YKL-40 (cartilage gp-39) induces proliferative events in cultured chondrocytes and synoviocytes and increases glycosaminoglycan synthesis in chondrocytes

YKL-40 in serum: a promising biomarker of juvenile SLE and strongly correlated with disease duration

BACKGROUND

The biological function of YKL-40 is not well determined in different inflammatory and autoimmune diseases; however, some data highlighted its possible connection with disease activity.

AIM

We investigated the diagnostic utility of serum YKL-40 in patients with SLE and examined its correlation with disease activity. Additionally, we examined any differences in serum YKL-40 levels between juvenile and adult SLE patients.

METHODS

We included 78 female patients with SLE and 42 controls. The level of YKL-40 in serum was measured by ELISA.

RESULTS

The serum YKL-40 level in SLE patients was significantly higher compared to the control group (9 (3) ng/mL vs. 5.5 (0.1) ng/mL; p < 0.001). YKL-40 showed excellent diagnostic utility with an AUC of 1 (p < 0.001) and a cutoff point of 5.6, providing sensitivity and specificity of 100%. YKL-40 was higher in adolescents and those with a positive family history of SLE (p = 0.01 for both) and positively correlated with disease duration (r = 0.45, p < 0.001). YKL-40 level was significantly higher in patients with photosensitivity, fever, vasculitis, blood disorders, positive anti-dsDNA, and APL ab (p < 0.05 for all). Conversely, patients with skin manifestations had a significantly lower YKL-40 (p = 0.004). In juvenile SLE, the AUC was 0.65 and a p-value of 0.01, and at a cutoff value of (8.7) ng/mL, the sensitivity and specificity were 72% and 60%, respectively.

CONCLUSION

YKL-40 in serum could be a promising biomarker in patients with SLE, especially in adolescent-onset cases. It is independently influenced by disease duration, anemia, thrombocytopenia, positive anti-dsDNA, and APL ab features.

Strong YKL-40 expression in the invasive tumor front of colorectal cancer-A pilot study

Тhe poor prognosis of patients initially diagnosed at an advanced stage of colorectal cancer (CRC) and the heterogeneity within the same tumor stage define the need for additional predictive biomarkers. Tumor buds are proposed as a poor prognostic factor for CRC, however, they are still not implemented into routine pathology reporting. In turn, the chitinase-3-like protein 1 (CHI3L1) also known as YKL-40, is regarded as a candidate circulating biomarker and therapeutic target in CRC. The aim of our study was to investigate tissue YKL-40 localization and tumor budding in CRC. Thirty-one CRC patients and normal colonic tissues were examined. The correlation between YKL-40 levels, tumor budding and clinocopathological parameters was evaluated by polychoric correlation analysis. The immunohistochemical assessment revealed high YKL-40 expression in CRC in contrast to normal mucosa. Specifically, intense YKL-40 staining was detected in the front of tumor invasion compared with tumor parenchyma and noncancerous tissue. We present novel data for increased YKL-40 expression in tumor buds within the front of tumor invasion. We assume that the combination of this morphological parameter with the tissue level of the pleotropic YKL-40 glycoprotein could serve as a future prognostic biomarker for CRC stratification and treatment.

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.

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.

High chitotriosidase and AGE levels in acromegaly: a case-control study

PURPOSE

Acromegaly is associated with oxidative stress and inflammation parameters. Chitotriosidase (CHITO) is a marker of macrophage activation and plays a pivotal role in the activation of inflammatory and immunological responses. Our study aimed to determine CHITO,YKL-40, advanced glycation end product (AGE), and high-sensitivity C-reactive protein (hsCRP) levels to investigate malondialdehyde (MDA), catalase, superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activities and to evaluate any association of these parameters with carotid intima media thickness (cIMT) in patients with controlled acromegaly.

METHODS

Thirty controlled acromegaly patients and 41 age- and sex-matched control cases were studied. We obtained demographic data, hormonal and metabolic parameters, and cIMT. CHITO activity was measured with the fluorometric method of Chamoles et al. YKL-40 and hsCRP levels were measured using ELISA. AGEs were measured based on spectrofluorimetric detection. GSH-Px activity was determined by a colorimetric assay. MDA, SOD, and catalase activities were determined in hemolysis.

RESULTS

Higher CHITO, AGE, and hsCRP concentrations were observed in patients with acromegaly compared to controls. SOD levels were non-significantly higher in the acromegaly group, while catalase activities were lower in patients with acromegaly. Correlation analyses of CHITO, AGEs, YKL-40, hsCRP, MDA, catalase, GSH-Px, and SOD with metabolic, anthropometric, and laboratory parameters did not demonstrate any significant correlation (p > 0.05). There was no significant difference between groups with regard to cIMT levels.

CONCLUSION

This is the first study investigating CHITO and AGE levels in patients with acromegaly. Serum CHITO, AGE, and hsCRP levels in acromegalic patients were significantly increased. It may be important to evaluate CHITO, AGE, and hsCRP levels in acromegalic patients who are already under cardiometabolic surveillance due to risk of developing cardiovascular disease.

Potential role of chitinase-3-like protein 1 (CHI3L1/YKL-40) in neurodegeneration and Alzheimer's disease

Chitinase-3-like protein 1 (CHI3L1/YKL-40) has long been known as a biomarker for early detection of neuroinflammation and disease diagnosis of Alzheimer's disease (AD). In the brain, CHI3L1 is primarily provided by astrocytes and heralds the reactive, neurotoxic state triggered by inflammation and other stress signals. However, how CHI3L1 acts in neuroinflammation or how it contributes to AD and relevant neurodegenerative conditions remains unknown. In peripheral tissues, our group and others have uncovered that CHI3L1 is a master regulator for a wide range of injury and repair events, including the innate immunity pathway that resembles the neuroinflammation process governed by microglia and astrocytes. Based on assessment of current knowledge regarding CHI3L1 biology, we hypothesize that CHI3L1 functions as a signaling molecule mediating distinct neuroinflammatory responses in brain cells and misfunctions to precipitate neurodegeneration. We also recommend future research directions to validate such assertions for better understanding of disease mechanisms.

YKL-40 protein expression in human tumor samples and human tumor cell line xenografts: implications for its use in tumor models

BACKGROUND

YKL-40, also known as non-enzymatic chitinase-3 like-protein-1 (CHI3L1), is a glycoprotein expressed and secreted mainly by inflammatory cells and tumor cells. Accordingly, several studies demonstrated elevated YKL-40 serum levels in cancer patients and found YKL-40 to be correlated with a poor prognosis and disease severity in some tumor entities. YKL-40 was suggested to be involved in angiogenesis and extracellular matrix remodeling. As yet, however, its precise biological function remains elusive.

METHODS

As YKL-40 protein expression has only been investigated in few malignancies, we employed immunohistochemical detection in a large multi-tumor tissue microarray consisting of 2,310 samples from 72 different tumor entities. In addition, YKL-40 protein expression was determined in primary mouse xenograft tumors derived from human cancer cell lines.

RESULTS

YKL-40 could be detected in almost all cancer entities and was differently expressed depending on tumor stage and subtype (e.g., thyroid cancer, colorectal cancer, gastric cancer and ovarian cancer). While YKL-40 was absent in in vitro grown human cancer cell lines, YKL-40 expression was upregulated in xenograft tumor tissues in vivo.

CONCLUSIONS

These data provide new insights into YKL-40 expression at the protein level in various tumor entities and its regulation in tumor models. Our data suggest that upregulation of YKL-40 expression is a common feature in vivo and is finely regulated by tumor cell-microenvironment interactions.

High YKL-40 serum levels and its expression in the muscle tissues of patients with antisynthetase syndrome

BACKGROUND

The protein chitinase-3-like-1 (YKL-40) is rarely analyzed in patients with myositis. Therefore, we aimed to evaluate YKL-40 serum levels; correlate them with laboratory and clinical parameters, disease status, and treatment schemes; and analyze the YKL-40 expression in the muscle tissues of patients with antisynthetase syndrome (ASSD).

METHODS

This cross-sectional single-center study included 64 adult patients with ASSD who were age-, gender-, and ethnicity-matched to 64 healthy control individuals. Their YKL-40 serum levels were analyzed using the Enzyme-Linked Immunosorbent Assay (ELISA) kit method, while YKL-40 expression in muscle tissues was analyzed using an immunohistochemical technique. Disease status was assessed using the International Myositis Assessment and Clinical Studies Group (IMACS) set scores.

RESULTS

The patients' mean age was 44.8 ± 11.8 years, and median disease duration was 1.5 (0.0-4.0) years. These patients were predominantly female (82.8%) and Caucasian (73.4%). Most patients had stable disease. The median YKL-40 serum level was significantly higher in patients with ASSD when compared to the healthy individuals: 538.4 (363.4-853.1) pg/mL versus 270.0 (201.8-451.9) pg/mL, respectively; P < 0.001. However, YKL-40 serum levels did not correlate with any clinical, laboratory, disease status, or therapeutic parameters (P > 0.050), except tumor necrosis factor alpha (TNF-α) serum levels (Spearman's correlation, rho = 0.382; P = 0.007). YKL-40 was highly expressed by inflammatory cells found in muscle biopsy specimens.

CONCLUSIONS

High YKL-40 serum levels were observed in patients with ASSD and correlated positively with TNF-α serum levels. Moreover, YKL-40 was expressed by the inflammatory cells of the muscle tissue.

Relevance of Plasma Matrix Metalloproteinase-9 for Bronchiolitis Obliterans Syndrome after Allogeneic Hematopoietic Cell Transplantation

Bronchiolitis obliterans syndrome (BOS) is a highly morbid form of chronic graft-versus-host disease (GVHD) after allogeneic hematopoietic cell transplantation (HCT). Several plasma proteins have been identified as biomarkers for BOS after lung transplantation. The relevance of these biomarkers in BOS patients after allogeneic HCT has not been examined. We hypothesized that biomarkers associated with BOS after lung transplantation are also associated with BOS after allogeneic HCT. We tested plasma samples from 33 adult HCT patients who participated in a phase II multicenter study of fluticasone, azithromycin, and montelukast (FAM) treatment for new-onset BOS (NCT01307462), and matched control samples of HCT patients who had non-BOS chronic GVHD (n = 31) and those who never experienced chronic GVHD (n = 29) (NCT00637689 and NCT01902576). Candidate biomarkers included matrix metalloproteinase-9 (MMP-9), MMP-3, and chitinase-3-like-1 glycoprotein (YKL-40). MMP-9 concentrations were higher in the patients with BOS compared with those with non-BOS chronic GVHD (P = .04) or no chronic GVHD (P < .001). MMP-3 concentrations were higher in patients with BOS (P < .001) or non-BOS chronic GVHD (P < .001) compared with those with no chronic GVHD. YKL-40 concentrations did not differ statistically among the 3 groups. MMP-9 concentrations before starting FAM therapy were higher in patients who experienced treatment failure within 6 months compared with those with treatment success (P = .006), whereas MMP-3 or YKL-40 concentrations did not differ statistically between these 2 groups. Patients with an MMP-9 concentration ≥200,000 pg/mL before starting FAM therapy had worse overall survival compared with those with lower MMP-9 concentrations. Our data suggest that plasma MMP-9 concentration could serve as a relevant biomarker at diagnosis of BOS after allogeneic HCT for prognostication of survival and for prediction of treatment response. Further validation is needed to confirm our findings.

LncRNA KCNQ1OT1 Promotes Proliferation, Invasion and Metastasis of Prostate Cancer by Regulating miR-211-5p/CHI3L1 Pathway

Background

Bone metastasis after failure of castration therapy is the main reason of death in patients with prostate cancer (PCa). Therefore, full awareness of the metastasis mechanism of PCa and discovery of new therapeutic targets are necessary. Studies showed that lncRNA was involved in the development of cancer. However, its potential role and molecular mechanism in PCa metastasis are still unclear. YKL-40 is an 18 glycosyl hydrolase family protein encoded by CHI3L1, which is involved in the invasion and metastasis of various tumors. A previous study of the authors found that YKL-40 was related to the invasion and metastasis of PCa cells. However, the cause of its abnormal expression in PCa remains unclear. The present study explored the role of lncRNA KCNQ1OT1/miR-211-5p/CHI3L1 regulatory axis in the proliferation, invasion, and metastasis of PCa.

Methods

RT-PCR and Western blot were used to measure the expression profiles of KCNQ1OT1 and YKL. CCK-8 and Transwell assays were used to examine their effects on cell proliferation and migration. Double luciferase reporter assay was used to verify the interactions between miR-211-5p and CHI3L1 3′-UTR.

Results

KCNQ1OT1 expression was upregulated in PCa tissues and cells. Downregulating this expression inhibited PCa cell invasion, proliferation, and metastasis. KCNQ1OT1 bound miR-211-5p competitively, and miR-211-5p targeted CHI3L1 3′-UTR. miR-211-5p expression was downregulated, whereas CHI3L1 (YKL-40) expression was upregulated. miR-211-5p levels were negatively correlated with KCNQ1OT1 expression and CHI3L1 mRNA. The decrease in YKL-40 expression in PCa cells induced by the downregulation of KCNQ1OT1 expression could be offset by miR-211-5p inhibitor transfection.

Conclusion

This study showed that lncRNA KCNQ1OT1, as a ceRNA, upregulated CHI3L1 and promoted PCa progression through competitive binding to miR-211-5p.

Chitinase-3 like-protein-1 function and its role in diseases

Non-enzymatic chitinase-3 like-protein-1 (CHI3L1) belongs to glycoside hydrolase family 18. It binds to chitin, heparin, and hyaluronic acid, and is regulated by extracellular matrix changes, cytokines, growth factors, drugs, and stress. CHI3L1 is synthesized and secreted by a multitude of cells including macrophages, neutrophils, synoviocytes, chondrocytes, fibroblast-like cells, smooth muscle cells, and tumor cells. It plays a major role in tissue injury, inflammation, tissue repair, and remodeling responses. CHI3L1 has been strongly associated with diseases including asthma, arthritis, sepsis, diabetes, liver fibrosis, and coronary artery disease. Moreover, following its initial identification in the culture supernatant of the MG63 osteosarcoma cell line, CHI3L1 has been shown to be overexpressed in a wealth of both human cancers and animal tumor models. To date, interleukin-13 receptor subunit alpha-2, transmembrane protein 219, galectin-3, chemo-attractant receptor-homologous 2, and CD44 have been identified as CHI3L1 receptors. CHI3L1 signaling plays a critical role in cancer cell growth, proliferation, invasion, metastasis, angiogenesis, activation of tumor-associated macrophages, and Th2 polarization of CD4⁺ T cells. Interestingly, CHI3L1-based targeted therapy has been increasingly applied to the treatment of tumors including glioma and colon cancer as well as rheumatoid arthritis. This review summarizes the potential roles and mechanisms of CHI3L1 in oncogenesis and disease pathogenesis, then posits investigational strategies for targeted therapies.

Circulating lung biomarkers in idiopathic lung fibrosis and interstitial lung diseases associated with connective tissue diseases: Where do we stand?

Interstitial lung diseases (ILDs) are complex diseases with various courses where personalized medicine is highly expected. Biomarkers are indicators of physiological, pathological processes or of pharmacological response to therapeutic interventions. They can be used for diagnosis, risk-stratification, prediction and monitoring of treatment response. To better delineate the input and pitfalls of biomarkers in ILDs, we performed a systematic review and meta-analysis of literature in MEDLINE and Embase databases from January 1960 to February 2019. We focused on circulating biomarkers as having the highest generalizability. Overall, 70 studies were included in the review and 20 studies could be included in the meta-analysis. This review highlights that ILD associated with connective tissue diseases (CTD-ILD) and idiopathic pulmonary fibrosis (IPF) share common biomarkers, suggesting common pathophysiological pathways. KL-6 and SP-D, could diagnose lung fibrosis in both IPF and CTD-ILD, with KL-6 having the strongest value (OR: 520.95[110.07-2465.58], p<0.001 in IPF and OR:26.43[7.15-97.68], p<0.001 in CTD-ILD), followed by SPD (OR: 33.81[3.20-357.52], p = 0.003 in IPF and 13.24 [3.84-45.71] in SSc-ILD), MMP7 appeared as interesting for IPF diagnosis (p<0.001), whereas in SSc, CCL18 was associated with ILD diagnosis. Both CCL18 and KL-6 were predictive for the outcomes of ILDs, with higher predictive values for CCL18 in both IPF (OR:10.22[4.72-22.16], p<0.001 and in SSc [2.62[1.71-4.03], p<0.001). However, disease specific biomarkers are lacking and large longitudinal studies are needed before the translational use of the potential biomarkers in clinical practice. With the recent availability of new effective therapies in ILDs, further studies should assess response to treatment.

The functional difference of eight chitinase genes between male and female of the cotton mealybug, Phenacoccus solenopsis

The cotton mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) is a polyphagous insect that attacks tens of plant and causes substantial economic loss. Insect chitinases are required to remove the old cuticle to allow for continued growth and development. Though insect chitinases have been well studied in tens of insects, their functions in mealybug are still not addressed. Here, we sequenced the transcriptomes of adult males and females, from which eight chitinase genes were identified. We then used the method of rapid amplification of cDNA ends to amplify their full length. Phylogenetic analysis indicated that these genes clustered into five subgroups. Among which, group II PsCht2 had the longest transcript and was highly expressed at second instar nymph. PsCht10, PsCht3-3 and PsIDGF were highly expressed in the adult females, whereas PsCht4 and PsCht4-1 were significantly expressed at the male pupa and adult male. Next, we knocked down all eight chitinase genes by feeding the double-stranded RNA. Knockdown of PsCht4 or PsCht4-1 led to the failure of moult and, silencing PsCht5 resulted in pupation defect, while silencing PsCht10 led to small body size, suggesting these genes have essential roles in development and can be used as a potential target for pest control.

Identification of Chitinase-3-Like Protein 1 as a Novel Neutrophil Antigenic Target in Crohn's Disease

BACKGROUND AND AIMS

There is an increasing incidence of inflammatory bowel disease [IBD]. Autoimmune responses are involved in the pathophysiology of IBD, but their underlying pathways and target antigens have not yet been fully elucidated.

METHODS

Autoantigenic targets in IBD were identified after separation of whole cell proteins isolated from neutrophils using two-dimensional electrophoresis and matrix assisted laser desorption ionization - time of flight mass spectrometry-based protein identification of the spots that displayed Western blotting signals with anti-neutrophil cytoplasmic antibody-positive sera. The prevalence of IgG, IgA and secretory IgA [sIgA] to chitinase 3-like protein 1 [CHI3L1] was analysed by enzyme-linked immunosorbent assays using recombinant CHI3L1 in 110 patients with Crohn's disease [CD], 95 with ulcerative colitis [UC], 126 with coeliac disease [CeD] and 86 healthy controls [HCs].

RESULTS

The 18-glycosylhydrolase family member CHI3L1 was identified as a neutrophil autoantigenic target. CD patients displayed significantly higher levels of IgG to CHI3L1 than patients with UC and CeD (p < 0.0001, respectively). IgA and sIgA to CHI3L1 was significantly higher in CD than in UC, CeD and HCs [p < 0.0001, respectively]. IgA and sIgA to CHI3L1 demonstrated the highest prevalence in CD [25.5%, 28/110; and 41.8%%, 46/110] compared to HCs [2.3%, 2/86; and 4.7%%, 4/86; p = 0.0015 and p < 0.0001] and are associated with a more complicated progression of CD.

CONCLUSION

CHI3L1 is a novel neutrophil autoantigenic target in CD. IgA and sIgA to CHI3L1 may serve as novel markers for CD and may facilitate the serological diagnosis of IBD.

Concentration of Chondrogenic Soluble Factors in Freshly Harvested Lipoaspirate

BACKGROUND

Cartilage tissue has a limited capacity for healing with the consequence that patients are often treated symptomatically until they become candidates for osteotomy or total joint replacement. Alternative biological therapies, for example, application of platelet-rich plasma and implantation of chondrocytes and mesenchymal stem cells, have emerged as a new treatment modality to repair articular cartilage. In addition, autologous fat transfer is performed for treatment of cartilage defects, example given, in osteoarthrosis, but several questions regarding basic biochemical properties of the transplant remain unanswered. Bone morphogenetic protein 4 (BMP4), matrix metalloproteinase (MMP)-8, cartilage oligomeric matrix protein (COMP), and chitinase-3-like protein 1 (CHI3L1) have been shown to be involved in chondrogenic regeneration and represent potential therapeutic agents for cartilage repair. However, no study regarding naturally occurring levels of these soluble factors in transplanted adipose tissue has yet been performed.

METHODS

To investigate the influence of age, body mass index, donor site, and sex on the concentration of BMP4, MMP-8, COMP, and CHI3L1 in freshly aspirated adipose tissue, their content was measured by means of enzyme-linked immunosorbent assay readings.

RESULTS

There were significant quantities of BMP4, MMP-8, COMP, and CHI3L1 (23.6, 249.9, 298.0, and 540.6 pg/mg, respectively) in the lipoaspirate harvested for transplantation. There was no correlation between the content of soluble factors and the patients' age or body mass index. Furthermore, the sex did not affect the amount of the investigated factors. However, there were significantly lower contents of BMP4, COMP, and CHI3L1 found in lipoaspirates harvested from the abdomen compared with nonabdominal donor sites.

CONCLUSIONS

Naturally occurring differences in the concentrations of the investigated soluble factors will favor certain donor sites for autologous fat transfer in the field of cartilage repair. Thus, increasing knowledge will enable researchers and clinicians to make autologous fat transfer procedures more reliable and efficient for treatment of articular cartilage defects.

YKL-40 as a Potential Biomarker and a Possible Target in Therapeutic Strategies of Alzheimer's Disease

Background:

Growing body of evidence suggests that the pathogenesis of Alzheimer’s disease (AD), a progressing neurodegenerative condition, is not limited to the neuronal compartment, but also involves various immunological mechanisms. Insoluble Aβ aggregates in the brain can induce the activation of microglia, resulting in the synthesis of proinflammatory mediators, which further can stimulate astrocytic expression of YKL-40. Therefore, the aim of the current review is to present up-to-date data about the role of YKL-40 as a biomarker of AD as well as the possibility of therapeutic strategies targeting neuroinflammation.

Objective/Methods:

We searched PubMed articles for the terms “YKL-40”, “neurodegeneration”, “neuroinflammation” and “Alzheimer’s disease”, and included papers focusing on this review’s scope.

Results:

Recent studies indicate that CSF concentrations of YKL-40 were significantly higher in AD patients than in cognitively normal individuals and correlated with dementia biomarkers, such as tau proteins and amyloid beta. Determination of YKL-40 CSF concentration may be also helpful in differentiation between types of dementia and in the distinction of patients in the stable phase of MCI from those who progressed to dementia. Moreover, significantly increased levels of YKL-40 mRNA were found in AD brains in comparison with non-demented controls. Additionally, it was suggested that anti-inflammatory treatment might relief the symptoms of AD and slow its progression.

Conclusion:

Based on the recent knowledge, YKL-40 might be useful as a possible biomarker in the diagnosis and prognosis of AD. Modulation of risk factors and targeting of immune mechanisms, including systemic inflammation could lead to future preventive or therapeutic strategies for AD.

Serum YKL-40 as a biomarker for liver fibrosis in chronic hepatitis B patients with normal and mildly elevated ALT

Purpose

YKL-40 is a chitinase-like protein expressed in multiple tissues including liver and is reported as a fibrosis marker. This study aimed to determine whether YKL-40 could serve as a diagnostic marker for the assessment of liver fibrosis in chronic hepatitis B patients with normal and mildly elevated ALT.

Methods

Six hundred and eighty-five patients with chronic hepatitis B infection were enrolled in this study from October 2013 to March 2016. All patients underwent liver biopsy and then staged based on Ishak histological system. Serum YKL-40 levels were measured by Human Magnetic Luminex Assays.

Results

Among chronic hepatitis B patients with normal and mildly elevated ALT, almost more than 30% of patients have significant liver fibrosis. Serum YKL-40 levels increased significantly in parallel with the progression of fibrosis in patients with ALT less than two times the upper limit of normal range (P < 0.0001). Multivariate analysis revealed that serum YKL-40, hyaluronic acid, PLT, and AST were independently associated with significant fibrosis. We established a novel YKL-40-based fibrosis model for patients with ALT less than two times the upper limit of normal range (ULN). YKL-40 model was superior to APRI, FIB-4, Forns’ index, and Hui model for diagnosis of significant fibrosis in patients with ALT < 2ULN, with AUROCs of 0.786 [95% confidence interval (CI) 0.726–0.846] in the training group, 0.831 (95%CI 0.752–0.910) in the validation group and 0.801 (95%CI 0.753–0.849) in the entire cohort.

Conclusion

Serum YKL-40 is a feasible biomarker of liver fibrosis in chronic hepatitis B patients. YKL-40 model was superior to APRI, FIB-4, Forns’ index and Hui model for diagnosis of significant fibrosis in patients with normal and mildly elevated ALT.

Electronic supplementary material

The online version of this article (10.1007/s15010-018-1136-2) contains supplementary material, which is available to authorized users.

TrkB-containing exosomes promote the transfer of glioblastoma aggressiveness to YKL-40-inactivated glioblastoma cells

The neurotrophin receptors are known to promote growth and proliferation of glioblastoma cells. Their functions in spreading glioblastoma cell aggressiveness to the microenvironment through exosome release from glioblastoma cells are unknown. Considering previous reports demonstrating that YKL-40 expression is associated with undifferentiated glioblastoma cancer stem cells, we used YKL-40-silenced cells to modulate the U87-MG differentiated state and their biological aggressiveness. Herein, we demonstrated a relationship between neurotrophin-receptors and YKL-40 expression in undifferentiated cells. Differential functions of cells and derived-exosomes were evidenced according to neurotrophin receptor content and differentiated cell state by comparison with control pLKO cells. YKL-40 silencing of glioblastoma cells impairs proliferation, neurosphere formation, and their ability to induce endothelial cell (HBMEC) migration. The modulation of differentiated cell state in YKL-40-silenced cells induces a decrease of TrkB, sortilin and p75NTR cellular expressions, associated with a low-aggressiveness phenotype. Interestingly, TrkB expressed in exosomes derived from control cells was undetectable in exosomes from YKL-40 -silenced cells. The transfer of TrkB-containing exosomes in YKL-40-silenced cells contributed to restore cell proliferation and promote endothelial cell activation. Interestingly, in U87 MG xenografted mice, TrkB-depleted exosomes from YKL-40-silenced cells inhibited tumor growth in vivo. These data highlight that TrkB-containing exosomes play a key role in the control of glioblastoma progression and aggressiveness. Furthermore, TrkB expression was detected in exosomes isolated from plasma of glioblastoma patients, suggesting that this receptor may be considered as a new biomarker for glioblastoma diagnosis.

Chitinase-like proteins as regulators of innate immunity and tissue repair: helpful lessons for asthma?

Chitinases and chitinase-like proteins (CLPs) belong to the glycoside hydrolase family 18 of proteins. Chitinases are expressed in mammals and lower organisms, facilitate chitin degradation, and hence act as host-defence enzymes. Gene duplication and loss-of-function mutations of enzymatically active chitinases have resulted in the expression of a diverse range of CLPs across different species. CLPs are genes that are increasingly associated with inflammation and tissue remodelling not only in mammals but also across distant species. While the focus has remained on understanding the functions and expression patterns of CLPs during disease in humans, studies in mouse and lower organisms have revealed important and overlapping roles of the CLP family during physiology, host defence and pathology. This review will summarise recent insights into the regulatory functions of CLPs on innate immune pathways and discuss how these effects are not only important for host defence and tissue injury/repair after pathogen invasion, but also how they have extensive implications for pathological processes involved in diseases such as asthma.

YKL-40 expression in abnormal invasive placenta cases

OBJECTIVE

YKL-40 is a secreted glycoprotein and has been implicated in the proliferation and differentiation of malignant cells, extracellular tissue remodelling, neovascularisation, inhibition of cancer cell apoptosis and stimulation of tumour-associated fibroblasts. The purpose of this study was to evaluate YKL-40 tissue expression in extravillous trophoblast invasion and its possible implication in placenta creta.

METHODS

A total of 35 placenta creta cases and six control cases were included in the study, of which eight cases were placenta accreta, 12 were increta and 15 were percreta. Histological YKL-40 staining was scored in tissue as weak (1), medium (2) and strong (3).

RESULTS

YKL-40 immunoreactivity intensity in the percreta group was significantly higher compared to the increta and accreta groups (2.47±0.74, 1.33±0.49 and 1.37±0.52, respectively; P=0.000). YKL-40 immunoreactivity intensity was positively correlated with creta (r=0.6; P=0.000), depth of invasion (r=0.49; P=0.003) and depth of invasion to full thickness ratio (r=0.58; P=0.000).

CONCLUSION

This study demonstrated that YKL-40 is strongly expressed in placenta percreta and is correlated with extravillous trophoblast invasion. These findings may be informative for understanding the pathophysiology of placenta creta.

Clinical Utility of YKL-40 in Polymyositis/dermatomyositis-associated Interstitial Lung Disease

Objective.

Interstitial lung disease (ILD) is involved in polymyositis/dermatomyositis (PM/DM), a disease associated with poor prognoses. Chitinase-3-like-1 protein (YKL-40) has pleiotropic biological activities involved in inflammation, cell proliferation, and tissue remodeling; however, the clinical application of YKL-40 remains limited. We investigated the clinical significance of YKL-40 in PM/DM–ILD.

Methods.

Sixty-nine consecutive patients with PM/DM–ILD and 34 healthy controls were analyzed. We measured baseline and followup serum YKL-40 using an ELISA, evaluated the association of YKL-40 with clinical variables and survival, and examined YKL-40 expression in lung specimens from patients with PM/DM–ILD using immunohistochemistry.

Results.

Serum YKL-40 levels were significantly greater in patients with PM/DM–ILD compared with healthy controls (p < 0.0001). Serum YKL-40 was correlated with arterial oxygen pressure (r = –0.40, p < 0.001) and percent-predicted DLCO (r = –0.41, p = 0.01) in patients with PM/DM–ILD. Multivariate Cox hazard analysis demonstrated that higher serum YKL-40 and lower percent-predicted forced vital capacity were independently associated with a poor prognosis. Immunohistochemistry analysis demonstrated that YKL-40 expression was enhanced in aggregated intraalveolar macrophages and hyperproliferative alveolar epithelial cells in patients with PM/DM–ILD.

Conclusion.

YKL-40 is a promising biomarker for evaluating PM/DM–ILD activity/severity and predicting disease prognosis. Insights into YKL-40 might help elucidate the pathogenesis of PM/DM–ILD.

New Insights Into the Relationship Between Chitinase-3-Like-1 and Asthma

PURPOSE OF REVIEW

CHI3L1 (also known as YKL-40), a member of "mammalian chitinase-like proteins," is a serum protein lacking enzymatic activity. Although the protein is highly conserved in mammals, a consensus regarding its role in human pathologies is currently lacking. In an attempt to shed light on the many physiological functions of the protein, specifically with regard to asthma, a comprehensive overview of recent studies is provided.

RECENT FINDINGS

In asthma, CHI3L1 is secreted from macrophages and airway epithelial cells through an IL-13 related mechanism. Th2-associated inflammatory responses due to allergen exposure, resulting in airway hyper-responsiveness and smooth muscle contraction, play a role in tissue remodeling. The importance of CHI3L1 in initiation and development of asthma is not limited to its involvement in highly orchestrated events of inflammatory cytokines but further research is needed for further elucidation. Levels of the protein are associated with severity for numerous pathologies, including asthma, suggesting limited specificity as a biomarker.

YKL-40-Induced Inhibition of miR-590-3p Promotes Interleukin-18 Expression and Angiogenesis of Endothelial Progenitor Cells

YKL-40, also known as human cartilage glycoprotein-39 or chitinase-3-like-1, is a pro-inflammatory protein that is highly expressed in rheumatoid arthritis (RA) patients. Angiogenesis is a critical step in the pathogenesis of RA, promoting the infiltration of inflammatory cells into joints and providing oxygen and nutrients to RA pannus. In this study, we examined the effects of YKL-40 in the production of the pro-inflammatory cytokine interleukin-18 (IL-18), and the stimulation of angiogenesis and accumulation of osteoblasts. We observed that YKL-40 induces IL-18 production in osteoblasts and thereby stimulates angiogenesis of endothelial progenitor cells (EPCs). We found that this process occurs through the suppression of miR-590-3p via the focal adhesion kinase (FAK)/PI3K/Akt signaling pathway. YKL-40 inhibition reduced angiogenesis in in vivo models of angiogenesis: the chick embryo chorioallantoic membrane (CAM) and Matrigel plug models. We report that YKL-40 stimulates IL-18 expression in osteoblasts and facilitates EPC angiogenesis.

Review of Prospects of Biological Fluid Biomarkers in Osteoarthritis

Osteoarthritis (OA) is a degenerative disease of the joints and is one of the leading causes of disability in adults. However, there are no key therapeutics for OA and medical treatment is based on managing the symptoms and slowing down progression of the disease. Diagnostics based on clinical examination and radiography have provided little information about metabolic changes in joint tissues, disease onset and progression. Due to lack of effective methods for early detection and evaluation of treatment outcome, the measurement of biochemical markers (biomarkers) shows promise as a prospective method aiding in disease monitoring. OA biomarkers that are present in biological fluids such as blood, urine and synovial fluid, sources that are easily isolated from body, are of particular interest. Moreover, there are increasingly more studies identifying and developing new biomarkers for OA. In this review, efforts have been made to summarize the biomarkers that have been reported in recent studies on patients. We also tried to classify biomarkers according to tissue metabolism (bone, cartilage and synovial metabolism markers), pathological pathways (inflammatory and genetic markers) and biological function (chemokines, growth factors, acute phase proteins, etc.).

A network-based pathway-expanding approach for pathway analysis

Background

Pathway analysis combining multiple types of high-throughput data, such as genomics and proteomics, has become the first choice to gain insights into the pathogenesis of complex diseases. Currently, several pathway analysis methods have been developed to study complex diseases. However, these methods did not take into account the interaction between internal and external genes of the pathway and between pathways. Hence, these approaches still face some challenges. Here, we propose a network-based pathway-expanding approach that takes the topological structures of biological networks into account.

Results

First, two weighted gene-gene interaction networks (tumor and normal) are constructed integrating protein-protein interaction(PPI) information, gene expression data and pathway databases. Then, they are used to identify significant pathways through testing the difference of topological structures of expanded pathways in the two weighted networks. The proposed method is employed to analyze two breast cancer data. As a result, the top 15 pathways identified using the proposed method are supported by biological knowledge from the published literatures and other methods. In addition, the proposed method is also compared with other methods, such as GSEA and SPIA, and estimated using the classification performance of the top 15 expanded pathways.

Conclusions

A novel network-based pathway-expanding approach is proposed to avoid the limitations of existing pathway analysis approaches. Experimental results indicate that the proposed method can accurately and reliably identify significant pathways which are related to the corresponding disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s12859-016-1333-x) contains supplementary material, which is available to authorized users.

Cholesterol Tethered Poly(DL-Lactic Acid) for Promoting Osteoblast Attachment and Growth

In poly(DL-lactic acid)-cholesterol oligomers (LC), a novel cholesterol modified poly(DL-lactic acid) (PLA), was synthesized via bulk polymerization of DL-lactide using cholesterol initiator. Gel permeation chromatography (GPC) and 1H nuclear magnetic resonance spectroscopy (1H-NMR) results indicated a narrow molecular weight distribution of poly (DL-lactic acid)-cholesterol oligomers (LC). Mouse MC3T3 osteoblast-like cells were selected as a model system to test the cell behavior of cholesterol modified PLA substrates. The osteoblast attachment, proliferation, and viability revealed that the cholesterol modified PLA was significantly osteoblast compatible and may have potential as a bone tissue engineering material.

Role of inflammatory marker YKL-40 in the diagnosis, prognosis and cause of cardiovascular and liver diseases

This review summarizes present evidence for the role of YKL-40 in the diagnosis, prognosis and cause of cardiovascular and alcoholic liver disease. The question of whether YKL-40 is merely a marker or a causal factor in the development of cardiovascular and liver disease is addressed, with emphasis on the Mendelian randomization design. The Mendelian randomization approach uses genetic variants associated with lifelong high plasma YKL-40 levels that are largely unconfounded and not prone to reverse causation. Thus, the approach mimics a controlled double-blind randomized trial, but it uses genetic variants rather than a drug and placebo, and like a blinded trial, it allows inference about causality. Moreover, the review also covers background on the molecular biology and functions of YKL-40, YKL-40 levels in healthy individuals and reference range, and the role of YKL-40 as a biomarker of cardiovascular and alcoholic liver disease. YKL-40 is a plasma protein named after its three N-terminal amino acids, Y (tyrosine), K (lysine) and L (leucine), and its molecular weight of 40 kDa. It is produced by local inflammatory cells in inflamed tissues, such as lipid-laden macrophages inside the vessel wall and perhaps also hepatic stellate cells. Observational studies show that plasma YKL-40 levels are elevated in patients with cardiovascular and liver disease and are associated with disease severity and prognosis. Furthermore, elevated plasma YKL-40 levels in apparently healthy individuals are associated with a 2-fold increased risk of future ischemic stroke and venous thromboembolism, but not with myocardial infarction, suggesting that YKL-40 could play a role in the formation of embolisms rather than atherosclerosis per se. Further, elevated YKL-40 levels combined with excessive alcohol consumption are associated with 10-years risk of alcoholic liver cirrhosis of up to 7%, suggesting that YKL-40 can be used as a strong noninvasive marker of predicting alcoholic liver cirrhosis. Importantly, in Mendelian randomization studies, genetically elevated plasma YKL-40 levels were not associated with risk of cardiovascular and alcoholic liver disease, thus suggesting that plasma YKL-40 does not play a causal role in the development of these diseases. Despite this, plasma YKL-40 levels may play a role in disease progression after diagnosis, and inhibition of YKL-40 activity might be a novel therapy in some cardiovascular and liver diseases.

YKL-40 expression in chronic obstructive pulmonary disease: relation to acute exacerbations and airway remodeling

BACKGROUND

Recent studies suggest that YKL-40, also called chitinase-3-like-1 protein, has been implicated in the pathogenesis of various inflammatory diseases. It is currently unknown, however, whether YKL-40 plays a role in acute exacerbations of chronic obstructive pulmonary disease (AECOPD) and airway remodeling.

METHODS

We evaluated serum YKL-40 levels in patients with AECOPD (n = 37) and stable COPD (n = 44), as well as in controls (n = 47). The association between YKL-40 expression and airway remodeling was analyzed. The effects of YKL-40 on collagen synthesis of primary human lung fibroblasts were also evaluated.

RESULTS

Serum YKL-40 levels were elevated at AECOPD onset as compared to stable disease (median [interquartile range], 78.6 [52.3-122.2] ng/ml versus 46.7 [31.2-75.5] ng/ml; p = 0.0005). The ideal cutoff point for distinguishing patients with AECOPD from those with stable COPD was 64.7 ng/ml (AUC: 0.71; 95%CI: 0.596 to 0.823). YKL-40 expression correlated with airflow obstruction, C-reactive protein, and collagen deposition. Stimulation with YKL-40 promoted collagen production in lung fibroblasts through ERK- and p38-dependent mechanisms.

CONCLUSIONS

YKL-40 expression is up-regulated in patients with COPD and correlates with exacerbation attacks and may contribute to airway remodeling by acting on lung fibroblasts. The current data may provide insight into the underlying pathogenesis of COPD, in which YKL-40 has an important pathogenic role.

TRIAL REGISTRATION

ChiCTR-OCC-13003567.

YKL-40/chitinase-3-like protein 1 is associated with poor prognosis and promotes cell growth and migration of cholangiocarcinoma

YKL-40, a chitinase-like glycoprotein, is expressed at a high level in cancer patients. Its exact function is unknown and is the subject of current investigation. Here, we report the correlation of plasma YKL-40 levels with clinicopathological features of cholangiocarcinoma (CCA), a lethal bile duct cancer, particularly prevalent in Northeastern Thailand. Statistical analysis of plasma YKL-40 concentrations in 57 CCA patients and 41 normal healthy subjects gave a median value of 169.5 ng/mL for CCA patients compared with 46.9 ng/mL for the control subjects (P < 0.0001). There was no significant association of plasma YKL-40 levels with patient age, tumor grade, or histology type. However, Kaplan-Meier analysis suggested that the elevated plasma YKL-40 level was particularly associated with short survival in CCA patients (P = 0.038). Immunohistochemical examination of 34 CCA tissues revealed low expression of YKL-40 in CCA cells, but high expression in adjacent intratumoral stroma, liver, and connective tissues. Univariate analysis showed significant association of the intratumoral YKL-40 expression in CCA tissues with the non-papillary type CCA. Addition of rYKL-40 in the culture medium and transient expression of YKL-40 in CCA cell lines were shown to promote the growth and migration of the tumor cells, and that YKL-40 interacted with a cell-surface receptor involved in the Akt/Erk-mediated pathway. In conclusion, our results support the proposal of YKL-40 as a new candidate prognostic biomarker for cancer diseases.

YKL-40 level in gingival crevicular fluid from patients with periodontitis and type 2 diabetes

OBJECTIVE

YKL-40 is a chitin-binding glycoprotein, the level of which increases in inflammatory diseases, diabetes mellitus (DM), cardiovascular diseases, and tumors. Gingival crevicular fluid (GCF) contains many proteins and markers of periodontitis. The purpose of this study was to investigate YKL-40 level in GCF from patients with periodontitis and DM and the association between YKL-40 level and chronic periodontitis (CP) or DM.

SUBJECTS AND METHODS

The subjects were 121 patients with DM, CP, DM and periodontitis (DM-P), and healthy subjects (H). GCF was collected using paper strips after the sites for GCF collection were clinically evaluated for probing depth (PD), gingival index (GI), and bleeding on probing (BOP). YKL-40 in GCF was identified by Western blotting, and its level was determined by ELISA.

RESULTS

YKL-40 was contained in GCF samples from H, DM, CP, and DM-P sites, and its levels (amount and concentration) in CP and DM-P were significantly higher than those in H and DM. GCF YKL-40 level significantly correlated with PD and GI, and its level in BOP-positive sites was significantly higher than that in BOP-negative ones.

CONCLUSIONS

GCF YKL-40 level was elevated in periodontitis, but not DM. YKL-40 in GCF may be an inflammatory marker for periodontitis.

RelB/p50 complexes regulate cytokine-induced YKL-40 expression

The secreted protein, YKL-40, has been proposed as a biomarker of a variety of human diseases characterized by ongoing inflammation, including chronic neurologic pathologies such as multiple sclerosis and Alzheimer's disease. However, inflammatory mediators and the molecular mechanism responsible for enhanced expression of YKL-40 remained elusive. Using several mouse models of inflammation, we now show that YKL-40 expression correlated with increased expression of both IL-1 and IL-6. Furthermore, IL-1 together with IL-6 or the IL-6 family cytokine, oncostatin M, synergistically upregulated YKL-40 expression in both primary human and mouse astrocytes in vitro. The robust cytokine-driven expression of YKL-40 in astrocytes required both STAT3 and NF-κB binding elements of the YKL-40 promoter. In addition, YKL-40 expression was enhanced by constitutively active STAT3 and inhibited by dominant-negative IκBα. Surprisingly, cytokine-driven expression of YKL-40 in astrocytes was independent of the p65 subunit of NF-κB and instead required subunits RelB and p50. Mechanistically, we show that IL-1-induced RelB/p50 complex formation was further promoted by oncostatin M and that these complexes directly bound to the YKL-40 promoter. Moreover, we found that expression of RelB was strongly upregulated during inflammation in vivo and by IL-1 in astrocytes in vitro. We propose that IL-1 and the IL-6 family of cytokines regulate YKL-40 expression during sterile inflammation via both STAT3 and RelB/p50 complexes. These results suggest that IL-1 may regulate the expression of specific anti-inflammatory genes in nonlymphoid tissues via the canonical activation of the RelB/p50 complexes.

Keeping track of the growing number of biological functions of chitin and its interaction partners in biomedical research

Chitin is a vital polysaccharide component of protective structures in many eukaryotic organisms but seems absent in vertebrates. Chitin or chitin oligomers are therefore prime candidates for non-self-molecules, which are recognized and degraded by the vertebrate immune system. Despite the absence of polymeric chitin in vertebrates, chitinases and chitinase-like proteins (CLPs) are well conserved in vertebrate species. In many studies, these proteins have been found to be involved in immune regulation and in mediating the degradation of chitinous external protective structures of invading pathogens. Several important aspects of chitin immunostimulation have recently been uncovered, advancing our understanding of the complex regulatory mechanisms that chitin mediates. Likewise, the last few years have seen large advances in our understanding of the mechanisms and molecular interactions of chitinases and CLPs in relation to immune response regulation. It is becoming increasingly clear that their function in this context is not exclusive to chitin producing pathogens, but includes bacterial infections and cancer signaling as well. Here we provide an overview of the immune signaling properties of chitin and other closely related biomolecules. We also review the latest literature on chitinases and CLPs of the GH18 family. Finally, we examine the existing literature on zebrafish chitinases, and propose the use of zebrafish as a versatile model to complement the existing murine models. This could especially be of benefit to the exploration of the function of chitinases in infectious diseases using high-throughput approaches and pharmaceutical interventions.

Circulating glioma biomarkers

Validated biomarkers for patients suffering from gliomas are urgently needed for standardizing measurements of the effects of treatment in daily clinical practice and trials. Circulating body fluids offer easily accessible sources for such markers. This review highlights various categories of tumor-associated circulating biomarkers identified in blood and cerebrospinal fluid of glioma patients, including circulating tumor cells, exosomes, nucleic acids, proteins, and oncometabolites. The validation and potential clinical utility of these biomarkers is briefly discussed. Although many candidate circulating protein biomarkers were reported, none of these have reached the required validation to be introduced for clinical practice. Recent developments in tracing circulating tumor cells and their derivatives as exosomes and circulating nuclear acids may become more successful in providing useful biomarkers. It is to be expected that current technical developments will contribute to the finding and validation of circulating biomarkers.

Correlation of chitinase 3-like 1 single nucleotide polymorphisms and haplotypes with uterine cervical cancer in Taiwanese women

Background

This study aimed to investigate the relationships of chitinase 3-like 1 (CHI3L1) single nucleotide polymorphisms (SNPs) and haplotypes with the development of uterine cervical cancer in Taiwanese women. The SNPs frequencies and haplotypes were also correlated with the clinicopathologic variables of cervical cancer, cancer recurrence, and patient survival.

Methodology and Principal Findings

Ninety-nine patients with invasive cancer and 61 with pre-cancerous lesions of the uterine cervix were compared to 310 healthy control subjects. Three SNPs rs6691378 (−1371, G/A), rs10399805 (−247, G/A) and rs4950928 (−131, C/G) in the promoter region, and one SNP rs880633 (+2950, T/C) in exon 5 were analyzed by real time polymerase chain reaction and genotyping. The results showed that the mutant homozygous genotype AA of CHI3L1 SNP rs6691378 and AA of rs10399805, and haplotypes AACC and AACT increased the risk of developing pre-cancerous lesions and invasive cancer. The patients with these risk haplotypes had higher than stage I tumors, larger tumors, and vaginal invasion. In logistic regression model, they also tended to have poor survival event [p = 0.078; odds ratio (OR): 2.99, 95% confidence interval (CI): 0.89–10.08] and a higher probability of recurrence event (p = 0.081; OR: 3.07, 95% CI: 0.87–10.81). There was a significant association between the CHI3L1 risk haplotypes and probability of recurrence (p = 0.002; hazard ratio: 6.21, 95% CI: 1.90–20.41), and a marginal association between the risk haplotypes and overall survival (p = 0.051; hazard ratio: 3.76, 95% CI: 0.99–14.29) in the patients with SCC, using Cox proportional hazard model.

Conclusion

The CHI3L1 SNPs rs6691378 and rs10399805 and CHI3L1 haplotypes all correlated with the development of cervical pre-cancerous lesions and invasive cancer. The cervical cancer patients with the CHI3L1 haplotypes AACC or AACT had poor clinicopathologic characteristics and poor recurrence and survival events. These risk haplotypes were associated with higher recurrence, especially in the patients with SCC.

CHI3L1 plays a role in cancer through enhanced production of pro-inflammatory/pro-tumorigenic and angiogenic factors

Elevated serum levels of a glycoprotein known as chitinase-3-like protein 1 (CHI3L1) have been correlated with poor prognosis and shorter survival of patients with cancer and inflammatory diseases. The biological and physiological functions of CHI3L1 in cancer have not yet been completely elucidated. In this review, we describe the role of CHI3L1 in inducing pro-inflammatory/pro-tumorigenic and angiogenic factors that could promote tumor growth and metastasis.

Increased expression of YKL-40 in mild and moderate/severe persistent allergic rhinitis and its possible contribution to remodeling of nasal mucosa

BACKGROUND

Prominent expression of YKL-40 has been associated with pathological conditions characterized by tissue remodeling. We determined the expression level and distribution pattern of YKL-40 in allergic nasal mucosa and evaluated the effect of YKL-40 on the proliferation and migration of fibroblasts, the production of the mediators related to tissue remodeling, and collagen production. Additionally, the cytokine-driven regulation of YKL-40 expression was evaluated in cultured epithelial cells.

METHODS

The expression of YKL-40 in normal, mild, and moderate/severe allergic nasal mucosa was evaluated using real-time polymerase chain reaction (PCR), Western blot, and immunohistochemistry. Fibroblast migration was observed using a scratch wound method, and proliferation was determined by the MTT methods. Expression of proteoglycans, transforming growth factor (TGF) beta1, MMP2, MMP9, TIMP1, TIMP2, and collagen concentration were analyzed in fibroblasts treated with YKL-40. The expression levels of YKL-40 in cultured epithelial cells were examined after stimulation with mediators including Th2 cytokines, interferon (IFN)gamma, and TNF-alpha with real-time PCR and ELISA.

RESULTS

The expression of YKL-40 was up-regulated in allergic rhinitis and distributed in superficial epithelium, submucosal glands, and vascular endothelium, in addition to infiltrating cells. TGF-beta1, TIMP1, MMP9, and biglycan were up-regulated in fibroblasts on stimulation with YKL-40, accompanying increased proliferation and migration, and collagen production. IL-13, IFN-gamma, and TNF-alpha induced the increased production of YKL-40 in cultured epithelial cells.

CONCLUSION

YKL-40 is up-regulated in mild and moderate/severe persistent allergic rhinitis, and its expression can be regulated differentially by different cytokines, possibly contributing to the remodeling of nasal mucosa in allergic rhinitis.

Antibody directed against human YKL-40 increases tumor volume in a human melanoma xenograft model in scid mice

Induced overexpression of the secretory protein YKL-40 promotes tumor growth in xenograft experiments. We investigated if targeting YKL-40 with a monoclonal antibody could inhibit tumor growth. YKL-40 expressing human melanoma cells (LOX) were injected subcutenously in Balb/c scid mice. Animals were treated with intraperitoneal injections of anti-YKL-40, isoptype control or PBS. Non-YKL-40 expressing human pancreatic carcinoma cell line PaCa 5061 served as additional control. MR imaging was used for evaluation of tumor growth. Two days after the first injections of anti-YKL-40, tumor volume had increased significantly compared with controls, whereas no effects were observed for control tumors from PaCa 5061 cells lacking YKL-40 expression. After 18 days, mean tumor size of the mice receiving repeated anti-YKL-40 injections was 1.82 g, >4 times higher than mean tumor size of the controls (0.42 g). The effect of anti-YKL-40 on the increase of tumor volume started within hours after injection and was dose dependent. Intratumoral hemorrhage was observed in the treated animals. The strong effect on tumor size indicates important roles for YKL-40 in melanoma growth and argues for a careful evaluation of antibody therapy directed against YKL-40.

Serum YKL-40 levels and chitotriosidase activity in patients with beta-thalassemia major

BACKGROUND

YKL-40 association with human disease has been the object of many years of investigation. β-thalassemia patients are affected by hepatic siderosis, which determines a fibrotic process and tissue remodelling. Chitotriosidase has been found to be increased in thalassemic patients returning to normal in patients submitted to bone marrow transplantation. YKL-40 is associated with macrophage activation in liver and in other tissues. The aim of the study was to analyse the level of serum YKL-40 and plasma chitotriosidase activity of patients with beta-thalassemia to assess whether their expression correlates with liver disease and degree of liver siderosis.

METHODS

Expression of YKL-40 and chitotriosidase as a marker of inflammation in 69 thalassemic patients were evaluated. We sought to investigate whether these two chitinases could be considered as a significant biomarker to evaluate therapy effectiveness.

RESULTS

Surprisingly we found normal value of YKL-40. We, also, analysed chitotriosidase activity in the same patients that was slightly increased as a consequence of macrophage activation.

CONCLUSIONS

These data would suggest a good treatment for these patients.

Cells from the skin of patients with systemic sclerosis secrete chitinase 3-like protein 1

Background

The chitinase-like protein, Chi3L1, is associated with increased fibrotic activity as well as inflammatory processes. The capacity of skin cells from systemic sclerosis (SSc) patients to produce Chi3L1, and the stimulation of its synthesis by cytokines or growth factors known to be associated with SSc, was investigated.

Methods

Cells were isolated from forearm and/or abdomen skin biopsies taken from SSc patients and normal individuals and stimulated with cytokines and growth factors to assess Chi3L1 expression. Chi3L1-expressing cells were characterized by immunohistochemical staining.

Results

Chi3L1 was not secreted by skin cells from normal individuals nor was its synthesis induced by any of the cytokines or growth factors investigated. In contrast, Chi3L1 secretion was induced by OSM or IL-1 in cells from all forearm biopsies of SSc patients, and endogenous secretion in the absence of cytokines was detected in several specimens. Patients with Chi3L1-producing cells at both the arm and abdomen had a disease duration of less than 3 years. Endogenous Chi3L1 production was not a property of the major fibroblast population nor of myofibroblasts, but rather was related to the presence of stem-like cells not present in normal skin. Other cells, however, contributed to the upregulation of Chi3L1 by OSM.

Conclusions

The emergence of cells primed to respond to OSM with increased Chi3L1 production appears to be associated with pathological processes active in SSc.

General significance

The presence of progenitor cells expressing the chilectin Chi3L1 in SSc skin appears to play a role in the initiation of the disease process.

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Cells isolated from the skin of scleroderma patients secrete Chi3L1.

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Chi3L1 production is stimulated by oncostatin M or interleukin 1.

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Patients with Chi3L1 producing cells have disease duration of < 3 years.

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Chi3L1 production is a property of stem-like cells not present in normal skin.

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Other cells contribute to Chi3L1 upregulation by oncostatin M.

A novel biomarker-based analysis reliably predicts nodal metastases in anal carcinoma: preliminary evidence of therapeutic impact

AIM

Routine prophylactic inguinal irradiation in anal cancer may cause significant toxicity associated with overtreatment bias. The aim of this study was to determine the risk of regional node metastases in anal carcinoma by identifying predictive molecular biomarkers.

METHOD

Clinicohistopathological data from 50 pretreatment anal carcinoma biopsies were collected. Immunohistochemical analyses with antibodies against Ki67, p53, epidermal growth factor receptor (EGFR) and YKL-40 were performed. Statistical correlations between biomarkers and clinicopathological features and outcomes were studied. Sentinel lymph node biopsy was performed in a subset of 36 patients.

RESULTS

All patients had undergone synchronous radiochemotherapy; tumour recurrence had developed in 26%, and 16% had died. YKL-40 tumour expression correlated with lymph node metastasis, whereas no inguinal node metastases were found in any of the (14%) patients presenting with a YKL-40/EGFR-negative tumour. YKL-40 expression and node metastasis were both significantly associated with shorter overall and disease-free survival. Tumour grade significantly correlated with disease-free survival only. HIV, tumour histological type, Ki67, p53 and EGFR were not associated with outcome.

CONCLUSION

YKL-40 expression in anal carcinoma is correlated with a poor outcome and can predict lymph node metastases. The combined absence of YKL-40 and EGFR expression in a first biopsy of anal carcinoma reliably selects a subset of patients without inguinal metastases. Such patients could be spared sentinel lymph node biopsy and/or inguinal radiotherapy.