Role of YKL-40 in the angiogenesis, radioresistance, and progression of glioblastoma

Changes in serum levels of Chitinase protein-40 in children with Kawasaki disease and its clinical significance

OBJECTIVES

Kawasaki disease (KD) is an acute immune-mediated vasculitis primarily affecting coronary arteries, with limited specific diagnostic biomarkers available. Chitinase protein-40 (YKL-40), a glycoprotein secreted by neutrophils and macrophages, has been associated with vascular inflammation in cardiovascular diseases. This study aimed to investigate the role of YKL-40 in KD by analyzing its serum levels, correlations with inflammatory markers, and potential as a diagnostic and prognostic biomarker.

METHODS

Serum YKL-40 and interleukin-6 (IL-6) levels were measured using enzyme-linked immunosorbent assay (ELISA) in 46 children with KD (16 with coronary artery lesions [CAL], 30 without CAL) and 30 healthy controls. Correlations between YKL-40, IL-6, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), white blood cell (WBC) count, and platelet (PLT) levels were analyzed.

RESULTS

YKL-40, IL-6, CRP, ESR, WBC, and PLT levels were significantly elevated in KD patients compared to controls. YKL-40 levels correlated positively with IL-6, CRP, and ESR. A serum YKL-40 threshold of ≥ 71.930 ng/mL predicted CAL with sensitivity and specificity of 0.875 and 0.800, respectively. Combining YKL-40 with IL-6 improved sensitivity and specificity to 0.938 and 0.833.

CONCLUSIONS

YKL-40 is significantly elevated in KD and correlates with inflammatory markers, suggesting its involvement in disease pathogenesis. It is a promising inflammatory biomarker and independent risk factor for predicting CAL in KD, offering potential for improved diagnosis and prognosis.

CLINICAL TRIAL NUMBER

Not applicable.

Novel CHI3L1-Associated Angiogenic Phenotypes Define Glioma Microenvironments: Insights From Multi-Omics Integration

The CHI3L1 signaling pathway significantly influences glioma angiogenesis, but its role in the tumor microenvironment (TME) remains elusive. We propose a novel CHI3L1-associated vascular phenotype classification for glioma through integrative analyses of multiple datasets with bulk and single-cell transcriptome, genomics, digital pathology, and clinical data. We investigated the biological characteristics, genomic alterations, therapeutic vulnerabilities, and immune profiles within these phenotypes through a comprehensive multi-omics approach. We constructed the vascular-related risk (VR) score based on CHI3L1-associated vascular signatures (CAVS) identified by machine learning algorithms. Utilizing unsupervised consensus clustering, gliomas were stratified into three distinct vascular phenotypes: Cluster A, marked by high vascularization and stromal activation with a relatively low levels of tumor-infiltrating lymphocytes (TILs); Cluster B, characterized by moderate vascularization and stromal activity, coupled with a high density of TILs; and Cluster C, defined by low vascularization and sparse immune cell infiltration. We observed that the CAVS effectively indicated glioma-associated angiogenesis and immune suppression by single-cell RNA-seq analysis. Moreover, the high-VR-score group exhibited enhanced angiogenic activity, reduced immune response, resistance to immunotherapy, and poorer clinical outcomes. The VR score independently predicted glioma prognosis and, combined with a nomogram, provided a robust clinical decision-making tool. Potential drug prediction based on transcription factors for high-risk patients was also performed. Our study reveals that CHI3L1-associated vascular phenotypes shape distinct immune landscapes in gliomas, offering insights for optimizing therapeutic strategies to improve patient outcomes.

YKL-40 inhibits melanoma progression and metastasis by inducing immune cell infiltration in a mouse model

YKL-40 is a glycoprotein that has been extensively studied due to its elevated expression in numerous solid tumors, and its expression is altered in melanoma, where its levels in tumor tissues are notably lower compared with those in normal skin tissues. Patients with melanoma exhibiting high YKL-40 expression have improved survival rates, suggesting a potential tumor-suppressive function of YKL-40 in melanoma. The present investigation into the ectopic expression of YKL-40 in human (A375) and murine (B16F10) melanoma cell lines demonstrated a consequential decrease in cell proliferation, migration and invasion. Furthermore, YKL-40 overexpression was associated with suppressed tumor growth in a subcutaneous melanoma mouse model and diminished tumor cell metastasis in a pulmonary metastasis model. RNA-sequencing analysis revealed that YKL-40 overexpression led to the upregulation of immune cell infiltration-related signaling pathways, including cytokine receptor interactions, natural killer cell-mediated cytotoxicity, and T and B lymphocyte receptor signaling. These findings highlight the potential of YKL-40 as a regulator of tumor-immune interactions in melanoma, highlighting its prospective utility in immunotherapy-based treatment strategies for melanoma.

Heparin-binding of the human chitinase-like protein YKL-40 is allosterically modified by chitin oligosaccharides

The chitinase-like protein YKL-40 (CHI3L1) has been implicated in the pathophysiology of inflammation and cancer. Recent studies highlight the growing interest in targeting and blocking the activity of YKL-40 to treat cancer. Some of those targeting-strategies have been developed to directly block the heparin-affinity of YKL-40 with promising results. This study explores how short chain chitooligosaccharides (ChOS) affect the heparin-binding affinity of YKL-40. Our findings reveal that ChOS act as allosteric effectors, decreasing the heparin-binding affinity of YKL-40 in a size- and dose-dependent manner. Our results provide insights into the heparin affinity of YKL-40 and how ChOS can be used to target the heparin activity of YKL-40 in diseases. Since ChOS has many beneficial properties, such as being non-toxic and biodegradable, these results provide intriguing opportunities for applying them as allosteric effectors of the heparin-binding affinity of YKL-40.

Inhibition of CHI3L1 decreases N-cadherin and VCAM-1 levels in glioblastoma

BACKGROUND

The protein CHI3L1 contributes to cancer development by several mechanisms, including stimulation of angiogenesis and invasion as well as immunomodulatory effects. These properties make it a potential target for the development of targeted therapies in precision medicine. In this context, the particular potential of CHI3L1 inhibition could be considered in glioblastoma multiforme (GBM), whose tumors exhibit high levels of angiogenesis and increased CHI3L1 expression. This study aims to investigate whether inhibition of CHI3L1 in spheroids used as a GBM model affects the mechanisms of invasiveness; METHODS: We analyzed the interactions between CHI3L1 and the inhibitor G721-0282 in molecular docking and molecular dynamics (in silico) and infrared spectroscopy. Uptake of G721-0282 in GBM spheroids was measured using a label-free physical cytometer. Changes in E-, N- and VE-cadherins, VCAM-1, and EGFR were analyzed by immunohistochemical reactions, Western blot, and ddPCR methods in U-87 MG cells and GBM spheroids consisting of U-87 MG glioblastoma cells, HMEC-1 endothelial cells and macrophages; RESULTS: A direct interaction between CHI3L1 and G721-0282 was confirmed. G721-0282 decreased N-cadherins and VCAM-1 in GBM spheroids, but the changes in the 2D model of U-87 MG glioblastoma cells were different; CONCLUSION: Inhibition of CHI3L1 has the potential to reduce the invasiveness of GBM tumors. The 3D model of GBM spheroids is of great significance for investigating changes in membrane proteins and the tumor microenvironment.

Chitinase-3-like-1: a multifaceted player in neuroinflammation and degenerative pathologies with therapeutic implications

Chitinase-3-like-1 (CHI3L1) is an evolutionarily conserved protein involved in key biological processes, including tissue remodeling, angiogenesis, and neuroinflammation. It has emerged as a significant player in various neurodegenerative diseases and brain disorders. Elevated CHI3L1 levels have been observed in neurological conditions such as traumatic brain injury (TBI), Alzheimer's disease (AD), Parkinson's disease (PD), Amyotrophic lateral sclerosis (ALS), Creutzfeldt-Jakob disease (CJD), multiple sclerosis (MS), Neuromyelitis optica (NMO), HIV-associated dementia (HAD), Cerebral ischemic stroke (CIS), and brain tumors. This review explores the role of CHI3L1 in the pathogenesis of these disorders, with a focus on its contributions to neuroinflammation, immune cell infiltration, and neuronal degeneration. As a key regulator of neuroinflammation, CHI3L1 modulates microglia and astrocyte activity, driving the release of proinflammatory cytokines that exacerbate disease progression. In addition to its role in disease pathology, CHI3L1 has emerged as a promising biomarker for the diagnosis and monitoring of brain disorders. Elevated cerebrospinal fluid (CSF) levels of CHI3L1 have been linked to disease severity and cognitive decline, particularly in AD and MS, highlighting its potential for clinical diagnostics. Furthermore, therapeutic strategies targeting CHI3L1, such as small-molecule inhibitors and neutralizing antibodies, have shown promise in preclinical studies, demonstrating reduced neuroinflammation, amyloid plaque accumulation, and improved neuronal survival. Despite its therapeutic potential, challenges remain in developing selective and safe CHI3L1-targeted therapies, particularly in ensuring effective delivery across the blood-brain barrier and mitigating off-target effects. This review addresses the complexities of targeting CHI3L1, highlights its potential in precision medicine, and outlines future research directions aimed at unlocking its full therapeutic potential in treating neurodegenerative diseases and brain pathologies.

Prognostic significance of YKL-40 expression in canine cutaneous mast cell tumors

BACKGROUND

YKL-40, a secretory glycoprotein, is involved in tumor cell proliferation, metastasis, and angiogenesis in human cancers. Its overexpression has been correlated with unfavorable prognosis in many human cancers. In veterinary medicine, elevated YKL-40 levels in the serum of canine cutaneous mast cell tumors (cMCTs) were observed in our previous study. However, the expression pattern of YKL-40 in canine cMCT tissues, along with its association with clinical and pathological features, is still unknown. This study aims to retrospectively investigate the expression level of YKL-40 in the tissues of canine cMCTs and its correlation with clinical features, pathological characteristics, and clinical outcomes. Forty formalin-fixed paraffin-embedded cMCT tissues collected from forty dogs were diagnosed as low-grade (n = 20) or high-grade s(n = 20) MCT according to the Kiupel grading system. The expression level of YKL-40 in cMCT tissues was investigated using immunohistochemical staining and immunoreactivity score (IRS).

RESULTS

YKL-40 was expressed in all cMCTs at different levels, with significantly stronger expression in low-grade cMCTs compared to high-grade cMCTs. The expression level was also associated with tumor diameter, histological grade, mitotic counts, vessel density, and survival of cMCTs. The overall survival of cMCT dogs showed significant differences (p < 0.01) among mild (n = 15, MST 219 days), moderate (n = 19, MST not reached), and high (n = 6, MST not reached) YKL-40 expression groups. Among low-grade cMCTs, overall survival was significantly different between mild YKL-40 expression (MST 319 days) and moderate to high YKL-40 (MST not reached) expression (p < 0.01). In high-grade cMCTs, overall survival was not correlated with YKL-40 expression (p = 0.6589).

CONCLUSIONS

This study found that the YKL-40 expression level was significantly stronger in low-grade than in high-grade canine cutaneous mast cell tumors and was associated with various clinical and pathological features. Stronger YKL-40 expression level correlated with longer survival time, especially in low-grade cMCTs. Therefore, YKL-40 could serve as a prognostic marker for cMCTs.

New insights into the role of the CHI3L2 protein in invasive ductal breast carcinoma

Chitinase-like proteins have multiple biological functions that promote tumor growth, angiogenesis and metastasis. Expression of CHI3L2, which is similar in structure to CHI3L1, is detected in glioma cells and tumor-associated macrophages (TAMs) in glioma and breast cancer. However, its exact role remains unclear. We analyzed the expression of CHI3L2 in 74 invasive ductal breast carcinoma (IDC) tumors, breast cancer and macrophages cell cultures using immunohistochemistry, immunofluorescence, Western blot and PCR methods. Clinicopathologic data were included in the analysis. The results obtained show that CHI3L2 expression decreases with increasing degree of tumor grade and negative status of estrogen (ER) and progesterone receptors (PR). Furthermore, CHI3L2 is significantly and positively correlated with phosphorylation of STAT-3 and ERK1/2 signaling pathways, but negatively correlated with macrophage infiltration. CHI3L2 is expressed both in the cytoplasm of cancer cells and in macrophages and may regulate STAT-3 and ERK1/2 phosphorylation in breast cancer cell lines. Analysis of the clinicopathologic data revealed that CHI3L2 levels had no effect on patient survival. CHI3L2 expression may be specific for cancer cells in IDC and involved in cross-talk with the tumor microenvironment. Our study has shown that IDC cancer cells express the CHI3L2 protein, possibly indicating a novel function of this protein.

Serum CHI3L1 Levels Predict Overall Survival of Hepatocellular Carcinoma Patients after Hepatectomy

Objective: The Chitinase 3-like protein 1 (CHI3L1) is currently used as a biomarker for the diagnosis of liver fibrosis. However, its prognostic value for hepatocellular carcinoma (HCC) patients remains controversial. In this study, we aimed to investigate the prognostic value of the CHI3L1 in HCC patients after hepatectomy. Methods: In total, 753 HCC patients who underwent curative hepatectomy between January 2017 to August 2021 were retrospectively recruited. The probability of overall survival (OS) was evaluated by the Kaplan-Meier method and compared between groups using the log-rank test. Cox proportional hazard regression analysis was used to determine the independent prognostic factors. A prognostic nomogram was constructed for further examine the clinical utility of CHI3L1 in HCC. Results: Kaplan-Meier analysis revealed that elevated serum CHI3L1 levels were associated with worse overall survival of HCC patients. Multivariate Cox regression analysis showed that the high-CHI3L1 group (≥198.94 ng/ml) was associated with a shorter survival time compared with that in the low-CHI3L1 group (< 198.94 ng/ml) after adjustment for potential confounding factors (HR =1.43, 95% CI = 1.05-1.94, P = 0.024). Additionally, the nomogram had sufficient calibration and discriminatory power in the training cohort, with C-indexes of 0.723 (95% CI: 0.673-0.772). The validation cohort showed similar results. Finally, we demonstrated that the AUC of the nomogram was 0.752 (95% CI: 0.683-0.821), which had better predictive ability than AFP (AUC: 0.644, 95% CI: 0.577-0.711). Conclusion: Our results confirmed that the CHI3L1 could serve as an independent predictor for OS in HCC patients after hepatectomy. The nomogram showed a good performance in prognosis prediction of HCC.

Chitinase‑3 like‑protein‑1: A potential predictor of cardiovascular disease (Review)

Chitinase‑3 like‑protein‑1 (CHI3L1), a glycoprotein belonging to the glycoside hydrolase family 18, binds to chitin; however, this protein lacks chitinase activity. Although CHI3L1 is not an enzyme capable of degrading chitin, it plays significant roles in abnormal glucose and lipid metabolism, indicating its involvement in metabolic disorders. In addition, CHI3L1 is considered a key player in inflammatory diseases, with clinical data suggesting its potential as a predictor of cardiovascular disease. CHI3L1 regulates the inflammatory response of various cell types, including macrophages, vascular smooth muscle cells and fibroblasts. In addition, CHI3L1 participates in vascular remodeling and fibrosis, contributing to the pathogenesis of cardiovascular disease. At present, research is focused on elucidating the role of CHI3L1 in cardiovascular disease. The present systematic review was conducted to comprehensively evaluate the effects of CHI3L1 on cardiovascular cells, and determine the potential implications in the occurrence and progression of cardiovascular disease. The present study may further the understanding of the involvement of CHI3L1 in cardiovascular pathology, demonstrating its potential as a therapeutic target or biomarker in the management of cardiovascular disease.

Inhibition of CHI3L1 decreases N-cadherin and VCAM-1 levels in glioblastoma

Background

(1)The protein CHI3L1 supports cancer development in several ways, including stimulation of angiogenesis and invasion as well as immunomodulatory effects. These properties make it a potential target for the development of targeted therapies in precision medicine. In this context, the particular potential of CHI3L1 inhibition could be considered in glioblastoma multiforme (GBM), whose tumors exhibit high levels of angiogenesis and increased CHI3L1 expression. This study aims to investigate whether inhibition of CHI3L1 in spheroids used as a GBM model affects the mechanisms of invasiveness.

Methods

(2)We analyzed the interactions between CHI3L1 and the inhibitor G721-0282 in molecular docking (in silico) and infrared spectroscopy. Uptake of G721-0282 in GBM spheroids was measured using a label-free physical cytometer. Changes in E-, N- and VE-cadherins, VCAM-1 and EGFR were analyzed by immunohistochemical reactions, Western blot and ddPCR methods in U-87 MG cells and GBM spheroids consisting of U-87 MG glioblastoma cells, HMEC-1 endothelial cells and macrophages.

Results

(3)A direct interaction between CHI3L1 and G721-0282 was observed. G721-0282 decreased N-cadherins and VCAM-1 in GBM spheroids, but the changes in the 2D model of U-87 MG glioblastoma cells were different.

Conclusion

(4)Inhibition of CHI3L1 has the potential to reduce the invasiveness of GBM tumors. The proposed 3D model of GBM spheroids is of great significance for investigating changes in membrane proteins and the tumor microenvironment.

Natural glyceollin soybean extracts elicited with Aspergillus sojae reduce estrogen-dependent breast cancer growth in orally fed mice

Previous studies have demonstrated antiestrogenic and antiproliferative effects of these molecules in breast cancer cells. Notably, we have reported that pure synthetic glyceollins I and II act through various pathways, including ERα, FOXM1, AhR, and HIF pathways to inhibit cell proliferation and migration. In this study, the potential antitumor activity of glyceollins enriched in crude soybean extracts, obtained by solid fermentation with Aspergillus sojae, was investigated in vivo on MCF-7 breast cancer cells implanted in the chorioallantoic membrane of the chick egg and on ovariectomized nude mice. The first trial showed a substantial reduction in the migration of MCF-7 cells treated with the natural extracts. However, the natural extracts significantly reduced the estrogen-dependent growth of transplanted tumors in orally fed nude mice. Our results showed that natural soybean extracts slightly but significantly reduced estrogen-dependent growth of the transplanted tumors in orally fed nude mice. These results were confirmed by immunohistochemistry of Ki-67 and histone H3S10 phosphorylation (H3S10P), revealing lower expression of these proliferation markers in the transplanted tumors from mice fed with the fermented extracts. Additionally, compared to the control animals, we observed a lower expression of angiogenesis markers such as CD31 and CD34. Surprisingly, transcriptomic analysis of RNA from transplanted MCF-7 cells revealed no differential gene expression. These results may suggest that orally consumed natural glyceollins exert biological effects throughout the body, acting indirectly to reduce tumor angiogenesis and consequently tumor volume. Overall, our results indicate that glyceollins, elicited components of the soy origin, hold potential therapeutic applications for the prevention and treatment of breast cancer.

Uncovering novel mechanisms of chitinase-3-like protein 1 in driving inflammation-associated cancers

Chitinase-3-like protein 1 (CHI3L1) is a secreted glycoprotein that is induced and regulated by multiple factors during inflammation in enteritis, pneumonia, asthma, arthritis, and other diseases. It is associated with the deterioration of the inflammatory environment in tissues with chronic inflammation caused by microbial infection or autoimmune diseases. The expression of CHI3L1 expression is upregulated in several malignant tumors, underscoring the crucial role of chronic inflammation in the initiation and progression of cancer. While the precise mechanism connecting inflammation and cancer is unclear, the involvement of CHI3L1 is involved in chronic inflammation, suggesting its role as a contributing factor to in the link between inflammation and cancer. CHI3L1 can aggravate DNA oxidative damage, induce the cancerous phenotype, promote the development of a tumor inflammatory environment and angiogenesis, inhibit immune cells, and promote cancer cell growth, invasion, and migration. Furthermore, it participates in the initiation of cancer progression and metastasis by binding with transmembrane receptors to mediate intracellular signal transduction. Based on the current research on CHI3L1, we explore introduce the receptors that interact with CHI3L1 along with the signaling pathways that may be triggered during chronic inflammation to enhance tumorigenesis and progression. In the last section of the article, we provide a brief overview of anti-inflammatory therapies that target CHI3L1.

Prognostic and predictive role of YKL-40 in anal squamous cell carcinoma: a serological and tissue-based analysis in a multicentric cohort

Introduction

Anal squamous cell carcinoma (ASC) is a rare gastrointestinal malignancy showing an increased incidence over the past decades. YKL-40 is an immune modulator and pro-angiogenetic factor that showed a promising prognostic and predictive potential in several malignancies, but limited data are available for ASC. This study aims to provide an extensive evaluation of the prognostic and predictive role of YKL-40 in a multicenter cohort of ASC patients.

Methods

We retrospectively retrieved 72 consecutive cases of ASC diagnosed between February 2011 and March 2021. Both serum and tissue protein expression of YKL-40 were assessed, the latter in ASC tumor cells and peritumor immune cells.

Results

Increased YKL-40 serum levels at the time of diagnosis were associated with older age (p = 0.035), presence of cardiovascular/metabolic comorbidities (p = 0.007), and death for any cause (p = 0.011). In addition, high serum levels of YKL-40 were associated with a poor prognosis (HR: 2.82, 95% CI: 1.01-7.84; p = 0.047). Protein expression of YKL-40 in ASC tumor cells was significantly associated with low tumor grade (p = 0.031), while the increased expression in peritumor immune cells was associated with a worse response of patients to chemoradiotherapy (p = 0.007). However, YKL-40 protein expression in ASC tumor cells or peritumor immune cells did not significantly impact patient overall survival.

Discussion

In conclusion, YKL-40 resulted a relevant prognostic (serum level) and predictive (tissue protein expression in peritumor immune cells) biomarker and can considerably improve ASC patient clinical management.

Fully human chitinase-3 like-1 monoclonal antibody inhibits tumor growth, fibrosis, angiogenesis, and immune cell remodeling in lung, pancreatic, and colorectal cancers

Considering the limited efficacy of current therapies in lung, colorectal, and pancreatic cancers, innovative combination treatments with diverse mechanisms of action are needed to improve patients' outcomes. Chitinase-3 like-1 protein (CHI3L1) emerges as a versatile factor with significant implications in various diseases, particularly cancers, fostering an immunosuppressive tumor microenvironment for cancer progression. Therefore, pre-clinical validation is imperative to fully realize its potential in cancer treatment. We developed phage display-derived fully human monoclonal CHI3L1 neutralizing antibodies (nAbs) and verified the nAbs-antigen binding affinity and specificity in lung, pancreatic and colorectal cancer cell lines. Tumor growth signals, proliferation and migration ability were all reduced by CHI3L1 nAbs in vitro. Orthotopic or subcutaneous tumor mice model and humanized mouse model were established for characterizing the anti-tumor properties of two CHI3L1 nAb leads. Importantly, CHI3L1 nAbs not only inhibited tumor growth but also mitigated fibrosis, angiogenesis, and restored immunostimulatory functions of immune cells in pancreatic, lung, and colorectal tumor mice models. Mechanistically, CHI3L1 nAbs directly suppressed the activation of pancreatic stellate cells and the transformation of macrophages into myofibroblasts, thereby attenuating fibrosis. These findings strongly support the therapeutic potential of CHI3L1 nAbs in overcoming clinical challenges, including the failure of gemcitabine in pancreatic cancer.

Inhibition of Chitinase-3-like Protein 1 Reduced Epithelial-Mesenchymal Transition and Vascular Epithelial Cadherin Expression in Oesophageal Squamous Cell Carcinoma

Background

Oesophageal cancer (EC) is one of the common malignant tumors, and the prognosis of patients is poor. Further exploration of EC pathogenesis remains warranted.

Objective

The relationship between vascular epithelial cadherin (VE-cadherin) and chitinase-3-like protein 1 (CHI3L1) in EC is currently unknown. To further explore the relationship, immunohistochemical staining was performed to detect the expression level of CHI3L1 and VE-cadherin in oesophageal squamous cell carcinoma ( ESCC).

Materials and Methods

Small interfering RNAs (siRNAs) inhibited CHI3L1 expression in KYSE-150 and TE1 cells. Western blot and quantitative fluorescence polymerase chain reaction were used to detect the levels of CHI3L1, VE-cadherin and epithelial-mesenchymal transition (EMT)-related proteins in vitro and in vivo, and KYSE-150 cells were used to establish an in-vivo model and observe tumour growth.

Results

High levels of CHI3L1 and VE-cadherin expression were closely associated with the progression of ESCC; the pathologic tumour-node-metastasis stage was also closely related with the progression of ESCC (p < 0.05). High levels of CHI3L1 and VE-cadherin expression led to poor prognosis in patients with EC. In KYSE-150 and TE1 EC cell lines, the invasion, migration and proliferation of cells decreased, and the apoptotic rate increased after CHI3L1 expression was decreased using siRNA. The CHI3L1, VE-cadherin, Snail, Twist1 protein and mRNA expression levels decreased, whereas the E-cadherin levels increased.

Conclusions

Chitinase-3-like protein 1 could promote the EMT of ESCC, and the inhibition of CHI3L1 decreases the expression of VE-cadherin, which inhibits tumour angiogenesis and tumour progression in ESCC.

Chitinase 3 like-1 activates the Akt pathway, inducing NF-κB-dependent release of pro-inflammatory cytokines and promoting the proliferative ability in nasopharyngeal carcinoma cells

BACKGROUND

Chitinase 3 like-1 (CHI3L1) has been reported to function as an oncogene in many types of cancer. However, the biological function of CHI3L1 in nasopharyngeal carcinoma (NPC) remains unknown.

METHODS

Differentially expressed genes (DEGs) in NPC tissues in GSE64634 and GSE12452 were downloaded from Gene Expression Omnibus (GEO). CHI3L1, interleukin 6 (IL-6), and tumor necrosis factor α (TNF-α) mRNA expression was examined by qRT-PCR. Cell proliferation was evaluated by CCK-8 and EdU incorporation assays. Western blot analysis was used to measure the changes of CHI3L1, nuclear factor-κappaB (NF-κB), and protein kinase B (Akt) pathways. Gene ontology (GO) enrichment and Kyoto Encyclopedia of Gene and Genome (KEGG) pathway analyses were performed using DAVID database.

RESULTS

We identified 3 overlapping DEGs using Draw Venn diagram, among which CHI3L1 was chosen for the following analyses. CHI3L1 was upregulated in NPC tissues and cells. CHI3L1 silencing suppressed inflammatory response by inactivating the NF-κB pathway and inhibited cell proliferation in NPC cells. On the contrary, CHI3L1 overexpression induced inflammatory response by activating the NF-κB pathway and promoted cell proliferation in NPC cells. According to GO and KEGG analyses, CHI3L1 positive regulates Akt signaling and is enriched in the PI3K-Akt pathway. CHI3L1 knockdown inhibited the Akt pathway, and CHI3L1 overexpression activated the Akt pathway in NPC cells. Akt overexpression abolished the effects of CHI3L1 knockdown on inflammatory response, NF-κB pathway, and proliferation in NPC cells. On the contrary, Akt knockdown abolished the effects of CHI3L1 overexpression on inflammatory response, NF-κB pathway, and proliferation in NPC cells.

CONCLUSION

CHI3L1 knockdown inhibited NF-κB-dependent inflammatory response and promoting proliferation in NPC cells by inactivating the Akt pathway.

A humanized Anti-YKL-40 antibody inhibits tumor development

Drugs specifically targeting YKL-40, an over-expressed gene (CHI3L1) in various diseases remain developed. The current study is to create a humanized anti-YKL-40 neutralizing antibody and characterize its potentially therapeutic signature. We utilized in silico CDR-grafting bioinformatics to replace the complementarity determining regions (CDRs) of human IgG1 with mouse CDRs of our previously established anti-YKL-40 antibody (mAY). In fifteen candidates (VL1-3/VH1-5) of heavy and light chain variable region combination, one antibody L3H4 named Rosazumab demonstrated strong binding affinity with YKL-40 (KD = 4.645 × 10-8 M) and high homology with human IgG (80 %). In addition, we established different overlapping amino acid peptides of YKL-40 and found that Rosazumab specifically bound to residues K337, K342, and R344, the KR-rich functional domain of YKL-40. Rosazumab inhibited migration and tube formation of YKL-40-expressing tumor cells and induced tumor cell apoptosis. Mechanistically, Rosazumab induced interaction of N-cadherin with β-catenin and activation of downstream MST1/RASSF1/Histone H2B axis, leading to chromosomal DNA breakage and cell apoptosis. Treatment of xenografted tumor mice with Rosazumab twice a week for 4 weeks inhibited tumor growth and angiogenesis, but induced tumor apoptosis. Rosazumab injected in mice distributed to blood, tumor, and other multiple organs, but did not impact in function or structure of liver and kidney, indicating non-detectable toxicity in vivo. Collectively, the study is the first one to demonstrate that a humanized YKL-40 neutralizing antibody offers a valuable means to block tumor development.

Secreted Glycoproteins That Regulate Synaptic Function: the Dispatchers in the Central Nervous System

Glycoproteins are proteins that contain oligosaccharide chains. As widely distributed functional proteins in the body, glycoproteins are essential for cellular development, cellular function maintenance, and intercellular communication. Glycoproteins not only play a role in the cell and the membrane, but they are also secreted in the intercell. These secreted glycoproteins are critical to the central nervous system for neurodevelopment and synaptic transmission. More specifically, secreted glycoproteins play indispensable roles in neurite growth mediation, axon guiding, synaptogenesis, neuronal differentiation, the release of synaptic vesicles, subunit composition of neurotransmitter receptors, and neurotransmitter receptor trafficking among other things. Abnormal expressions of secreted glycoproteins in the central nervous system are associated with abnormal neuron development, impaired synaptic organization/transmission, and neuropsychiatric disorders. This article reviews the secreted glycoproteins that regulate neuronal development and synaptic function in the central nervous system, and the molecular mechanism of these regulations, providing reference for research about synaptic function regulation and related central nervous system diseases.

CD138 as a Specific CSF Biomarker of Multiple Sclerosis

BACKGROUND AND OBJECTIVES

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

METHODS

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

RESULTS

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

DISCUSSION

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

CLASSIFICATION OF EVIDENCE

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

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.

Significance of chitinase-3-like protein 1 in the pathogenesis of inflammatory diseases and cancer

Chitinase-3-like protein 1 (CHI3L1) is a secreted glycoprotein that mediates inflammation, macrophage polarization, apoptosis, and carcinogenesis. The expression of CHI3L1 is strongly upregulated by various inflammatory and immunological diseases, including several cancers, Alzheimer's disease, and atherosclerosis. Several studies have shown that CHI3L1 can be considered as a marker of disease diagnosis, prognosis, disease activity, and severity. In addition, the proinflammatory action of CHI3L1 may be mediated via responses to various proinflammatory cytokines, including tumor necrosis factor-α, interleukin-1β, interleukin-6, and interferon-γ. Therefore, CHI3L1 may contribute to a vast array of inflammatory diseases. However, its pathophysiological and pharmacological roles in the development of inflammatory diseases remain unclear. In this article, we review recent findings regarding the roles of CHI3L1 in the development of inflammatory diseases and suggest therapeutic approaches that target CHI3L1.

Potential Roles and Future Perspectives of Chitinase 3-like 1 in Macrophage Polarization and the Development of Diseases

Chitinase-3-like protein 1 (CHI3L1), a chitinase-like protein family member, is a secreted glycoprotein that mediates macrophage polarization, inflammation, apoptosis, angiogenesis, and carcinogenesis. Abnormal CHI3L1 expression has been associated with multiple metabolic and neurological disorders, including diabetes, atherosclerosis, and Alzheimer's disease. Aberrant CHI3L1 expression is also reportedly associated with tumor migration and metastasis, as well as contributions to immune escape, playing important roles in tumor progression. However, the physiological and pathophysiological roles of CHI3L1 in the development of metabolic and neurodegenerative diseases and cancer remain unclear. Understanding the polarization relationship between CHI3L1 and macrophages is crucial for disease progression. Recent research has uncovered the complex mechanisms of CHI3L1 in different diseases, highlighting its close association with macrophage functional polarization. In this article, we review recent findings regarding the various disease types and summarize the relationship between macrophages and CHI3L1. Furthermore, this article also provides a brief overview of the various mechanisms and inhibitors employed to inhibit CHI3L1 and disrupt its interaction with receptors. These endeavors highlight the pivotal roles of CHI3L1 and suggest therapeutic approaches targeting CHI3L1 in the development of metabolic diseases, neurodegenerative diseases, and cancers.

The evaluation of six genes combined value in glioma diagnosis and prognosis

PURPOSE

Glioma is the most common and fatal type of brain tumour. Owing to its aggressiveness and lethality, early diagnosis and prediction of patient survival are very important. This study aimed to identify key genes and biomarkers for glioma that can guide clinicians in making rapid diagnosis and prognostication.

METHODS

Data mining of The Cancer Genome Atlas (TCGA), Chinese Glioma Genome Atlas (CGGA), Repository of Molecular Brain Neoplasia Data, and Genotype-Tissue Expression Project brain expression data revealed significantly differentially expressed genes (DEGs), and the risk scores of individual patients were calculated. WGCNA was utilized to screen for genes most related to clinical diagnosis. Prognostic genes associated with glioma were selected via combining the LASSO regression with univariate and multivariate Cox regression and protein-protein interaction network analyses. Then, a nomogram was constructed. And CGGA dataset was utilized to validated. The protein expression levels of the signature were detected using the human protein atlas. Drug response prediction was carried out using the package "pRRophetic".

RESULTS

A six-gene signature (KLF6, CHI3L1, SERPINE1, ANGPT2, TGFBR1, and PTX3) was identified and used to stratify patients into low- and high-risk groups. Survival, ROC curve, and Cox analyses clarified that the six hub genes were a favourable independent prognostic factor for patients with glioma. A nomogram was set up by integrating clinical parameters with risk signatures, showing high precision for predicting 2-, 3-, 4-, 5-years survival. In addition, the expression of most genes was consistent with protein expression. Furthermore, the sensitivity to the top ten drugs in the GDSC database of the high-risk group was significantly higher than the low-risk group.

CONCLUSION

Based on genetic profiles and clinicopathological features, including age, grade, isocitrate dehydrogenase mutation status, we constructed a comprehensive prognostic model for patients with glioma. These signatures can be regarded as biomarkers to predict the prognosis of gliomas, possibly providing more therapeutic strategies for future clinical research.

YKL-40 immunoexpression as a prognosticator of mycosis fungoides

BACKGROUND

YKL-40 is a 40 kDa chitinase-like glycoprotein that is predicted to contribute to the pathogenesis of several inflammatory and neoplastic conditions.

OBJECTIVES

To assess YKL-40 immunoexpression in different stages of mycosis fungoides (MF) to find out if YKL-40 is playing a possible role in disease pathophysiology and progression.

METHODS

This work included 50 patients with different stages of MF diagnosed on the basis of clinical, histopathological, and both CD4 and CD8 immunophenotyping, in addition to 25 normal control skin. The Immune Reactive Score (IRS) of YKL-40 expression was determined in all specimens and statistically analyzed.

RESULTS

YKL-40 expression reported a significant rise in MF lesions compared to control skin. Among MF specimens, the mildest expression was observed in the early patch stage followed by the plaque stage, while the strongest was in tumor stages. Positive correlations were discovered between IRS of YKL-40 expression in MF specimens and patients' age, disease chronicity, clinical staging, and TNMB classification.

CONCLUSION

YKL-40 might participate in MF pathophysiology, and the highest expression is associated with advanced stages of the disease and poor outcomes. Therefore, it might be of value as a prognosticator for monitoring high-risk MF patients and follow-up assessment of treatment success.

Vascular Immune Evasion of Mesenchymal Glioblastoma Is Mediated by Interaction and Regulation of VE-Cadherin on PD-L1

The mesenchymal subtype of glioblastoma (mGBM), which is characterized by rigorous vasculature, resists anti-tumor immune therapy. Here, we investigated the mechanistic link between tumor vascularization and the evasion of immune surveillance. Clinical datasets with GBM transcripts showed that the expression of the mesenchymal markers YKL-40 (CHI3L1) and Vimentin is correlated with elevated expression of PD-L1 and poor disease survival. Interestingly, the expression of PD-L1 was predominantly found in vascular endothelial cells. Orthotopic transplantation of glioma cells GL261 over-expressing YKL-40 in mice showed increased angiogenesis and decreased CD8+ T cell infiltration, resulting in a reduction in mouse survival. The exposure of recombinant YKL-40 protein induced PD-L1 and VE-cadherin (VE-cad) expression in endothelial cells and drove VE-cad-mediated nuclear translocation of β-catenin/LEF, where LEF upregulated PD-L1 expression. YKL-40 stimulated the dissociation of VE-cad from PD-L1, rendering PD-L1 available to interact with PD-1 from CD8+-positive TALL-104 lymphocytes and inhibit TALL-104 cytotoxicity. YKL-40 promoted TALL-104 cell migration and adhesion to endothelial cells via CCR5-dependent chemotaxis but blocked its anti-vascular immunity. Knockdown of VE-cad or the PD-L1 gene ablated the effects of YKL-40 and reinvigorated TALL-104 cell immunity against vessels. In summary, our study demonstrates a novel vascular immune escape mechanism by which mGBM promotes tumor vascularization and malignant transformation.

Astrocytic Chitinase-3-like protein 1 in neurological diseases: Potential roles and future perspectives

Chitinase-3-like protein 1 (CHI3L1) is a secreted glycoprotein characterized by its ability to regulate multiple biological processes, such as the inflammatory response and gene transcriptional signaling activation. Abnormal CHI3L1 expression has been associated with multiple neurological disorders and serves as a biomarker for the early detection of several neurodegenerative diseases. Aberrant CHI3L1 expression is also reportedly associated with brain tumor migration and metastasis, as well as contributions to immune escape, playing important roles in brain tumor progression. CHI3L1 is synthesized and secreted mainly by reactive astrocytes in the central nervous system. Thus, targeting astrocytic CHI3L1 could be a promising approach for the treatment of neurological diseases, such as traumatic brain injury, ischemic stroke, Alzheimer's disease, Parkinson's disease, multiple sclerosis, amyotrophic lateral sclerosis, and glioma. Based on current knowledge of CHI3L1, we assume that it acts as a molecule mediating several signaling pathways driving the initiation and progression of neurological disorders. This narrative review is the first to introduce the potential roles of astrocytic CHI3L1 in neurological disorders. We also equally explore astrocytic CHI3L1 mRNA expression under physiological and pathological conditions. Inhibiting CHI3L1 and disrupting its interaction with its receptors through multiple mechanisms of action are briefly discussed. These endeavors highlight the pivotal roles of astrocytic CHI3L1 in neurological disorders and could contribute to the development of effective inhibitors based on the strategy of structure-based drug discovery, which could be an attractive therapeutic approach for neurological disease treatment.

High VEGFA Expression Is Associated with Improved Progression-Free Survival after Bevacizumab Treatment in Recurrent Glioblastoma

Glioblastoma (GB) is one of the deadliest human cancers. Many GB patients do not respond to treatment, and inevitably die within a median of 15-18 months post-diagnosis, highlighting the need for reliable biomarkers to aid clinical management and treatment evaluation. The GB microenvironment holds tremendous potential as a source of biomarkers; several proteins such as MMP-2, MMP-9, YKL40, and VEGFA have been identified as being differentially expressed in GB patient samples. Still to date, none of these proteins have been translated into relevant clinical biomarkers. This study evaluated the expression of MMP-2, MMP-9, YKL40, and VEGFA in a series of GBs and their impact on patient outcome. High levels of VEGFA expression were significantly associated with improved progression-free survival after bevacizumab treatment, thus having potential as a tissue biomarker for predicting patients' response to bevacizumab. Noteworthily, VEGFA expression was not associated with patient outcome after temozolomide treatment. To a lesser extent, YKL40 also provided significant information regarding the extent of bevacizumab treatment. This study highlights the importance of studying secretome-associated proteins as GB biomarkers and identifies VEGFA as a promising marker for predicting response to bevacizumab.

Chitotriosidase and Neopterin as Two Novel Potential Biomarkers for Advanced Stage and Survival Prediction in Gastric Cancer—A Pilot Study

Gastric cancer is the fifth type of neoplasia most frequently diagnosed and the fourth cause of death among other cancers. Prevalence is around two times higher for males than females. Chitotriosidase and neopterin are two molecular biomarkers with potential diagnostic and prognostic use in malignant pathology. We conducted a longitudinal prospective cohort study on thirty-nine patients with gastric adenocarcinoma, with a male-to-female ratio of 1.78 and an average age of 64.3 ± 9.97 years. No statistically significant differences in biomarker levels at presentation were observed between curative-intent surgery (28 patients) and advanced cases, suited only for palliative procedures (11 patients). Biomarker values were not significantly different for the advanced T stage and the presence of metastasis (p > 0.05—Mann Whitney test). The patients that died in the first 30 days after surgery did not present significantly different values at baseline, in comparison with those that had longer survival times, though a significant cut-off value was observed for chitotriosidase activity at 310 nmol/mL/h [AUC (area under the curve) = 0.78; 95% CI (0.61–0.92)]. The cut-off values corresponding to death after the first year, tumor invasion, and metastasis were not statistically significant. In the COX multivariate model, neopterin did not validate itself as a prognostic biomarker, however, chitotriosidase activity before surgery was significantly associated with overall survival (HR = 1.0038, p = 0.03). We conclude that chitotriosidase may have the potential to improve the prognostic model for gastric adenocarcinoma.

Do Elevated YKL-40 Levels Drive the Immunosuppressive Tumor Microenvironment in Colorectal Cancer? Assessment of the Association of the Expression of YKL-40, MMP-8, IL17A, and PD-L1 with Coexisting Type 2 Diabetes, Obesity, and Active Smoking

The influence of chitinase-3-like protein 1 (YKL-40 or CHI3L1) expression on the immunological properties of the tumor microenvironment, which may affect the effectiveness of immunotherapy, is currently not sufficiently understood in colorectal cancer (CRC). The aim of this study was to investigate the relationship between YKL-40 expression and the immunological properties of the tumor microenvironment in CRC. We performed in silico analysis, including analysis of immune cell infiltration scores and the immune landscape depending on YKL-40 expression, gene set enrichment analysis (GSEA), and analysis of three Gene Expression Omnibus (GEO) datasets. In 48 CRC tissue homogenates and the surgical margin, we analyzed the expression of YKL-40, MMP8, IL17A, and PD-L1. Moreover, we analyzed the expression of YKL-40 in tissue homogenates retrieved from patients with coexisting diabetes, obesity, and smoking. The expression of YKL-40 was significantly higher in CRC tumor tissue compared to healthy tissue and correlated with MMP-8, IL17A, and PD-L1 expression. In silico analysis revealed an association of YKL-40 with disease recurrence, and GSEA revealed a potential link between elevated YKL-40 expression and immunosuppressive properties of the tumor microenvironment in CRC.

Multimodal study of CHI3L1 inhibition and its effect on angiogenesis, migration, immune response and refractive index of cellular structures in glioblastoma

Glioblastoma is one of the most aggressive tumours with a poor response to treatment and a poor prognosis for patients. One of the proteins expressed in glioblastoma tissue is CHI3L1 (YKL-40), which is upregulated and known for its angiogenesis-supporting and pro-tumour immunomodulatory effects in a variety of cancers. In this paper we present the anti-angiogenic, anti-migratory and immunomodulatory effects of the compound G721-0282, an inhibitor of CHI3L1. The inhibitor-induced changes were investigated using conventional techniques as well as the novel label-free digital holographic tomography (DHT), a quantitative phase imaging technique that allows the reconstruction of the refractive index (RI), which is used as an image contrast for 3D visualisation of living cells. DHT allowed digital staining of individual cells and intercellular structures based only on their specific RI. Quantitative spatially resolved analysis of the RI data shows that the concentration of G721-0282 leads to significant changes in the density of cells and their intracellular structures (in particular the cytoplasm and nucleus), in the volume of lipid droplets and in protein concentrations. Studies in the U-87 MG glioblastoma cell line, THP-1 monocytes differentiated into macrophages, human microvascular endothelial cells (HMEC-1) and in the spheroid model of glioblastoma composed of U-87 MG, HMEC-1 and macrophages suggest that inhibition of CHI3L1 may have potential in the antitumour treatment of glioblastoma. In this paper, we also propose a spheroid model for in vitro studies that mimics this type of tumour.

Extracellular matrix remodeling in tumor progression and immune escape: from mechanisms to treatments

The malignant tumor is a multi-etiological, systemic and complex disease characterized by uncontrolled cell proliferation and distant metastasis. Anticancer treatments including adjuvant therapies and targeted therapies are effective in eliminating cancer cells but in a limited number of patients. Increasing evidence suggests that the extracellular matrix (ECM) plays an important role in tumor development through changes in macromolecule components, degradation enzymes and stiffness. These variations are under the control of cellular components in tumor tissue via the aberrant activation of signaling pathways, the interaction of the ECM components to multiple surface receptors, and mechanical impact. Additionally, the ECM shaped by cancer regulates immune cells which results in an immune suppressive microenvironment and hinders the efficacy of immunotherapies. Thus, the ECM acts as a barrier to protect cancer from treatments and supports tumor progression. Nevertheless, the profound regulatory network of the ECM remodeling hampers the design of individualized antitumor treatment. Here, we elaborate on the composition of the malignant ECM, and discuss the specific mechanisms of the ECM remodeling. Precisely, we highlight the impact of the ECM remodeling on tumor development, including proliferation, anoikis, metastasis, angiogenesis, lymphangiogenesis, and immune escape. Finally, we emphasize ECM "normalization" as a potential strategy for anti-malignant treatment.

Gal-1 Expression Analysis in the GLIOCAT Multicenter Study: Role as a Prognostic Factor and an Immune-Suppressive Biomarker

Glioblastoma (GBM) is the most frequent primary malignant brain tumor and has a dismal prognosis. Unfortunately, despite the recent revolution of immune checkpoint inhibitors in many solid tumors, these have not shown a benefit in overall survival in GBM patients. Therefore, new potential treatment targets as well as diagnostic, prognostic, and/or predictive biomarkers are needed to improve outcomes in this population. The β-galactoside binding protein Galectin-1 (Gal-1) is a protein with a wide range of pro-tumor functions such as proliferation, invasion, angiogenesis, and immune suppression. Here, we evaluated Gal-1 expression by immunohistochemistry in a homogenously treated cohort of GBM (the GLIOCAT project) and correlated its expression with clinical and molecular data. We observed that Gal-1 is a negative prognostic factor in GBM. Interestingly, we observed higher levels of Gal-1 expression in the mesenchymal/classical subtypes compared to the less aggressive proneural subtype. We also observed a Gal-1 expression correlation with immune suppressive signatures of CD4 T-cells and macrophages, as well as with several GBM established biomarkers, including SHC1, PD-L1, PAX2, MEOX2, YKL-40, TCIRG1, YWHAG, OLIG2, SOX2, Ki-67, and SOX11. Moreover, Gal-1 levels were significantly lower in grade 4 IDH-1 mutant astrocytomas, which have a better prognosis. Our results confirm the role of Gal-1 as a prognostic factor and also suggest its value as an immune-suppressive biomarker in GBM.

Imaginal disk growth factors are Drosophila chitinase-like proteins with roles in morphogenesis and CO2 response

Chitinase-like proteins (CLPs) are members of the family 18 glycosyl hydrolases, which include chitinases and the enzymatically inactive CLPs. A mutation in the enzyme's catalytic site, conserved in vertebrates and invertebrates, allowed CLPs to evolve independently with functions that do not require chitinase activity. CLPs normally function during inflammatory responses, wound healing, and host defense, but when they persist at excessive levels at sites of chronic inflammation and in tissue-remodeling disorders, they correlate positively with disease progression and poor prognosis. Little is known, however, about their physiological function. Drosophila melanogaster has 6 CLPs, termed Imaginal disk growth factors (Idgfs), encoded by Idgf1, Idgf2, Idgf3, Idgf4, Idgf5, and Idgf6. In this study, we developed tools to facilitate characterization of the physiological roles of the Idgfs by deleting each of the Idgf genes using the CRISPR/Cas9 system and assessing loss-of-function phenotypes. Using null lines, we showed that loss of function for all 6 Idgf proteins significantly lowers viability and fertility. We also showed that Idgfs play roles in epithelial morphogenesis, maintaining proper epithelial architecture and cell shape, regulating E-cadherin and cortical actin, and remarkably, protecting these tissues against CO2 exposure. Defining the normal molecular mechanisms of CLPs is a key to understanding how deviations tip the balance from a physiological to a pathological state.

YKL-40 as a possible marker of neutrophilic asthma

Asthma is a heterogeneous chronic disorder of the airways, with inflammation and bronchial hyperresponsiveness as its major underlying phenomena. Asthmatics vary in terms of inflammation pattern, concomitant pathologies, and factors aggravating the course of the disease. As a result, there is a need for sensitive and specific biomarkers that could facilitate diagnosing asthma as well as phenotyping in everyday practice. Chitinases and chitinase-like proteins (CLPs) seem promising in this field. Chitinases are evolutionarily conserved hydrolases that degrade chitin. In contrast, CLPs bind chitin but do not have degrading activity. Mammalian chitinases and CLPs are produced by neutrophils, monocytes, and macrophages in response to parasitic or fungal infections. Recently, several questions have been raised about their role in chronic airway inflammation. Several studies demonstrated that overexpression of CLP YKL-40 was associated with asthma. Moreover, it correlated with exacerbation rate, therapy resistance, poor control of symptoms, and, inversely, with FEV₁. YKL-40 facilitated allergen sensitization and IgE production. Its concentration was elevated in bronchoalveolar lavage fluid after an allergen challenge. It was also found to promote the proliferation of bronchial smooth muscle cells and correlate with subepithelial membrane thickness. Thus, it may be involved in bronchial remodeling. Associations between YKL-40 and particular asthma phenotypes remain unclear. Some studies showed that YKL-40 correlates with blood eosinophilia and FeNO, suggesting a role in T2-high inflammation. Quite the opposite, cluster analyses revealed the highest upregulation in severe neutrophilic asthma and obesity-associated asthma. The main limitation in the practical application of YKL-40 as a biomarker is its low specificity. High serum levels of YKL-40 were also found in COPD and several malignancies, in addition to infectious and autoimmune diseases. To conclude, the level of YKL-40 correlates with asthma and some clinical features in the whole asthmatic population. The highest levels are found in neutrophilic and obesity-related phenotypes. However, due to its low specificity, the practical application of YKL-40 remains uncertain but could be useful in phenotyping, especially when combined with other biomarkers.

Functional analysis of the short splicing variant encoded by CHI3L1/YKL-40 in glioblastoma

The glycoprotein YKL-40 has been well studied as a serum biomarker of prognosis and disease status in glioblastoma. YKL-40 is a chitinase-like protein with defective chitinase activity that plays an important role in promoting cell proliferation, migration, and metastasis in glioblastoma multiforme (GBM). The short variant (SV) of YKL-40, generated by an alternative splicing event that splices out exon 8, was reported in the early developing human musculoskeletal system, although its role in GBM is still unknown. Our results showed that individual glioblastoma cell lines displayed increased expression of the short variant of YKL-40 after low serum treatment. In addition, unlike the full-length (FL) version, which was localized to all cell compartments, the short isoform could not be secreted and was localized only to the cytoplasm. Functionally, FL YKL-40 promoted cell proliferation and migration, whereas SV YKL-40 suppressed them. Transcriptome analysis revealed that these opposing roles of the two isoforms may be modulated by differentially regulating several oncogenic-related pathways, including p53, the G2/M checkpoint, and MYC-related signaling. This study may provide new ideas for the development of targeted anti-YKL-40 therapy in GBM treatment.

Develop companion radiopharmaceutical YKL40 antibodies as potential theranostic agents for epithelial ovarian cancer

Epithelial ovarian cancer (EOC) is usually diagnosed at an advanced stage and has poor prognosis. Theranostic agents are the current trend in drug development, but are lacking in EOC. YKL40 is predominantly expressed and involved in tumorigenesis in EOC. In this study, we developed a companion theranostic agent targeting YKL40. We measured YKL40 expression levels in ascites using ELISA and correlated them with the clinical outcomes of patients with EOC. We developed radionuclide labeled In-111/Lu-177-DTPA-YKL40 neutralizing antibodies and investigated their radiochemical purity, SPECT/CT imaging, bio-distribution, and therapeutic responses in ovarian cancer xenograft mice. We demonstrated that YKL40 expression levels in ascites were significantly higher in EOC patients with serous histological type, high tumor grade, advanced stage, tumor recurrence, chemoresistance, and tumor-related death. The radiochemical purity of In-111/Lu-177-DTPA-YKL40 neutralizing antibodies reached more than 90% after 24 h of labeling. SPECT/CT imaging showed significant accumulation of In-111-DTPA-YKL40 and Lu-177-DTPA-YKL40 antibodies at the tumor site of ovarian cancer xenograft mice 24 h after administration. Lu-177-DTPA-YKL40 antibodies significantly inhibited tumor growth in ovarian cancer xenograft mice. Our study indicated that In-111/Lu-177-DTPA-YKL40 neutralizing antibodies could be potential companion theranostic agents for patients with EOC.

A new biomarker to enhance the radiosensitivity of hepatocellular cancer: miRNAs

Aims: This review summarizes findings regarding miRNAs that modulate radiation in hepatocellular carcinoma (HCC) and evaluates their potential clinical therapeutic uses. Materials & methods: We searched the relevant English-language medical databases for papers on miRNAs and radiation therapy for tumors to identify miRNAs that are linked with radiosensitivity and radioresistance, focusing on those associated with HCC radiation. Results: There were 88 papers assessed for miRNAs associated with tumor radiation, 56 of which dealt with radiosensitization, 21 with radioresistance and 11 with radiosensitization for HCC. Conclusion: Further work in this area would enable future evaluation of radiation responses and the potential use of miRNAs as therapeutic agents in HCC patients.

The Modeling Analysis and Effect of CHI3L1 and CD31-Marked Microvessel Density in the Occurrence and Development of Cervical Squamous Cell Carcinoma

Background

Chitinase-3-like protein 1 (CHI3Ll) has been identified as a novel tumor marker in several cancers. The objective of this study was to detect the expression of Chitinase-3-like protein 1 (CHI3L1) and CD31-labeled microvessel density (MVD) in cervical squamous cell carcinoma (CSCC) and to assess its prognostic impact.

Methods

Elivision™ plus immunohistochemical method was used to detect CHI3L1 expression and MVD in different cervical tissues. We analyzed the relationship between CHI3L1 and MVD in CSCC tissues and investigated the relationship between CHI3L1, MVD, and clinicopathological parameters. Univariate and multivariate survival analyses were performed to assess the impact on progression-free survival (PFS) and overall survival (OS).

Results

The positive expression rate of CHI3L1 protein in CSCC tissues (69.9%, 72/103) was significantly higher than that in high-grade cervical intraepithelial lesions (53.3%, 32/60), low-grade cervical intraepithelial lesions (25%, 15/60), and normal cervical tissues (16.7%, 10/60). MVD values ranged from 6 to 64 in CSCC, and no microvascular formation was observed in normal cervical tissues, high-grade intraepithelial lesions, or low-grade intraepithelial lesions. The high expression of CHI3L1 and MVD was significantly correlated with the invasion depth, differentiation degree, vascular invasion, and lymph node metastasis of CSCC (all P < 0.05). In CSCC, the expression of MVD in the CHI3L1 high-expression group (41.35 ± 9.056) was significantly higher than that in the CHI3L1 low-expression group (23.26 ± 11.000, P < 0.05). On univariate Kaplan–Meier analysis, FIGO stage, tumor diameter, lymph node metastasis, vascular invasion, CHI3L1, and MVD of CSCC were related to the prognosis of PFS and OS (all P < 0.05); however, CHI3L1 and MVD were not independent prognostic factors.

Conclusion

CHI3L1 may be involved in the progression of cervical cancer. Its high expression can promote neovascularization in the tumor microenvironment. CHI3L1 is a potential therapeutic target in the context of cervical cancer.

Emerging Biomarkers of Multiple Sclerosis in the Blood and the CSF: A Focus on Neurofilaments and Therapeutic Considerations

INTRODUCTION

Multiple Sclerosis (MS) is the most common immune-mediated chronic neurodegenerative disease of the central nervous system (CNS) affecting young people. This is due to the permanent disability, cognitive impairment, and the enormous detrimental impact MS can exert on a patient's health-related quality of life. It is of great importance to recognise it in time and commence adequate treatment at an early stage. The currently used disease-modifying therapies (DMT) aim to reduce disease activity and thus halt disability development, which in current clinical practice are monitored by clinical and imaging parameters but not by biomarkers found in blood and/or the cerebrospinal fluid (CSF). Both clinical and radiological measures routinely used to monitor disease activity lack information on the fundamental pathophysiological features and mechanisms of MS. Furthermore, they lag behind the disease process itself. By the time a clinical relapse becomes evident or a new lesion appears on the MRI scan, potentially irreversible damage has already occurred in the CNS. In recent years, several biomarkers that previously have been linked to other neurological and immunological diseases have received increased attention in MS. Additionally, other novel, potential biomarkers with prognostic and diagnostic properties have been detected in the CSF and blood of MS patients.

AREAS COVERED

In this review, we summarise the most up-to-date knowledge and research conducted on the already known and most promising new biomarker candidates found in the CSF and blood of MS patients.

DISCUSSION

the current diagnostic criteria of MS relies on three pillars: MRI imaging, clinical events, and the presence of oligoclonal bands in the CSF (which was reinstated into the diagnostic criteria by the most recent revision). Even though the most recent McDonald criteria made the diagnosis of MS faster than the prior iteration, it is still not an infallible diagnostic toolset, especially at the very early stage of the clinically isolated syndrome. Together with the gold standard MRI and clinical measures, ancillary blood and CSF biomarkers may not just improve diagnostic accuracy and speed but very well may become agents to monitor therapeutic efficacy and make even more personalised treatment in MS a reality in the near future. The major disadvantage of these biomarkers in the past has been the need to obtain CSF to measure them. However, the recent advances in extremely sensitive immunoassays made their measurement possible from peripheral blood even when present only in minuscule concentrations. This should mark the beginning of a new biomarker research and utilisation era in MS.

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

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

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

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

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

The Diagnostic value of Serum YKL-40 in Endometrial Cancer: a meta-analysis

BACKGROUND

Serum YKL-40 is a promising noninvasive biomarker for the early diagnosis of endometrial cancer (EC), but its value is disputed.

OBJECTIVE

To investigate the serum YKL-40 in the early diagnostic value of EC.

METHODS

Databases were systematically searched again before April 2021 and 14 studies were finally included in this meta-analysis. Pooled sensitivity, specificity, negative likelihood ratio (NLR), positive likelihood ratio (PLR), diagnostic odds ratio (DOR), and summary receiver operating characteristic (SROC) curve analyses were assessed. This meta-analysis investigated the source of heterogeneity using sensitivity analysis, subgroup analysis, and meta-regression.

RESULTS

Databases were systematically searched again before April 2021 and 14 studies were finally included in this meta-analysis. First, the SROC curve presented an area under the curve (AUC) of 0.853 (SE =0.0213) for YKL-40 alone and an AUC of 0.946 (SE =0.0268) for YKL-40 combined with other biomarkers. Second, diagnostic types might be related to the diagnostic accuracy and is a significant source of heterogeneity (P = 0.035).

CONCLUSION

Serum YKL-40 helped diagnose EC, and its combination with other biomarkers was better than itself alone.

Chitinase 3-like 1 secreted from cancer-associated fibroblasts promotes tumor angiogenesis via interleukin-8 secretion in colorectal cancer

The cancer‑stromal interaction has been demonstrated to promote tumor progression, and cancer-associated fibroblasts (CAFs), which are the main components of stromal cells, have attracted attention as novel treatment targets. Chitinase 3-like 1 (CHI3L1) is a chitinase-like protein, which affects cell proliferation and angiogenesis. However, the mechanisms through which cells secrete CHI3L1 and through which CHI3L1 mediates tumor progression in the cancer microenvironment are still unclear. Accordingly, the present study assessed the secretion of CHI3L1 in the microenvironment of colorectal cancer and evaluated how CHI3L1 affects tumor angiogenesis. CAFs and normal fibroblasts (NFs) established from colorectal cancer tissue, and human colon cancer cell lines were evaluated using immunostaining, cytokine antibody array, RNA interference, reverse transcription-quantitative PCR (RT-qPCR), ELISA, western blotting and angiogenesis assays. The expression and secretion of CHI3L1 in CAFs were stronger than those in NFs and colorectal cancer cell lines. In addition, interleukin-13 receptor α2 (IL-13Rα2), a receptor for CHI3L1, was not expressed in colorectal cancer cell lines, but was expressed in fibroblasts, particularly CAFs. Furthermore, the expression and secretion of IL-8 in CAFs was stronger than that in NFs and cancer cell lines, and recombinant CHI3L1 addition increased IL-8 expression in CAFs, whereas knockdown of CHI3L1 suppressed IL-8 expression. Furthermore, IL-13Rα2 knockdown suppressed the enhancement of IL-8 expression induced by CHI3L1 treatment in CAFs. For vascular endothelial growth factor-A (VEGFA), similar results to IL-8 were observed in an ELISA for comparison of secretion between CAFs and NFs and for changes in secretion after CHI3L1 treatment in CAFs; however, no significant differences were observed for changes in expression after CHI3L1 treatment or IL-13Rα2 knockdown in CAFs assessed using RT-qPCR assays. Angiogenesis assays revealed that tube formation in vascular endothelial cells was suppressed by conditioned medium from CAFs with the addition of human CHI3L1 neutralizing antibodies compared with control IgG, and also suppressed by conditioned medium from CAFs transfected with CHI3L1, IL-8 or VEGFA small interfering RNA compared with negative control small interfering RNA. Overall, the present findings indicated that CHI3L1 secreted from CAFs acted on CAFs to increase the secretion of IL-8, thereby affecting tumor angiogenesis in colorectal cancer.

YKL-40 promotes invasion and metastasis of bladder cancer by regulating epithelial mesenchymal transition

OBJECTIVE

This study aims to explore the relevance between YKL-40 and recurrence and progression of bladder cancer, and determine whether YKL-40 can be used as a potential target in patients with bladder cancer.

METHODS

We analyzed the invasion and metastasis ability of BIU-87, UMUC3, J82, T24, 5637 and immortalized human bladder epithelial cells SVHUC1 by Transwell method. The YKL-40 expression levels in cell lines were analyzed by Western blot and qPCR.

RESULTS

The increase of YKL-40 level, especially in tumour group, was related to tumour pathological stage and tumour invasion and metastasis. The cell lines with YKL-40 high expression had stronger invasion and metastasis ability. Overexpression of YKL-40 in SVHUC1 with the lowest YKL-40 expression can enhance the invasion and migration of cells. In T24 cells with YKL-40 high expression, transfection of shRNA plasmid targeting YKL-40 can down regulate the invasion and migration. The expression levels of N-cadherin and Vimentin in YKL-40 overexpressed SVHUC1 cells were increased, the E-cadherin expression was decreased, the Twist, Snail and Slug expression levels were increased, but they were opposite in T24 cells with down-regulation of YKL-40 expression.

CONCLUSIONS

YKL-40 promoted the migration and invasion of bladder cancer cells by up regulating the EMT gene expression. The YKL-40 expression is closely related to the invasion and migration of bladder cancer.

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.

YKL-40 and neuron-specific enolase in neurodegeneration and neuroinflammation

Neurodegenerative diseases comprise a large number of disorders with high impact on human health. Neurodegenerative processes are caused by various etiological factors and differ in their clinical presentation. Neuroinflammation is widely discussed as both a cause and a consequence in the manifestation of these disorders. The interplay between the two entities is considered as a major contributor to the ongoing disease progression. An attentive search and implementation of new and reliable markers specific for the processes of inflammation and degeneration is still needed. YKL-40 is a secreted glycoprotein produced by activated glial cells during neuroinflammation. Neuron-specific enolase (NSE), expressed mainly by neuronal cells, is a long-standing marker for neuronal damage. The aim of this review is to summarize, clarify, and evaluate the potential significance and relationship between YKL-40 and NSE as biomarkers in the monitoring and prognosis of a set of neurological diseases, such as Alzheimer's disease, Parkinson's disease, Huntington's disease, and multiple sclerosis. YKL-40 appears to be a more reliable biomarker in neurological diseases than NSE. The more prominent expression pattern of YKL-40 could be explained with the more obvious involvement of glial cells in pathological processes accompanying each neurodegenerative disease, whereas reduced NSE levels are likely related to low metabolic activity and increased death of neurons.

Knockdown of YKL-40 inhibits angiogenesis through regulation of VEGF/VEGFR2 and ERK1/2 signaling in endometrial cancer

Studies have demonstrated that small interfering RNA (siRNA) targeting YKL-40 (siYKL-40) inhibits the proliferation, migration, invasion, and induces antiapoptotic abilities of endometrial cancer (EC) HEC-1A cells. However, its effect on angiogenesis is unclear. The present study aimed to investigate the role of YKL-40 in endometrial cancer and the related molecular mechanisms. YKL-40 was knocked down by transfection with siYKL-40 and the effects on angiogenesis, cell viability, and signaling pathways were investigated. The results showed that siYKL-40 inhibited VEGFA levels and tube formation in endothelial cells. Additionally, inhibition of YKL-40 decreased the expression levels of vascular endothelial growth factor (VEGF), phosphorylated vascular endothelial growth factor receptor 2 (pVEGFR2), and phosphorylated extracellular signal-regulated kinases 1 and 2 (pERK1/2). Furthermore, a nude mice xenograft model of EC showed that siYKL-40 inhibited tumor growth. Inhibition of YKL-40 led to suppression of angiogenesis and reduction of microvessel density through VEGF/VEGFR2 and ERK1/2 signaling in endometrial cancer cells. Taken together, this study demonstrated novel molecular mechanisms for role of YKL-40 in EC.

Mutant IDH1 inhibitors activate pSTAT3-Y705 leading to an increase in BCAT1 and YKL-40 levels in mutant IDH1-expressing cells

IDH1 mutations are frequent and early events in gliomas. Mutant IDH1 produces D-2HG that causes epigenetic changes by increasing histone and DNA methylations, thereby contributing to tumor growth. Mutant IDH1 rewires metabolism and endows a few therapeutic vulnerabilities in cells. But, mutant IDH1 inhibitor(s) treatments reverse these therapeutic vulnerabilities by increasing cell growth. Nevertheless, it is unclear how mutant IDH1 inhibitor(s) increases cell growth. As mutant IDH1 inhibitor(s) increase cell growth, therefore we asked whether mutant IDH1 inhibitor(s) activate oncogenes in mutant IDH1-expressing cells. To answer this question, we used allosteric mutant IDH1 inhibitors to treat mutant IDH1-expressing HT1080 cells, and examined for activation of oncogenes by assessing the levels of our read-outs: BCAT1 and YKL-40. We found that mutant IDH1 inhibitors' treatments increased BCAT1 and YKL-40 levels in HT1080 cells. Next, we observed that mutant IDH1 inhibitors activated STAT3 by phosphorylation at Tyr-705 position (pSTAT3-Y705) and its nuclear translocation. Upon examining the molecular mechanism of pSTAT3-Y705 activation in mutant IDH1 inhibitor-treated cells, we found that mutant IDH1 strongly bound STAT3, but mutant IDH1 inhibitor treatment decreased mutant IDH1-STAT3 binding. Furthermore, we observed that STAT3-knockdown and pharmacological inhibition of STAT3 attenuated the mutant IDH1 inhibitor-mediated increase in BCAT1 and YKL-40 levels, whereas STAT3 overexpression and Interleukin-6 (STAT3 activator) treatments increased BCAT1 and YKL-40 levels. We conclude that mutant IDH1 inhibitors activate the oncogenic transcription factor-STAT3 leading to an increase in BCAT1 and YKL-40 levels in mutant IDH1-expressing cells.

Blood-based protein biomarkers in bladder urothelial tumors

Bladder cancer (BC) is the fifth most common cancer with a high prevalence rate. It is classically classified in two groups, namely non-muscle invasive (NMIBC) and muscle invasive (MIBC). NMIBC accounts for 75% of cases and has a better prognosis than MIBC. However, 30-50% of the NMIBC patients will show recurrences throughout their lives, and about 10-20% of them will progress to MIBC, with frequent metastasis and a reduced survival rate. The diagnosis of bladder cancer is confirmed by direct visualization of the tumour and other mucosal abnormalities with endoscopic excision using cystoscopy and transurethral resection of the bladder (TURBT). An adequate TURBT requires complete resection of all visible tumour with appropriate sampling of the bladder to assess the depth of invasion. However, for many years, researchers have attempted to identify and utilise urinary markers for bladder cancer detection. Voided urine cytology has been the mainstay of urine-based diagnosis of bladder cancer since originally described by Papanicolau and Marshall. Nonetheless, urine cytology has several drawbacks, including a poor sensitivity for low-grade/stage tumours, a lack of interobserver consistency and a variable range of readings (e.g., atypical, atypical-suspicious, non-diagnostic). These shortcomings have inspired the search for more sensitive bladder cancer biomarkers. To bring precision medicine to genitourinary oncology, the analysis of the plasma/serum wide genome and proteome offers promising possibilities.

Elevated YKL-40 serum levels may contribute to wet age-related macular degeneration via the ERK1/2 pathway

Choroidal neovascularization (CNV) is a key characteristic of wet age-related macular degeneration (AMD) that can lead to severe vision loss in the elderly. Anti-VEGF therapy is currently the premier strategy for wet AMD, but it has limited efficacy. Previous studies have shown that chitinase-3-like-1 (YKL-40) can promote microangiogenesis and inflammation, but its effect on CNV formation has not yet been studied. Here, we investigated the potential role of YKL-40 in wet AMD and the underlying mechanism(s). We report that the serum expression of YKL-40 in wet AMD patients was significantly higher than that in control patients and was positively correlated with VEGF expression, indicating that YKL-40 may participate in the development of wet AMD. In addition, YKL-40 and VEGF expression levels were observed to be increased and the ERK1/2 pathway activated in the neuroretinal (NR) and RPE/choroid tissues of mice with laser-induced CNV. The YKL-40 and phosphorylated protein levels of the ERK1/2 pathway were decreased after intravitreal injection with an anti-YKL-40 antibody, suggesting that anti-YKL-40 could inhibit the activation of the ERK1/2 pathway. These results indicate that YKL-40 may serve as a novel target for the diagnosis and treatment of wet AMD.