Suppression of metastasis through inhibition of chitinase 3-like 1 expression by miR-125a-3p-mediated up-regulation of USF1

Inhibition of Amyloid-β (Aβ)-Induced Cognitive Impairment and Neuroinflammation in CHI3L1 Knockout Mice through Downregulation of ERK-PTX3 Pathway

Several clinical studies reported that the elevated expression of Chitinase-3-like 1 (CHI3L1) was observed in patients suffering from a wide range of diseases: cancer, metabolic, and neurological diseases. However, the role of CHI3L1 in AD is still unclear. Our previous study demonstrated that 2-({3-[2-(1-Cyclohexen-1-yl)ethyl]-6,7-dimethoxy-4-oxo-3,4-dihydro-2-quinazolinyl}culfanyl)-N-(4-ethylphenyl)butanamide, a CHI3L1 inhibiting compound, alleviates memory and cognitive impairment and inhibits neuroinflammation in AD mouse models. In this study, we studied the detailed correlation of CHI3L1 and AD using serum from AD patients and using CHI3L1 knockout (KO) mice with Aβ infusion (300 pmol/day, 14 days). Serum levels of CHI3L1 were significantly elevated in patients with AD compared to normal subjects, and receiver operating characteristic (ROC) analysis data based on serum analysis suggested that CHI3L1 could be a significant diagnostic reference for AD. To reveal the role of CHI3L1 in AD, we investigated the CHI3L1 deficiency effect on memory impairment in Aβ-infused mice and microglial BV-2 cells. In CHI3L1 KO mice, Aβ infusion resulted in lower levels of memory dysfunction and neuroinflammation compared to that of WT mice. CHI3L1 deficiency selectively inhibited phosphorylation of ERK and IκB as well as inhibition of neuroinflammation-related factors in vivo and in vitro. On the other hand, treatment with recombinant CHI3L1 increased neuroinflammation-related factors and promoted phosphorylation of IκB except for ERK in vitro. Web-based gene network analysis and our results showed that CHI3L1 is closely correlated with PTX3. Moreover, in AD patients, we found that serum levels of PTX3 were correlated with serum levels of CHI3L1 by Spearman correlation analysis. These results suggest that CHI3L1 deficiency could inhibit AD development by blocking the ERK-dependent PTX3 pathway.

Chitin-mediated blockade of chitinase-like proteins reduces tumor immunosuppression, inhibits lymphatic metastasis and enhances anti-PD-1 efficacy in complementary TNBC models

BACKGROUND

Chitinase-like proteins (CLPs) play a key role in immunosuppression under inflammatory conditions such as cancer. CLPs are enzymatically inactive and become neutralized upon binding of their natural ligand chitin, potentially reducing CLP-driven immunosuppression. We investigated the efficacy of chitin treatment in the context of triple-negative breast cancer (TNBC) using complementary mouse models. We also evaluated the immunomodulatory influence of chitin on immune checkpoint blockade (ICB) and compared its efficacy as general CLP blocker with blockade of a single CLP, i.e. chitinase 3-like 1 (CHI3L1).

METHODS

Female BALB/c mice were intraductally injected with luciferase-expressing 4T1 or 66cl4 cells and systemically treated with chitin in combination with or without anti-programmed death (PD)-1 ICB. For single CLP blockade, tumor-bearing mice were treated with anti-CHI3L1 antibodies. Metastatic progression was monitored through bioluminescence imaging. Immune cell changes in primary tumors and lymphoid organs (i.e. axillary lymph nodes and spleen) were investigated through flow cytometry, immunohistochemistry, cytokine profiling and RNA-sequencing. CHI3L1-stimulated RAW264.7 macrophages were subjected to 2D lymphatic endothelial cell adhesion and 3D lymphatic integration in vitro assays for studying macrophage-mediated lymphatic remodeling.

RESULTS

Chitin significantly reduced primary tumor progression in the 4T1-based model by decreasing the high production of CLPs that originate from tumor-associated neutrophils (TANs) and Stat3 signaling, prominently affecting the CHI3L1 and CHI3L3 primary tumor levels. It reduced immunosuppressive cell types and increased anti-tumorigenic T-cells in primary tumors as well as axillary lymph nodes. Chitin also significantly reduced CHI3L3 primary tumor levels and immunosuppression in the 66cl4-based model. Compared to anti-CHI3L1, chitin enhanced primary tumor growth reduction and anti-tumorigenicity. Both treatments equally inhibited lymphatic adhesion and integration of macrophages, thereby hampering lymphatic tumor cell spreading. Upon ICB combination therapy, chitin alleviated anti-PD-1 resistance in both TNBC models, providing a significant add-on reduction in primary tumor and lung metastatic growth compared to chitin monotherapy. These add-on effects occurred through additional increase in CD8α+ T-cell infiltration and activation in primary tumor and lymphoid organs.

CONCLUSIONS

Chitin, as a general CLP blocker, reduces CLP production, enhances anti-tumor immunity as well as ICB responses, supporting its potential clinical relevance in immunosuppressed TNBC patients.

USF1 modulates transcription and cellular functions by regulating multiple transcription factors in Huh7 cells

Liver cancer, including hepatocellular carcinoma (HCC), is a malignant tumor that has high rates of metastasis and mortality worldwide. Upstream transcription factor 1 (USF1) is a canonical transcription factor (TF) and is associated with the pathogenesis of several cancers, but its biological functions and molecular targets in HCC remain unclear. Huh7 cells that overexpress USF1 were used with whole transcriptome profiling through RNA sequencing and chromatin immunoprecipitation (ChIP) sequencing methods to investigate the downstream targets of USF1. Reverse transcription-quantitative PCR was then used to validate the downstream targets. The results showed that USF1 significantly regulates 350 differentially expressed genes (DEGs). The upregulated DEGs were primarily protein-coding genes enriched in immune and inflammation response pathways, while the downregulated DEGs were mainly coding long non-coding (lnc)RNAs, indicating the regulatory function of USF1. It was also demonstrated that USF1 directly binds to the promoter region of 2,492 genes, which may be involved in the viral progression and cell proliferation pathways. By integrating these two datasets, 16 overlapped genes were detected, including downregulated lncRNA-NEAT1 and upregulated TF-ETV5. The downregulated lncRNA-NEAT1 showed reverse expression pattern and prognosis result compared with that of USF1 in patients with liver cancer, while upregulated TF-ETV5 showed consistent results with USF1. Promoter region motif analysis indicated that ETV5 has more binding motifs and genes than USF1 itself for USF1-regulated DEGs, indicating that USF1 may indirectly modulate gene expression by regulating ETV5 expression in Huh7 cells. The study also validated the direct interaction between USF1 and the promoter of ETV5 using ChIP-qPCR. In summary, the results demonstrated that USF1 binds to the promoter region of thousands of genes and affects a large part of DEGs indirectly. Downstream genes, including lncRNA-NEAT1 and TF-ETV5, may also have potential functions in the regulated network by USF1 and have potential functions in the progression of HCC. The present findings suggested that USF1 and its downstream targets could be potential targets for HCC therapy in the future.

Recent advances on high-efficiency of microRNAs in different types of lung cancer: a comprehensive review

Carcinoma of the lung is among the most common types of cancer globally. Concerning its histology, it is categorized as a non-small cell carcinoma (NSCLC) and a small cell cancer (SCLC) subtype. MicroRNAs (miRNAs) are a member of non-coding RNA whose nucleotides range from 19 to 25. They are known to be critical regulators of cancer via epigenetic control of oncogenes expression and by regulating tumor suppressor genes. miRNAs have an essential function in a tumorous microenvironment via modulating cancer cell growth, metastasis, angiogenesis, metabolism, and apoptosis. Moreover, a wide range of information produced via several investigations indicates their tumor-suppressing, oncogenic, diagnostic assessment, and predictive marker functions in different types of lung malignancy. miRNA mimics or anti-miRNAs can be transferred into a lung cancer cell, with possible curative implications. As a result, miRNAs hold promise as targets for lung cancer treatment and detection. In this study, we investigate the different functions of various miRNAs in different types of lung malignancy, which have been achieved in recent years that show the lung cancer-associated regulation of miRNAs expression, concerning their function in lung cancer beginning, development, and resistance to chemotherapy, also the probability to utilize miRNAs as predictive biomarkers for therapy reaction.

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.

CHI3L1 induces autophagy through the JNK pathway in lung cancer cells

CHI3L1 is closely related to the molecular mechanisms of cancer cell migration, growth, and death. According to recent research, autophagy regulates tumor growth during various stages of cancer development. This study examined the association between CHI3L1 and autophagy in human lung cancer cells. In CHI3L1-overexpressing lung cancer cells, the expression of LC3, an autophagosome marker, and the accumulation of LC3 puncta increased. In contrast, CHI3L1 depletion in lung cancer cells decreased the formation of autophagosomes. Additionally, CHI3L1 overexpression promoted the formation of autophagosomes in various cancer cell lines: it also increased the co-localization of LC3 and the lysosome marker protein LAMP-1, indicating an increase in the production of autolysosomes. In mechanism study, CHI3L1 promotes autophagy via activation of JNK signaling. JNK may be crucial for CHI3L1-induced autophagy since pretreatment with the JNK inhibitor reduced the autophagic effect. Consistent with the in vitro model, the expression of autophagy-related proteins was downregulated in the tumor tissues of CHI3L1-knockout mice. Furthermore, the expression of autophagy-related proteins and CHI3L1 increased in lung cancer tissues compared with normal lung tissues. These findings show that CHI3L1-induced autophagy is triggered by JNK signals and that CHI3L1-induced autophagy could be a novel therapeutic approach to lung cancer.

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.

[The role of miRNA in the pathogenesis of diseases associated with functional dysregulation of the lacrimal gland]

At this time, the mechanism causing lacrimal gland dysfunction is not understood completely. In diseases associated with lacrimal gland involvement (Sjogren's syndrome, sarcoidosis, IgG4-associated disease, etc.) patients have been observed to experience elevated cellular apoptosis, active production of autoantibodies to glandular tissue, increased level of pro-inflammatory cytokines, functional disruption of signaling molecules leading to changes in tear production. Difficulties in differential diagnosis of lacrimal gland dysfunction in above-listed diseases are associated, on the one hand, with similarity of the clinical picture of ophthalmological manifestations, and on the other hand - with complicated morphological interpretation of changes in the glandular tissues. In this view, miRNA is a promising diagnostic and prognostic marker that would help with differential diagnosis as well as with choosing the treatment tactics. Methods of molecular profiling and identification of "molecular phenotypes" of lacrimal gland and ocular surface damage will allow the use of miRNA as biomarkers and prognostic factors for personalized treatment.

A Natural CHI3L1-Targeting Compound, Ebractenoid F, Inhibits Lung Cancer Cell Growth and Migration and Induces Apoptosis by Blocking CHI3L1/AKT Signals

Our previous big data analyses reported a strong association between CHI3L1 expression and lung tumor development. In this present study, we investigated whether a CHI3L1-inhibiting natural compound, ebractenoid F, inhibits lung cancer cell growth and migration and induces apoptosis. Ebractenoid F concentration-dependently (0, 17, 35, 70 µM) and significantly inhibited the proliferation and migration of A549 and H460 lung cancer cells and induced apoptosis. In the mechanism study, we found that ebractenoid F bound to CHI3L1 and suppressed CHI3L1-associated AKT signaling. Combined treatment with an AKT inhibitor, LY294002, and ebractenoid F synergistically decreased the expression of CHI3L1. Moreover, the combination treatment further inhibited the growth and migration of lung cancer cells and further induced apoptosis, as well as the expression levels of apoptosis-related proteins. Thus, our data demonstrate that ebractenoid F may serve as a potential anti-lung cancer compound targeting CHI3L1-associated AKT signaling.

Effects of USF1 SNPs and SNP–Environment Interactions on Serum Lipid Profiles and the Risk of Early-Onset Coronary Artery Disease in the Chinese Population

Background

Upstream transcription factor 1 (USF1) single-nucleotide polymorphisms (SNPs) are significantly associated with serum lipid levels in several different ethnic groups or populations, but their association with lipid levels and the risk of early-onset coronary artery disease (EOCAD) has not been reported in Han populations of southern China.

Methods

Six USF1 SNPs (rs3737787, rs2774276, rs2516839, rs2516838, rs1556259, and rs2516837) were genotyped by next-generation sequencing (NGS) techniques in 686 control subjects and 728 patients with EOCAD.

Results

The genotypic and allelic frequencies of the USF1 rs3737787 SNP were significantly different between the control and EOCAD groups. The subgroup analysis identified that the rs3737787T allele was related to a decreased risk of EOCAD, whereas the rs3737787C–rs2774276G–rs2516839A and rs3737787C–rs2774276G–rs2516839G haplotypes were related to an increased risk of EOCAD in men, and the rs3737787C–rs2774276G–rs2516839A and rs3737787T–rs2774276C–rs2516839A haplotypes were correlated with an increased risk of EOCAD in women (p < 0.05–0.01). Male rs3737787T allele carriers had lower low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), and triglyceride (TG) concentrations than the rs3737787T allele non-carriers (p < 0.01). The interactions of rs3737787 with alcohol consumption and rs2516839 with smoking affected serum TC and LDL-C levels in men, whereas the interaction of rs3737787 with alcohol consumption affected serum high-density lipoprotein cholesterol (HDL-C) levels and the rs2516839-smoking interaction affected serum TC levels in women (pI < 0.001). The expression levels of the USF1 mRNA, interleukin 1β (IL-1β), tumor necrosis factor-α (TNF-α), and interleukin 6 (IL-6) were significantly lower in controls than in patients with EOCAD, and rs3737787T allele carriers displayed lower IL-1β, TNF-α, IL-6, and USF1 mRNA expression levels than the rs3737787T allele non-carriers. In addition, IL-1β, TNF-α, and IL-6 expression levels were significantly positively correlated with USF1 mRNA levels (p < 0.01).

Conclusion

Sex-specific correlations were identified between the USF1 rs3737787T allele with blood lipid levels and the risk of EOCAD. The USF1 rs3737787T allele affects the risk of EOCAD by modulating serum lipid levels and the expression of inflammatory factors, including IL-1β, TNF-α, and IL-6.

SEZ6L2, regulated by USF1, accelerates the growth and metastasis of breast cancer

Breast cancer (BC) is the second cause of cancer-related mortality in women. Seizure related 6 homolog like 2 (SEZ6L2), a protein presented on cell surface, is involved in tumor development. It was found to be highly expressed in BC, however, its role in BC remains unclear. Herein, we aimed to explore the role of SEZ6L2 in BC. Firstly, the correlationship between SEZ6L2 expression and the clinic pathological characteristics of patients diagnosed with BC was analyzed. Subsequently, the role of SEZ6L2 was further explored using MTT, transwell invasion, flow cytometry, colony formation and wound healing assays. The result showed that the level of SEZ6L2 was remarkably correlated with the TNM stage, HER-2 status and lymph node metastasis of BC. Knockdown of SEZ6L2 significantly suppressed the proliferation of BC cells and induced cell cycle arrest at G1 phase. In addition, SEZ6L2 knockdown repressed their migration and invasion. On the contrary, SEZ6L2 overexpression performed the opposite effects. Furthermore, SEZ6L2 also accelerated the in vivo tumorigenesis of BC cells. Additionally, according to bioinformatics resources, we identified upstream transcription factor 1 (USF1) as a transcriptional factor which bound to the promoter of SEZ6L2 and positively regulated its transcription. In conclusion, this study demonstrated that SEZ6L2 was transcriptionally regulated by USF1 and was involved in the growth and metastasis of BC cells. Revealing the role of SEZ6L2 in BC provides additional knowledge for the pathogenesis of BC, which may benefit to BC therapy.

System analysis of FHIT in LUAD and LUSC: The expression, prognosis, gene regulation network, and regulation targets

BACKGROUND

Fragile histidine triad (FHIT) is a strong tumor suppressor gene, and cells deficient in FHIT are prone to acquiring cancer-promoting mutations. Due to its location, deletions within FHIT are common in cancer. Over 50% of cancers show loss of FHIT expression. However, to date, expression levels, gene regulatory networks, prognostic value, and target prediction of FHIT in lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) have not been fully reported. Therefore, systematic analysis of FHIT expression, gene regulatory network, prognostic value, and targeted prediction in patients with LUAD and LUSC has important guiding significance, providing new therapeutic targets and strategies for clinical treatment of lung cancer to further improve the therapeutic effect of lung cancer.

METHODS

Multiple free online databases were used for the abovementioned analysis in this study, including cBioPortal, TRRUST, Human Protein Atlas, GeneMANIA, GEPIA, Metascape, UALCAN, LinkedOmics, and TIMER.

RESULTS

FHIT was upregulated in patients with LUAD, and downregulated in patients with LUSC. Genetic alterations of FHIT were found in patients with LUAD (7%), and LUSC (10%). The promoter methylation of FHIT was lower in patients with LUAD and LUSC. FHIT expression significantly correlated with LUSC pathological stages. Furthermore, patients with LUAD and LUSC having low FHIT expression levels had a longer survival than those having high FHIT expression levels. FHIT and its neighboring genes (the 50 most frequently altered neighboring genes of FHIT) functioned in the regulation of protein kinase and DNA binding in patients with LUAD, as well as cell channels and membrane potential in patients with LUSC. Gene ontology enrichment analysis revealed that the functions of FHIT and its neighboring genes are mainly related to disordered domain-specific binding, protein kinase binding, and ion gated channel activity in patients with LUAD, as well as calcium ion binding and intracellular ligand-gated ion channel activity in patients with LUSC. Transcription factor targets of FHIT and its neighboring genes in patients with lung cancer were found: USF1, SOX6, USF2, SIRT1, VHL, LEF1, EZH2, TP53, HDAC1, ESR1, EGR1, YY1, MYC, RELA, NFKB1, and E2F1 in LUAD; and HDAC1, DNMT1, and E2F1 in LUSC. We further explored the FHIT-associated kinase (PRKCQ, AURKB and ATM in LUAD as well as PLK3 in LUSC) and FHIT-associated miRNA targets (MIR-188, MIR-323, and MIR-518A-2 in LUAD). Furthermore, the following genes had the strongest correlation with FHIT expression in patients with lung cancer: NICN1, HEMK1, and BDH2 in LUAD, and ZMAT1, TTC21A, and NICN1 in LUSC. FHIT expression was positively associated with immune cell infiltration (B cell) in patients with LUAD, as well as B cell, CD8 + T, CD4 + T cells, macrophages, and dendritic cells in patients with LUSC. Nevertheless, FHIT expression was negatively associated with CD8 + T cells and neutrophils in patients with LUAD.

CONCLUSIONS

The expression, gene regulatory network, prognostic value and targeted prediction of FHIT in patients with LUAD and LUSC were systematically analyzed and revealed in this study, thereby laying a foundation for further research on the role of FHIT in LUAD and LUSC occurrence. This study provides new LUAD and LUSC therapeutic targets and prognostic biomarkers as a reference for fundamental and clinical research.

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.

Anti-Chi3L1 antibody suppresses lung tumor growth and metastasis through inhibition of M2 polarization

Chitinase 3-like 1 (Chi3L1) is associated with various biological processes, such as inflammation, tissue repair, proliferation, cell survival, invasion, and extracellular matrix remodeling. Recent studies indicated that Chi3L1 is critical for cancer development and metastasis. In this study, we demonstrate that Chi3L1 serum and tissue levels were significantly increased in lung cancer patients compared with controls. We previously developed an anti-Chi3L1-humanized antibody, and here, we investigate its antitumor and antimetastatic effect. The anti-Chi3L1 antibody attenuated tumor growth and metastasis both in vitro and in vivo in a lung cancer mouse model. These inhibitory effects are associated with signal transducer and activator of transcription 6 (STAT6)-dependent M2 polarization inhibition. Proteomics analysis revealed that plasminogen (PLG) interacts with Chi3L1 and affects M2 polarization. Chi3L1 plays a critical role in lung cancer progression, and the anti-Chi3L1 antibody could be a new anticancer therapy.

TUG1 long non-coding RNA enlists the USF1 transcription factor to overexpress ROMO1 leading to hepatocellular carcinoma growth and metastasis

Hepatocellular carcinoma (HCC) is a prevalent and highly aggressive cancer. Long non‐coding RNAs (lncRNAs) are recognized as potential molecular targets for HCC and are currently under increased research focus. Here, we investigate the regulatory processes underlying the axis of the lncRNA taurine upregulated gene 1 (TUG1), Upstream Transcription Factor 1 (USF1), and reactive oxygen species modulator 1 (ROMO1) in the propagation and metastasis of HCC cells. Distribution of lncRNA TUG1 was found to be prominent in HCC cell cytoplasm and nuclei. LncRNA TUG1 conscripted the USF1 transcription factor to enhance the promoter function of ROMO1. Enlisting the USF1 transcription factor to increase ROMO1 expression following upregulation of TUG1 lncRNA enhanced HCC Huh7 cell proliferation, motility, and metastasis. Rapid tumor proliferation in nude mice provided in vivo verification. The importance of the lncRNA TUG1/USF1/ROMO1 complex as a target for HCC therapy is a key result of this investigation which is exemplified by its role in regulating the proliferation, motility, and metastasis of HCC cells.

A small molecule targeting CHI3L1 inhibits lung metastasis by blocking IL-13Rα2-mediated JNK-AP-1 signals

Our previous big data analyses showed a high level of association between chitinase 3 like1 (CHI3L1) expression and lung tumor development. In the present study, we investigated whether a CHI3L1‐inhibiting chemical, 2‐({3‐[2‐(1‐cyclohexen‐1‐yl)ethyl]‐6,7‐dimethoxy‐4‐oxo‐3,4‐dihydro‐2‐quinazolinyl}sulfanyl)‐N‐(4‐ethylphenyl)butanamide (K284), could inhibit lung metastasis and studied its mechanism of action. We investigated the antitumor effect of K284 both in vitro and in vivo. K284 (0.5 mg·kg⁻¹ body weight) significantly inhibited lung metastasis in in vivo models after injection of murine melanoma cells (B16F10) or adenocarcinomic human alveolar basal epithelial cells (A549). K284 significantly and concentration‐dependently also inhibited cancer cell proliferation and migration in the A549 and H460 lung cancer cell lines. We found that the binding of K284 to the chitin‐binding domain (CBD) of CHI3L1 prevented the binding of CHI3L1 to its receptor, interleukin‐13 receptor subunit alpha‐2 (IL‐13Rα2), thereby suppressing the CHI3L1 signal. This blocking of the CHI3L1‐IL‐13Rα2 signal caused the inhibition of c‐Jun N‐terminal kinase (JNK)‐activator protein 1 (AP‐1) signals, resulting in the prevention of lung metastasis and cancer cell growth. Our data demonstrate that K284 may serve as a potential candidate anticancer compound targeting CHI3L1.

Association of Exosomal miR-210 with Signaling Pathways Implicated in Lung Cancer

MicroRNA is a class of non-coding RNA involved in post-transcriptional gene regulation. Aberrant expression of miRNAs is well-documented in molecular cancer biology. Extensive research has shown that miR-210 is implicated in the progression of multiple cancers including that of the lung, bladder, colon, and renal cell carcinoma. In recent years, exosomes have been evidenced to facilitate cell–cell communication and signaling through packaging and transporting active biomolecules such as miRNAs and thereby modify the cellular microenvironment favorable for lung cancers. MiRNAs encapsulated inside the lipid bilayer of exosomes are stabilized and transmitted to target cells to exert alterations in the epigenetic landscape. The currently available literature indicates that exosomal miR-210 is involved in the regulation of various lung cancer-related signaling molecules and pathways, including STAT3, TIMP-1, KRAS/BACH2/GATA-3/RIP3, and PI3K/AKT. Here, we highlight major findings and progress on the roles of exosomal miR-210 in lung cancer.

miR-210-3p Promotes Lung Cancer Development and Progression by Modulating USF1 and PCGF3

Purpose

Lung cancer represents one of the most frequent solid tumors. Adenocarcinoma is a common type of tumor and a significant threat to individual health globally. MicroRNAs (miRNAs) are recognized as critical governors of gene expression during carcinogenesis, while their effects on lung cancer occurrence and development are required for further investigation. Herein, the functional role of miR-210-3p and its regulation mechanism were characterized in lung cancer.

Methods

A total of 50 pairs of tumor and tumor-free lung tissues were surgically resected from lung cancer patients. Dual-luciferase reporter assay and RNA immunoprecipitation assay were performed to examine USF1 binding with miR-210-3p and PCGF3. Cultured human lung cancer cells A549 were assayed for viability, apoptosis, migration, and invasion in vitro by CCK-8 test, flow cytometry, transwell chamber assays, tumorigenesis, and lymph node metastasis in vivo by mouse xenograft experiments.

Results

miR-210-3p was upregulated in lung cancer tissues. The inhibition of miR-210-3p by specific inhibitor tempered lung cancer development and metastasis in vitro and in vivo. miR-210-3p targeted USF1 and inhibited its expression. USF1 was bound with PCGF3, which increased its transcription. PCGF3-specific knockdown mimicked the effect of miR-210-3p on lung cancer development and metastasis in vitro and in vivo.

Conclusion

The current study demonstrated that miR-210-3p facilitates lung cancer development and metastasis by impairing USF1-mediated promotion of PCGF3, which provides a better understanding of the mechanism of lung cancer development and metastasis.

Serum protein levels of YKL-40 and plasma miR-214 expression in patients with systemic sclerosis

OBJECTIVES

Systemic sclerosis (SSc) is an autoimmune disease with incompletely revealed etiology and pathophysiology. There are still no specific and reliable biomarkers. Here we examined YKL-40 as a biomarker of inflammation and fibrosis, and suggest a possible mechanism for its regulation.

METHODS

Forty female patients with SSc (26 with diffuse cutaneous (dcSSc) and 14 with limited cutaneous SSc (lcSSc)) and 14 healthy female controls were enrolled in this cross-sectional study. Bioinformatic tools identified miR-214 binding site in the 3'-untranslated region (3'UTR) of YKL-40 mRNA. Serum levels of YKL-40 were examined by ELISA, while YKL-40 mRNA and miR-214 was measured by qPCR.

RESULTS

The in silico analysis revealed several microRNAs (miRNAs) targeting YKL-40 mRNA, from which miR-214 was selected. YKL-40 serum levels were significantly higher in patients compared to controls (p = .0042). In contrary, miR-214 expression in plasma of SSc patients was significantly down-regulated compared to controls (p = .0058). Receiver operating characteristic (ROC) and area under the curve (AUC) analysis showed that both serum YKL-40 and plasma miR-214 levels had good capacity to distinguish patients with SSc, dcSSc and lcSSc from healthy subjects.

CONCLUSION

YKL-40 and miR-214 have different expression profile in SSc. Increased serum levels of YKL-40 could be associated with down-regulation of miR-214 expression in plasma. Both, YKL-40 concentrations and miR-214 plasma fold change values might serve as possible biomarkers in SSc.

K284-6111 alleviates memory impairment and neuroinflammation in Tg2576 mice by inhibition of Chitinase-3-like 1 regulating ERK-dependent PTX3 pathway

Background

Alzheimer’s disease (AD) is one of the most prevalent neurodegenerative disorders characterized by gradual memory loss and neuropsychiatric symptoms. We have previously demonstrated that the 2-({3-[2-(1-cyclohexene-1-yl)ethyl]-6,7-dimethoxy-4-oxo-3,4-dihydro-2-quinazolinyl}sulfanyl)-N-(4-ethylphenyl)butanamide (K284-6111), the inhibitor of CHI3L1, has the inhibitory effect on memory impairment in Αβ infusion mouse model and on LPS-induced neuroinflammation in the murine BV-2 microglia and primary cultured astrocyte.

Methods

In the present study, we investigated the inhibitory effect of K284-6111 on memory dysfunction and neuroinflammation in Tg2576 transgenic mice, and a more detailed correlation of CHI3L1 and AD. To investigate the effects of K284-6111 on memory dysfunction, we administered K284-6111 (3 mg/kg, p.o.) daily for 4 weeks to Tg2576 mice, followed by behavioral tests of water maze test, probe test, and passive avoidance test.

Results

Administration of K284-6111 alleviated memory impairment in Tg2576 mice and had the effect of reducing the accumulation of Aβ and neuroinflammatory responses in the mouse brain. K284-6111 treatment also selectively inactivated ERK and NF-κB pathways, which were activated when CHI3L1 was overexpressed, in the mouse brain and in BV-2 cells. Web-based gene network analysis and our results of gene expression level in BV-2 cells showed that CHI3L1 is closely correlated with PTX3. Our result revealed that knockdown of PTX3 has an inhibitory effect on the production of inflammatory proteins and cytokines, and on the phosphorylation of ERK and IκBα.

Conclusion

These results suggest that K284-6111 could improve memory dysfunction by alleviating neuroinflammation through inhibiting CHI3L1 enhancing ERK-dependent PTX3 pathway.

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.

Selection and Characterization of YKL-40-Targeting Monoclonal Antibodies from Human Synthetic Fab Phage Display Libraries

YKL-40, also known as chitinase-3-like 1 (CHI3L1), is a glycoprotein that is expressed and secreted by various cell types, including cancers and macrophages. Due to its implications for and upregulation in a variety of diseases, including inflammatory conditions, fibrotic disorders, and tumor growth, YKL-40 has been considered as a significant therapeutic biomarker. Here, we used a phage display to develop novel monoclonal antibodies (mAbs) targeting human YKL-40 (hYKL-40). Human synthetic antibody phage display libraries were panned against a recombinant hYKL-40 protein, yielding seven unique Fabs (Antigen-binding fragment), of which two Fabs (H1 and H2) were non-aggregating and thermally stable (75.5 °C and 76.5 °C, respectively) and had high apparent affinities (K_D = 2.3 nM and 4.0 nM, respectively). Reformatting the Fabs into IgGs (Immunoglobulin Gs) increased their apparent affinities (notably, for H1 and H2, K_D = 0.5 nM and 0.3 nM, respectively), presumably due to the effects of avidity, with little change to their non-aggregation property. The six anti-hYKL-40 IgGs were analyzed using a trans-well migration assay in vitro, revealing that three clones (H1, H2, and H4) were notably effective in reducing cell migration from both A549 and H460 lung cancer cell lines. The three clones were further analyzed in an in vivo animal test that assessed their anti-cancer activities, demonstrating that the tumor area and the number of tumor nodules were significantly reduced in the lung tissues treated with H1 (IgG). Given its high affinity and desirable properties, we expect that the H1 anti-hYKL-40 mAb will be a suitable candidate for developing anti-cancer therapeutics.

CHI3L1 in the pathophysiology and diagnosis of liver diseases

Chitinase 3-like protein 1(CHI3L1) participates in physiological and pathophysiological process, such as cell survival, cell proliferation, tissue remodeling, angiogenesis, etc. Some studies demonstrated that CHI3L1 is liver-enriched and has better application value in staging liver fibrosis than platelet ratio index(APRI) and fibrosis-4 index(FIB-4) and that CHI3L1 can be used in monitoring the prognosis of hepatocellular carcinoma (HCC). In this review, we summarized the pathophysiological role and the diagnostic value of CHI3L1 in liver fibrosis in different background and HCC.

Pak2 inhibition promotes resveratrol-mediated glioblastoma A172 cell apoptosis via modulating the AMPK-YAP signaling pathway

As a polyphenolic compound, resveratrol (Res) is widely present in a variety of plants. Previous studies have shown that Res can inhibit various tumors. However, its role in c remains largely unexplored. In the present study, we first demonstrated that Res inhibited cell viability and induced apoptosis of glioblastoma A172 cell. Further experiments showed that Res induced mitochondrial dysfunction and activated the activity of caspase-9. Functional studies have found that Res treatment is associated with an increase in the expression of Pak2. Interestingly, inhibition of Pak2 could further augment the proapoptotic effect of Res. Mechanistically, Pak2 inhibition induced reactive oxygen species overproduction, mitochondria-JNK pathway activation, and AMPK-YAP axis suppression. However, overexpression of YAP could abolish the anticancer effects of Res and Pak2 inhibition, suggesting a necessary role played by the AMPK-YAP pathway in regulating cancer-suppressive actions of Res and Pak2 inhibition. Altogether, our results indicated that Res in combination with Pak2 inhibition could further enhance the anticancer property of Res and this effect is mediated via the AMPK-YAP pathway.

Deletion of Chitinase-3-like 1 accelerates stroke development through enhancement of Neuroinflammation by STAT6-dependent M2 microglial inactivation in Chitinase-3-like 1 knockout mice

Chitinase 3-like 1 (Chi3L1) plays a major role in the pathogenesis of inflammatory diseases. We investigated the effect of Chi3L1 knockout on stroke development. Ischemia/reperfusion was induced by middle cerebral artery occlusion (MCAO) in Chi3L1 knockout and wildtype mice. Significantly increased infarct volume and decreased neurological deficit scores at 24 h after ischemia/reperfusion were found in Chi3L1 knockout mice compared to wildtype mice. Moreover, ischemic neuronal cell death was increased in Chi3L1 knockout mice through increased oxidative stress and release of IL-6 and IL-1β but IL-10 and IL-4 were reduced. Furthermore, expression of inflammation-related proteins (iNOS, COX-2, Iba-1, and GFAP) was significantly increased in Chi3L1 knockout mice compared to wildtype. In microglia isolated from MCAO-injured Chi3L1 knockout mice, expression of M1 markers (iNOS, CD86, IL-1β, and IL-6) was increased and M2 markers (Arg1, Mrc1, IL-10, and IL-4Ra) was decreased. In BV-2 cells, knockdown of Chi3L1 increased TNF-α- and INF-γ-induced expression of iNOS, COX-2, and Iba-1, but decreased the expression of Arg1, MRC1, and IL-4 receptor-alpha (IL-4Rα). Expression of IL-4Rα, an important factor of M2 polarization, and its downstream signals p-JAK1, p-JAK3, and p-STAT6, was much reduced in the knockout mice. Additionally, in BV-2 cells, knockdown of Chi3L1 by siRNA Chi3L1 decreased rhTNF-α- and INF-γ-induced expression of IL-4Rα, p-JAK1, p-JAK3, and p-STAT6. Furthermore, treatment with AS1517499 abolished Chi3L1 knockdown-induced reduced IL-4Rα and Arg1 but not CD86 expression. Our results indicate that deletion of Chi3L1 accelerates stroke development through enhancement of neuroinflammation by markedly decreasing STAT6-dependent M2 macrophage polarization.

Measured and genetically predicted plasma YKL-40 levels and melanoma mortality

PURPOSE

High plasma levels of YKL-40 might be associated with mortality in patients with melanoma, and it is unknown if YKL-40 is causally related to mortality.

EXPERIMENTAL DESIGN

We studied two cohorts: 2618 patients with melanoma from hospital clinics and 1413 general population patients with melanoma, totalling 4031 patients followed up for mortality end-points for up to 20 years. All were genotyped for CHI3L1 rs4950928, highly predictive of lifelong plasma YKL-40, and plasma YKL-40 levels were measured in 2165 patients. We tested the hypotheses that measured and genetically predicted high plasma YKL-40 are associated with increased mortality in patients with melanoma.

RESULTS

For the hospital melanoma cohort, age- and sex-adjusted hazard ratios for death in individuals with measured plasma YKL-40 in the 96-100th percentile versus 1-95th percentile and per 10-percentile increase were 1.52 (95% confidence interval, 1.07-2.16) and 1.07 (1.02-1.11), respectively, most pronounced for patients with localised melanomas. Each C-allele of the CHI3L1 rs4950928 genotype was associated with plasma YKL-40 level increases of 32% in the hospital melanoma cohort (p = 6 × 10^-48) and 43% in the general population melanoma cohort (p = 7 × 10^-13). Multifactorially adjusted ratios for these increases in the combined cohorts were 1.04 (1.00-1.09) observationally for measured plasma YKL-40 and 0.98 (0.86-1.12) for the genetically predicted plasma YKL-40.

CONCLUSION

Measured, but not genetically predicted, increasing plasma YKL-40 was associated with increased mortality in patients with melanoma. Plasma YKL-40 is a marker but less likely to be a cause of increased mortality in patients with melanoma.

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

Chitinase 3-like 1 (CHI3L1) is a secreted glycoprotein that mediates inflammation, macrophage polarization, apoptosis, and carcinogenesis. The expression of CHI3L1 is strongly increased by various inflammatory and immunological conditions, including rheumatoid arthritis, multiple sclerosis, Alzheimer's disease, and several cancers. However, its physiological and pathophysiological roles in the development of cancer and neurodegenerative and inflammatory diseases remain unclear. Several studies have reported that CHI3L1 promotes cancer proliferation, inflammatory cytokine production, and microglial activation, and that multiple receptors, such as advanced glycation end product, syndecan-1/αVβ3, and IL-13Rα2, are involved. In addition, the pro-inflammatory action of CHI3L1 may be mediated via the protein kinase B and phosphoinositide-3 signaling pathways and responses to various pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin-1β, interleukin-6, and interferon-γ. Therefore, CHI3L1 could contribute to a vast array of inflammatory diseases. In this article, we review recent findings regarding the roles of CHI3L1 and suggest therapeutic approaches targeting CHI3L1 in the development of cancers, neurodegenerative diseases, and inflammatory diseases.

Chitinase-3-like-1 deficiency attenuates ethanol-induced liver injury by inhibition of sterol regulatory element binding protein 1-dependent triglyceride synthesis

OBJECTIVE

Alcohol overconsumption and abuse lead to alcoholic liver disease (ALD), which is a major chronic liver disease worldwide. Chitinase-3-like protein 1 (CHI3L1) have an important role in the pathogenesis of inflammatory disease. However, the role of CHI3L1 in ALD has not yet been reported. In the present study, we investigated the effect of CHI3L1 on chronic plus binge ethanol-induced liver injury.

METHODS

CHI3L1 knock out (KO) mice and their littermate control mice based on C57BL/6 (10-12 weeks old) were fed on a Lieber-DeCarli diet containing 6.6% ethanol for 10 days. And, CHI3L1 siRNA or CHI3L1 expressing vector was transfected HepG2 cells were treated with ethanol or without.

RESULTS

Ethanol-induced hepatic triglyceride (TG) levels and the mRNA levels of TG synthesis-related genes such as acetyl-CoA carboxylase (ACC), fatty acid synthase (FAS) and stearoyl-CoA desaturase-1 (SCD1) were decreased in the liver of CHI3L1 knock out (KO) mice and the HepG2 cells transfected with CHI3L1 siRNA. Increased mRNA level and activation of SREBP1 which is transcription factor of ACC, FAS and SCD1 by ethanol feeding were reduced in the liver of ethanol-fed CHI3L1 KO mice. Moreover, ethanol-induced SREBP1 luciferase activity and mRNA level of SREBP1, ACC, FAS and SCD1 were also decreased in the HepG2 cells transfected with CHI3L1 siRNA, while those were further increased in the HepG2 cells treated with recombinant human CHI3L1. Furthermore, oxidative stress and up-regulated pro-inflammatory cytokines by ethanol were recovered in the liver of ethanol-fed CHI3L1 KO mice.

CONCLUSION

Our finding suggest that inhibition of CHI3L1 suppressed ethanol-induced liver injury through inhibition of TG synthesis, and the blocking of oxidative stress and hepatic inflammation induced SREBP1 activity could be significant.

Human Chitinases: Structure, Function, and Inhibitor Discovery

Chitinases are glycosyl hydrolases that hydrolyze the β-(1-4)-linkage of N-acetyl-D-glucosamine units present in chitin polymers. Chitinases are widely distributed enzymes and are present in a wide range of organisms including insects, plants, bacteria, fungi, and mammals. These enzymes play key roles in immunity, nutrition, pathogenicity, and arthropod molting. Humans express two chitinases, chitotriosidase 1 (CHIT1) and acid mammalian chitinase (AMCase) along with several chitinase-like proteins (CLPs). Human chitinases are reported to play a protective role against chitin-containing pathogens through their capability to degrade chitin present in the cell wall of pathogens. Now, human chitinases are gaining attention as the key players in innate immune response. Although the exact mechanism of their role in immune response is not known, studies in recent years begin to relate chitin recognition and degradation with the activation of signaling pathways involved in inflammation. The roles of both CHIT1 and AMCase in the development of various diseases have been revealed and several classes of inhibitors have been developed. However, a clear understanding could not be established due to complexities in the design of the right experiment for studying the role of human chitinase in various diseases. In this chapter, we will first outline the structural features of CHIT1 and AMcase. We will then review the progress in understanding the role of human chitinases in the development of various diseases. Finally, we will summarize the inhibitor discovery efforts targeting both CHIT1 and AMCase.