Chitinase 3-like 1 Expression Research Articles

Anti-chitinase-3-like 1 antibody attenuated atopic dermatitis-like skin inflammation through inhibition of STAT3-dependent CXCL8 expression.

Chitinase-3-like 1 (CHI3L1) causes skin inflammation in the progression of atopic dermatitis. We investigated if anti-CHI3L1 antibody could prevent the development of atopic dermatitis and its mechanisms of action. The effect of CHI3L1 antibody on phthalic anhydride-induced atopic dermatitis animal model and in vitro reconstructed human skin (RHS) model were investigated. Expression and release of atopic dermatitis-related cytokines were determined using an enzyme-linked immunosorbent assay, and RT-qPCR, STAT3 and CXCL8 signalling were measured by western blotting. Anti-CHI3L1 antibody suppressed phthalic anhydride-induced epidermal thickening, clinical score, IgE level and infiltration of inflammatory cells, and reduced phthalic anhydride-induced inflammatory cytokines concentration. In addition, CHI3L1 antibody treatment inhibited the expression of STAT3 activity in phthalic anhydride-treated skin. It was also confirmed that CHI3L1 antibody treatment alleviated atopic dermatitis-related inflammation in the RHS model. The inhibitory effects of CHI3L1 antibody was similar or more effective compared with that of the IL-4 antibody. We further found that CHI3L1 is associated with CXCL8 by protein-association network analysis. siRNA of CHI3L1 blocked the mRNA levels of CHI3L1, IL-1β, IL-4, CXCL8, TSLP, and the expression of CHI3L1 and p-STAT, and the level of CXCL8, whereas recombinant level of CXCL8 was elevated. Moreover, siRNA of STAT3 reduced the mRNA level of these cytokines. CHI3L1 and p-STAT3 expression correlated with the reduced CXCL8 level in the RHS in vitro model. Our data demonstrated that CHI3L1 antibody could be a promising effective therapeutic drug for atopic dermatitis.

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

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. 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. 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. 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.

Chitinase 3-like-1 Expression in the Microenvironment Is Associated with Neutrophil Infiltration in Bladder Cancer.

Bladder cancer is a common cancer with well-established therapeutic strategies. However, recurrence occurs in 50% of patients with non-muscle-invasive bladder cancer, and 20% of patients progress to muscle-invasive bladder cancer. The 5-year survival rate for muscle-invasive bladder cancer patients is disappointingly low, ranging from 36% to 48%. A molecular marker of interest is chitinase 3-like-1 (CHI3L1), which is elevated in various cancers, including bladder cancer. In addition to its role in cancer cells, CHI3L1 also has regulatory abilities in immune cells. Neutrophil infiltration has been shown to positively correlate with overall survival, progression-free survival, and relapse-free survival in bladder cancer patients. However, the relationship between CHI3L1 and neutrophils remain poorly understood. Therefore, this study investigated the relationship between CHI3L1 level and protumor neutrophil infiltration in bladder cancer. We analyzed the GSE128959 dataset and the data of a bladder cancer cohort undergoing chemotherapy. We observed higher expression of CHI3L1 in bladder cancer patients with invasive or chemotherapy-resistance. Our results revealed a positive correlation between CHI3L1 expression and protumor neutrophil infiltration. Elevated CHI3L1 expression was associated with genes which were related to the recruitment and infiltration of neutrophils. Consequently, CHI3L1 may serve as a novel evaluation factor for the degree of neutrophil infiltration in advanced bladder cancer in those scheduled for chemotherapy.

Differential expression of Chitinase 3-Like 1 protein in appendicitis and appendix carcinomas.

Chitinase 3-Like 1 (CHI3L1) has been used as an inflammatory biomarker for a variety of diseases, but its expression in acute appendicitis and appendix carcinomas remains unclear. Sixty cases of patients were studied, including 46 acute appendicitis and 14 appendix carcinomas. We divided the acute appendicitis group into acute uncomplicated appendicitis (AUA), suppurative appendicitis (SA), and gangrenous appendicitis (GA). The appendix carcinoma group was divided into appendiceal neuroendocrine neoplasms (ANENs) and appendiceal mucinous neoplasms (AMN). Controls were 32 healthy donors. Blood neutrophil to lymphocyte ratio (NLR), CHI3L1, C-reactive protein (CRP), interleukin-6 (IL-6), and serum amyloid A (SAA) were measured in the patients. Meanwhile, immunohistochemistry and immunofluorescence were used to identify the expression level and location of CHI3L1 in different cell types in appendix tissues. Compared with the controls, CHI3L1 serum levels were up-regulated in SA, GA, and AMN groups, while no significant difference was observed in the AUA and ANEN groups. Immunofluorescence revealed that CHI3L1 expression was high in macrophages and adenocarcinoma cells of appendix tissues but not in the neuroendocrine carcinoma tissues. Moreover, levels of NLR and CRP in the SA and GA groups were considerably higher than in the control group. IL-6 and SAA in SA, GA, ANENs, and AMN groups were also increased compared with the control group. In addition, CHI3L1 displayed good performance in predicting appendicitis, with an AUC of 0.862. CHI3L1 was highly expressed in acute appendicitis and appendiceal mucinous neoplasms, which can be used as a novel biomarker predicting appendicitis.

Abstract P2014: Chitinase-3-like-1 Is A Neutrophil Secreted Factor That Antagonizes Replacement Fibrosis And Exacerbates Cardiac Dysfunction After Myocardial Infarction.

Patient studies show that chitinase 3-like 1 (CHI3L1) is a novel biomarker of coronary artery disease (CAD). Furthermore, CHI3L1 plasma level is a strong predictor of all-cause of mortality in patients with CAD, and is a strong indicator of heart failure progression. Studies from our lab revealed that CHI3L1 is elevated in hearts after MI, and systemic administration of CHI3L1 in mice exacerbated post-MI fibrosis and left ventricular dysfunction. The goal of the current study was to delineate the mechanism of CHI3L1 secretion after MI and test the impact of CHI3L1 on post-MI replacement fibrosis. We found that CHI3L1 levels were rapidly increased in infarcted regions of LV at 2 d after MI and remained significantly elevated at 7 and 35 d (n=5-11/group, p&lt;0.05). More detailed analysis revealed that neutrophils are the main source of CHI3L1. Protein CHI3L1 expression in neutrophils was 3-4 orders of magnitude higher compared with cardiac fibroblasts, macrophages, endothelial cells, and cardiomyocytes (n=3-5, p&lt;0.0001). Next, we found that Chil1 -/- subjected to permanent coronary artery ligation showed decreased end-systolic and diastolic volumes and increased ejection fraction measured at 7 and 35 d with echocardiography (n=7-10/group, p&lt;0.05 at 7 d; n=16-20/group, p&lt;0.05 at 35 d). Histological analysis of hearts displayed no change in scar size but left ventricular expansion index was reduced and the infarcted wall thickness was increased in Chil1 -/- mice compared to their Chil1 +/+ controls (n=16-18/group, p&lt;0.01). We found no difference in cardiomyocyte cross-sectional area (WGA staining) and capillary density (isolectin B4 staining). These data provide proof of principle evidence that CHI3L1 is a neutrophil secreted factor that has an adverse effect on replacement fibrosis after MI. Future efforts will focus on the mechanism of actions of CHI3L1 and the identification of strategies to inhibit detrimental actions of CHI3L1 on replacement fibrosis and heart failure.

Chitinase 3-like 1 is involved in the induction of IL-8 expression by double-stranded RNA in airway epithelial cells

Viral respiratory infection causes inflammatory lung disease. Chitinase 3-like 1 (CHI3L1) contributes to airway inflammation, but its role in human airway epithelial cells following viral infection is unclear. Thus, we investigated whether CHI3L1 regulates inflammatory responses caused by viral infections in airway epithelial cells. Human bronchial epithelial cells, BEAS-2B, were stimulated with a synthetic analog of viral double-stranded RNA, polyinosinic:polycytidylic acid (poly(I:C)). To confirm the specific role of CHI3L1, CHI3L1 was knocked down in BEAS-2B cells using shRNA lentivirus. The expression of CHI3L1 and proinflammatory cytokines such as IL-8 and phosphorylation of mitogen-activated protein kinase (MAPK) pathways were analyzed. In addition to poly(I:C), BEAS-2B cells were infected with the human respiratory syncytial virus (RSV) A2 strain, and CHI3L1 and IL-8 expression was analyzed. Stimulating the cells with poly(I:C) increased CHI3L1 and IL-8 expression, whereas IL-8 expression was abrogated in CHI3L1 knockdown BEAS-2B cells. Poly(I:C) stimulation of BEAS-2B cells resulted in phosphorylation of MAPK pathways, and inhibition of MAPK pathways significantly abolished IL-8 secretion. Phosphorylation of MAPK pathways was diminished in CHI3L1 knockdown BEAS-2B cells. Infection with RSV increased CHI3L1 and IL-8 expression. IL-8 expression induced by RSV infection was abrogated in CHI3L1 knockdown cells. In conclusion, CHI3L1 may be involved in IL-8 secretion by regulating MAPK pathways during respiratory viral infections in airway epithelial cells.

Nrf2 Regulates CHI3L1 to Suppress Inflammation and Improve Post-Traumatic Osteoarthritis

IntroductionPost-traumatic osteoarthritis (PTOA) is an inflammatory condition that occurs following mechanical joint trauma and that results in joint degeneration. This study sought to evaluate the regulatory function of nuclear factor erythroid 2-related factor 2 (Nrf2) in a murine model of anterior cruciate ligament transection (ACLT)-induced PTOA and in an in vitro model of synoviocyte inflammation induced by LPS treatment with the goal of exploring the role of chitinase 3-like-1 (CHI3L1) in this pathogenic context.MethodsPTOA model mice were intra-articularly injected with Nrf2 overexpression lentiviral vector, and safranin O-fast green staining as well as the Osteoarthritis Research Society International (OARSI) Scoring System were used to evaluate the severity of cartilage damage. Protein expression in the synovial tissue was evaluated by Western blotting, immunohistochemical staining, and ELISA. Additionally, murine synoviocytes were infected with Nrf2 overexpression lentivirus and stimulated with LPS. The levels of inflammatory cytokines were detected by ELISA. ROS levels were measured using dihydroethidium (DHE) dye.ResultsWe determined that the overexpression of Nrf2 was sufficient to reduce cartilage degradation in the context of PTOA in vivo, and we observed a significant decrease in the expression of matrix metalloproteinase 13 (MMP13) in the articular cartilage of samples from mice overexpressing Nrf2 relative to control mice. Synovial CHI3L1 expression and serum TNF-α, IL-1β, and IL-6 levels were reduced in animals overexpressing this transcription factor relative to PTOA model controls. Consistent with these findings, murine synoviocytes treated with LPS exhibited dose-dependent increases in ROS, TNF-α, IL-1β, IL-6, Nrf2, and CHI3L1 levels, whereas Nrf2 overexpression was sufficient to suppress these increases.ConclusionOur data indicated that Nrf2 negatively regulates CHI3L1, suggesting that this signaling axis may regulate PTOA progression and may thus be a viable therapeutic target in individuals affected by this condition.

Chitinase 3-like 1 is a profibrogenic factor overexpressed in the aging liver and in patients with liver cirrhosis

Older age at the time of infection with hepatitis viruses is associated with an increased risk of liver fibrosis progression. We hypothesized that the pace of fibrosis progression may reflect changes in gene expression within the aging liver. We compared gene expression in liver specimens from 54 adult donors without evidence of fibrosis, including 36 over 40 y old and 18 between 18 and 40 y old. Chitinase 3-like 1 (CHI3L1), which encodes chitinase-like protein YKL-40/CHI3L1, was identified as the gene with the greatest age-dependent increase in expression in liver tissue. We investigated the cellular source of CHI3L1 in the liver and its function using liver tissue specimens and in vitro models. CHI3L1 expression was significantly higher in livers of patients with cirrhosis of diverse etiologies compared with controls represented by patients who underwent liver resection for hemangioma. The highest intrahepatic CHI3L1 expression was observed in cirrhosis due to hepatitis D virus, followed by hepatitis C virus, hepatitis B virus, and alcohol-induced cirrhosis. In situ hybridization of CHI3L1 messenger RNA (mRNA) identified hepatocytes as the major producers of CHI3L1 in normal liver and in cirrhotic tissue, wherein hepatocytes adjacent to fibrous septa showed higher CHI3L1 expression than did those in more distal areas. In vitro studies showed that recombinant CHI3L1 promotes proliferation and activation of primary human hepatic stellate cells (HSCs), the major drivers of liver fibrosis. These findings collectively demonstrate that CHI3L1 promotes liver fibrogenesis through a direct effect on HSCs and support a role for CHI3L1 in the increased susceptibility of aging livers to fibrosis progression.

CHI3L1 (Chitinase 3 Like 1) upregulation is associated with macrophage signatures in esophageal cancer

ABSTRACT Chitinase-3 like-protein-1 (CHI3L1) has been found to be overexpressed in many cancers and increased CHI3L1 level in serum seems to correlate with a poor prognosis in patients with metastatic cancer. However, the expression of CHI3L1 and its potential role in esophageal cancer remains unclear. We retrieved publicly available RNA-seq datasets of esophageal cancer tissues and normal esophageal tissues. We analyzed the correlation between CHI3L1 expression with different clinical parameters (such as T stages, N stage, response to treatment and tumor residues after treatment), the relationship between CHI3L1 expression level and prognosis, and the relationship between CHI3L1 expression and different immune cell signatures in esophageal cancer tissues. A transgenic mouse model of esophageal carcinoma was used to validate CHI3L1 expression and its association with macrophage signature gene expression. The effect of recombinant CHI3L1 on macrophage polarization was assessed in cell model. We showed the upregulation of CHI3L1 in esophageal cancer tissues in comparison to normal esophageal tissues, and its upregulation was positively associated with tumor size. The analysis of immunological signatures and CHI3L1 expression indicated that CHI3L1 level was highly correlated with increased expression of macrophage signature genes in esophageal tumor tissues. CHI3L1 was also upregulated in the esophagus dysplasia tissues in a transgenic mouse model. Recombinant CHI3L1 treatment favored M2 gene expression in LPS-stimulated RAW 264.7 macrophage cell line. CHI3L1 overexpression may favor macrophage recruitment in esophageal tumor tissues. Future studies are needed to delineate the mechanisms of CHI3L1-mediated macrophage recruitment and polarization in tumor tissues.

Chitinase 3-like-1 and fibronectin in the cargo of extracellular vesicles shed by human macrophages influence pancreatic cancer cellular response to gemcitabine.

Tumour-associated macrophages have been implicated in pancreatic ductal adenocarcinoma (PDAC) therapy response and Extracellular vesicles (EVs) shed by macrophages might have a role in this process. Here, we demonstrated that large EVs released by anti-inflammatory human macrophages decreased PDAC cellular sensitivity to gemcitabine. Using proteomic analysis, chitinase 3-like-1 (CHI3L1) and fibronectin (FN1) were identified as two of the most abundant proteins in the cargo of macrophages-derived EVs. Overexpression of CHI3L1 and FN1, using recombinant human proteins, induced PDAC cellular resistance to gemcitabine through ERK (extracellular-signal-regulated kinase) activation. Inhibition of CHI3L1 and FN1 by pentoxifylline and pirfenidone, respectively, partially reverted gemcitabine resistance. In PDAC patient samples, CHI3L1 and FN1 were expressed in the stroma, associated with the high presence of macrophages. The Cancer Genome Atlas analysis revealed an association between CHI3L1 and FN1 gene expression, overall survival of PDAC patients, gemcitabine response, and macrophage infiltration. Altogether, our data identifies CHI3L1 and FN1 as potential targets for pharmacological inhibition in PDAC. Further pre-clinical in vivo work is warranted to study the possibility of repurposing pentoxifylline and pirfenidone as adjuvant therapies for PDAC treatment.

The clinical significance of serum chitinase 3-like 1 in hepatitis B-related chronic liver diseases.

AimIn the present study, we purposed to determine serum chitinase 3‐like 1 (CHI3L1) expression characteristics in chronic liver diseases monoinfected with hepatitis B virus and analyze its diagnostic value in liver fibrosis.MethodsA total of 467 chronic hepatitis B (CHB) patients, 312 liver cirrhosis (LC) patients, and 104 hepatocellular carcinoma (HCC) patients at our institution were enrolled, and clinical indicators were analyzed.ResultsOur data have shown that the expression level of serum CHI3L1 was steadily increased from CHB to LC to HCC (P < .001). Serum CHI3L1 expression levels were positively associated with liver stiffness measurement (LSM), fibrosis‐4 (FIB‐4) index, aspartate aminotransferase‐to‐platelet ratio index (APRI), and HCC stage. The receiver operating characteristic (ROC) curve proved that serum CHI3L1 was superior to other noninvasive methods (LSM, FIB‐4, and APRI) with an area under the ROC curve (AUC) of 0.97 in diagnosing significant fibrosis.ConclusionsSerum CHI3L1 harbors significant clinical value in chronic liver diseases infected with hepatitis B virus, especially in the diagnosis of fibrosis.

NF-κB-mediated inhibition of microRNA-149-5p regulates Chitinase-3-like 1 expression in human airway epithelial cells

Lower respiratory tract infections are among the most common causes of death worldwide. Main pathogens leading to these severe infections are viruses and gram-positive bacteria that activate toll-like receptor (TLR)-mediated immune responses via pathogen-associated molecular patterns. One protective factor induced during infection is Chitinase-3-like 1 (CHI3L1), which exerts various functions, e.g. in host cell proliferation and bacterial counteraction, and has been proposed as a biomarker in several acute and chronic inflammatory conditions. MicroRNAs (miR) have become important regulators of inflammation and infection and are considered therapeutic targets in recent years. However, it is not known whether microRNAs play a role in the regulation of CHI3L1 expression in TLR-mediated respiratory epithelial cell inflammation. In this study, we analysed the pre- and post-transcriptional regulation of CHI3L1 by TLRs in bronchial epithelial cells. Therefore, we stimulated BEAS-2B cells with the bacterial TLR2-ligand lipoteichoic acid or the viral dsRNA analogue poly(I:C). We observed an increase in the expression of CHI3L1, which was dependent on TNF-α-mediated NF-κB activation in TLR2- and TLR3-activated cells. Moreover, TLR2 and − 3 stimulation caused downregulation of the microRNA miR-149-5p, an effect that could be suppressed by inhibiting NF-κB translocation into the nucleus. Luciferase reporter assays identified a direct interaction of miR-149-5p with the CHI3L1 3´untranslated region. This interaction was confirmed by inhibition and overexpression of miR-149-5p in BEAS-2B cells, which altered the expression levels of CHI3L1 mRNA. In summary, miR-149-5p directly regulates CHI3L1 in context of TLR-mediated airway epithelial cell inflammation and may be a potential therapeutic target in inflammation and other diseases.

Chitinase 3-like 1 Produced By Fibrocytes Promotes Myelofibrosis

Introduction Monocyte-derived fibrocytes are spindle-shaped fibroblast-like blood cells derived from a sub-population of CD14+ monocytes. Recent studies have shown that fibrocytes play a key role in the pathogenesis of primary myelofibrosis (MF), and these cells have attracted attention as novel therapeutic targets for MF treatment. Using a Romiplostim (Rom)-induced murine MF model, we have previously reported that fibrocyte differentiation, which is directly induced by activating the thorombopoietin receptor signaling pathway, can potentially trigger the progression of MF (Leukemia 2017; 31: 2709). However, the precise molecular mechanism of fibrocyte activity in MF have not been elucidated. To address this question, we compared the RNA sequencing-based gene expression profiles of monocytes and fibrocytes and detected that fibrocytes exhibited a higher level of Chitinase 3-like 1 (CHI3L1) expression than monocytes. CHI3L1, an 18-glycosyl hydrolase-related molecule, is a member of the enzymatically inactive chitinase-like protein family. These proteins are associated with inflammation, tissue remodeling, and organ fibrosis. Therefore, we hypothesized that CHI3L1 produced by fibrocytes is potentially involved in the progression of MF and could be a therapeutic target. In the present study, we evaluated CHI3L1 using serum samples obtained from patients with myeloproliferative neoplasms (MPN) and a Rom-induced murine MF model. Methods Monocytes and fibrocytes (Day 9 and Day 12) were prepared using peripheral blood samples from healthy volunteers. Following total RNA extraction, RNA qualification, and library preparation, a Hiseq4000 (Illumina) system was used for RNA sequencing. ELISA-based analyses were performed using the supernatant of the blood cells to confirm the presence of the CHI3L1 protein. Furthermore, we determined the serum CHI3L1 levels of MPN patients with or without MF using ELISA-based analyses. Overall, 21 patients without MF and 31 patients with MF (MF-1 to MF-3) were enrolled after obtaining written informed consent. Using the Rom-induced murine MF model, we performed in vivo analyses of Chi3l1. Female C57BL/6J mice (8-week-old) were administered with 1 mg/kg Rom once a week for 2 or 3 weeks, following which serum samples, spleens, and bone marrow samples were examined. To eliminate fibrocytes, clodronate liposomes were administered to mice. Chi3l1-deficient (Chi3l1−/−) mice were administered with Rom in the same manner. Following these treatments, RT-PCR and histopathological analyses of bone marrow were conducted. Non-contact co-culture assays of human fibrocytes and fibroblasts were performed using the human fibroblast cell line HS-5 to evaluate the interaction between CHI3L1 and fibroblasts. HS-5 cells were cultured using the supernatant of fibrocytes with or without the neutralizing antibody for CHI3L1 and mRNA expression of HS-5 cells was examined. Results Comparing the RNA sequencing gene expression profiles of monocytes and fibrocytes revealed a significant increase in CHI3L1 expression associated with fibrocyte differentiation. ELISA-based analyses of human monocyte and fibrocyte supernatants confirmed that the secretion of CHI3l1 protein concurred with the amount of mRNA expression (P &lt; 0.01) (a). We demonstrated that CHI3L1 levels were elevated in in serum samples obtained from MPN patients with MF (N = 31) compared with those obtained from patients without MF (N = 21; P = 0.027) (b). High levels of Chi3l1 mRNA expression were observed in the bone marrow of the Rom-induced murine MF model (P &lt; 0.01), which was abrogated by clodronate treatment. Furthermore, compared with wild-type mice, Chi3l1−/− mice showed fewer reticulin fibers in silver-stained bone marrow sections (c) and significantly decreased Col3A1 and Acta2 mRNA expression in the bone marrow (P &lt; 0.05). In addition, co-culture assays demonstrated that HS-5 cells cultured with the supernatant of fibrocytes showed significantly higher levels of COL1A1 and COL3A1 expression (P &lt; 0.05) than that of monocytes and the addition of CHI3L1 neutralizing antibody abrogated these increases (d). Conclusion CHI3L1 is involved in the interaction between fibrocytes and fibroblasts and this molecule exacerbates the progression of bone marrow fibrosis by promoting the production of the extracellular matrix. Therefore, CHI3L1 could be a potential therapeutic target for MF treatment. Figure Disclosures Makishima: Bristol-Myers Squibb: Research Funding. Komatsu:Wako Pure Chemical Industries, Ltd.: Research Funding; Fuso Pharmaceutical Industries, Ltd.: Research Funding; Takeda Pharmaceutical Company Limited: Research Funding, Speakers Bureau; Pharma Essentia: Research Funding, Speakers Bureau; Novartis K.K: Speakers Bureau. Kimura:JSPS KAKENHI: Research Funding.

Chitinase 3-like 1 deficiency ameliorates liver fibrosis by promoting hepatic macrophage apoptosis.

AimChitinase 3‐like 1 (CHI3L1), an 18‐glycosyl hydrolase‐related molecule, is a member of the enzymatically inactive chitinase‐like protein family. Serum levels of CHI3L1 are strongly correlated with hepatic fibrosis progression during many liver diseases. Therefore, this protein could be involved in the development of hepatic fibrosis pathology; however, its role has not been elucidated. We aimed to elucidate its role in the pathophysiology of liver fibrosis.MethodsChitinase 3‐like 1‐deficient (Chi3l1 −/−) mice were given carbon tetrachloride twice per week for 4 weeks or fed a methionine choline‐deficient diet for 12 weeks to generate mouse liver fibrosis models. Human fibrotic liver tissues were also examined immunohistochemically.ResultsIn human and mouse fibrotic livers, CHI3L1 expression was mainly localized to hepatic macrophages, and the intrahepatic accumulation of CHI3L1+ macrophages was significantly enhanced compared to that in control livers. In the two mouse models, hepatic fibrosis was significantly ameliorated in Chi3l1 −/− mice compared to that in wild‐type mice, which was dependent on hepatic macrophages. The accumulation and activation of hepatic macrophages was also significantly suppressed in Chi3l1 −/− mice compared to that in wild‐type mice. Furthermore, apoptotic hepatic macrophages were significantly increased in Chi3l1 −/− mice. Chitinase 3‐like 1 was found to inhibit hepatic macrophage apoptosis by suppressing Fas expression and activating Akt signaling in an autocrine manner, which resulted in hepatic macrophage accumulation and activation, exaggerating liver fibrosis.ConclusionsChitinase 3‐like 1 exacerbates liver fibrosis progression by suppressing apoptosis in hepatic macrophages. Therefore, this might be a potential therapeutic target for the treatment of liver fibrosis.

Correlation of Expression of CHI3L1 and Nogo-A and their Role in Angiogenesis in Invasive Ductal Breast Carcinoma.

Chitinase 3 like 1 (CHI3L1) is a secretion glycoprotein. Elevated levels of this protein are observed in cancer diseases. The biological role of CHI3L1 is not yet fully known, but the connection between CHI3L1 and angiogenesis has been shown. Recent reports also describe the association of Nogo isoforms and Nogo-B receptor (NgBR) with a proliferative potential, cancer cell invasiveness, and angiogenesis. The aim of this study was to evaluate the levels of CHI3L1, Nogo-A, Nogo-A/B, and NgBR and correlate them with clinical-pathological data, to study their role in angiogenesis in invasive ductal breast carcinoma (IDC). A total of 77 IDC cases were used in the study. Immunohistochemistry was used to determine the level of expression of CHI3L1, Nogo-A, Nogo-A/B, NgBR and vascular endothelial growth factors (VEGFA, VEGFC and VEGFD). The obtained results were subjected to statistical analysis including clinicalpathological data. A statistically significant positive correlation of CHI3L1 and Nogo-A expression (r=0.474, p>0.0001) and a positive correlation of Nogo-A and VEGFC expression (r=0.280, p=0.013) were found. CHI3L1 and Nogo-A are important in angiogenesis in IDC.

High expression of Chitinase 3-like-1 is an unfavorable prognostic factor in urothelial carcinoma of upper urinary tract and urinary bladder

BackgroundMetabolic adaptation in cancer cells is important for cancer cell survival. Alternation in cellular metabolism getting more energy to support cell proliferation played a critical role in disease progression. We initially analyzed the public transcriptome of urothelial carcinoma in Gene Expression Omnibus database (GSE31684) with particular focus on genes associated with carbohydrate metabolism, and found that Chitinase 3-like-1 (CHI3L1) was a significantly up-regulated gene associated with advanced disease status. This study was aimed to evaluate the expression and prognostic significance of CHI3L1 in upper urinary tract urothelial carcinoma (UTUC) and urinary bladder urothelial carcinoma (UBUC). Materials and MethodsWe performed immunohistochemical study to evaluate CHI3L1 expression in 2 well-defined cohorts of urothelial carcinoma, including UTUC (n = 340) and UBUC (n = 295). CHI3L1 expression level was determined by H-score method. The associations between CHI3L1 expression and clinicopathological features, disease-specific survival (DSS) and metastasis-free survival (MFS) were analyzed. ResultsHigh expression of CHI3L1 was significantly associated with adverse clinicopathological features in UTUC or UBUC, including advanced tumor status (pT), nodal metastasis, high histological grade, vascular invasion, perineural invasion, and high mitotic activity (all P < 0.05). Kaplan-Meier survival analysis revealed that patients with high CHI3L1 expression had shorter DSS and MFS in both UTUC and UBUC (all P < 0.05). In multivariate survival analyses, high expression of CHI3L1 acted as an independent prognostic factor for worse DSS (P < 0.001 in UTUC and P = 0.036 in UBUC) and MFS (P = 0.002 in UTUC and P = 0.003 in UBUC) in both UTUC and UBUC groups. ConclusionsHigh expression of CHI3L1 was significantly associated with aggressive clinicopathological features and acted as an independent prognostic factor for worse outcome in urothelial carcinoma.

K284-6111 prevents the amyloid beta-induced neuroinflammation and impairment of recognition memory through inhibition of NF-\u03baB-mediated CHI3L1 expression

BackgroundAlzheimer’s disease, which is pathologically characterized by an excessive accumulation of amyloid beta (Aβ) fibrils, is a degenerative brain disease and the most common cause of dementia. In a previous study, it was reported that an increased level of CHI3L1 in plasma was found in AD patients. We investigated the inhibitory effect of 2-({3-[2-(1-cyclohexen-1-yl)ethyl]-6,7-dimethoxy-4-oxo-3,4-dihydro-2-quinazolinyl}sulfanyl)-N-(4-ethylphenyl)butanamide (K284-6111), an inhibitor of chitinase 3 like 1 (CHI3L1), on memory impairment in Aβ1–42-infused mice, and microglial BV-2 cells and astrocytes.MethodsWe examined whether K284-6111 (3 mg/kg given orally for 4 weeks) prevents amyloidogenesis and memory loss in Aβ1–42-induced AD mice model. After intracerebroventrical (ICV) infusion of Aβ1–42 for 14 days, the cognitive function was assessed by the Morris water maze test and passive avoidance test. K284-6111 treatment was found to reduce Aβ1–42-induced memory loss.ResultsA memory recovery effect was found to be associated with the reduction of Aβ1–42-induced expression of inflammatory proteins (iNOS, COX-2, GFAP, and Iba-1) and the suppression of CHI3L1 expression in the brain. Additionally, K284-6111 reduced Aβ1–42-induced β-secretase activity and Aβ generation. Lipopolysaccharide (LPS)-induced (1 μg/mL) expression of inflammatory (COX-2, iNOS, GFAP, Iba-1) and amyloidogenic proteins (APP, BACE1) were decreased in microglial BV-2 cells and cultured astrocytes by the K284-6111 treatment (0.5, 1, and 2 μM). Moreover, K284-6111 treatment suppressed p50 and p65 translocation into the nucleus, and phosphorylation of IκB in vivo and in vitro.ConclusionThese results suggest that CHI3L1 inhibitor could be an applicable intervention drug in amyloidogenesis and neuroinflammation, thereby preventing memory dysfunction via inhibition of NF-κB.

Immunomodulation of Host Chitinase 3-Like 1 During a Mammary Pathogenic Escherichia coli Infection.

Chitin is a N-acetyl-d-glucosamine biopolymer that can be recognized by chitin-binding proteins. Although mammals lack chitin synthase, they induce proteins responsible for detecting chitin in response to bacterial infections. Our aim was to investigate whether chitinase 3-like 1 (CHI3L1) has a potential role in the innate immunity of the Escherichia coli (E. coli) infected mammary gland. CHI3L1 protein was found to be secreted in whey of naturally coliform-affected quarters compared to whey samples isolated from healthy udders. In addition, gene expression of CHI3L1 was confirmed in udder tissue of cows experimentally infected with a mammary pathogenic E. coli (MPEC) strain. Despite the known anatomical differences, the bovine udders’ innate immune response was mimicked by applying an experimental mouse model using MPEC or non-MPEC isolates. The effect of CHI3L1 expression in the murine mammary gland in response to coliform bacteria was investigated through the use of CHI3L1−/− mice as well as through treatment with either a pan-caspase inhibitor or chitin particles in wild-type mice. The local induction of CHI3L1 postinfection with different E. coli strains was demonstrated to be independent of both bacterial growth and mammary interleukin (IL)-8 levels. Indeed, CHI3L1 emerged as a regulator impacting on the transcytosis of Ly6G-positive cells from the interstitial space into the alveolar lumen of the mammary tissue. Furthermore, CHI3L1 was found to be upstream regulated by caspase activity and had a major downstream effect on the local pro-inflammatory cytokine profile, including IL-1beta, IL-6, and RANTES/CCL5. In conclusion, CHI3L1 was demonstrated to play a key role in the cytokine and caspase signaling during E. coli triggered inflammation of the mammary gland.

Chitinase 3 like 1 (CHI3L1) promotes vasculogenic mimicry formation in cervical cancer

Vasculogenic mimicry (VM) is an alternative microvascular system which tumour cells orchestrate, independent of endothelial cell-mediated angiogenesis. VM develops tumour vascular networks that correlate with tumour growth, metastasis, and short survival time of patients with a number of cancers. However, little is known regarding VM in the vascularisation of cervical cancer. Chitinase 3 like 1 (CHI3L1) has been previously reported to display the ability to induce angiogenesis in cervical cancer. Here, we explored a pathological role of CHI3L1 in tumour cell-mediated vascularisation. Sixty-six samples of cervical cancer were collected to examine CHI3L1 expression and VM formation using immunohistochemistry and CD34-periodic acid-Schiff (PAS) dual staining. CHI3L1 expression was significantly correlated with formation of tumour cell-associated vascular channels in the absence of endothelial cells (p=0.031). Interestingly, tumour samples lacking VM were positively correlated with non-metastasis (p=0.035). Patients with VM positive tumours tended to have decreased overall survival (OS) compared to those with VM negative samples (43.9 versus 64.6 months, p=0.079). In addition, recombinant CHI3L1 enhanced cervical cancer cell lines to form tube-like structures, supporting the notion that CHI3L1 mediates VM in cervical cancer. Our present data reveal the crucial role of CHI3L1 in the formation of VM, which may contribute to tumour aggressiveness. Therefore, targeting CHI3L1 may be a valuable strategy for the reduction of cervical cancer vascularisation and metastasis.

Preliminary Study on Gene Expression of Chitinase-Like Cytokines in Human Airway Epithelial Cell Under Chitin and Chitosan Microparticles Treatment.

Small-sized chitin and chitosan microparticles (MPs) reduce allergic inflammation. We examined the capacity of these glycans to stimulate A549 human airway epithelial cells to determine the feasibility of using of these glycans as allergic therapeutic modality. A549 cells were treated with MPs and then expressions levels of chitinase domain-containing 1 (CHID1) and chitinase 3-like 1 (CHI3L1) genes were determined by quantitative real-time PCR. IL-6 production was measured by ELISA. Chitin MPs resulted in upregulation of CHI3L1 expression by 35.7-fold while mRNA expression did not change with chitosan MPs. Compared to the untreated group, production of IL-6 was significantly decreased in the chitosan MPs-treated group, but chitin MPs treatment cause elevation of IL-6 level. This study demonstrates that chitin potently induces CHI3L1 expression, but chitosan is relatively inert. This effect and inhibition of pro-inflammatory cytokine (IL-6) suggest that chitosan MPs may possess more potential for therapeutic uses in human airway allergic inflammation.