiratory syncytial virus (RSV). The aim of present study was to explore the mechanism of RSV regulating naive T cell differentiation through DCs.

METHODS

We generated a Lentivirus shRNA expression vector to knock down CHI3L1 in mouse lungs and bone marrow-derived dendritic cells (BMDCs). Then we investigated the effect of CHI3L1 knockdown on MAPK/ERK pathway, PI3K/AKT pathway, mature DCs represented by molecular markers, naive T cell differentiation and related cytokine expression in vitro and in vivo models of RSV.

RESULTS

RSV elevated CHI3L1 expression in lung DCs and BMDCs. Knockdown of CHI3L1 impeded RSV-induced activation of MAPK/ERK and PI3K/AKT signaling pathways, attenuated CD86 and OX40L expression in mature DCs, reduced the proportion of Th2 and Th17 cells, and increased the proportion of Treg cells. In addition, by blocking CHI3L1, RSV-infected mice shown relief of airway resistance, the downregulation of Th2/Th17 like cytokines IL-4, IL-13 and IL-17 levels, and the upregulation of IL-10.

CONCLUSION

Our data show that CHI3L1 promotes RSV induced immune imbalance and airway hyperresponsiveness by regulating the functional transformation of DCs.

CHI3L1 promotes myocardial fibrosis via regulating lncRNA TUG1/miR-495-3p/ETS1 axis

Abnormal levels of CHI3L1 and lnc TUG1 are often associated with myocardial fibrosis, and their specific expressions may be closely related to the process of myocardial fibrosis. In addition, CHI3L1 was found to significantly up-regulate the expression of lncTUG1. Therefore, this study further explored the major role of CHI3L1 in regulating the progression of myocardial fibrosis. Myocardial fibrosis in mice was established using an angiotensin (Ang II) model, and the degree of myocardial fibrosis was assessed by qPCR, western blot and pathological techniques. HL-1 cells with overexpression and silencing of CHI3L1 were constructed, and the cell migration ability was detected using the Transwell method. Biological information was used to predict the potential target miRNA of lnc TUG1, and the interaction between them was verified by dual luciferase reporter assay. Using functional rescue assay and the rAAV9 technique, CHI3L1 was verified to affect the fibrotic process of myocardial cells by regulating the lnc TUG1/miR-495-3p/ETS1 axis in vitro and in vivo. The myocardial fibrosis index in the model group was significantly upregulated, and expression of both CHI3L1 and lnc TUG1 was upregulated. Pathological results revealed fibrosis and collagen deposition in the myocardium. Overexpression of lnc TUG1 reversed the inhibitory effect of CHI3L1 silencing on myocardial fibrosis. Mechanistically, CH3L1 upregulates the expression of lnc TUG1, and lnc TUG1 weakens the inhibition of ETS1 through sponge absorption of miR-495-3p, promoting the process of myocardial fibrosis.

Plasma YKL-40 is associated with prognosis in patients with metastatic pancreatic cancer receiving immune checkpoint inhibitors in combination with radiotherapy

Background

YKL-40, also known as chitinase-3-like protein 1 (CHI3L1), is a secreted glycoprotein produced by various cell types including stromal, immune, and cancer cells. It contributes to cancer progression through tumor-promoting inflammation and has been shown to inhibit the cytotoxicity of T and NK lymphocytes. In vivo studies have demonstrated synergistic anti-cancer effects of blocking YKL-40 in combination with immune checkpoint inhibitors (ICIs). Biomarkers for the prediction of the response to ICIs are highly needed. We investigated the association between plasma YKL-40 and clinical benefit and survival in patients with metastatic pancreatic cancer (mPC) receiving ICIs and stereotactic body radiotherapy (SBRT).

Methods

Blood samples were collected from 84 patients with mPC who participated in the randomized phase II CheckPAC study, in which patients received nivolumab with or without ipilimumab combined with a single fraction of SBRT. Plasma YKL-40 was measured using a commercial ELISA kit.

Results

Elevated baseline plasma YKL-40 was an independent predictor of shorter overall survival (OS) (HR 2.19, 95% CI 1.21-3.95). A ≥ 40% decrease in plasma YKL-40 during treatment was associated with longer progression-free survival (p = 0.009) and OS (p = 0.0028). There was no correlation between plasma YKL-40 and the tumor burden marker CA19-9 at baseline or during treatment.

Conclusion

This study contributes new knowledge regarding YKL-40 as a predictor of clinical benefit from ICIs and radiotherapy. These exploratory results warrant further investigation of YKL-40 as a biomarker for patients treated with immunotherapies.

Clinical trial registration

Clinicaltrials.gov, identifier NCT02866383.

Chitinase-3-like 1-protein in CSF: a novel biomarker for progression in patients with multiple sclerosis

BACKGROUND

Chitinase -3-like 1-protein (CHI3L1) is a glycoside secreted by monocytes, microglia, and activated astrocytes. Its distribution in inflammatory lesions denotes its role in astrocytic response to modulate CNS inflammation. In multiple sclerosis (MS), CHI3L1 levels have been found to be influenced by disease severity, activity, and progression. We aimed to measure CSF level of CHI3L1 in patients with MS and correlate its level with disability measures for a possible role as a biomarker for disease progression.

METHODS

Fifty-two MS patients (30 relapsing-remitting MS and 22 progressive MS) and thirty-five age and sex-matched healthy controls were included. They all underwent full clinical assessment (including disability and cognitive scales), radiological assessment, and CSF level of CHI3L1.

RESULTS

Patients with MS had higher CSF level of CHI3L1 than controls. Patients with progressive forms had higher levels than relapsing forms. There were positive correlations between disease duration, number of attacks, total EDSS, and CSF level of CHI3L1. Patients who had higher level of CSF CHI3L1 showed worse performance in MMSE and BICAMS and more lesions in T2 MRI brain. A cut off value of 154 ng/mL was found between patients with RRMS and PMS patients.

CONCLUSION

CHI3L1 can be considered as a biomarker of disease progression. CHI3L1 level increases in progressive MS more than RRMS. Also, high CSF level of CHI3L1 was associated with more disability including motor, cognitive, and radiological aspects.

[YKL-40 Promotes the Expression of Inflammatory Factors in Type Ⅱ Alveolar Epithelial Cell Model of A549 Cell Line]

Objective

YKL-40, also known as chitinase-3-like-1 (CHI3L1), is a human cartilage glycoprotein-39, with its N-terminus consisting of tyrosine (Y), lysine (K), and leucine (L), hence the name YKL-40. In this study, we explored whether YKL-40 could promote the expression of inflammatory factors in type Ⅱ alveolar epithelial cells.

Methods

A549 cells were cultured in vitro with interleukin (IL)-1β (20 ng/mL), IL-6 (20 ng/mL), tumor necrosis factor-alpha (TNF-α) (20 ng/mL), and interferon-gamma (IFN-γ) (20 ng/mL). The expression of YKL-40 transcription was determined by RT-qPCR. A549 cells were cultured with IL-1β at 5, 10, and 20 ng/mL and the expression of YKL-40 protein was determined by Western blot. A549 cells were cultured with recombinant YKL-40 protein at 0, 100, 500, and 1 000 ng/mL and the expression levels of IL-6 and IL-8 were measured by RT-qPCR. Three pairs of small interfering RNAs targeting YKL-40 (si- YKL-40-1/2/3) and the negative control (NC) were designed and used to transfect A549 cells, respectively, and the expression of YKL-40 was determined by RT-qPCR and Western blot. si- YKL-40-3 was screened out for subsequent experiments. In A549 cells, si- YKL-40-3 and si-NC were transfected and, then, IL-1β (20 ng/mL) was added in for culturing. The expression of YKL-40, IL-6, and IL-8 was determined by RT-qPCR and the expression of multiple factors in the supernatant was measured with the QAH-INF-1 kit.

Results

RT-qPCR results showed that IL-1β could up-regulate YKL-40 protein transcription level compared with that of the control group and the difference was statistically significant ( P<0.01), but IL-6, TNF-α, and IFN-γ could not up-regulate YKL-40 protein transcription level. Western blot results showed that IL-1β (20 ng/mL) could significantly promote the expression of YKL-40 and, compared with that of the control group, the differences showed by groups treated with different concentrations of IL-1β were all statistical significant ( P<0.01). After adding human recombinant YKL-40 protein to A549 cells, the results showed that the expression of inflammatory factors IL-6 and IL-8 was significantly increased and the difference was statistically significant compared with that of the control group ( P<0.05). After the expression of YKL-40 was decreased by si- YKL-40-3 transfection, the expression of IL-6 ( P<0.05), IL-8 ( P<0.05), and other inflammatory factors was inhibited compared with that of the control group.

Conclusion

YKL-40 can promote the expression and secretion of IL-6, IL-8, and other acute inflammatory factors in A549 cell line, a type Ⅱ alveolar epithelial cell model, thus aggravating the inflammatory response. Targeted inhibition of YKL-40 expression may effectively inhibit inflammatory response.

Postoperative serum CHI3L1 level is associated with postoperative cognitive dysfunction in elderly patients after hip fracture surgery: A prospective observational study

Objectives

Postoperative cognitive dysfunction (POCD) is a common postoperative complication in older patients. Chitinase-3-like-1 protein (CHI3L1) is identified as a neuroinflammatory biomarker and impairs cognitive function. This study aimed to evaluate the association between serum levels of CHI3L1 and POCD and explore the levels of interleukin-6 (IL-6), IL-1β and C-reactive protein (CRP) in the elderly after total hip arthroplasty (THA).

Patients and methods

A total of 76 elderly patients undergoing THA were enrolled in the prospective observational study. Serum CHI3L1 levels were measured 1 day before and 1 day after surgery and other perioperative factors were also noted. The correlations between mediators of inflammation in the two groups were compared via Spearman correlation coefficients. The receiver operating characteristic (ROC) curves were implemented to analyze the predictive values of serum CHI3L1 and other inflammatory factors for POCD. And factors associated with POCD were analyzed by univariate and multivariate logistics.

Results

POCD was observed in 31.6% of patients 1 week after surgery. Postoperative serum CHI3L1 levels were higher in POCD patients than in non-POCD patients [1348.26(778.46-1889.77) VS 2322.86(1686.88-2517.35) ng/ml, P < 0.001]. Postoperative serum CHI3L1 level was positively correlated with postoperative IL-6 level (r = 0.284, P = 0.013). Compared with IL-6, IL-1β, and CRP, postoperative CHI3L1 level has the highest predictive value for POCD with the area under the curve (AUC) value of 0.779 according to the ROC curve. By the multivariate logistic regression analysis, elevated postoperative serum CHI3L1 level was found to be an independent risk factor for POCD 1 week after surgery (odds ratio = 1.204, 95% confidence interval = 1.087-1.332, P = 0.001).

Conclusion

Postoperative elevated serum CHI3L1 level was significantly associated with the incident of POCD, and positively correlated with postoperative IL-6 level in the elderly after THA. This biomarker may have potential utility for further elucidating the etiology of POCD.

Regulatory role of Chitinase 3-like 1 gene in papillary thyroid carcinoma proved by integration analyses of single-cell sequencing with cohort and experimental validations

Papillary thyroid carcinoma (PTC) is one of the most common thyroid carcinomas. The gross extrathyroidal extension and extensive metastases of PTC lead to high rates of recurrence and poor clinical outcomes. However, the mechanisms underlying PTC development are poorly understood. In this study, using single-cell RNA sequencing, the transcriptome profiles of two PTC patients were addressed, including PTC1 with low malignancy and good prognosis and PTC2 with high malignancy and poor prognosis. We found that epithelial subcluster Epi02 was the most associated with the malignant development of PTC cells, with which the fold change of Chitinase 3-like 1 (CHI3L1) is on the top of the differentially expressed genes between PTC1 and PTC2 (P < 0.001). However CHI3L1 is rarely investigated in PTC as far. We then studied its role in PTC with a series of experiments. Firstly, qRT-PCR analysis of 14 PTC patients showed that the expression of CHI3L1 was positively correlated with malignancy. In addition, overexpression or silencing of CHI3L1 in TPC-1 cells, a PTC cell line, cultured in vitro showed that the proliferation, invasion, and metastasis of the cells were promoted or alleviated by CHI3L1. Further, immunohistochemistry analysis of 110 PTC cases revealed a significant relationship between CHI3L1 protein expression and PTC progression, especially the T (P < 0.001), N (P < 0.001), M stages (P = 0.007) and gross ETE (P < 0.001). Together, our results prove that CHI3L1 is a positive regulator of malignant development of PTC, and it promotes proliferation, invasion, and metastasis of PTC cells. Our study improves understanding of the molecular mechanisms underlying the progression of PTC and provides new insights for the clinical diagnosis and treatment of PTC.

Polarization of Cancer-Associated Macrophages Maneuver Neoplastic Attributes of Pancreatic Ductal Adenocarcinoma

Mounting evidence links the phenomenon of enhanced recruitment of tumor-associated macrophages towards cancer bulks to neoplastic growth, invasion, metastasis, immune escape, matrix remodeling, and therapeutic resistance. In the context of cancer progression, naïve macrophages are polarized into M1 or M2 subtypes according to their differentiation status, gene signatures, and functional roles. While the former render proinflammatory and anticancer effects, the latter subpopulation elicits an opposite impact on pancreatic ductal adenocarcinoma. M2 macrophages have gained increasing attention as they are largely responsible for molding an immune-suppressive landscape. Through positive feedback circuits involving a paracrine manner, M2 macrophages can be amplified by and synergized with neighboring neoplastic cells, fibroblasts, endothelial cells, and non-cell autonomous constituents in the microenvironmental niche to promote an advanced disease state. This review delineates the molecular cues expanding M2 populations that subsequently convey notorious clinical outcomes. Future therapeutic regimens shall comprise protocols attempting to abolish environmental niches favoring M2 polarization; weaken cancer growth typically assisted by M2; promote the recruitment of tumoricidal CD8⁺ T lymphocytes and dendritic cells; and boost susceptibility towards gemcitabine as well as other chemotherapeutic agents.

Rapid and ultrasensitive detection of acute kidney injury biomarkers CH3L1 and L-FABP using surface-enhanced Raman spectroscopy

Chitinase 3-like 1 (CH3L1) and liver fatty acid binding protein (L-FABP) are promising biomarkers for the early diagnosis of acute kidney injury (AKI). Here, a highly sensitive method for the quantitative detection of CH3L1 and L-FABP by surface-enhanced Raman spectroscopy (SERS) based on graphene oxide/gold and silver core-shell nanoparticles (GO/Au@Ag NPs) was proposed. The results showed that such GO/Au@Ag substrate can achieve rapid sensing of CH3L1 and L-FABP with a wide response range (2 × 10^-1 to 2 × 10^-8 mg/mL and 1.2 × 10^-1 to 1.2 × 10^-8 mg/mL, respectively) and high sensitivity. The detection limits of CH3L1 and L-FABP were 1.21 × 10^-8 mg/mL and 0.62 × 10^-8 mg/mL, respectively. In addition, the simultaneous detection of the two biomarkers in serum was demonstrated, showing the feasibility of this method in the complex biological environment. The detection of CH3L1 and L-FABP will greatly improve the early diagnosis and intervention of AKI.

A randomized phase II study of full dose gemcitabine versus reduced dose gemcitabine and nab-paclitaxel in vulnerable patients with non-resectable pancreatic cancer (DPCG-01)

BACKGROUND

According to current evidence, the best treatment for fit patients with non-resectable pancreatic cancer (PC) is combination chemotherapy, whereas frail patients are recommended gemcitabine (Gem) monotherapy. Randomized controlled trials in colorectal cancer and a post-hoc analysis of gemcitabine and nab-paclitaxel (GemNab) in PC suggest, however, that reduced dose of combination chemotherapy may be feasible and more efficient compared to monotherapy in frail patients. The aim of this study is to investigate whether reduced dose GemNab is superior to full dose Gem in patients with resectable PC, who are not candidates for full dose combination chemotherapy in first line.

METHODS

The Danish Pancreas Cancer Group (DPCG)-01 trial is a national multicenter prospective randomized phase II trial. A total of 100 patients in ECOG performance status 0-2 with non-resectable PC, not candidate for full dose combination chemotherapy in first line, but eligible for full dose Gem, will be included. Patients are randomized 1:1 to either full dose Gem or GemNab in 80% of recommended dose. The primary endpoint is progression-free survival. Secondary endpoints are overall survival, overall response rate, quality of life, toxicity and rate of hospitalizations during treatment. The correlation between blood inflammatory markers, including YKL-40 and IL-6, circulating tumor DNA, and tissue biomarkers of resistance to chemotherapy and outcome will be explored. Finally, the study will include measures of frailty (G8, modified G8, and chair-stand-test) to assess whether scoring would enable a personalized allocation to different treatments or indicates a possibility for interventions.

DISCUSSION

Single-drug treatment with Gem has for frail patients with non-resectable PC been the main treatment option for more than thirty years, but the impact on outcome is modest. If improved results and sustained tolerability with reduced dose combination chemotherapy can be shown, this could change the future practice for this increasing group of patients.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT05841420. Secondary Identifying No: N-20210068. EudraCT No: 2021-005067-52.

PROTOCOL VERSION

1.5, 16-MAY-2023.

Chitinase-3 like-protein-1, matrix metalloproteinase -9 and positive intracranial arterial remodelling

Introduction

Positive intracranial arterial remodelling is a dilated lesion of the large intracranial vessels; however, its pathogenesis is currently unknown. Some studies have identified chitinase-3 like-protein-1 (YKL-40) and matrix metalloproteinase (MMP)-9 as circulating inflammatory factors involved in positive vascular remodelling. Herein, we aimed to investigate the relationship between changes in serum YKL-40 and MMP-9 levels and positive intracranial arterial remodelling in patients with cerebral small vessel disease (CSVD).

Methods

A total of 110 patients with CSVD were selected. Patients with brain arterial remodelling (BAR) scores &gt;1 times the standard deviation were defined as the positive intracranial artery remodelling group (n = 21 cases), and those with BAR scores ≤1 times the standard deviation were defined as the non-positive intracranial artery remodelling group (n = 89 cases). Serum YKL-40 and MMP-9 levels were measured using an enzyme-linked immunosorbent assay kit. Factors influencing positive intracranial artery remodelling using binary logistic regression analysis and predictive value of YKL-40 and MMP-9 for positive intracranial arterial remodelling in patients with CSVD were assessed by a subject receiver operating characteristic curve.

Results

Statistically significant differences in serum YKL-40 and MMP-9 levels were observed between the positive and non-positive remodelling groups (p &lt; 0.05). The integrated indicator (OR = 9.410, 95% CI: 3.156 ~ 28.054, P&lt;0.01) of YKL-40 and MMP-9 levels were independent risk factors for positive intracranial arterial remodelling. The integrated indicator (OR = 3.763, 95% CI: 1.884 ~ 7.517, p &lt; 0.01) of YKL-40 and MMP-9 were independent risk factors for positive arterial remodelling in posterior circulation, but were not significantly associated with positive arterial remodelling in anterior circulation (p &gt; 0.05). The area under the curve for YKL-40 and MMP-9 diagnostic positive remodelling was 0.778 (95% CI: 0.692–0.865, p &lt; 0.01) and 0.736 (95% CI: 0.636–0.837, p &lt; 0.01), respectively.

Discussion

Elevated serum YKL-40 and MMP-9 levels are independent risk factors for positive intracranial arterial remodelling in patients with CSVD and may predict the presence of positive intracranial arterial remodelling, providing new ideas for the mechanism of its occurrence and development and the direction of treatment.

Transient Changes in Serum CEA, CA19-9, CRP, YKL-40, and IL-6 during Adjuvant Chemotherapy and Survival of Patients with Colorectal Cancer

Serum carcinoembryonic antigen (CEA) is frequently monitored to detect colorectal cancer (CRC) recurrence after surgery. The clinical significance of transiently increased CEA during adjuvant chemotherapy is poorly understood. Serum CEA, CA19-9, CRP, YKL-40, and IL-6 were measured before, during, and after adjuvant 5-fluorouracil-based chemotherapy in the randomised LIPSYT study population. The biomarker kinetic patterns were classified into three groups: no increase, a transient increase (≥10% increase followed by a decrease), and a persistent increase during the adjuvant treatment, and the associations of these patterns with disease free-survival (DFS) and overall survival (OS) were investigated by using Cox regression analyses. The findings were validated in two single-centre cohorts that received modern adjuvant chemotherapy. A transient increase in CEA occurred in about a half of the patients during chemotherapy, in all the cohorts. The patients with a transient increase had a roughly similar DFS and OS to the patients with no increase, and a more favourable survival compared to the patients with a persistent increase. In the LIPSYT cohort, the hazard ratio was 0.21 for DFS (CI_95% 0.07-0.66) and 0.24 for OS (CI_95% 0.08-0.76). Transient increases in CA19-9 and YKL-40 tended to be associated with a favourable survival. A transient increase in CEA during adjuvant chemotherapy is associated with a favourable survival when compared with a persistent increase.

YKL-40 as a novel biomarker related to white matter damage and cognitive impairment in patients with cerebral small vessel disease

YKL-40 is a novel neuroinflammatory marker associated with white matter damage and cognitive dysfunction. 110 CSVD patients, including 54 with mild cognitive impairment (CSVD-MCI), 56 with no cognitive impairment (CSVD-NCI), and 40 healthy controls (HCs) underwent multimodal magnetic resonance examination, serum YKL-40 level detection and cognitive function assessment to investigate the association between YKL-40 and white matter damage and cognitive impairment in cerebral small vessel disease (CSVD) patients. White matter hyperintensities volume was calculated using the Wisconsin White Matter Hyperintensity Segmentation Toolbox (W2MHS) for white matter macrostructural damage evaluation. For white matter microstructural damage evaluation, fractional anisotropy (FA) and mean diffusivity (MD) indices of the region of interest were analyzed based on diffusion tensor imaging (DTI) images using the Tract-Based Spatial Statistics (TBSS) pipeline. The serum YKL-40 level of CSVD was significantly higher than those of HCs, and the CSVD-MCI was higher than in HCs and CSVD-NCI. Furthermore, serum YKL-40 provided high diagnostic accuracy for CSVD and CSVD-MCI. The macroscopic and microstructure of white matter in CSVD-NCI and CSVD-MCI patients indicated different degrees of damage. Disruption of white matter macroscopic and microstructure was significantly associated with YKL-40 levels and cognition deficits. Moreover, the white matter damage mediated the associations between the increased serum YKL-40 levels and cognitive impairment. Our findings demonstrated that YKL-40 might be a potential biomarker of white matter damage in CSVD, whereas white matter damage was associated with cognitive impairment. Serum YKL-40 measurement provides complementary information regarding the neural mechanism of CSVD and its associated cognitive impairment.

The Potential Roles of CHI3L1 in Failed Autologous Arteriovenous Fistula in End-Stage Renal Disease

Autologous arteriovenous fistula (AVF) is commonly placed for hemodialysis treatment. Recent studies show that increased baseline serum level of Chitinase-3-like protein 1 (CHI3L1) is independently associated with a higher risk of the early failure of forearm AVFs. However, the changes and mechanisms of CHI3LI in local vascular tissues of failed AVF have not be revealed. This study aims to conduct the expression and mechanism of CHI3L1 in vascular tissues from patients. Immunoreactivity of CHI3L1, matrix metalloproteinase 2 (MMP-2) and vascular endothelial growth factor-A (VEGF-A) were detected in vascular tissues collected from nine patients with AVF surgery. Due to the significant stenosis clinically, six of the nine patients received arteriovenous fistula reconstruction. The expression differences of CHI3L1 between the initial vascular tissues and failed AVF are significant (P < 0.05). Failed AVF due to stenosis shows intraluminal thrombus, collagen fiber rupture, fibrous connective tissue hyperplasia, tube wall thickening, neovascularization, scattered inflammatory cell infiltration in the tunica media as well as high CHI3L1 expression level, and the expression of MMP-2 (r = 0.9022, P = 0.0139) and VEGF-A (r = 0.8355, P = 0.0393) was positively correlated with CHI3L1. CHI3L1 expression in vascular tissues possibly plays an important role in AVF failure. MMP-2 and VEGF-A may participate in venous stenosis with CHI3L1.

Combination of WFDC2, CHI3L1, and KRT19 in Plasma Defines a Clinically Useful Molecular Phenotype Associated with Prognosis in Critically Ill COVID-19 Patients

BACKGROUND

COVID-19 is now a common disease, but its pathogenesis remains unknown. Blood circulating proteins reflect host defenses against COVID-19. We investigated whether evaluation of longitudinal blood proteomics for COVID-19 and merging with clinical information would allow elucidation of its pathogenesis and develop a useful clinical phenotype.

METHODS

To achieve the first goal (determining key proteins), we derived plasma proteins related to disease severity by using a first discovery cohort. We then assessed the association of the derived proteins with clinical outcome in a second discovery cohort. Finally, the candidates were validated by enzyme-linked immunosorbent assay in a validation cohort to determine key proteins. For the second goal (understanding the associations of the clinical phenotypes with 28-day mortality and clinical outcome), we assessed the associations between clinical phenotypes derived by latent cluster analysis with the key proteins and 28-day mortality and clinical outcome.

RESULTS

We identified four key proteins (WFDC2, GDF15, CHI3L1, and KRT19) involved in critical pathogenesis from the three different cohorts. These key proteins were related to the function of cell adhesion and not immune response. Considering the multicollinearity, three clinical phenotypes based on WFDC2, CHI3L1, and KRT19 were identified that were associated with mortality and clinical outcome.

CONCLUSION

The use of these easily measured key proteins offered new insight into the pathogenesis of COVID-19 and could be useful in a potential clinical application.

Serum YKL-40 Levels and White Matter Hyperintensities in Patients with Acute Ischemic Stroke

Background

White matter hyperintensity (WMH) is associated with risk of acute ischemic stroke (AIS) and poor outcomes after AIS. The purpose of this prospective study was to evaluate the association between serum YKL-40 levels and WMH burden in patients with AIS.

Methods

From February 2020 to March 2021, a total of 672 consecutive AIS patients with magnetic resonance imaging data were prospectively recruited form two centers. Serum YKL-40 levels were quantified using enzyme-linked immunosorbent assay. The burden of WMH was semiquantitatively measured by the Fazekas visual grading scale. According to severity of overall WMH, patients were dichotomized into none-mild WMH group (Fazekas score 0-2) or moderate-severe WMH group (Fazekas score 3-6). Besides, based on severity of periventricular WMH (PV-WMH) and deep WMH (D-WMH), patients were categorized as none-mild (Fazekas score 0-1) or moderate-severe (Fazekas score 2-3).

Results

Among the 672 patients, 335 (49.9%) participants were identified with moderate-severe overall WMH, 326 (48.5%) with moderate-severe PV-WMH and 262 (39.0%) with moderate-severe D-WMH. Compared with the first quartile of serum YKL-40, the adjusted odds ratio (OR) of the fourth quartile for moderate-severe PV-WMH was 2.473 (95% confidence interval [CI] 1.316-4.646; P=0.005). No significant association was observed between YKL-40 and overall WMH (OR 0.762; 95% CI 0.434-1.336; P=0.343) or D-WMH (OR 0.695; 95% CI 0.413-1.171; P=0.172).

Conclusion

Our results suggested that higher YKL-40 levels appeared to be associated with PV-WMH, but not with overall WMH or D-WMH in patients with AIS.

Early approaches of YKL-40 as a biomarker and therapeutic target for Parkinson's disease

Aim: To investigate whether the estimation of cerebrospinal fluid (CSF) and brain YKL-40 levels may be used as an efficient biomarker for Parkinson's disease (PD). Methods: Lipopolysaccharides (LPS) was injected into the right substantia nigra pars compacta (SNpc). Rats were divided into: control group, early LPS-induced PD group (14 days), and advanced LPS-induced PD group (28 days). YKL-40 and other related factors were detected in CSF and brain tissue. Results: Increased expression of YKL-40 was observed in brain tissue and CSF of PD-induced rats associated with triggered inflammatory cytokine release. Conclusion: The current study was limited to detecting YKL-40 and other inflammatory factors in brain and CSF. YKL-40 may be considered as an early biomarker and therapeutic target for PD.

Chitinase-Assisted Bioconversion of Chitinous Waste for Development of Value-Added Chito-Oligosaccharides Products

Chito-oligosaccharides (COSs) are the partially hydrolyzed products of chitin, which is abundant in the shells of crustaceans, the cuticles of insects, and the cell walls of fungi. These oligosaccharides have received immense interest in the last few decades due to their highly promising bioactivities, such as their anti-microbial, anti-tumor, and anti-inflammatory properties. Regarding environmental concerns, COSs are obtained by enzymatic hydrolysis by chitinase under milder conditions compared to the typical chemical degradation. This review provides updated information about research on new chitinase derived from various sources, including bacteria, fungi, plants, and animals, employed for the efficient production of COSs. The route to industrialization of these chitinases and COS products is also described.

Associations between saliva and plasma cytokines in cognitively normal, older adults

BACKGROUND

Inflammatory responses play key roles in the development and progression of many pathological conditions, including neurodegenerative diseases. Accurate quantification of inflammatory factors in saliva would be highly advantageous, given its convenience and non-invasive nature, especially in elderly populations.

METHODS

In this study, we measured levels of 10 cytokines, and the pro-inflammatory factor, YKL-40, in plasma and saliva samples from a cohort of nondemented older adults (n = 71; 62% female; 70.3 ± 6.4 years) using sensitive electrochemiluminescence-based immunoassays.

RESULTS

We found that the mean levels of all cytokines were higher in saliva compared to plasma and that strong sex differences were observed for both saliva and plasma cytokines in this population. Comparing each cytokine between the two biofluids, we found that levels of interferon-gamma (IFNγ), interleukin (IL)-6 and tumor necrosis factor-alpha (TNFα) in blood were significantly correlated with their respective levels in saliva. We further observed that levels of these cytokines in blood were significantly correlated with additional cytokines in saliva, including IL-1β, IL-10, IL-8, IL12p70 and IL-13.

CONCLUSIONS

These findings show that inflammatory markers in saliva are associated with those found in circulation, suggesting shared inflammatory mechanisms between these two fluids. The higher levels of cytokines measured in saliva suggest that it might represent a better peripheral fluid to gauge inflammatory processes. Finally, our findings of robust sex differences in several salivary cytokines could have important implications for their potential use as disease biomarkers in the elderly and might be related to sex differences in the prevalence of age-related conditions.

CSF CXCL13 and Chitinase 3-like-1 Levels Predict Disease Course in Relapsing Multiple Sclerosis

Several biomarkers from multiple sclerosis (MS) patients' biological fluids have been considered to support diagnosis, predict disease course, and evaluate treatment response. In this study, we assessed the CSF concentration of selected molecules implicated in the MS pathological process. To investigate the diagnostic and prognostic significance of CSF concentration of target candidate biomarkers in both relapsing (RMS, n = 107) and progressive (PMS, n = 18) MS patients and in other inflammatory (OIND, n = 10) and non-inflammatory (ONIND, n = 15) neurological disorders. We measured the CSF concentration of APRIL, BAFF, CHI3L1, CCL-2, CXCL-8, CXCL-10, CXCL-12, CXCL-13 through a Luminex Assay. MS patients were prospectively evaluated, and clinical and radiological activity were recorded. CHI3L1 and CXCL13 CSF levels were significantly higher in both MS groups compared to control groups, while CCL2, BAFF, and APRIL concentrations were lower in RMS patients compared to PMS and OIND. Considering RMS patients with a single demyelinating event, higher concentrations of CHI3L1, CXCL10, CXCL12, and CXCL13 were recorded in patients who converted to clinically defined MS(CDMS). RMS patients in the CXCL13 and CHI3L1 high concentration group had a significantly higher risk of relapse (HR 12.61 and 4.57), MRI activity (HR 7.04 and 2.46), and of any evidence of disease activity (HR 12.13 and 2.90) during follow-up. CSF CXCL13 and CHI3L1 levels represent very good prognostic biomarkers in RMS patients, and therefore can be helpful in the treatment choice. Higher CSF concentrations of neuro-inflammatory biomarkers were associated with a higher risk of conversion to CDMS in patients with a first clinical demyelinating event. Differential CSF BAFF and APRIL levels between RMS and PMS suggest a different modulation of B-cells pathways in the different phases of the disease.

Inflammatory checkpoints in amyotrophic lateral sclerosis: From biomarkers to therapeutic targets

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive motor neuron damage. Due to the complexity of the ALS, so far the etiology and underlying pathogenesis of sporadic ALS are not completely understood. Recently, many studies have emphasized the role of inflammatory networks, which are comprised of various inflammatory molecules and proteins in the pathogenesis of ALS. Inflammatory molecules and proteins may be used as independent predictors of patient survival and might be used in patient stratification and in evaluating the therapeutic response in clinical trials. This review article describes the latest advances in various inflammatory markers in ALS and its animal models. In particular, this review discusses the role of inflammatory molecule markers in the pathogenesis of the disease and their relationship with clinical parameters. We also highlight the advantages and disadvantages of applying inflammatory markers in clinical manifestations, animal studies, and drug clinical trials. Further, we summarize the potential application of some inflammatory biomarkers as new therapeutic targets and therapeutic strategies, which would perhaps expand the therapeutic interventions for ALS.

Sympathetic nerve infiltration promotes stomach adenocarcinoma progression via norepinephrine/β2-adrenoceptor/YKL-40 signaling pathway

Objective

This study aimed to address the status, role, and mechanism of sympathetic nerve infiltration in the progression of stomach adenocarcinoma (STAD).

Methods

Sympathetic nerve and its neurotransmitter NE, β-ARs, and associated signaling molecules in the STAD tissues and the adjacent tissues from 46 STAD patients were examined using immunostaining, HPLC, and western blotting. The effects and mechanisms of β2-AR activation on the proliferation, migration and invasion of AGS and SGC-7901 gastric cancer (GC) cell lines were examined using CCK-8, transwell, and western blotting assays. Correlations between genes and STAD survival were analyzed using bioinformatics.

Results

Striking sympathetic nerve infiltration, elevations of NGF, TrkA, GAP43, TH, S100, NE, β2-AR, YKL-40, syndecan-1, MMP9, CD206, and CD31 were observed in the STAD tissues compared to the adjacent tissues. Activation of β2-AR in the two GC cell lines significantly amplified the expressions of NGF, YKL-40, MMP9, syndecan-1, p-STAT3 and p-ERK, and increased GC cell proliferation, migration and invasion. Bioinformatic analyses revealed positive correlations of NGF, β2-AR, syndecan-1, and macrophage infiltration, respectively, with low survival of STAD, of β2-AR respectively with STAT3, ERK1/2 (MAPK1/3), YKL-40, MMP9, and syndecan-1, and of YKL-40 with MMP9.

Conclusion

Sympathetic nerves significantly infiltrated into human STAD tissues as a result of high NGF and TrkA expressions; elevated NE led to overactivation of β2-AR-STAT3/ERK-YKL-40 signaling pathway, and finally caused cancer cell growth and invasion, M2 macrophage infiltration, angiogenesis, matrix degradation and STAD metastasis and progression.

YKL-39 is an independent prognostic factor in gastric adenocarcinoma and is associated with tumor-associated macrophage infiltration and angiogenesis

Background

Gastric cancer has a high incidence and mortality rate. Angiogenesis is necessary for tumor infiltration and metastasis and affects patient prognosis. YKL-39 has monocyte chemotactic activity and pro-angiogenic activity in some tumors. In this study, we investigated the relationship between YKL-39 and tumor-associated macrophages and microangiogenesis in gastric cancer to determine its potential as a prognostic biomarker.

Materials and methods

A total of 119 patients with gastric cancer who had undergone gastrectomy at the 940th Hospital of the Joint Security Force between 2014 and 2018 were included in this study. We assayed the protein expression of YKL-39, CD68, and CD34 by immunohistochemistry in tissues of 119 patients with gastric cancer, as well as the intracellular expression of YKL-39 and CD68 by immunofluorescence. Data were analyzed with SPSS Statistics 25.0 to explore the impact of expression of YKL-39, CD68, and CD34 in gastric cancer patients and the relationship among them.

Results

Our results show that YKL-39 was expressed in both the nucleus and cytoplasm of gastric cancer cells and tumor mesenchyme. YKL-39 protein expression was associated with the depth of tumor infiltration, lymph node metastasis, and TNM stage; CD68 protein expression was associated with lymph node metastasis and TNM stage; CD34 protein expression was not associated with clinicopathological characteristics. Expression of YKL-39 was positively correlated with CD68 and CD34 (p < 0.001), and high expression of YKL-39 was associated with poor prognosis (p < 0.05).

Conclusion

In gastric cancer, YKL-39 expression is positively correlated with the degree of tumor-associated macrophage infiltration and angiogenesis, and is a potential prognostic marker for gastric cancer.

Plasma Human Cartilage Glycoprotein‐39 Is Associated With the Prognosis of Acute Ischemic Stroke

Background

To evaluate the prognostic value of plasma YKL‐40 (human cartilage glycoprotein‐39) for acute ischemic stroke.

Methods and Results

We measured plasma YKL‐40 levels in 3377 participants from CATIS (China Antihypertensive Trial in Acute Ischemic Stroke). Study outcome data on death, major disability (modified Rankin Scale score ≥3), and vascular diseases were collected at 3 months after stroke onset. The primary outcome was defined as a combination of death and major disability. During the 3‐month follow‐up, 828 participants (24.5%) experienced major disability or died. After multivariate adjustment, the highest YKL‐40 quartile was associated with an increased risk of the primary outcome (odds ratio, 1.426 [95% CI, 1.105–1.839]; P trend =0.01) compared with the lowest quartile. Each SD increase in log‐transformed YKL‐40 level was associated with a 15.5% (95% CI, 5.6–26.3%) increased risk of the primary outcome. The multivariable‐adjusted spline regression models showed a linear dose–response relationship between YKL‐40 and clinical outcomes. Adding YKL‐40 to a model containing conventional risk factors significantly improved the reclassification power for the primary outcome (net reclassification improvement: 15.61%, P <0.001; integrated discrimination index: 0.37%, P =0.004) and marginally significantly improved the discriminatory power for the primary outcome (area under the receiver operating characteristic curve improved by 0.003, P =0.099).

Conclusions

A higher YKL‐40 level in the acute phase of ischemic stroke was associated with an increased risk of mortality and major disability at 3 months after stroke, indicating that YKL‐40 may play an important role as a prognostic marker of ischemic stroke.

Registration

URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01840072.

Role of Chitinase 3-like 1 as a Biomarker in Multiple Sclerosis: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVES

Multiple sclerosis (MS) is an autoimmune disease confined in the CNS, and its course is frequently subtle and variable. Therefore, predictive biomarkers are needed. In this scenario, we conducted a systematic review and meta-analysis to evaluate the reliability of chitinase 3-like 1 as a biomarker of MS.

METHODS

Research through the main scientific databases (PubMed, Scopus, Web of Science, and Cochrane Library) published from January 2010 to December 2020 was performed using the following keywords: "chitinase 3-like 1 and multiple sclerosis" and "YKL40 and multiple sclerosis." Articles were selected according to the 2020 updated Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines by 2 authors independently, and data were extracted; 20 of the 90 studies screened were included in the meta-analysis. The main efficacy measure was represented by the standardized mean difference of CSF and blood CHI3L1 levels; Review Manager version 5.4 and R software applications were used for analysis.

RESULTS

Higher levels of CHI3L1 were found in CSF of 673 patients with MS compared with 336 healthy controls (size-weighted mean difference [SMD] 50.88; 95% CI = 44.98-56.79; p < 0.00001) and in 461 patients with MS than 283 patients with clinically isolated syndrome (CIS) (SMD 28.18; 95% CI = 23.59-32.76; p < 0.00001). Mean CSF CHI3L1 levels were significantly higher in 561 converting than 445 nonconverting CIS (SMD 30.6; 95% CI = 28.31-32.93; p < 0.00001). CSF CHI3L1 levels were significantly higher in patients with primary progressive MS (PPMS) than in patients with relapsing-remitting MS (RRMS) (SMD 43.15; 95% CI = 24.41-61.90; p < 0.00001) and in patients with secondary progressive MS (SMD 41.86 with 95% CI = 32.39-51.33; p < 0.00001). CSF CHI3L1 levels in 407 patients with MS during remission phase of disease were significantly higher than those in 395 patients with MS with acute relapse (SMD 10.48; 95% CI = 08.51-12.44; p < 0.00001). The performances of CHI3L1 in blood for differentiating patients with MS from healthy controls were not significant (SMD 0.48; 95% CI = -1.18 to 2.14; p: 0.57).

DISCUSSION

CSF levels of CHI3L1 have a strong correlation with the MS pathologic course, in particular with the mechanism of progression of the disease; it helps to distinguish the PPMS from the RRMS. The potential role of CHI3L1 in serum needs to be further studied in the future.

Neuroinflammation in Huntington's Disease: A Starring Role for Astrocyte and Microglia

Huntington's disease (HD) is a neurodegenerative genetic disorder caused by a CAG repeat expansion in the huntingtin gene. HD causes motor, cognitive, and behavioral dysfunction. Since no existing treatment affects the course of this disease, new treatments are needed. Inflammation is frequently observed in HD patients before symptom onset. Neuroinflammation, characterized by the presence of reactive microglia, astrocytes and inflammatory factors within the brain, is also detected early. However, in comparison to other neurodegenerative diseases, the role of neuroinflammation in HD is much less known. Work has been dedicated to altered microglial and astrocytic functions in the context of HD, but less attention has been given to glial participation in neuroinflammation. This review describes evidence of inflammation in HD patients and animal models. It also discusses recent knowledge on neuroinflammation in HD, highlighting astrocyte and microglia involvement in the disease and considering anti-inflammatory therapeutic approaches.

Chitooligosaccharides Improve the Efficacy of Checkpoint Inhibitors in a Mouse Model of Lung Cancer

YKL-40 (also named chitinase 3 like-1 protein [CHI3L1]) is a secreted chitinase-like protein which is upregulated in cancers and suggested to have pro-tumorigenic activity. YKL-40 lacks enzymatic function, but it can bind carbohydrates such as chitin. Chitooligosaccharides (COS) derived from deacetylation and hydrolysis of chitin might be used for the blockade of YKL-40 function. Here, public single-cell RNA sequencing datasets were used to elucidate the cellular source of YKL-40 gene expression in human tumors. Fibroblasts and myeloid cells were the primary sources of YKL-40. Screening of YKL-40 gene expression in syngeneic mouse cancer models showed the highest expression in the Lewis lung carcinoma (LL2) model. LL2 was used to investigate COS monotherapy and combinations with immune checkpoint inhibitors (anti-PD-L1 and anti-CTLA-4) (ICIs) and radiotherapy (8 Gy × 3) (RT). COS tended to reduce plasma YKL-40 levels, but it did not affect tumor growth. LL2 showed minimal responses to ICIs, or to RT alone. Interestingly, ICIs combined with COS led to delayed tumor growth. RT also enhanced the efficacy of ICIs; however, the addition of COS did not further delay the tumor growth. COS may exert their anti-tumorigenic effects through the inhibition of YKL-40, but additional functions of COS should be investigated.

The lncRNAs/miR-30e/CHI3L1 Axis Is Dysregulated in Systemic Sclerosis

Systemic sclerosis (SSc) is an autoimmune disease with completely undefined etiology and treatment difficulties. The expression of both protein coding and non-coding RNAs is dysregulated during disease development. We aimed to examine a possible regulatory axis implemented in the control of chitinase-3 like protein 1 (CHI3L1) or YKL-40, an inflammation-associated glycoprotein, shown to be elevated in SSc. A panel of seven miRNAs and three lncRNAs potentially involved in the control of CHI3L1 were selected on the basis of in silico analysis. TagMan assay was used to evaluate the expression levels of miRNAs and RT-qPCR for lncRNAs in white blood cells (WBCs) and plasma from SSc patients and healthy controls. Among the eight screened miRNAs, miR-30e-5p (p = 0.04) and miR-30a-5p (p = 0.01) were significantly downregulated in WBCs and plasma of SSc patients, respectively. On the contrary, the expression of the metastasis associated lung adenocarcinoma transcript 1 (MALAT1) (p = 0.044) and the Nuclear enriched abundant transcript 1 (NEAT1) (p = 0.008) in WBCs was upregulated compared to the controls. Increased levels of MALAT1 and NEAT1 could be associated with the downregulation of miR-30e-5p and miR-30a-5p expression in WBCs and plasma. We present novel data on the involvement of a possible regulatory axis lncRNAs/miR-30e/CHI3L1 in SSc and hypothesize that MALAT1 and NEAT1 could act as miR-30e-5p and miR-30a-5p decoys. This may be a reason for the increased serum levels of CHI3L1 in SSc patients.

Targeting protumor factor chitinase-3-like-1 secreted by Rab37 vesicles for cancer immunotherapy

Background: Chitinase 3-like-1 (CHI3L1) is a secretion glycoprotein associated with the immunosuppressive tumor microenvironment (TME). The secretory mode of CHI3L1 makes it a promising target for cancer treatment. We have previously reported that Rab37 small GTPase mediates secretion of IL-6 in macrophages to promote cancer progression, whereas the roles of Rab37 in the intracellular trafficking and exocytosis of CHI3L1 are unclear.

Methods: We examined the concentration of CHI3L1 in the culture medium of splenocytes and bone marrow derived macrophages (BMDMs) from wild-type or Rab37 knockout mice, and macrophage or T cell lines expressing wild type, active GTP-bound or inactive GDP-bound Rab37. Vesicle isolation, total internal reflection fluorescence microscopy, and real-time confocal microscopy were conducted. We developed polyclonal neutralizing-CHI3L1 antibodies (nCHI3L1 Abs) to validate the therapeutic efficacy in orthotopic lung, pancreas and colon cancer allograft models. Multiplex fluorescence immunohistochemistry was performed to detect the protein level of Rab37 and CHI3L1, and localization of the tumor-infiltrating immune cells in allografts from mice or tumor specimens from cancer patients.

Results: We demonstrate a novel secretion mode of CHI3L1 mediated by the small GTPase Rab37 in T cells and macrophages. Rab37 mediated CHI3L1 intracellular vesicle trafficking and exocytosis in a GTP-dependent manner, which is abolished in the splenocytes and BMDMs from Rab37 knockout mice and attenuated in macrophage or T cell lines expressing the inactive Rab37. The secreted CHI3L1 activated AKT, ß-catenin and NF-κB signal pathways in cancer cells and macrophages to foster a protumor TME characterized by activating M2 macrophages and increasing the population of regulatory T cells. Our developed nCHI3L1 Abs showed the dual properties of reducing tumor growth/metastases and eliciting an immunostimulatory TME in syngeneic orthotopic lung, pancreas and colon tumor models. Clinically, high plasma level or intratumoral expression of CHI3L1 correlated with poor survival in 161 lung cancer, 155 pancreatic cancer and 180 colon cancer patients.

Conclusions: These results provide the first evidence that Rab37 mediates CHI3L1 secretion in immune cells and highlight nCHI3L1 Abs that can simultaneously target both cancer cells and tumor microenvironment.