Organ-specific inhibition of metastatic colon carcinoma by CXCR3 antagonism

The role of CXC chemokines and receptors in breast cancer

CXC chemokines are a class of cytokines possessing chemotactic properties. Studies indicate that CXC chemokines exhibit dysregulation in miscellaneous cancer categories and are significantly associated with the advancement of tumors. Breast cancer is a commonly diagnosed and fatal cancer among the female population. Breast cancer pathogenesis and progression involve various mechanisms, including invasion, metastasis, angiogenesis, and inflammation. Chemokines and their receptors are involved in all of these processes. The CXC chemokine receptors (CXCRs) and their related ligands have attracted considerable attention due to their multifaceted functions in facilitating and controlling tumor proliferation. CXCRs are expressed by both cancer cells and immune cells, and they play a crucial role in regulating the tumor microenvironment and the immune response. This review aims to assess the potential of CXCRs and CXC chemokines as therapeutic targets or biomarkers for personalized therapy. Additionally, it provides an overview of the current understanding of the expression, function, and prognostic relevance of CXCRs in breast cancer. Furthermore, the challenges and potential prospects pertaining to CXCR investigation in breast cancer are deliberated.

Lung-specific metastasis: the coevolution of tumor cells and lung microenvironment

The vast majority of cancer-related deaths are attributed to metastasis. The lung, being a common site for cancer metastasis, is highly prone to being a target for multiple cancer types and causes a heavy disease burden. Accumulating evidence has demonstrated that tumor metastasis necessitates continuous interactions between tumor cells and distant metastatic niches. Nevertheless, a comprehensive elucidation of the underlying mechanisms governing lung-specific metastasis still poses a formidable challenge. In this review, we depict the lung susceptibility and the molecular profiles of tumors with the potential for lung metastasis. Under the conceptual framework of "Reciprocal Tumor-Lung Metastatic Symbiosis" (RTLMS), we mechanistically delineate the bidirectional regulatory dynamics and coevolutionary adaptation between tumor cells and distal pulmonary niches during lung-specific metastasis, including the induction of pre-metastatic-niches, positive responses of the lung, tumor colonization, dormancy, and reawakening. An enhanced understanding of the latest mechanisms is essential for developing targeted strategies to counteract lung-specific metastasis.

A patent review of CXCR7 modulators (2019-present)

INTRODUCTION

Atypical chemokine receptor 3 (ACKR3) (formerly CXCR7) regulates various biological processes through its ligands and is closely associated with numerous diseases, including inflammation, cancer, cardiovascular diseases (CVDs), pain, and neurological disorders. Therefore, ACKR3 has emerged as a potential target for disease treatment.

AREAS COVERED

This review summarizes the ACKR3 modulators published in patents from 2019 to 2024 using data from Google Patents, the European Patent Office, and the World Intellectual Property Organization's online databases. This includes information on their chemical structures, syntheses, activities, and developmental stages.

EXPERT OPINION

ACKR3 agonists gained traction as a treatment for cardiovascular and pain conditions. WW-12, which was derived from the chemical modifications of conolidine, became a novel small-molecule pain modulator by activating ACKR3, which in turn boosted endogenous opioid peptides for the classical opioid receptors.ACKR3 antagonist ACT-1004-1239 from Idorsia Pharmaceuticals Ltd. has demonstrated the ability to treat cancer, acute lung injury/ARDS, and autoimmune diseases, including multiple sclerosis. The outcomes of these clinical trials will direct the development and indications of future ACKR3 modulators.

Adipocyte-derived CXCL10 in obesity promotes the migration and invasion of ovarian cancer cells

BACKGROUND

As a widespread epidemic, obesity poses a significant risk to health and leads to physiological abnormalities, including diabetes mellitus and inflammation. Obesity-induced inflammation can accelerate the development of various cancers; however, the role of obesity in the migration of ovarian carcinoma is still unclear.

RESULTS

Twenty-four commonly upregulated genes were identified from single-cell RNA sequencing datasets of both ovarian carcinoma and adipose tissue of obese humans, with the chemokine CXCL10 showing a significant increase in adipose tissues associated with obesity. And CXCL10 treated primed macrophages exhibit both direct and indirect effects on the proliferation, apoptosis, migration, and invasion of ovarian adenocarcinoma cells. The treatment of CXCL10 on the SKOV3 cells enhances FAK expression and phosphorylation, thereby accelerating the migration and invasion of ovarian cancer cells. Conditioned medium-derived from CXCL10-treated THP-1 cells significantly promoted ovarian cancer cell migration and invasion, which may be attributed to the increased expression of C1QA, C1QC, CCL24, and IL4R in macrophages.

CONCLUSIONS

Obesity exacerbates the production of CXCL10 from adipose tissues in obese women. CXCL10 is a key hub factor between developments of ovarian cancer and adipose tissues in obese. Targeting adipose-derived CXCL10 or its downstream macrophages may be a potential strategy to alleviate ovarian cancer accompanied by obesity.

Exploring causal correlations between inflammatory cytokines and colorectal cancer: A 2-sample Mendelian randomization study

Colorectal cancer (CRC) is a significant global public health concern. Several observational studies have examined the association between inflammatory cytokines and the risk of colorectal cancer, but the findings have been inconsistent. In this study, we employed a 2-sample Mendelian randomization (MR) analysis, primarily using the inverse variance weighted approach, to investigate the causal relationship between inflammatory cytokines and CRC. The forward MR analysis revealed a positive association between higher levels of interleukin (IL)-16 (OR: 1.37, P = .002), vascular endothelial growth factor (OR: 1.44, P = .001), and MIG (OR: 1.23, P = .040) with an increased risk of rectal cancer. Conversely, higher levels of macrophage colony-stimulating factor (OR: 0.80, P = .010) may potentially decrease the risk of colon cancer. In the reverse MR analysis, it was found that rectal cancer is linked to higher levels of IL-1b (OR: 0.93, P = .022), IL-1ra (OR: 0.90, P = .001), IL-5 (OR: 0.93, P = .022), IL-9 (OR: 0.93, P = .017), and TNF-a (OR: 0.91, P = .003). Additionally, colon cancer is associated with elevated levels of FGF-Basic (OR: 1.10, P = .028). Consistent results were also found in MR-Egger, weighted median, and weighted mode analysis. Our study presents novel evidence supporting the causal relationship between inflammatory cytokines and CRC.

A microphysiological assay for studying T-cell chemotaxis, trafficking and tumor killing

Tumors in patients non-responsive to immunotherapy harbor a series of barriers that impede the efficacy of effector T-cells. Consequently, therapeutically modulating the chemotaxis machinery to enable effector T cell infiltration and function in the tumor could result in more successful therapeutic outcomes. Complexin-vitromodels allow re-creation ofin-vivotumor complexities in anin-vitrosetting, allowing improved translatability to patient biology at the laboratory scale. We identified a gap in available industrial scale microphysiological (MPS) assays for faster validation of targets and strategies that enable T-cell chemotaxis and effector function within tumor microenvironments. Using a commercially available, 96-chip 2-lane microfluidic assay system, we present a novel, scalable, complexin vitroMPS assay to study 3D T-cell chemotaxis and function within native, extracellular matrix (ECM)-rich multicellular tumor environments. Activated or naïve CD3+ T-cells stained with far-red nuclear stain responded to the chemokine gradients generated within the matrigel-collagen ECM by migrating into the microfluidic channel (∼5 mm horizontal window), in a concentration- and cell type-dependent manner. Furthermore, we observed and tracked chemotaxis and cancer cell killing function of antigen-specific CD4.CD8. chimeric antigen receptor (CAR)-T cells that responded to CXCR3 agonist gradient built through the expansive 5 mm of cancer cell colony containing stroma. The 2-lane assay system yielded useful information regarding donor and dose-dependent differences in CAR-T cell chemotaxis and tumor killing. The scalable assay system allows a granular window into immune cell migration and function in tissue spaces beyond endothelium, addressing a missing gap in studying tissue-specific immune cell chemotaxis and function to bring forward advancements in cancer immunotherapy.

Ubiquitin Ligase TRIM22 Inhibits Ovarian Cancer Malignancy via TCF4 Degradation

Ovarian cancer is one of the most common malignancies in women. Tripartite motif-containing protein 22 (TRIM22) plays an important role in the initiation and progression of malignant tumors. Similarly, the transcription factor 4 (TCF4) is an essential factor involved in the initiation and progression of many tumors. However, it is still unclear whether TRIM22 can affect TCF4 in ovarian cancer. Therefore, this study aims to investigate the mechanism related to TRIM22 and TCF4 in ovarian cancer. TRIM22 protein and mRNA levels were analyzed in samples from clinical and cell lines. The effects of TRIM22 knockdown and overexpression on cell proliferation, colony formation, migration, invasion, and related biomarkers were evaluated. In addition, the role of ubiquitination-mediated degradation of TCF4 was investigated by qRT-PCR and Western blotting. The association between TRIM22 and TCF4 was evaluated by Western blotting, coimmunoprecipitation, proliferation, colony formation, invasion, migration, and related biomarkers. The results showed that the expression of TRIM22 was minimal in ovarian cancer tissues. Furthermore, upregulation of TRIM22 significantly inhibited ovarian cancer cell proliferation, colony formation, migration, and invasion. In addition, TRIM22 was observed to regulate the degradation of TCF4 through the ubiquitination pathway. TCF4 can reverse the effects of TRIM22 on proliferation, colony formation, migration, and invasion in ovarian cancer cells. TRIM22-mediated ubiquitination of TCF4 at K48 is facilitated by the RING domain. Implications: In conclusion, ubiquitination of TCF4 protein in ovarian cancer is regulated by TRIM22, which has the potential to limit the proliferation, migration, and invasion of ovarian cancer.

Altered expression of cytokines, chemokines, growth factors, and soluble receptors in patients with colorectal cancer, and correlation with treatment outcome

Insofar as they play an important role in the pathogenesis of colorectal cancer (CRC), this study analyzes the serum profile of cytokines, chemokines, growth factors, and soluble receptors in patients with CRC and cancer-free controls as possible CRC signatures. Serum levels of 65 analytes were measured in patients with CRC and age- and sex-matched cancer-free controls using the ProcartaPlex Human Immune Monitoring 65-Plex Panel. Of the 65 tested analytes, 8 cytokines (CSF-3, IFN-γ, IL-12p70, IL-18, IL-20, MIF, TNF-α and TSLP), 8 chemokines (fractalkine, MIP-1β, BLC, Eotaxin-1, Eotaxin-2, IP-10, MIP-1a, MIP-3a), 2 growth factors (FGF-2, MMP-1), and 4 soluble receptors (APRIL, CD30, TNFRII, and TWEAK), were differentially expressed in CRC. ROC analysis confirmed the high association of TNF-α, BLC, Eotaxin-1, APRIL, and Tweak with AUC > 0.70, suggesting theranostic application. The expression of IFN-γ, IL-18, MIF, BLC, Eotaxin-1, Eotaxin-2, IP-10, and MMP1 was lower in metastatic compared to non-metastatic CRC; only AUC of MIF and MIP-1β were > 0.7. Moreover, MDC, IL-7, MIF, IL-21, and TNF-α are positively associated with tolerance to CRC chemotherapy (CT) (AUC > 0.7), whereas IL-31, Fractalkine, Eotaxin-1, and Eotaxin-2 were positively associated with resistance to CT. TNF-α, BLC, Eotaxin-1, APRIL, and Tweak may be used as first-line early detection of CRC. The variable levels of MIF and MIP-1β between metastatic and non-metastatic cases assign prognostic nature to these factors in CRC progression. Regarding tolerance to CT, MDC, IL-7, MIF, IL-21, and TNF-α are key when down-regulated or resistant to treatment is observed.

Role of chemokine receptors in gastrointestinal mucosa

Chemokine receptors are essential for the immune response in the oral and gut mucosa. The gastrointestinal mucosa is characterized by the presence of immune populations because it is susceptible to inflammatory and infectious diseases, necessitating immune surveillance. Chemokine receptors are expressed on immune cells and play a role in gastrointestinal tissue-homing, although other non-immune cells also express them for various biological functions. CCR9, CXCR3 and CXCR6 play an important role in the T cell response in inflammatory and neoplastic conditions of the gastrointestinal mucosa. However, CXCR6 could also be found in gastric cancer cells, highlighting the different roles of chemokine receptors in different pathologies. On the other hand, CCR4 and CCR8 are critical for Treg migration in gastrointestinal tissues, correlating with poor prognosis in mucosal cancers. Other chemokine receptors are also important in promoting myeloid infiltration with context-dependent roles. Further, CXCR4 and CXCR7 are also present in gastrointestinal tumor cells and are known to stimulate proliferation, migration, and invasion into other tissues, among other pro-tumorigenic functions. Determining the processes underlying mucosal immunity and creating tailored therapeutic approaches for gastrointestinal diseases requires an understanding of the complex interactions that occur between chemokine receptors and their ligands in these mucosal tissues.

CXCL10 could be a prognostic and immunological biomarker in bladder cancer

INTRODUCTION

As proteins that promote immune cell differentiation, chemokines have attracted great interest regarding their role in anti-tumor immune responses within the cancer environment. However, the exact role of CXCL10, a chemokine, in bladder cancer (BLCA) is still not fully elucidated.

METHOD

In the present study, we employed bioinformatics approaches to examine the expression pattern, prognostic value, and immune infiltration of CXCL10 in BLCA. Furthermore, we focused on examining the impact of CXCL10 on immune therapy in BLCA. Additionally, we validated the expression of CXCL10 in various BLCA cell lines using PCR techniques.

RESULTS

We observed an upregulation of CXCL10 in BLCA tissues as well as in different cell lines. Additionally, upregulation of CXCL10 indicates a better prognosis for BLCA patients. ESTIMATE and CIBERSORT algorithms suggest that CXCL10 is closely associated with the immune microenvironment of BLCA. Through multiple immune therapy cohorts, we also identified that CXCL10 has shown promising predictive value for assessing the efficacy of immune therapy in in BLCA.

CONCLUSION

Our study indicates that CXCL10 has the potential to serve as a favorable prognostic factor and is strongly associated with immune infiltration in BLCA.

Chemotactic signaling pathways in prostate cancer: Implications in the tumor microenvironment and as potential therapeutic targets

Prostate cancer (PCa) stands as a significant global health concern, ranking among the leading causes of cancer deaths in men. While there are several treatment modalities for localized PCa, metastatic castration-resistant PCa (mCRPC) remains incurable. Despite therapeutic advancements showing promise in mCRPC, their impact on overall survival has been limited. This chapter explores the process by which tumors form, reviews our current understanding of PCa progression to mCRPC, and addresses the challenges of boosting anti-tumor immune responses in these tumors. It specifically discusses how chemotactic signaling affects the tumor microenvironment and its role in immune evasion and cancer progression. The chapter further examines the rationale of directly or indirectly targeting these pathways as adjuvant therapies for mCRPC, highlighting recent pre-clinical and clinical studies currently underway. The discussion emphasizes the potential of targeting specific chemokines and chemokine receptors as combination therapies with mainstream treatments for PCa and mCRPC to maximize long-term survival for this deadly disease.

The role of stromal cells in epithelial-mesenchymal plasticity and its therapeutic potential

The epithelial-mesenchymal transition (EMT) is a critical tumor invasion and metastasis process. EMT enables tumor cells to migrate, detach from their original location, enter the circulation, circulate within it, and eventually exit from blood arteries to colonize in foreign sites, leading to the development of overt metastases, ultimately resulting in death. EMT is intimately tied to stromal cells around the tumor and is controlled by a range of cytokines secreted by stromal cells. This review summarizes recent research on stromal cell-mediated EMT in tumor invasion and metastasis. We also discuss the effects of various stromal cells on EMT induction and focus on the molecular mechanisms by which several significant stromal cells convert from foes to friends of cancer cells to fuel EMT processes via their secretions in the tumor microenvironment (TME). As a result, a better knowledge of the role of stromal cells in cancer cells' EMT may pave the path to cancer eradication.

Research progress of CXCR3 inhibitors

The human CXCR3 receptor was initially identified and cloned in the mid-1990s. In the process of understanding CXCR3, it gradually found that it plays an important role in the process of a variety of diseases, including inflammation, immune diseases, cancer, cardiovascular diseases, central nervous system diseases, etc., which attracted the attention of many researchers. Subsequently, some small molecule inhibitors targeting CXCR3 receptors were also developed. Unfortunately, no CXCR3 inhibitors have been approved for marketing by FDA. Up to now, only one CXCR3 small molecule inhibitor has entered the clinical trial stage, but it has not achieved ideal results in the end. Therefore, there is still much to think about and explore for the development of CXCR3 inhibitors. This article reviews the important role of CXCR3 in various physiological and pathological processes and some small molecule inhibitors of CXCR3.

Systemic immunological profile of children with B-cell acute lymphoblastic leukemia: performance of cell populations and soluble mediators as serum biomarkers

Background

Children with B-cell acute lymphoblastic leukemia (B-ALL) have an immune imbalance that is marked by remodeling of the hematopoietic compartment, with effects on peripheral blood (PB). Although the bone marrow (BM) is the main maintenance site of malignancy, the frequency with which immune cells and molecules can be monitored is limited, thus the identification of biomarkers in PB becomes an alternative for monitoring the evolution of the disease.

Methods

Here, we characterize the systemic immunological profile in children undergoing treatment for B-ALL, and evaluate the performance of cell populations, chemokines and cytokines as potential biomarkers during clinical follow-up. For this purpose, PB samples from 20 patients with B-ALL were collected on diagnosis (D0) and during induction therapy (days 8, 15 and 35). In addition, samples from 28 children were used as a control group (CG). The cellular profile (NK and NKT-cells, Treg, CD3+ T, CD4+ T and CD8+ T cells) and soluble immunological mediators (CXCL8, CCL2, CXCL9, CCL5, CXCL10, IL-6, TNF, IFN-γ, IL-17A, IL- 4, IL-10 and IL-2) were evaluated via flow cytometry immunophenotyping and cytometric bead array assay.

Results

On D0, B-ALL patients showed reduction in the frequency of cell populations, except for CD4+ T and CD8+ T cells, which together with CCL2, CXCL9, CXCL10, IL-6 and IL-10 were elevated in relation to the patients of the CG. On D8 and D15, the patients presented a transition in the immunological profile. While, on D35, they already presented an opposite profile to D0, with an increase in NKT, CD3+ T, CD4+ T and Treg cells, along with CCL5, and a decrease in the levels of CXCL9, CXCL10 and IL-10, thus demonstrating that B-ALL patients present a complex and dynamic immune network during induction therapy. Furthermore, we identified that many immunological mediators could be used to classify the therapeutic response based on currently used parameters.

Conclusion

Finally, it is noted that the systemic immunological profile after remission induction still differs significantly when compared to the GC and that multiple immunological mediators performed well as serum biomarkers.

A Network Landscape of HPVOPC Reveals Methylation Alterations as Significant Drivers of Gene Expression via an Immune-Mediated GPCR Signal

HPV-associated oropharynx carcinoma (HPVOPC) tumors have a relatively low mutational burden. Elucidating the relative contributions of other tumor alterations, such as DNA methylation alterations, alternative splicing events (ASE), and copy number variation (CNV), could provide a deeper understanding of carcinogenesis drivers in this disease. We applied network propagation analysis to multiple classes of tumor alterations in a discovery cohort of 46 primary HPVOPC tumors and 25 cancer-unaffected controls and validated our findings with TCGA data. We identified significant overlap between differential gene expression networks and all alteration classes, and this association was highest for methylation and lowest for CNV. Significant overlap was seen for gene clusters of G protein-coupled receptor (GPCR) pathways. HPV16-human protein interaction analysis identified an enriched cluster defined by an immune-mediated GPCR signal, including CXCR3 cytokines CXCL9, CXCL10, and CXCL11. CXCR3 was found to be expressed in primary HPVOPC, and scRNA-seq analysis demonstrated CXCR3 ligands to be highly expressed in M2 macrophages. In vivo models demonstrated decreased tumor growth with antagonism of the CXCR3 receptor in immunodeficient but not immunocompetent mice, suggesting that the CXCR3 axis can drive tumor proliferation in an autocrine fashion, but the effect is tempered by an intact immune system. In conclusion, methylation, ASE, and SNV alterations are highly associated with network gene expression changes in HPVOPC, suggesting that ASE and methylation alterations have an important role in driving the oncogenic phenotype. Network analysis identifies GPCR networks, specifically the CXCR3 chemokine axis, as modulators of tumor-immune interactions that may have proliferative effects on primary tumors as well as a role for immunosurveillance; however, CXCR3 inhibition should be used with caution, as these agents may both inhibit and stimulate tumor growth considering the competing effects of this cytokine axis. Further investigation is needed to explore opportunities for targeted therapy in this setting.

Single-cell data analysis of malignant epithelial cell heterogeneity in lung adenocarcinoma for patient classification and prognosis prediction

Lung cancer is one of the leading causes of cancer-related death. Most advanced lung adenocarcinoma (LUAD) patients have poor survival because of drug resistance and relapse. Neglecting intratumoral heterogeneity might be one of the reasons for treatment insensitivity, while single-cell RNA sequencing (scRNA-seq) technologies can provide transcriptome information at the single-cell level. Herein, we combined scRNA-seq and bulk RNA-seq data of LUAD and identified a novel cluster of malignant epithelial cells - KRT81+ malignant epithelial cells - associated with worse prognoses. Further analysis revealed that the hypoxia and EMT pathways of these cells were activated to predispose them to differentiate into metastatic lung adenocarcinoma cells. Finally, we also studied the role of these tumor cells in the immune microenvironment and their role in the classification and prognosis prediction of lung adenocarcinoma patients.

Targeting CXCL9/10/11-CXCR3 axis: an important component of tumor-promoting and antitumor immunity

Chemokines are chemotactic-competent molecules composed of a family of small cytokines, playing a key role in regulating tumor progression. The roles of chemokines in antitumor immune responses are of great interest. CXCL9, CXCL10, and CXCL11 are important members of chemokines. It has been widely investigated that these three chemokines can bind to their common receptor CXCR3 and regulate the differentiation, migration, and tumor infiltration of immune cells, directly or indirectly affecting tumor growth and metastasis. Here, we summarize the mechanism of how the CXCL9/10/11-CXCR3 axis affects the tumor microenvironment, and list the latest researches to find out how this axis predicts the prognosis of different cancers. In addition, immunotherapy improves the survival of tumor patients, but some patients show drug resistance. Studies have found that the regulation of CXCL9/10/11-CXCR3 on the tumor microenvironment is involved in the process of changing immunotherapy resistance. Here we also describe new approaches to restoring sensitivity to immune checkpoint inhibitors through the CXCL9/10/11-CXCR3 axis.

GPx3 knockdown inhibits the proliferation and DNA synthesis and enhances the early apoptosis of human spermatogonial stem cells via mediating CXCL10 and cyclin B1

Spermatogenesis is regulated by genetic and epigenetic factors. However, the genes and signaling pathways mediating human spermatogenesis remain largely unknown. Here, we have for the first time explored the expression, function, and mechanism of glutathione peroxidase 3 (GPx3) in controlling the proliferation and apoptosis of human spermatogonial stem cells (SSCs). We found that GPx3 was expressed in human SSCs. Notably, we revealed that GPx3 knockdown resulted in the decrease in the proliferation, DNA synthesis, and cyclin B1 level in human SSC lines, which possessed the phenotypic features of human primary SSCs. Flow cytometry and TUNEL assays showed that GPx3 silencing led to enhancement of early apoptosis of human SSC line. RNA sequencing was utilized to identify CXCL10 as a target of GPx3 in human SSCs, and notably, both double immunostaining and co-immunoprecipitation (co-IP) demonstrated that there was an association between GPx3 and CXCL10 in these cells. CXCL10-shRNA resulted in the reduction in the proliferation and DNA synthesis of human SSC line and an increase in apoptosis of these cells. Taken together, these results implicate that GPx3 regulates the proliferation, DNA synthesis, and early apoptosis of human SSC line via mediating CXCL10 and cyclin B1. This study, thus, offers a novel insight into the molecular mechanism regulating the fate determinations of human SSCs and human spermatogenesis.

Autotaxin Inhibition with IOA-289 Decreases Breast Tumor Growth in Mice Whereas Knockout of Autotaxin in Adipocytes Does Not

Breast cancer cells produce negligible quantities of autotaxin. Instead, previous work indicated that adipocytes in the inflamed adipose tissue adjacent to breast tumors are a major source of autotaxin secretion that drives breast tumor growth, metastasis, and the loss of efficacy for chemotherapy and radiotherapy. To test this hypothesis, we used mice with an adipocyte-specific knock out of autotaxin. The lack of autotaxin secretion from adipocytes failed to decrease the growth of orthotopic E0771 breast tumors in syngeneic C57BL/6 mice and the growth and lung metastasis of spontaneous breast tumors in MMTV-PyMT mice. However, the inhibition of autotaxin with IOA-289 decreased the growth of E0771 tumors, indicating that another source of autotaxin is responsible for tumor growth. Tumor-associated fibroblasts and leukocytes produce the majority of autotoxin transcripts in the E0771 breast tumors, and we hypothesize that they are the main sources of ATX that drive breast tumor growth. Autotaxin inhibition with IOA-289 increased the numbers of CD8α+-T-cells in the tumors. This was accompanied by decreases in the concentrations of CXCL10, CCL2, and CXCL9 in the plasma and LIF, TGFβ1, TGFβ2, and prolactin in the tumors. Bioinformatics analysis of human breast tumor databases showed that autotaxin (ENPP2) is expressed mainly in endothelial cells and fibroblasts. Autotaxin expression correlated significantly with increases in IL-6 cytokine receptor ligand interactions, signaling by LIF, TGFβ, and prolactin. This confirms the relevance of results from autotaxin inhibition in the mouse model. We propose that inhibiting autotaxin activity that is derived from cells presenting breast tumors such as fibroblasts, leukocytes, or endothelial cells changes the tumor micro-environment in such a way as to inhibit tumor growth.

Metastasis prevention: How to catch metastatic seeds

Despite considerable advances in the evolution of anticancer therapies, metastasis still remains the main cause of cancer mortality. Therefore, current strategies for cancer cure should be redirected towards prevention of metastasis. Targeting metastatic pathways represents a promising therapeutic opportunity aimed at obstructing tumor cell dissemination and metastatic colonization. In this review, we focus on preclinical studies and clinical trials over the last five years that showed high efficacy in suppressing metastasis through targeting lymph node dissemination, tumor cell extravasation, reactive oxygen species, pre-metastatic niche, exosome machinery, and dormancy.

Review of biomarkers for response to immunotherapy in HNSCC microenvironment

Head and neck squamous cell carcinoma are one of the most common types of cancer worldwide. Although a variety of treatment methods such as surgery, radiotherapy, chemotherapy, and targeted therapy are widely used in diagnosing and treating HNSCC, the survival prognosis of patients has not been significantly improved in the past decades. As an emerging treatment approach, immunotherapy has shown exciting therapeutic effects in R/M HNSCC. However, the current screening methods are still insufficient, and there is a significant need for reliable predictive biomarkers for personalized clinical management and new therapeutic strategies. This review summarized the application of immunotherapy in HNSCC, comprehensively analyzed the existing bioinformatic studies on immunotherapy in HNSCC, evaluated the current methods of tumor immune heterogeneity and immunotherapy, and aimed to screen molecular markers with potential predictive significance. Among them, PD-1 has obvious predictive relevance as the target of existing immune drugs. Clonal TMB is a potential biomarker for HNSCC immunotherapy. The other molecules, including IFN-γ, CXCL, CTLA-4, MTAP, SFR4/CPXM1/COL5A1, TILs, CAFs, exosomes, and peripheral blood indicators, may have suggestive significance for tumor immune microenvironment and prognosis of immunotherapy.

CXCR3 Inhibition Blocks the NF-κB Signaling Pathway by Elevating Autophagy to Ameliorate Lipopolysaccharide-Induced Intestinal Dysfunction in Mice

Autophagy is a cellular catabolic process in the evolutionarily conservative turnover of intracellular substances in eukaryotes, which is involved in both immune homeostasis and injury repairment. CXCR3 is an interferon-induced chemokine receptor that participates in immune regulation and inflammatory responses. However, CXCR3 regulating intestine injury via autophagy along with the precise underlying mechanism have yet to be elucidated. In the current study, we employed an LPS-induced inflammatory mouse model and confirmed that CXCR3 knockout significantly attenuates intestinal mucosal structural damage and increases tight junction protein expression. CXCR3 knockout alleviated the LPS-induced increase in the expression of inflammatory factors including TNF-α, IL-6, p-65, and JNK-1 and enhanced autophagy by elevating LC3II, ATG12, and PINK1/Parkin expression. Mechanistically, the function of CXCR3 regarding autophagy and immunity was investigated in IPEC-J2 cells. CXCR3 inhibition by AMG487 enhanced autophagy and reduced the inflammatory response, as well as blocked the NF-κB signaling pathway and elevated the expression of the tight junction protein marker Claudin-1. Correspondingly, these effects were abolished by autophagy inhibition with the selective blocker, 3-MA. Moreover, the immunofluorescence assay results further demonstrated that CXCR3 inhibition-mediated autophagy blocked p65 nuclear translocation, and the majority of Claudin-1 was located at the tight junctions. In conclusion, CXCR3 inhibition reversed LPS-induced intestinal barrier damage and alleviated the NF-κB signaling pathway via enhancing autophagy. These data provided a theoretical basis for elucidating the immunoregulatory mechanism by targeting CXCR3 to prevent intestinal dysfunction.

The role of CXCR3 and its ligands in cancer

Chemokines are a class of small cytokines or signaling proteins that are secreted by cells. Owing to their ability to induce directional chemotaxis of nearby responding cells, they are called chemotactic cytokines. Chemokines and chemokine receptors have now been shown to influence many cellular functions, including survival, adhesion, invasion, and proliferation, and regulate chemokine levels. Most malignant tumors express one or more chemokine receptors. The CXC subgroup of chemokine receptors, CXCR3, is mainly expressed on the surface of activated T cells, B cells, and natural killer cells, and plays an essential role in infection, autoimmune diseases, and tumor immunity by binding to specific receptors on target cell membranes to induce targeted migration and immune responses. It is vital to treat infections, autoimmune diseases, and tumors. CXCR3 and its ligands, CXCL9, CXCL10, and CXCL11, are closely associated with the development and progression of many tumors. With the elucidation of its mechanism of action, CXCR3 is expected to become a new indicator for evaluating the prognosis of patients with tumors and a new target for clinical tumor immunotherapy. This article reviews the significance and mechanism of action of the chemokine receptor CXCR3 and its specific ligands in tumor development.

CXC chemokine ligand-10 promotes the accumulation of monocyte-like myeloid-derived suppressor cells by activating p38 MAPK signaling under tumor conditions

CXC chemokine ligand-10 (CXCL10) is a small (10 kDa) secretory protein in the CXC subfamily of cytokines. CXCL10 has been reported to play an important role in antitumor immunity as a chemotactic factor. Tumor development is always accompanied by the formation of an immunosuppressive tumor microenvironment, and the role of CXCL10 in tumor immunosuppression remains unclear. Here, we reported that CXCL10 expression was significantly upregulated in mice with melanoma, and tumor cells secreted large amounts of CXCL10. Myeloid-derived suppressor cells (MDSCs) are an important part of the immunosuppressive tumor microenvironment. Our results showed that CXCL10 promoted the proliferation of monocyte-like (mo)-MDSCs by activating the p38 MAPK signaling pathway through CXCR3, which led to the abnormal accumulation of mo-MDSCs under tumor conditions. This finding provides a new understanding of the mechanism by which a tumor-induced immunosuppressive microenvironment forms and suggests that CXCL10 could be a potential intervention target for slowing tumor progression.

Bioinformatics analysis of the circRNA-miRNA-mRNA network for atrial fibrillation

Atrial fibrillation (AF) is a chronic and progressive disease, with advancing age, the morbidity of which will increase exponentially. Circular ribonucleic acids (RNAs; circRNAs) have gained a growing attention in the development of AF in recent years. The purpose of this study is to explore the mechanism of circRNA regulation in AF, in particular, the intricate interactions among circRNA, microRNA (miRNA), and messenger RNA (mRNA). Three datasets (GSE129409, GSE68475, and GSE79768) were obtained from the Gene Expression Omnibus database to screen differentially expressed (DE) circRNAs, DE miRNAs, and DE mRNAs in AF, respectively. Based on circRNA-miRNA pairs and miRNA-mRNA pairs, a competing endogenous RNAs (ceRNAs) network was built. Then, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analysis of DE mRNAs in the network were performed and protein-protein interaction (PPI) networks were established to identify hub genes. Finally, a circRNA-miRNA-hub gene subnetwork was constructed. A total of 103 DE circRNAs, 16 DE miRNAs, and 110 DE mRNAs were screened in AF. Next, ceRNAs network in AF was constructed with 3 upregulated circRNAs, 2 downregulated circRNAs, 2 upregulated miRNAs, 2 downregulated miRNAs, 17 upregulated mRNAs, and 24 downregulated mRNAs. Thirty GO terms and 6 KEGG pathways were obtained. Besides, 6 hub genes (C-X-C chemokine receptor type 4 [CXCR4], C-X-C chemokine receptor type 2 [CXCR2], C-X-C motif chemokine 11 [CXCL11], neuromedin-U, B1 bradykinin receptor, and complement C3) were screened from constructing a PPI network. Finally, a circRNA-miRNA-hub gene subnetwork with 10 regulatory axes was constructed to describe the interactions among the differential circRNAs, miRNA, and hub genes. We speculated that hsa_circRNA_0056281/hsa_circRNA_0006665 -hsa-miR-613-CXCR4/CXCR2/CXCL11 regulatory axes and hsa_circRNA_0003638-hsa-miR-1207-3p-CXCR4 regulatory axis may be associated with the pathogenesis of AF.

Pro-tumorigenic role of type 2 diabetes-induced cellular senescence in colorectal cancer

Colorectal cancer (CRC) is the second leading cause of cancer-related mortality worldwide. The disease still remains incurable and highly lethal in the advanced stage, representing a global health concern. Therefore, it is essential to understand the causes and risk factors leading to its development. Because age-related cellular senescence and type 2 diabetes (T2D) have been recognised as risk factors for CRC development, the recent finding that type 2 diabetic patients present an elevated circulating volume of senescent cells raises the question whether type 2 diabetes facilitates the process of CRC tumorigenesis by inducing premature cell senescence. In this review, we will discuss the mechanisms according to which T2D induces cellular senescence and the role of type 2 diabetes-induced cellular senescence in the pathogenesis and progression of colorectal cancer. Lastly, we will explore the current therapeutic approaches and challenges in targeting senescence.

Identification of CXCL10 and CXCL11 as the candidate genes involving the development of colitis-associated colorectal cancer

Background: Ulcerative colitis (UC) is a well-known risk factor for developing colitis-associated colorectal cancer (CAC). However, the molecular mechanism of the pathogenesis of CAC remains unclear. This study aimed to explore candidate genes involved in the tumorigenesis of CAC.

Methods: GSE75214 and the Cancer Genome Atlas Program (TCGA) dataset were used to analyze the differentially expressed genes (DEGs) in UC and colorectal cancer (CRC), respectively. Survival-hub genes were identified from these DEGs by sequentially constructing a protein–protein interaction network, selecting hub genes, and conducting survival analysis. Regulatory signatures were also predicted on these genes through the online database. Apc^min/+ and UC mice models were used to validate the expression of the above-predicted molecules. Gene set enrichment analysis and CIBERSORT were performed to explore the enriched molecular pathways and associated tissue-infiltrating immune cells of genes.

Results: Here, 376 common DEGs were identified from the GSE75214 and TCGA datasets. Through survival-hub gene selection and in vivo experiments, we confirmed that CXCL10 and CXCL11 were significantly upregulated in UC and CRC. We also proved that miR-34a-5p and miR-203a-5p were potential regulators of CXCL10 and CXCL11. Meanwhile, CXCL10 and CXCL11 may activate the JAK–STAT signaling pathway via the interaction with cytokine receptors in UC. Furthermore, CXCL10 and CXCL11 were positively associated with the tissue infiltration of proinflammatory M1 macrophages in UC and CRC.

Conclusion: CXCL10 and CXCL11 may act as the candidate genes involved in the tumorigenesis of CAC and potential therapeutic targets to prevent the development of CAC from UC.

Identification of cell types in multiplexed in situ images by combining protein expression and spatial information using CELESTA

Advances in multiplexed in situ imaging are revealing important insights in spatial biology. However, cell type identification remains a major challenge in imaging analysis, with most existing methods involving substantial manual assessment and subjective decisions for thousands of cells. We developed an unsupervised machine learning algorithm, CELESTA, which identifies the cell type of each cell, individually, using the cell's marker expression profile and, when needed, its spatial information. We demonstrate the performance of CELESTA on multiplexed immunofluorescence images of colorectal cancer and head and neck squamous cell carcinoma (HNSCC). Using the cell types identified by CELESTA, we identify tissue architecture associated with lymph node metastasis in HNSCC, and validate our findings in an independent cohort. By coupling our spatial analysis with single-cell RNA-sequencing data on proximal sections of the same specimens, we identify cell-cell crosstalk associated with lymph node metastasis, demonstrating the power of CELESTA to facilitate identification of clinically relevant interactions.

Role of chemokine systems in cancer and inflammatory diseases

Chemokines are a large family of small secreted proteins that have fundamental roles in organ development, normal physiology, and immune responses upon binding to their corresponding receptors. The primary functions of chemokines are to coordinate and recruit immune cells to and from tissues and to participate in regulating interactions between immune cells. In addition to the generally recognized antimicrobial immunity, the chemokine/chemokine receptor axis also exerts a tumorigenic function in many different cancer models and is involved in the formation of immunosuppressive and protective tumor microenvironment (TME), making them potential prognostic markers for various hematologic and solid tumors. In fact, apart from its vital role in tumors, almost all inflammatory diseases involve chemokines and their receptors in one way or another. Modulating the expression of chemokines and/or their corresponding receptors on tumor cells or immune cells provides the basis for the exploitation of new drugs for clinical evaluation in the treatment of related diseases. Here, we summarize recent advances of chemokine systems in protumor and antitumor immune responses and discuss the prevailing understanding of how the chemokine system operates in inflammatory diseases. In this review, we also emphatically highlight the complexity of the chemokine system and explore its potential to guide the treatment of cancer and inflammatory diseases.

Integrative Analysis of Biomarkers and Mechanisms in Adamantinomatous Craniopharyngioma

Craniopharyngioma is a benign tumor, and the predominant treatment methods are surgical resection and radiotherapy. However, both treatments may lead to complex complications, seriously affecting patients’ survival rate and quality of life. Adamantinomatous craniopharyngioma (ACP), as one of the histological subtypes of craniopharyngioma, is associated with a high incidence and poor prognosis, and there is a gap in the targeted therapy of immune-related genes for ACP. In this study, two gene expression profiles of ACP, namely GSE68015 and GSE94349, were downloaded from the Gene Expression Omnibus (GEO) database. The differentially expressed genes (DEGs) were identified by the Limma package, and 271 differentially expressed immune-related genes (DEIRGs) were obtained from the Immport database. The gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Enrichment Analysis (GSEA) were performed for annotation, visualization, and integrated discovery. Five hub genes, including CXCL6, CXCL10, CXCL11, CXCL13, and SAA1, were screened out through protein-protein interaction (PPI) network interaction construction. Two diagnostic markers, namely S100A2 and SDC1 (both of which have the Area Under Curve value of 1), were screened by the machine learning algorithm. CIBERSORT analysis showed that M2 macrophages, activated NK cells, and gamma delta T cells had higher abundance in ACP infiltration, while CD8+ T cells, regulatory T cells, and Neutrophils had less abundance in ACP infiltration. The expression of gamma delta T cells was positively correlated with CXCL6, S100A2, SDC1, and SAA1, while CD8+ T cells expression was negatively correlated with CXCL6, S100A2, SDC1, and CXCL10. ACP with high CXCL6 showed remarkable drug sensitivity to Pentostatin and Wortmannin via CellMiner database analysis. Our results deepened the understanding of the molecular immune mechanism in ACP and provided potential biomarkers for the precisely targeted therapy for ACP.

The Construction and Comprehensive Analysis of a ceRNA Immunoregulatory Network and Tissue-Infiltrating Immune Cells in Atrial Fibrillation

Background

At present, the mechanisms behind atrial fibrillation (AF) pathogenesis are still unclear. We construct a ceRNA immunoregulatory network to further understand the mechanism of AF.

Methods

Four AF mRNA datasets from the Gene Expression Omnibus (GEO) database were integrated by SVA method. AF-related immune genes (AF-IRGs) were selected via combining ImmPort database with the genes in the module most associated with AF obtained by a weighted gene coexpression network analysis (WGCNA). Then, circRNA and miRNA expressions from the GEO database were extracted and mapped with related databases. Next, an immune-related circRNA-miRNA-mRNA ceRNA network was constructed and hub genes were filtered from a protein–protein interaction (PPI) network, and the differentially expressed (DE) hub genes in AF were further screened. Additionally, immune infiltration was investigated in AF by using CIBERSORT. Subsequently, the relationships between DE hub genes and AF-related infiltrating immune cells were performed by using Pearson correlation coefficients. Ulteriorly, the immune-cells-related ceRNA subnetwork in AF was built.

Results

A total of 95 AF-IRGs were detected, and an immune-related ceRNA network in AF was constructed with 12 circRNAs, 7 miRNAs and 50 mRNAs. The immune infiltration analysis indicated that a higher level of neutrophils, as well as a lower level of T cells regulatory (Tregs) and NK cells activated in AF. Four DE hub genes (CXCL12, IL7R, TNFSF13B, CD8A) were associated with Tregs or NK cells activated immune cells (P < 0.05). Tregs or NK cells activated immune cells-related ceRNA subnetwork including 5 circRNAs (has_circ_0001190, has_circ_0006725, has_circ_0079284, has_circ_0005299, and has_circ_0002103), 4 miRNAs (has-miR-198, has-miR-623, has-miR-1246, and has-miR-339-3p) and 4 DE hub genes was eventually constructed in AF.

Conclusion

Our results provide new insights into the molecular mechanisms governing AF progression from the perspective of immune-related ceRNA network.

Cxcl10 chemokine induces migration of ING4-deficient breast cancer cells via a novel crosstalk mechanism between the Cxcr3 and Egfr receptors

The chemokine Cxcl10 has been associated with poor prognosis in breast cancer, but the mechanism is not well understood. Our previous study have shown that CXCL10 was repressed by the ING4 tumor suppressor, suggesting a potential inverse functional relationship. We thus investigated a role for Cxcl10 in the context of ING4 deficiencies in breast cancer. We first analyzed public gene expression datasets and found that patients with CXCL10-high/ING4-low expressing tumors had significantly reduced disease-free survival in breast cancer. In vitro, Cxcl10 induced migration of ING4-deleted breast cancer cells, but not of ING4-intact cells. Using inhibitors, we found that Cxcl10-induced migration of ING4-deleted cells required Cxcr3, Egfr, and the Gβγ subunits downstream of Cxcr3, but not Gαi. Immunofluorescent imaging showed that Cxcl10 induced early transient colocalization between Cxcr3 and Egfr in both ING4-intact and ING4-deleted cells, which recurred only in ING4-deleted cells. A peptide agent that binds to the internal juxtamembrane domain of Egfr inhibited Cxcr3/Egfr colocalization and cell migration. Taken together, these results presented a novel mechanism of Cxcl10 that elicits migration of ING4-deleted cells, in part by inducing a physical or proximal association between Cxcr3 and Egfr and signaling downstream via Gβγ. These results further indicated that ING4 plays a critical role in the regulation of Cxcl10 signaling that enables breast cancer progression.

Contribution of CXCR3-mediated signaling in the metastatic cascade of solid malignancies

Metastasis is a significant cause of the mortality resulting from solid malignancies. The process of metastasis is complex and is regulated by numerous cancer cell-intrinsic and -extrinsic factors. CXCR3 is a chemokine receptor that is frequently expressed by cancer cells, endothelial cells and immune cells. CXCR3A signaling in cancer cells tends to promote the invasive and migratory phenotype of cancer cells. Indirectly, CXCR3 modulates the anti-tumor immune response resulting in variable effects that can permit or inhibit metastatic progression. Finally, the activity of CXCR3B in endothelial cells is generally angiostatic, which limits the access of cancer cells to key conduits to secondary sites. However, the interaction of these activities within a tumor and the presence of opposing CXCR3 splice variants clouds the picture of the role of CXCR3 in metastasis. Consequently, thorough analysis of the contributions of CXCR3 to cancer metastasis is necessary. This review is an in-depth examination of the involvement of CXCR3 in the metastatic process of solid malignancies.

Wrinkle in the plan: miR-34a-5p impacts chemokine signaling by modulating CXCL10/CXCL11/CXCR3-axis in CD4+, CD8+ T cells, and M1 macrophages

BACKGROUND

In 2016 the first-in-human phase I study of a miRNA-based cancer therapy with a liposomal mimic of microRNA-34a-5p (miR-34a-5p) was closed due to five immune related serious adverse events (SAEs) resulting in four patient deaths. For future applications of miRNA mimics in cancer therapy it is mandatory to unravel the miRNA effects both on the tumor tissue and on immune cells. Here, we set out to analyze the impact of miR-34a-5p over-expression on the CXCL10/CXCL11/CXCR3 axis, which is central for the development of an effective cancer control.

METHODS

We performed a whole genome expression analysis of miR-34a-5p transfected M1 macrophages followed by an over-representation and a protein-protein network analysis. In-silico miRNA target prediction and dual luciferase assays were used for target identification and verification. Target genes involved in chemokine signaling were functionally analyzed in M1 macrophages, CD4⁺ and CD8⁺ T cells.

RESULTS

A whole genome expression analysis of M1 macrophages with induced miR-34a-5p over-expression revealed an interaction network of downregulated target mRNAs including CXCL10 and CXCL11. In-silico target prediction in combination with dual luciferase assays identified direct binding of miR-34a-5p to the 3'UTRs of CXCL10 and CXCL11. Decreased CXCL10 and CXCL11 secretion was shown on the endogenous protein level and in the supernatant of miR-34a-5p transfected and activated M1 macrophages. To complete the analysis of the CXCL10/CXCL11/CXCR3 axis, we activated miR-34a-5p transfected CD4⁺ and CD8⁺ T cells by PMA/Ionomycin and found reduced levels of endogenous CXCR3 and CXCR3 on the cell surface.

CONCLUSIONS

MiR-34a-5p mimic administered by intravenous administration will likely not only be up-taken by the tumor cells but also by the immune cells. Our results indicate that miR-34a-5p over-expression leads in M1 macrophages to a reduced secretion of CXCL10 and CXCL11 chemokines and in CD4⁺ and CD8⁺ T cells to a reduced expression of CXCR3. As a result, less immune cells will be attracted to the tumor site. Furthermore, high levels of miR-34a-5p in naive CD4⁺ T cells can in turn hinder Th1 cell polarization through the downregulation of CXCR3 leading to a less pronounced activation of cytotoxic T lymphocytes, natural killer, and natural killer T cells and possibly contributing to lymphocytopenia.

Chemokine Receptor Antagonists: Role in Oncology

PURPOSE OF REVIEW

To evaluate the clinical potential of chemokine receptor antagonists for the treatment of patients with cancer.

RECENT FINDINGS

Chemokine receptors and their ligands can have a significant impact on the infiltration of cells into the tumor microenvironment. The receptors are increasingly being investigated as targets for the treatment of cancers. Recent studies are demonstrating the promise of chemokine receptor antagonists in this setting. There are many chemokine receptors, and each can have different functions depending on the cellular context. Targeting chemokine receptors is a promising strategy in both pre-clinical research and clinical trials. Inhibiting chemokine receptors that either recruit suppressive cells or improve cancer mobility and viability while sparing those necessary for proper immune trafficking may prove to dramatically improve treatment responses. Further research in this area is warranted and has the potential to dramatically improve patient outcomes.

The Role of Post-Translational Modifications of Chemokines by CD26 in Cancer

Chemokines are a large family of small chemotactic cytokines that fulfill a central function in cancer. Both tumor-promoting and -impeding roles have been ascribed to chemokines, which they exert in a direct or indirect manner. An important post-translational modification that regulates chemokine activity is the NH₂-terminal truncation by peptidases. CD26 is a dipeptidyl peptidase (DPPIV), which typically clips a NH₂-terminal dipeptide from the chemokine. With a certain degree of selectivity in terms of chemokine substrate, CD26 only recognizes chemokines with a penultimate proline or alanine. Chemokines can be protected against CD26 recognition by specific amino acid residues within the chemokine structure, by oligomerization or by binding to cellular glycosaminoglycans (GAGs). Upon truncation, the binding affinity for receptors and GAGs is altered, which influences chemokine function. The consequences of CD26-mediated clipping vary, as unchanged, enhanced, and reduced activities are reported. In tumors, CD26 most likely has the most profound effect on CXCL12 and the interferon (IFN)-inducible CXCR3 ligands, which are converted into receptor antagonists upon truncation. Depending on the tumor type, expression of CD26 is upregulated or downregulated and often results in the preferential generation of the chemokine isoform most favorable for tumor progression. Considering the tight relationship between chemokine sequence and chemokine binding specificity, molecules with the appropriate characteristics can be chemically engineered to provide innovative therapeutic strategies in a cancer setting.

Establishment of an In Vivo Xenograft Mouse Model of a Subcutaneous Submillimeter HT-29 Tumor Formed from a Single Spheroid Transplanted Using Radiation-Crosslinked Gelatin Hydrogel Microwell

Colorectal cancer is a frequent cause of death worldwide. The detection and treatment of small nodules are crucial for improving survival of colorectal cancer patients. Submillimeter tumors are useful tools for developing novel methods to approach this issue. However, there are no suitable in vivo models that allow easy monitoring of the growth of these tumors. This study established a xenograft mouse model of subcutaneous submillimeter tumors with human colorectal cancer HT-29 cells. We transplanted a single spheroid formed by HT-29 cells expressing red fluorescent protein (RFP) (HT-29-RFP). Additionally, we adopted our newly developed radiation-crosslinked gelatin hydrogel microwells (rGHMs), which can be used as a culture base to form spheroids and as a transplantation scaffold with biocompatibility and biodegradability. Spheroids approximately 700 μm in size were uniformly created in seven days in the respective rGHMs. Every single spheroid was extracted either with or without rGHM and transplanted into the subcutis of severe combined immunodeficiency (SCID) mice (n = 4). After 21 days, the spheroids inoculated together with rGHM successfully formed uniform subcutaneous submillimeter tumor xenografts that were observable in vivo in a stereoscopic fluorescence microscope in all transplanted mice. In contrast, spheroids transplanted without rGHM also developed small tumors in all mice but showed higher variability in size than those transplanted with rGHM. During transplantation, the rGHM ensured easy handling and stabilization of the position of a single spheroid. Inoculation of spheroids with rGHM in the nude mice was similarly examined (n = 4), showing that only one out of four mice formed tumors. In conclusion, rGHM effectively formed spheroids and created uniformed xenografted submillimeter tumors of HT-29-RFP in SCID mice. Our model could provide a useful platform to develop medicines and methods for detection and treatment of small nodules of colorectal cancer.

Imbalance of Chemokines and Cytokines in the Bone Marrow Microenvironment of Children with B-Cell Acute Lymphoblastic Leukemia

In the hematopoietic microenvironment, leukemic cells secrete factors that imbalanced chemokine and cytokine production. However, the network of soluble immunological molecules in the bone marrow microenvironment of acute lymphoblastic leukemia (ALL) remains underexplored. Herein, we evaluated the levels of the immunological molecules (CXCL8, CCL2, CXCL9, CCL5, CXCL10, IL-6, TNF, IFN-γ, IL-17A, IL-4, IL-10, and IL-2) in the bone marrow plasma of 47 recently diagnosed B-cell acute lymphoblastic leukemia (B-ALL) patients during induction therapy using cytometric beads arrays. The results demonstrated that B-ALL patients showed high levels of CXCL9, CXCL10, IL-6, and IL-10 at the time of diagnosis, while at the end of induction therapy, a decrease in the levels of these immunological molecules and an increase in CCL5, IFN-γ, and IL-17A levels were observed. These findings indicate that B-ALL patients have an imbalance in chemokines and cytokines in the bone marrow microenvironment that contributes to suppressing the immune response. This immune imbalance may be associated with the presence of leukemic cells since, at the end of the induction therapy, with the elimination and reduction to residual cells, the proinflammatory profile is reestablished, characterized by an increase in the cytokines of the Th1 and Th17 profiles.

TNF-α augments CXCL10/CXCR3 axis activity to induce Epithelial-Mesenchymal Transition in colon cancer cell

Chronic inflammation-induced metastases have long been regarded as one of the significant obstacles in treating cancer. Tumor necrosis factor-α (TNF-α), a main inflammation mediator within tumor microenvironment, affects tumor development by inducing multiple chemokines to establish a complex network. Recent reports have revealed that CXCL10/CXCR3 axis affects cancer cells invasiveness and metastases, and Epithelial-mesenchymal transition (EMT) is the main reason for frequent proliferation and distant organ metastases of colon cancer (CC) cells, However, it is unclear whether TNF-α- mediated chronic inflammation can synergically enhance EMT-mediated CC metastasis through promoting chemokine expression. According to this study, TNF-α activated the PI3K/Akt and p38 MAPK parallel signal transduction pathways, then stimulate downstream NF-κB pathway p65 into the nucleus to activate CXCL10 transcription. CXCL10 enhanced the metastases of CC-cells by triggering small GTPases such as RhoA and cdc42. Furthermore, overexpression of CXCL10 significantly enhanced tumorigenicity and mobility of CC cells in vivo. We further clarified that CXCL10 activated the PI3K/Akt pathway through CXCR3, resulting in suppression of GSK-3β phosphorylation and leading to upregulation of Snail expression, thereby regulating EMT in CC cells. These outcomes lay the foundation for finding new targets to inhibit CC metastases.

Systemic tumour suppression via the preferential accumulation of erythrocyte-anchored chemokine-encapsulating nanoparticles in lung metastases

Eliciting immune responses against primary tumours is hampered by their immunosuppressive microenvironment and by the greater inaccessibility of deeper intratumoural cells. However, metastatic tumour cells are exposed to highly perfused and immunoactive organs, such as the lungs. Here, by taking advantage of the preferential colocalization of intravenously administered erythrocytes with metastases in the lungs, we show that treatment with chemokine-encapsulating nanoparticles that are non-covalently anchored onto the surface of injected erythrocytes results in local and systemic tumour suppression in mouse models of lung metastasis. Such erythrocyte-anchored systemic immunotherapy led to the infiltration of effector immune cells into the lungs, in situ immunization without the need for exogenous antigens, inhibition of the progression of lung metastasis, and significantly extended animal survival and systemic immunity that suppressed the growth of distant tumours after rechallenge. Erythrocyte-mediated systemic immunotherapy may represent a general and potent strategy for cancer vaccination.

Interferon regulatory factor 1(IRF-1) activates anti-tumor immunity via CXCL10/CXCR3 axis in hepatocellular carcinoma (HCC)

Interferon regulatory factor 1 (IRF-1) is a tumor suppressor gene in cancer biology with anti-proliferative and pro-apoptotic effect on cancer cells, however mechanisms of IRF-1 regulating tumor microenvironment (TME) in hepatocellular carcinoma (HCC) remain only partially characterized. Here, we investigated that IRF-1 regulates C-X-C motif chemokine 10 (CXCL10) and chemokine receptor 3 (CXCR3) to activate anti-tumor immunity in HCC. We found that IRF-1 mRNA expression was positively correlated with CXCL10 and CXCR3 through qRT-PCR assay in HCC tumors and in analysis of the TCGA database. IRF-1 response elements were identified in the CXCL10 promoter region, and ChIP-qPCR confirmed IRF-1 binding to promote CXCL10 transcription. IRF-2 is a competitive antagonist for IRF-1 mediated transcriptional effects, and overexpression of IRF-2 decreased basal and IFN-γ induced CXCL10 expression. Although IRF-1 upregulated CXCR3 expression in HCC cells, it inhibited proliferation and exerted pro-apoptotic effects, which overcome proliferation partly mediated by activating the CXCL10/CXCR3 autocrine axis. In vitro and in vivo studies showed that IRF-1 increased CD8⁺ T cells, NK and NKT cells migration, and activated IFN-γ secretion in NK and NKT cells to induce tumor apoptosis through the CXCL10/CXCR3 paracrine axis. Conversely, this effect was markedly abrogated in HCC tumor bearing mice deficient in CXCR3. Therefore, the IRF-1/CXCL10/CXCR3 axis contributes to the anti-tumor microenvironment in HCC.

Identification of prognosis-related genes in the cervical cancer immune microenvironment

BACKGROUND

Cervical cancer is the fourth most commonly diagnosed cancer in women worldwide. The metastasis and invasion of this type of cancer are closely related to the tumor microenvironment. Immune cells and stromal cells dominate the tumor microenvironment in cervical cancer. Therefore, we should further investigate the complex interplay between the tumor progression with immune cells or stromal cells.

METHODS

We downloaded the gene expression profiles and clinical data of 307 patients with cervical cancers based on the TCGA database. Subsequently, the Estimation of Stromal and Immune cells in Malignant Tumours using Expression data (ESTIMATE) algorithm was used to calculate the scores of stromal cells and immune cells in order to uncover differential expressed genes, and we analyzed the correlation between their scores and patient survival. Then the Cell type Identification By Estimating Relative Subsets Of known RNA Transcripts (CIBERSORT) deconvolution algorithm was applied to quantify the fraction and infiltration of 22 types of immune cells in cervical cancer. Moreover, we also used R language packs and network tools to analyze GO term, gene enrichment pathway, and protein-protein relationship to trace down genes related to inflammation and immune regulation.

RESULTS

The gene expression profiles and corresponding clinical data of 307 patients were obtained from TCGA database. The results showed that the scores were statistically significant between the high immunescore group and the low immunescore group. And the low immunescore group had shorter survival period than the high scores group (P = 0.035). Among the 22 types of immune cells, only T cells and mast cells were significantly related to the survival rate of cervical cancer patients. Moreover, PPI network analysis revealed that CCR5 and CXCL9, -10, -11/CXCR3 axis might be a new target for cervical cancer treatment. Finally, Kaplan-Meier survival curves found outnine representative genes significantly related to survival rate including BTNL8, CCR7, CD1E, CD6, CD27, CD79A, GRAP2, SP1B, LY9.

CONCLUSIONS

These genes can be used as markers for the prognosis and diagnosis of cervical cancer and also might be used as treatment targets.

CXCL11 Signaling in the Tumor Microenvironment

CXCL11 which can bind to two different chemokine receptors, CXCR3 and CXCR7, has found a prominent place in current tumor research. In this chapter, we mainly discuss the current evidence on the role of the immune response of CXCL11 in tumor microenvironment (TME). The diverse functions of CXCL11 include inhibiting angiogenesis, affecting the proliferation of different cell types, playing a role in fibroblast directed carcinoma invasion, increasing adhesion properties, suppressing M2 macrophage polarization, and facilitating the migration of certain immune cells. In addition, we discussed the application of CXCL11 as an adjuvant to various mainstream anti-cancer therapies and the future challenges in the application of CXCL11 targeted therapies.

CXCL9 Is a Potential Biomarker of Immune Infiltration Associated With Favorable Prognosis in ER-Negative Breast Cancer

The chemokine CXCL9 (C-X-C motif chemokine ligand 9) has been reported to be required for antitumour immune responses following immune checkpoint blockade. In this study, we sought to investigate the potential value of CXCL9 according to immune responses in patients with breast cancer (BC). A variety of open-source databases and online tools were used to explore the expression features and prognostic significance of CXCL9 in BC and its correlation with immune-related biomarkers followed by subsequent verification with immunohistochemistry experiments. The CXCL9 mRNA level was found to be significantly higher in BC than in normal tissue and was associated with better survival outcomes in patients with ER-negative tumours. Moreover, CXCL9 is significantly correlated with immune cell infiltration and immune-related biomarkers, including CTLA4, GZMB, LAG3, PDCD1 and HAVCR2. Finally, we performed immunohistochemistry with breast cancer tissue samples and observed that CXCL9 is highly expressed in the ER-negative subgroup and positively correlated with the immune-related factors LAG3, PD1, PDL1 and CTLA4 to varying degrees. These findings suggest that CXCL9 is an underlying biomarker for predicting the status of immune infiltration in ER-negative breast cancer.

Tumor inhibition or tumor promotion? The duplicity of CXCR3 in cancer

Tumor tissue includes cancer cells and normal stromal cells such as vascular endothelial cells, connective tissue cells (cancer associated fibroblast, mesenchymal stem cell), and immune cells (tumor-infiltrating lymphocytes or TIL, dendritic cells, eosinophils, basophils, mast cells, tumor-associated macrophages or TAM, myeloid-derived suppressor cells or MDSC). Anti-tumor activity is mainly mediated by infiltration of NK cells, Th1 and CD8⁺ T cells, and correlates with expression of NK cell and T cell attracting chemokines. Nevertheless, cancer cells hijack tissue homeostasis through secretion of cytokines and chemokines that mediate not only the induction of an inflamed status that supports cancer cell survival and growth, but also the recruitment and/or activation of immune suppressive cells. CXCL9, CXCL10, and CXCL11 are known for their tumor-inhibiting properties, but their overexpression in several hematologic and solid tumors correlates with disease severity, suggesting a role in tumor promotion. The dichotomous nature of CXCR3 ligands activity mainly depends on several molecular mechanisms induced by cancer cells themselves able to divert immune responses and to alter the whole local environment. A deep understanding of the nature of such phenomenon may provide a rationale to build up a CXCR3/ligand axis targeting strategy. In this review, we will discuss the role of CXCR3 in cancer progression and in regulation of anti-tumor immune response and immunotherapy.

Expression and role of MIG/CXCR3 axis in mantle cell lymphoma

Mantle cell lymphoma (MCL) is a unique subtype of B-cell non-Hodgkin lymphoma with a generally aggressive and heterogeneous clinical course. Chemokines are one of the complex components in the tumor microenvironment (TME), and they play a vital role in tumor progression and metastasis. There is no information about the monokine induced by gamma interferon (MIG)/CXC chemokine receptor 3 (CXCR3) axis in patients with MCL. In the present study, we discovered that CXCR3 was highly expressed in MCL tissues and some cell lines including Maver, Z138, and Jeko-1, and significantly associated with clinical factors reflecting high tumor burden in MCL patients. Moreover, elevated serum MIG at diagnosis showed a close relationship with advanced disease and poor prognosis in MCL patients. Additionally, the role of CXCR3 in promoting the proliferation and inhibiting the apoptosis of primary MCL cells and Jeko-1 cells was validated by in vitro experiments. Further research indicated that the MIG/CXCR3 axis mediated MCL cell migration to the TME through the PI3K/AKT signaling pathway. Therefore, the MIG/CXCR3 axis might be a potential target with fewer off-target side effects than other targets in MCL.

CXC Chemokine/Receptor Axis Profile and Metastasis in Prostate Cancer

In this study, the effects of the CXC chemokine/receptor axis on lymph node and distant metastases of prostate cancer (PC) were analyzed. Further, mRNA expression data of metastatic PC were extracted from the Stand Up To Cancer–Prostate Cancer Foundation Dream Team database and differences between metastatic sites were comprehensively analyzed. CXC chemokine/receptor mRNA expression data of primary PC included in the Cancer Genome Atlas were used to analyze the relationships of CXC chemokine/receptor expression with lymph node metastasis and cancer progression. In metastatic PC, significantly higher expression of ELR⁺ CXC chemokines/receptors and significantly lower expression of ELR⁻ CXC chemokines/receptors were observed in bone metastases relative to lymph node metastases. In primary PC, significantly higher ELR⁻ CXC chemokine/receptor expression and significantly lower ELR⁺ CXC chemokine/receptor expression were observed in patients with lymph node metastasis relative to those without. Multivariate logistic regression analysis identified CXCL10 expression as an independent predictor of lymph node metastasis. Furthermore, the log-rank test results revealed that co-expression of CXCL10/CXCR3 was associated with postoperative recurrence. These findings demonstrate heterogeneous expression of CXC chemokine/receptor genes in primary PC as well as differences in expression patterns according to the metastatic site.

Integrated analysis of tumor mutation burden and immune infiltrates in endometrial cancer

To explore the prognostic value of tumor mutation burden (TMB) and its correlation with immune infiltrates in endometrial cancer. Transcriptome and somatic mutation profiles of Uterine Corpus Endometrial Carcinoma (UCEC) were downloaded from TCGA database. Somatic mutations were analyzed by "maftools" and visualized in waterfall plot. We calculated TMB of each patients and divided all patients into the high-TMB group and the low-TMB group by the median threshold. Survival analysis and Wilcoxon test were used to investigate the prognostic value of TMB and its association with clinical variables. Differentially expressed genes (DEGs) were identified in 2 TMN groups and functional analysis was performed to find out significant biological pathways. A TMB-related signature was conducted by multivariate analysis, receiver operating characteristic (ROC) curve was performed to predict accuracy of the model, meanwhile, a validation cohort from Fudan University Shanghai Cancer Center (FUSCC) was obtained to verify the signature. Then we estimated association between TMB and immune infiltrates by CIBERSORT algorithm and figured out prognostic immune cells of UCEC in TIMER database. Total 575 samples including 25 normal tissues and 552 tumor samples were enrolled from TCGA database. PTEN mutations accounted for the most and single nucleotide polymorphism and C>T transitions were most frequent forms of somatic mutations in UCEC. The low-TMB group possessed worse survival than the high-TMB group (P = 0.004). DEGs in 2 TMB groups were mostly enriched in adaptive immune response and immunoglobulin/immune receptor component. A TMB-related signature consisting of GFAP, EDN3, CXCR3, PLXNA4, SST presented good predictability with area under the curve (AUC) = 0.686. In FUSCC validation cohort, the high-risk group possessed worse survival outcome than the low-risk group (P = 0.015). Immune infiltrates was correlated to survival in UCEC and low TMB were associated with less immune infiltrates, which suggested poor immune response. TMB was not only related to overall survival but also immune infiltrates in UCEC. The TMB-related signature (GFAP, EDN3, CXCR3, PLXNA4, SST) had good predictability for overall survival in endometrial cancer. Our study might have some merits in elucidating potential mechanism of TMB and immune infiltrates in UCEC and providing guidance of immunotherapy for endometrial cancer.

The role of PKC in CXCL8 and CXCL10 directed prostate, breast and leukemic cancer cell migration

Migration of tumour cells is a fundamental process for the formation and progression of metastasis in malignant diseases. Chemokines binding to their cognate receptors induce the migration of cancer cells, however, the molecular signalling pathways involved in this process are not fully understood. Protein kinase C (PKC) has been shown to regulate cell migration, adhesion and proliferation. In order to identify a connection between PKC and tumour progression in breast, prostate and leukaemia cells, the effect of PKC on CXCL8 or CXCL10-mediated cell migration and morphology was analysed. We tested the speed of the migrating cells, morphology, and chemotaxis incubated with different PKC isoforms inhibitors- GF109203X, staurosporine and PKCζ pseudosubstrate inhibitor (PKCζi). We found that the migration of CXCL8-driven PC3 and MDA-MB231 cells in the presence of conventional, novel or atypical PKCs was not affected, but atypical PKCζ is crucial for THP-1 chemotaxis. The speed of CXCL10-activated PC3 and MDA-MB231 cells was significantly reduced in the presence of conventional, novel and atypical PKCζ. THP-1 chemotaxis was again affected by atypical PKCζi. On the other hand, cell area, circularity or aspect ratio were affected by staurosporine in CXCL8 or CXCL10-activated cells, demonstrating a role of PKCα in the rearrangement of the cytoskeleton regardless of the effect on the migration. Consequently, this allows the speculation that different PKC isoforms induce different outcomes in migration and actin cytoskeleton based on the chemokine receptor and/or the cell type.