Elevated YKL40 is associated with advanced prostate cancer (PCa) and positively regulates invasion and migration of PCa cells

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

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

Upregulation of YKL-40 Promotes Metastatic Phenotype and Correlates with Poor Prognosis and Therapy Response in Patients with Colorectal Cancer

YKL-40 is a heparin- and chitin-binding glycoprotein that belongs to the family of glycosyl hydrolases but lacks enzymatic properties. It affects different (patho)physiological processes, including cancer. In different tumors, YKL-40 gene overexpression has been linked to higher cell proliferation, angiogenesis, and vasculogenic mimicry, migration, and invasion. Because, in colorectal cancer (CRC), the serological YKL-40 level may serve as a risk predictor and prognostic biomarker, we investigated the underlying mechanisms by which it may contribute to tumor progression and the clinical significance of its tissue expression in metastatic CRC. We demonstrated that high-YKL-40-expressing HCT116 and Caco2 cells showed increased motility, invasion, and proliferation. YKL-40 upregulation was associated with EMT signaling activation. In the AOM/DSS mouse model, as well as in tumors and sera from CRC patients, elevated YKL-40 levels correlated with high-grade tumors. In retrospective analyses of six independent cohorts of CRC patients, elevated YKL-40 expression correlated with shorter survival in patients with advanced CRC. Strikingly, high YKL-40 tissue levels showed a predictive value for a better response to cetuximab, even in patients with stage IV CRC and mutant KRAS, and worse sensitivity to oxaliplatin. Taken together, our findings establish that tissue YKL-40 overexpression enhances CRC metastatic potential, highlighting this gene as a novel prognostic candidate, a predictive biomarker for therapy response, and an attractive target for future therapy in CRC.

Prognostic value of YKL-40 in colorectal carcinoma patients: A meta-analysis

BACKGROUND

In recent years, the predictive role of YKL-40 for long-term survival in colorectal cancer patients has been gradually investigated. However, whether it is a reliable and valuable prognostic indicator for patients with colorectal carcinoma has not been verified.

AIM

To identify the prognostic value of serum/plasma concentration of YKL-40 or expression status of YKL-40 in tumor cells in colorectal carcinoma patients.

METHODS

Several electronic databases including the PubMed, EMBASE, Web of Science, CNKI, VIP and WanFang were searched for relevant studies. The hazard ratios (HR) and 95% confidence intervals (CI) were combined and the primary and secondary outcomes were overall survival (OS) and progression-free survival (PFS), respectively. All statistical analysis were conducted by STATA 15.0 software.

RESULTS

A total of nine studies involving 2545 patients were included. The pooled results indicated that YKL-40 was significantly associated with poor OS (HR = 1.80, 95%CI: 1.32-2.45, P < 0.001) and PFS (HR = 1.62, 95%CI: 1.22-2.16, P = 0.001). Subgroup analysis stratified by the treatment, tumor type and source of YKL-40 showed similar results.

CONCLUSION

Elevated serum/plasma concentration of YKL-40 or positive expression in tumor cells was related with worse prognosis of colorectal carcinoma patients. YKL-40 might serve as a novel and reliable indicator for the evaluation of prognosis in colorectal cancer.

Diagnostic and prognostic value of serum Chitinase 3-like protein 1 in hepatocellular carcinoma

The serum Chitinase 3‐like protein 1 (CHI3L1) protein level can distinguish the stages of liver fibrosis to a great extent. However, the diagnostic and prognostic significance of serum CHI3L1 in hepatocellular carcinoma (HCC) is not clarified. To evaluate the diagnostic and prognostic value of CHI3L1 in HCC, a total of 128 HCC patients treated in the HwaMei Hospital, University of Chinese Academy of Sciences, from December 2018 to April 2020 were collected retrospectively. Matched age and gender subjects, 40 patients with liver cirrhosis, 40 patients with chronic hepatitis, and 40 healthy subjects were enrolled in the control group. The relevant clinical laboratory and examination data and the overall survival time (OS) of the HCC patients were collected. The serum CHI3L1 expression level is related to α‐fetoprotein (AFP), tumor‐node‐metastasis (TNM) stage, maximum tumor diameter, liver cirrhosis, and HCC patient's OS (p < 0.05). The area under the curve (AUC) of CHI3L1 was 0.7875 with the cutoff value of 91.36 ng/ml. Combining the serum CHI3L1 and α‐fetoprotein (AFP) by a binary logistic regression model can increase the diagnostic sensitivity to 97.5%. Multivariate Cox regression analysis indicated that CHI3L1 is an independent prognostic factor in patients with HCC.

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.

Macrophage Biology and Mechanisms of Immune Suppression in Breast Cancer

Macrophages are crucial innate immune cells that maintain tissue homeostasis and defend against pathogens; however, their infiltration into tumors has been associated with adverse outcomes. Tumor-associated macrophages (TAMs) represent a significant component of the inflammatory infiltrate in breast tumors, and extensive infiltration of TAMs has been linked to poor prognosis in breast cancer. Here, we detail how TAMs impede a productive tumor immunity cycle by limiting antigen presentation and reducing activation of cytotoxic T lymphocytes (CTLs) while simultaneously supporting tumor cell survival, angiogenesis, and metastasis. There is an urgent need to overcome TAM-mediated immune suppression for durable anti-tumor immunity in breast cancer. To date, failure to fully characterize TAM biology and classify multiple subsets has hindered advancement in therapeutic targeting. In this regard, the complexity of TAMs has recently taken center stage owing to their subset diversity and tightly regulated molecular and metabolic phenotypes. In this review, we reveal major gaps in our knowledge of the functional and phenotypic characterization of TAM subsets associated with breast cancer, before and after treatment. Future work to characterize TAM subsets, location, and crosstalk with neighboring cells will be critical to counteract TAM pro-tumor functions and to identify novel TAM-modulating strategies and combinations that are likely to enhance current therapies and overcome chemo- and immuno-therapy resistance.

Steroid Hormone Receptor and Infiltrating Immune Cell Status Reveals Therapeutic Vulnerabilities of ESR1-Mutant Breast Cancer

Mutations in ESR1 that confer constitutive estrogen receptor alpha (ER) activity in the absence of ligand are acquired by ≥40% of metastatic breast cancers (MBC) resistant to adjuvant aromatase inhibitor (AI) therapy. To identify targetable vulnerabilities in MBC, we examined steroid hormone receptors and tumor-infiltrating immune cells in metastatic lesions with or without ER mutations. ER and progesterone receptor (PR) were significantly lower in metastases with wild-type (WT) ER compared with those with mutant ER, suggesting that metastases that evade AI therapy by mechanism(s) other than acquiring ER mutations lose dependency on ER and PR. Metastases with mutant ER had significantly higher T regulatory and Th cells, total macrophages, and programmed death ligand-1 (PD-L1)-positive immune-suppressive macrophages than those with WT ER. Breast cancer cells with CRISPR-Cas9-edited ER (D538G, Y537S, or WT) and patient-derived xenografts harboring mutant or WT ER revealed genes and proteins elevated in mutant ER cells, including androgen receptor (AR), chitinase-3-like protein 1 (CHI3L1), and IFN-stimulated genes (ISG). Targeting these proteins blunted the selective advantage of ER-mutant tumor cells to survive estrogen deprivation, anchorage independence, and invasion. Thus, patients with mutant ER MBC might respond to standard-of-care fulvestrant or other selective ER degraders when combined with AR or CHI3L1 inhibition, perhaps with the addition of immunotherapy. SIGNIFICANCE: Targetable alterations in MBC, including AR, CHI3L1, and ISG, arise following estrogen-deprivation, and ER-mutant metastases may respond to immunotherapies due to elevated PD-L1⁺ macrophages.See related article by Arnesen et al., p. 539.

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.

A robust strategy for proteomic identification of biomarkers of invasive phenotype complexed with extracellular heat shock proteins

As an extension of their orchestration of intracellular pathways, secretion of extracellular heat shock proteins (HSPs) is an emerging paradigm of homeostasis imperative to multicellular organization. Extracellular HSP is axiomatic to the survival of cells during tumorigenesis; proportional representation of specific HSP family members is indicative of invasive potential and prognosis. Further significance has been added by the knowledge that all cancer-derived exosomes have surface-exposed HSPs that reflect the membrane topology of cells that secrete them. Extracellular HSPs are also characteristic of chronic inflammation and sepsis. Accordingly, interrogation of extracellular HSPs secreted from cell culture models may represent a facile means of identifying translational biomarker signatures for targeting in situ. In the current study, we evaluated a simple peptide-based multivalent HSP affinity approach using the Vn96 peptide for low speed pelleting of HSP complexes from bioreactor cultures of cell lines with varying invasive phenotype in xenotransplant models: U87 (glioblastoma multiforme; invasive); HELA (choriocarcinoma; minimally invasive); HEK293T (virally transformed immortalized; embryonic). Proteomic profiling by bottom-up mass spectrometry revealed a comprehensive range of candidate biomarkers including primary HSP ligands. HSP complexes were associated with additional chaperones of prognostic significance such as protein disulfide isomerases, as well as pleiotropic metabolic enzymes, established as proportionally reflective of invasive phenotype. Biomarkers of inflammatory and mechanotransductive phenotype were restricted to the most invasive cell model U87, including chitinase CHI3L1, lamin C, amyloid derivatives, and histone isoforms.

Prognostic value of YKL-40 in solid tumors: a meta-analysis of 41 cohort studies

Background

Serum/plasma YKL-40 can be a useful index that is associated with tumor development. However, the prognostic value of serum/plasma YKL-40 in patients with solid tumors is still unclear. We aimed to utilize the existing literature to investigate the prognostic value of serum/plasma YKL-40 in solid tumors.

Methods

An extensive literature search for relevant studies was conducted with the Embase, Medline and Web of Science databases. The effect on survival was measured with the hazard ratio (HR). Then, pooled HRs and 95% confidence intervals (CIs) were calculated using the random and fixed-effects models according to the heterogeneity of the included studies.

Results

This meta-analysis was based on 41 publications and comprised a total of 7762 patients with solid tumors. The pooled HR showed that elevated serum/plasma YKL-40 was significantly associated with poor OS (HR, 1.44; 95% CI 1.33–1.56). We also found that elevated serum/plasma YKL-40 had significant prognostic effects on OS in various cancer subgroups such as gastrointestinal tumors (HR, 1.37; 95% CI 1.18–1.58), ovarian cancer (HR, 2.27; 95% CI 1.69–3.06), melanoma (HR, 1.77; 95% CI 1.18–2.67), lung cancer (HR, 1.73; 95% CI 1.35–2.23), urologic neoplasms (HR, 1.61; 95% CI 1.08–2.40) and glioblastoma (HR, 1.23; 95% CI 1.07–1.42); in contrast, the prognostic effect of serum/plasma YKL-40 was not statistically significant in breast cancer (HR, 1.07; 95% CI 0.98–1.17).

Conclusions

The available evidence supports the hypothesis that elevated serum/plasma YKL-40 is associated with poor survival in patients with solid tumors and that serum/plasma YKL-40 may serve as a novel prognostic biomarker.

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.

The Assessment of Clinical Usage and Prognostic Value of YKL-40 Serum Levels in Patients With Rectal Cancer Without Distant Metastasis

BACKGROUND

Colorectal cancer is one of the most common and significant malignancies in the world. YKL-40 (chitinase-3-like protein 1) is involved in cell proliferation, migration, inflammation, and tissue remodeling; and serum levels of YKL-40 are associated with patient outcome in various cancers. The aim of this study was to assess the potential clinical usage of YKL-40 pretreatment serum levels as a prognostic biomarker in rectal cancer.

METHODS

Concentrations of YKL-40 and standard tumor marker-Carcinoembryonic antigen (CEA)-were assessed in serum of 83 patients with rectal cancer without distant metastasis, and association with clinicopathological characteristics and disease-free and overall survival was evaluated.

RESULTS

Concentration of YKL-40 was significantly higher in serum of patients with rectal cancer compared to healthy controls ( P = .0001), and YKL-40 levels were able to predict rectal cancer (area under the Receiver Operating Characteristic [ROC] curve = .769) with higher accuracy than CEA (area under the ROC curve = .728) in patients with early stage disease. Increased YKL-40 levels were significantly associated with age ( P = .001); however, no association with other clinicopathological characteristics was observed. Finally, in patients with recurrence, the percentage of cases with increased concentration of YKL-40 was significantly higher than in patients without recurrence ( P = .041), and Kaplan-Meier analysis demonstrated that elevated YKL-40 concentration is a predictor of poor overall survival in patients with rectal cancer.

CONCLUSION

Pretreatment serum levels of YKL-40 may be a novel prognostic factor of overall and disease-free survival in patients with nonmetastatic colorectal cancer.

Circulating monocytes from prostate cancer patients promote invasion and motility of epithelial cells

BACKGROUND

Recruited myeloid cells are known to promote cancer initiation, malignant progression, metastasis, and resistance to therapy in the tumor niche. We tested the hypothesis that circulating blood monocytes from advanced prostate cancer (PCa) patients exhibit a protumor phenotype and directly influence the tumor microenvironment in response to tumor-derived signals.

METHODS

Blood monocytes from advanced and stable PCa patients were cultured, and the conditioned media (CM) were collected and analyzed using standard invasion and wound closure assays to measure effects on invasion and motility of PCa tumor cells. We then identified the proteome profile of these monocytes using proteome array and ELISA.

RESULTS

Conditioned media from circulating monocytes in patients with metastatic prostate cancer (PCa-M) increased invasion of epithelial PCa cells in vitro. Proteome Profiler Analysis revealed that monocyte-derived CM from metastatic castration-resistant (mCRPC) patients presented high levels of chitinase-3-like 1 (CHI3L1, YKL-40) when compared to patients with stable disease (PCa-N) and healthy control individuals (HC). The only described receptor for CHI3L1, interleukin-13 receptor α2 (IL-13Rα2), was significantly up-regulated in the human metastatic PCa cell line, ARCaPM . Accordingly, we observed that the activation of IL-13Rα2 from PCa-M CM increased the invasiveness of ARCaPM cells while siRNA directed against this receptor significantly reduced invasiveness of these cells in the presence of CM from PCa-M patients.

CONCLUSIONS

Thus, we show that circulating monocytes from metastatic PCa patients exert a tumor-promoting role via the secretion of CHI3L1, and CHI3L1 demands further exploration as a possible therapeutic target in advanced PCa.

Influence of YKL-40 gene RNA interference on the biological behaviors of endometrial cancer HEC-1A cells

The present study aimed to investigate the effects of chitinase-3-like protein 1 (YKL-40) gene RNA interference on the biological behaviors and enhanced chemosensitivity of endometrial cancer (EC) HEC-1A cells. YKL-40 small interfering (si)RNA was transduced into EC HEC-1A cells using a lentivirus. The experiment was divided into three groups: The experimental group was transfected with YKL-40 siRNA (si-YKL-40); the mock-treatment group was transfected with transfection reagent only; and the blank control group was left untreated. A reverse transcription-quantitative polymerase chain reaction was performed to investigate the mRNA expression levels of YKL-40. The biological behaviors, including cell proliferation, migration, invasion and apoptosis, were detected by MTT and Transwell assays, and flow cytometry (FCM) analysis, respectively. The results of the present study demonstrated that the mRNA expression levels of YKL-40 were downregulated within HEC-1A cells upon transfection with si-YKL-40 (P<0.05). The proliferative, migratory and invasive abilities of HEC-1A cells were inhibited by si-YKL-40 (P<0.05). The mRNA expression levels of YKL-40 were upregulated within HEC-1A cells following treatment with cisplatin (P<0.05). FCM analysis revealed that the average cellular apoptosis rate increased following the inhibition of YKL-40 gene expression via siRNA (P<0.05). Therefore, the YKL-40 gene may be associated with the proliferative, migratory, invasive and anti-apoptotic ability of HEC-1A cells. YKL-40 downregulation may enhance the sensitivity of human EC HEC-1A cells to chemotherapy.

CHI3L1 overexpression is associated with metastasis and is an indicator of poor prognosis in papillary thyroid carcinoma

OBJECTIVE

In this study, we examined the relationships between the expression level of CHI3L1 and the clinicopathological characteristics of papillary thyroid carcinoma.

METHODS

A total of 322 tissue samples from patients with papillary thyroid carcinoma were collected, and the CHI3L1 expression levels in tumor tissues, matched adjacent noncancerous tissues were detected using immunohistochemistry (IHC) and qRT-PCR. The relationships between CHI3L1 expression levels and the clinical characteristics were evaluated.

RESULTS

CHI3L1 expression was significantly increased in papillary thyroid carcinoma compared with matched adjacent noncancerous tissues (P< 0.001), tumor tissues with lymph node metastasis (LNM) compared with tumor tissues without LNM (P< 0.001) and tumor tissues with distant organ metastasis (DOM) compared with tumor tissues without DOM (P< 0.01). CHI3L1 expression was significantly associated with tumor size (P= 0.0001), lymph node metastasis (P< 0.0001), distant organ metastasis (P< 0.0001), extrathyroid invasion (P= 0.0022), vascular invasion (P= 0.0004) and TNM stage (P= 0.0001). CHI3L1 overexpression in papillary thyroid carcinoma tissues correlates with the tumor malignant potential (P< 0.01). More importantly, Cox multifactor analysis indicated that patients with high CHI3L1 expression have lower overall survival, disease-free survival, lymph node recurrence-free survival, and distant recurrence free survival rates than those with low expression (P< 0.05). And our findings were further validated by online Oncomine database.

CONCLUSIONS

CHI3L1 is associated with tumor metastasis and might be a prognostic biomarker for papillary thyroid carcinoma.

Tumor-recruited M2 macrophages promote gastric and breast cancer metastasis via M2 macrophage-secreted CHI3L1 protein

BACKGROUND

The macrophage, one of the several key immune cell types, is believed to be involved in tumorigenesis. However, the mechanism of macrophages promoting tumor progression is largely unknown.

METHODS

The differentially secreted proteins of M1 and M2 macrophages were analyzed by mass spectrometry. We performed GST pull-down assay for the identification of cell-membrane receptors that interact with chitinase 3-like protein 1 (CHI3L1) protein. The mouse model was used to validate the function of CHI3L1 in cancer metastasis in vivo. Protein phosphorylation and gene expression were performed to study the signaling pathway activation of cancer cells after CHI3L1 treatment.

RESULTS

M2 macrophage-secreted CHI3L1 promoted the metastasis of gastric and breast cancer cells in vitro and in vivo. The CHI3L1 protein functioned by interacting with interleukin-13 receptor α2 chain (IL-13Rα2) molecules on the plasma membranes of cancer cells. Activation of IL-13Rα2 by CHI3L1 triggered the activation of the mitogen-activated protein kinase signaling pathway, leading to the upregulated expression of matrix metalloproteinase genes, which promoted tumor metastasis. The results of this study indicated that the level of CHI3L1 protein in the sera of patients with gastric or breast cancer was significantly elevated compared with those of healthy donors.

CONCLUSIONS

Our study revealed a novel aspect of macrophages with respect to cancer metastasis and showed that CHI3L1 could be a marker of metastatic gastric and breast cancer in patients.

Dendritic cells serve as a "Trojan horse" for oncolytic adenovirus delivery in the treatment of mouse prostate cancer

AIM

Adenovirus-mediated gene therapy is a novel therapeutic approach for the treatment of cancer, in which replication of the virus itself is the anticancer method. However, the success of this novel therapy is limited due to inefficient delivery of the virus to the target sites. In this study, we used dendritic cells (DCs) as carriers for conditionally replicating adenoviruses (CRAds) in targeting prostate carcinoma (PCa).

METHODS

Four types of CRAds, including Ad-PC (without PCa-specific promoter and a recombinant human tumor necrosis factor, rmhTNF, sequence), Ad-PC-rmhTNF (without PCa-specific promoter), Ad-PPC-NCS (without an rmhTNF sequence) and Ad-PPC-rmhTNF, were constructed. The androgen-insensitive mouse PCa RM-1 cells were co-cultured with CRAd-loading DCs, and the viability of RM-1 cells was examined using MTT assay. The in vivo effects of CRAd-loading DCs on PCa were evaluated in RM-1 xenograft mouse model.

RESULTS

Two PCa-specific CRAds (Ad-PPC-NCS, Ad-PPC-rmhTNF) exhibited more potent suppression on the viability of RM-1 cells in vitro than the PCa-non-specific CRAds (Ad-PC, Ad-PC-rmhTNF). In PCa-bearing mice, intravenous injection of the PCa-specific CRAd-loading DCs significantly inhibited the growth of xenografted tumors, extended the survival time, and induced T-cell activation. Additionally, the rmhTNF-containing CRAds exhibited greater tumor killing ability than CRAds without rmhTNF.

CONCLUSION

DCs may be an effective vector for the delivery of CRAds in the treatment of PCa.

Chitinase-3-like-1/YKL-40 as marker of circulating tumor cells

Ex vivo expansion of circulating tumor cells (CTCs) of small cell lung cancer (SCLC) patients enabled systematic screening of secreted cytokines. Permanent CTC cultures of different patients shared secretion of chitinase-3-like-1 (CHI3L1)/YKL-40, known to be upregulated in a range of tumor entities and to be associated with increased metastasis and decreased survival. This protein lacks enzymatic activity and its mechanism of promoting tumor dissemination has not been resolved. Results from SCLC CTC cultures suggest CHI3L1 as marker and important effector of tumor cell dissemination in the peripheral blood. Furthermore, this protein may link chronic inflammation of the lung, chronic obstructive pulmonary disease (COPD) and lung cancer.