CCR4 as a Therapeutic Target for Cancer Immunotherapy

CAR products from novel sources: a new avenue for the breakthrough in cancer immunotherapy

Chimeric antigen receptor (CAR) T cell therapy has transformed cancer immunotherapy. However, significant challenges limit its application beyond B cell-driven malignancies, including limited clinical efficacy, high toxicity, and complex autologous cell product manufacturing. Despite efforts to improve CAR T cell therapy outcomes, there is a growing interest in utilizing alternative immune cells to develop CAR cells. These immune cells offer several advantages, such as major histocompatibility complex (MHC)-independent function, tumor microenvironment (TME) modulation, and increased tissue infiltration capabilities. Currently, CAR products from various T cell subtypes, innate immune cells, hematopoietic progenitor cells, and even exosomes are being explored. These CAR products often show enhanced antitumor efficacy, diminished toxicity, and superior tumor penetration. With these benefits in mind, numerous clinical trials are underway to access the potential of these innovative CAR cells. This review aims to thoroughly examine the advantages, challenges, and existing insights on these new CAR products in cancer treatment.

ITGAM-macrophage modulation as a potential strategy for treating neutrophilic Asthma: insights from bioinformatics analysis and in vivo experiments

Identification of molecular biomarkers associated with neutrophilic asthma (NA) phenotype may inform the discovery of novel pathobiological mechanisms and the development of diagnostic markers. Three mRNA transcriptome datasets extracted from induced sputum of asthma patients with various inflammatory types were used to screen for macrophage-related molecular mechanisms and targets in NA. Furthermore, the predicted targets were also validated on an independent dataset (N = 3) and animal model (N = 5). A significant increase in total cells, neutrophils and macrophages was observed in bronchoalveolar lavage (BAL) fluid of NA mice induced by ovalbumin/freund's adjuvant, complete (OVA/CFA). And we also found elevated levels of neutrophil and macrophage infiltration in NA subtype in external datasets. NA mice had increased secretion of IgE, IL-1β, TNF-α and IL-6 in serum and BAL fluid. MPO, an enzyme present in neutrophils, was also highly expressed in NA mice. Then, weighted gene co-expression network analysis (WGCNA) identified 684 targets with the strongest correlation with NA, and we obtained 609 macrophage-related specific differentially expressed genes (DEGs) in NA by integrating macrophage-related genes. The top 10 genes with high degree values were obtained and their mRNA levels and diagnostic performance were then determined by RT-qPCR and receiver operator characteristic (ROC) analysis. Statistically significant correlations were found between macrophages and all key targets, with the strongest correlation between ITGAM and macrophages in NA. Double-Immunofluorescence staining further confirmed the co-localization of ITGAM and F4/80 in NA. ITGAM was identified as a critical target to distinguish NA from healthy/non-NA individuals, which may provide a novel avenue to further uncover the mechanisms and therapy of NA.

CC Chemokine Family Members' Modulation as a Novel Approach for Treating Central Nervous System and Peripheral Nervous System Injury-A Review of Clinical and Experimental Findings

Despite significant progress in modern medicine and pharmacology, damage to the nervous system with various etiologies still poses a challenge to doctors and scientists. Injuries lead to neuroimmunological changes in the central nervous system (CNS), which may result in both secondary damage and the development of tactile and thermal hypersensitivity. In our review, based on the analysis of many experimental and clinical studies, we indicate that the mechanisms occurring both at the level of the brain after direct damage and at the level of the spinal cord after peripheral nerve damage have a common immunological basis. This suggests that there are opportunities for similar pharmacological therapeutic interventions in the damage of various etiologies. Experimental data indicate that after CNS/PNS damage, the levels of 16 among the 28 CC-family chemokines, i.e., CCL1, CCL2, CCL3, CCL4, CCL5, CCL6, CCL7, CCL8, CCL9, CCL11, CCL12, CCL17, CCL19, CCL20, CCL21, and CCL22, increase in the brain and/or spinal cord and have strong proinflammatory and/or pronociceptive effects. According to the available literature data, further investigation is still needed for understanding the role of the remaining chemokines, especially six of them which were found in humans but not in mice/rats, i.e., CCL13, CCL14, CCL15, CCL16, CCL18, and CCL23. Over the past several years, the results of studies in which available pharmacological tools were used indicated that blocking individual receptors, e.g., CCR1 (J113863 and BX513), CCR2 (RS504393, CCX872, INCB3344, and AZ889), CCR3 (SB328437), CCR4 (C021 and AZD-2098), and CCR5 (maraviroc, AZD-5672, and TAK-220), has beneficial effects after damage to both the CNS and PNS. Recently, experimental data have proved that blockades exerted by double antagonists CCR1/3 (UCB 35625) and CCR2/5 (cenicriviroc) have very good anti-inflammatory and antinociceptive effects. In addition, both single (J113863, RS504393, SB328437, C021, and maraviroc) and dual (cenicriviroc) chemokine receptor antagonists enhanced the analgesic effect of opioid drugs. This review will display the evidence that a multidirectional strategy based on the modulation of neuronal-glial-immune interactions can significantly improve the health of patients after CNS and PNS damage by changing the activity of chemokines belonging to the CC family. Moreover, in the case of pain, the combined administration of such antagonists with opioid drugs could reduce therapeutic doses and minimize the risk of complications.

Reprogramming of pyrimidine nucleotide metabolism supports vigorous cell proliferation of normal and malignant T cells

ABSTRACT

Adult T-cell leukemia/lymphoma (ATL) is triggered by infection with human T-cell lymphotropic virus-1 (HTLV-1). Here, we describe the reprogramming of pyrimidine biosynthesis in both normal T cells and ATL cells through regulation of uridine-cytidine kinase 2 (UCK2), which supports vigorous proliferation. UCK2 catalyzes the monophosphorylation of cytidine/uridine and their analogues during pyrimidine biosynthesis and drug metabolism. We found that UCK2 was overexpressed aberrantly in HTLV-1-infected T cells but not in normal T cells. T-cell activation via T-cell receptor (TCR) signaling induced expression of UCK2 in normal T cells. Somatic alterations and epigenetic modifications in ATL cells activate TCR signaling. Therefore, we believe that expression of UCK2 in HTLV-1-infected cells is induced by dysregulated TCR signaling. Recently, we established azacitidine-resistant (AZA-R) cells showing absent expression of UCK2. AZA-R cells proliferated normally in vitro, whereas UCK2 knockdown inhibited ATL cell growth. Although uridine and cytidine accumulated in AZA-R cells, possibly because of dysfunction of pyrimidine salvage biosynthesis induced by loss of UCK2 expression, the amount of UTP and CTP was almost the same as in parental cells. Furthermore, AZA-R cells were more susceptible to an inhibitor of dihydroorotic acid dehydrogenase, which performs the rate-limiting enzyme of de novo pyrimidine nucleotide biosynthesis, and more resistant to dipyridamole, an inhibitor of pyrimidine salvage biosynthesis, suggesting that AZA-R cells adapt to UCK2 loss by increasing de novo pyrimidine nucleotide biosynthesis. Taken together, the data suggest that fine-tuning pyrimidine biosynthesis supports vigorous cell proliferation of both normal T cells and ATL cells.

CKLF instigates a "cold" microenvironment to promote MYCN-mediated tumor aggressiveness

Solid tumors, especially those with aberrant MYCN activation, often harbor an immunosuppressive microenvironment to fuel malignant growth and trigger treatment resistance. Despite this knowledge, there are no effective strategies to tackle this problem. We found that chemokine-like factor (CKLF) is highly expressed by various solid tumor cells and transcriptionally up-regulated by MYCN. Using the MYCN-driven high-risk neuroblastoma as a model system, we demonstrated that as early as the premalignant stage, tumor cells secrete CKLF to attract CCR4-expressing CD4+ cells, inducing immunosuppression and tumor aggression. Genetic depletion of CD4+ T regulatory cells abolishes the immunorestrictive and protumorigenic effects of CKLF. Our work supports that disrupting CKLF-mediated cross-talk between tumor and CD4+ suppressor cells represents a promising immunotherapeutic approach to battling MYCN-driven tumors.

Adult T-cell Leukemia/Lymphoma (ATL) in the Nasal and Paranasal Cavity: Four Cases Report

Adult T-cell leukemia/lymphoma (ATL) is a form of leukemia caused by the human T-cell leukemia virus type I (HTLV-1). Otolaryngologists often diagnose ATL based on cervical lymphadenopathy or Waldeyer ring lesions. However, there are few reports of ATL occurring in the nasal and paranasal cavity. Here, we report four such cases of ATL. Case 1: An 82-year-old man diagnosed with acute-type ATL with a tumor in the nasal cavity underwent 5 courses of THP-COP, but died after 36 months due to ATL. Case 2: A 62-year-old woman diagnosed with lymphoma-type ATL with a tumor in the frontal sinus was treated with 5 courses of VCAP-AMP-VECP, and has survived for more than 10 years. Case 3: A 64-year-old man diagnosed with lymphoma-type ATL with a tumor in the maxillary sinus underwent 8 courses of VCAP-AMP-VECP and 2 courses of mogamulizumab, but died after 34 months due to ATL. Case 4: A 52-year-old woman diagnosed with lymphoma-type ATL with tumors in both ethmoid sinuses received 2 courses of CHOP, 2 courses of DeVIC, radiotherapy (32 Gy) and 2 courses of mogamulizumab, but died after 9 months due to ATL.

Targeting T regulatory (Treg) cells in immunotherapy-resistant cancers

Primary or secondary (i.e., acquired) resistance is a common occurrence in cancer patients and is often associated with high numbers of T regulatory (Treg) cells (CD4+CD25+FOXP3+). The approval of ipilimumab and the development of similar pharmacological agents targeting cell surface proteins on Treg cells demonstrates that such intervention may overcome resistance in cancer patients. Hence, the clinical development and subsequent approval of Cytotoxic T Lymphocyte Antigen-4 (CTLA-4) targeting agents can serve as a prototype for similar agents. Such new agents aspire to be highly specific and have a reduced toxicity profile while increasing effector T cell function or effector T/T regulatory (Teff/Treg) ratio. While clinical development with large molecules has shown the greatest advancement, small molecule inhibitors that target immunomodulation are increasingly entering early clinical investigation. These new small molecule inhibitors often target specific intracellular signaling pathways [e.g., phosphoinositide-3-kinase delta (PI3K-δ)] that play an important role in regulating the function of Treg cells. This review will summarize the lessons currently applied to develop novel clinical agents that target Treg cells.

Downstream STING pathways IRF3 and NF-κB differentially regulate CCL22 in response to cytosolic dsDNA

Double-stranded DNA (dsDNA) in the cytoplasm of eukaryotic cells is abnormal and typically indicates the presence of pathogens or mislocalized self-DNA. Multiple sensors detect cytosolic dsDNA and trigger robust immune responses via activation of type I interferons. Several cancer immunotherapy treatments also activate cytosolic nucleic acid sensing pathways, including oncolytic viruses, nucleic acid-based cancer vaccines, and pharmacological agonists. We report here that cytosolic dsDNA introduced into malignant cells can robustly upregulate expression of CCL22, a chemokine responsible for the recruitment of regulatory T cells (Tregs). Tregs in the tumor microenvironment are thought to repress anti-tumor immune responses and contribute to tumor immune evasion. Surprisingly, we found that CCL22 upregulation by dsDNA was mediated primarily by interferon regulatory factor 3 (IRF3), a key transcription factor that activates type I interferons. This finding was unexpected given previous reports that type I interferon alpha (IFN-α) inhibits CCL22 and that IRF3 is associated with strong anti-tumor immune responses, not Treg recruitment. We also found that CCL22 upregulation by dsDNA occurred concurrently with type I interferon beta (IFN-β) upregulation. IRF3 is one of two transcription factors downstream of the STimulator of INterferon Genes (STING), a hub adaptor protein through which multiple dsDNA sensors transmit their signals. The other transcription factor downstream of STING, NF-κB, has been reported to regulate CCL22 expression in other contexts, and NF-κB has also been associated with multiple pro-tumor functions, including Treg recruitment. However, we found that NF-κB in the context of activation by cytosolic dsDNA contributed minimally to CCL22 upregulation compared with IRF3. Lastly, we observed that two strains of the same cell line differed profoundly in their capacity to upregulate CCL22 and IFN-β in response to dsDNA, despite apparent STING activation in both cell lines. This finding suggests that during tumor evolution, cells can acquire, or lose, the ability to upregulate CCL22. This study adds to our understanding of factors that may modulate immune activation in response to cytosolic DNA and has implications for immunotherapy strategies that activate DNA sensing pathways in cancer cells.

Small Extracellular Vesicles Derived from Altered Peptide Ligand-Loaded Dendritic Cell Act as A Therapeutic Vaccine for Spinal Cord Injury Through Eliciting CD4+ T cell-Mediated Neuroprotective Immunity

The balance among different CD4+ T cell subsets is crucial for repairing the injured spinal cord. Dendritic cell (DC)-derived small extracellular vesicles (DsEVs) effectively activate T-cell immunity. Altered peptide ligands (APLs), derived from myelin basic protein (MBP), have been shown to affect CD4+ T cell subsets and reduce neuroinflammation levels. However, the application of APLs is challenging because of their poor stability and associated side effects. Herein, it is demonstrate that DsEVs can act as carriers for APL MBP87-99 A91 (A91-DsEVs) to induce the activation of 2 helper T (Th2) and regulatory T (Treg) cells for spinal cord injury (SCI) in mice. These stimulated CD4+ T cells can efficiently "home" to the lesion area and establish a beneficial microenvironment through inducing the activation of M2 macrophages/microglia, inhibiting the expression of inflammatory cytokines, and increasing the release of neurotrophic factors. The microenvironment mediated by A91-DsEVs may enhance axon regrowth, protect neurons, and promote remyelination, which may support the recovery of motor function in the SCI model mice. In conclusion, using A91-DsEVs as a therapeutic vaccine may help induce neuroprotective immunity in the treatment of SCI.

Structure, function and drug discovery of GPCR signaling

G protein-coupled receptors (GPCRs) are versatile and vital proteins involved in a wide array of physiological processes and responses, such as sensory perception (e.g., vision, taste, and smell), immune response, hormone regulation, and neurotransmission. Their diverse and essential roles in the body make them a significant focus for pharmaceutical research and drug development. Currently, approximately 35% of marketed drugs directly target GPCRs, underscoring their prominence as therapeutic targets. Recent advances in structural biology have substantially deepened our understanding of GPCR activation mechanisms and interactions with G-protein and arrestin signaling pathways. This review offers an in-depth exploration of both traditional and recent methods in GPCR structure analysis. It presents structure-based insights into ligand recognition and receptor activation mechanisms and delves deeper into the mechanisms of canonical and noncanonical signaling pathways downstream of GPCRs. Furthermore, it highlights recent advancements in GPCR-related drug discovery and development. Particular emphasis is placed on GPCR selective drugs, allosteric and biased signaling, polyphamarcology, and antibody drugs. Our goal is to provide researchers with a thorough and updated understanding of GPCR structure determination, signaling pathway investigation, and drug development. This foundation aims to propel forward-thinking therapeutic approaches that target GPCRs, drawing upon the latest insights into GPCR ligand selectivity, activation, and biased signaling mechanisms.

Monocyte-related cytokines/chemokines in cerebral ischemic stroke

AIMS

Ischemic stroke is one of the leading causes of death worldwide and the most common cause of disability in Western countries. Multiple mechanisms contribute to the development and progression of ischemic stroke, and inflammation is one of the most important mechanisms.

DISCUSSION

Ischemia induces the release of adenosine triphosphate/reactive oxygen species, which activates immune cells to produce many proinflammatory cytokines that activate downstream inflammatory cascades to induce fatal immune responses. Research has confirmed that peripheral blood immune cells play a vital role in the immunological cascade after ischemic stroke. The role of monocytes has received much attention among numerous peripheral blood immune cells. Monocytes induce their effects by secreting cytokines or chemokines, including CCL2/CCR2, CCR4, CCR5, CD36, CX3CL1/CX3CR1, CXCL12(SDF-1), LFA-1/ICAM-1, Ly6C, MMP-2/9, NR4A1, P2X4R, P-selectin, CD40L, TLR2/4, and VCAM-1/VLA-4. Those factors play important roles in the process of monocyte recruitment, migration, and differentiation.

CONCLUSION

This review focuses on the function and mechanism of the cytokines secreted by monocytes in the process of ischemic stroke and provides novel targets for treating cerebral ischemic stroke.

Chemokines: Function and therapeutic potential in bone metastasis of lung cancer

Lung cancer is a rapidly progressing disease with a poor prognosis. Bone metastasis is commonly found in 40.6% of advanced-stage patients. The mortality rate of lung cancer patients with bone metastasis can be significantly decreased by implementing novel diagnostic techniques, improved staging and classification systems, precise surgical interventions, and advanced treatment modalities. However, it is important to note that there is currently a lack of radical procedures available for these patients due to the development of drug resistance. Consequently, palliative care approaches are commonly employed in clinical practice. Therefore, new understandings of the process of bone metastasis of lung cancer are critical for developing better treatment strategies to improve patient's clinical cure rate and quality of life. Chemokines are cell-secreted small signaling proteins in cancer occurrence, proliferation, invasion, and metastasis. In this study, we review the development of bone metastasis in lung cancer and discuss the mechanisms of specific chemokine families (CC, CXC, CX3C, and XC) in regulating the biological activities of tumors and promoting bone metastasis. We also highlight some preclinical studies and clinical trials on chemokines for lung cancer and bone metastasis.

Systematic Pan-Cancer Analysis Reveals X-C Motif Chemokine Receptor 1 as a Prognostic and Immunological Biomarker

Chemokines and their receptors play an important role in immune monitoring and immune defense during tumor growth and metastasis. However, their prognostic roles in pan-cancer have not been elucidated. In this work, we screened all chemokine receptors in pan-cancer and discovered X-C Motif Chemokine Receptor 1 (XCR1) as a reliable immunological and prognostic biomarker in pan-cancer using bioinformation. The TCGA database served as the foundation for the primary research database analysis in this work. XCR1 was downregulated in tumors. Patients with reduced XCR1 showed worse prognoses and a concomitant decrease in immune cell infiltration (DCs and CD8+ T cells). According to a gene enrichment study, XCR1 enhanced immune system performance by promoting T-cell infiltration through the C-X-C Motif Chemokine Ligand 9 (CXCL9)- C-X-C Motif Chemokine Receptor 3 (CXCR3) axis. In addition, XCR1 is mainly expressed in infiltrated DCs and some malignant cells in tumor tissues. Our data revealed the important role of XCR1 in remodeling the tumor microenvironment and predicting the survival prognosis, which could also be used as a sensitive biomarker for tumor immunotherapy.

Mogamulizumab-induced bone granuloma: a multicentre nationwide case series

Our case series reports a new immune-related adverse event and highlights three important facts. Firstly, granulomatous reactions not only occur in the skin, but can also affect bones. Secondly, although possibly transient and spontaneously regressive, such lesions may result in protracted functional disabilities owing to their location and the interest of systemic steroids in this setting remains to be established. Finally, they should not be mistaken with an unfavourable evolution of the underlying disease and seem instead to be associated with protracted responses.

Therapeutic approaches for HTLV-1-associated adult T-cell leukemia/lymphoma: a comprehensive review

Adult T-cell leukemia/lymphoma (ATLL), an infrequent malignancy resultant from human T-cell lymphotropic virus type I (HTLV-1), exhibits a spectrum of phenotypes, encompassing acute, smoldering, lymphomatous, and chronic variants, each bearing distinct clinical presentations. The preponderant acute manifestation is characterized by hypercalcemia, systemic manifestations, organomegaly, and dermatological eruptions. Conversely, the chronic phenotype is typified by lymphocytosis and/or cutaneous eruptions, while smoldering ATLL assumes an asymptomatic course. Immunocompromise afflicts ATLL patients, heightening their vulnerability to opportunistic infections that frequently intricately intertwine with disease progression. Therefore, an early diagnosis is crucial to manage the disease appropriately. While conventional chemotherapeutic regimens have shown limited success, especially in acute and lymphoma types, recent studies suggest that allogeneic stem cell transplantation might enhance treatment results because it has shown promising outcomes in some patients. Novel therapeutics, such as interferon and monoclonal antibodies, have also shown promise, but more research is needed to confirm their efficacy. Moreover, the identification of biomarkers for ATLL and genetic changes in HTLV-1 infected cells has led to the development of targeted therapies that have shown remarkable success in clinical trials. These targeted therapies have the potential to offer a more personalized approach to the treatment of ATLL. The aim of our review is to elaborate on conventional and novel therapies and the efficiency of mentioned treatments.

General structure-activity/selectivity relationship patterns for the inhibitors of the chemokine receptors (CCR1/CCR2/CCR4/CCR5) with application for virtual screening of PubChem database

CC chemokine receptors (CCRs) form a crucial subfamily of G protein-linked receptors that play a distinct role in the onset and progression of various life-threatening diseases. The main aim of this research is to derive general structure-activity relationship (SAR) patterns to describe the selectivity and activity of CCR inhibitors. To this end, a total of 7332 molecules related to the inhibition of CCR1, CCR2, CCR4, and CCR5 were collected from the Binding Database and analyzed using machine learning techniques. A diverse set of 450 molecular descriptors was calculated for each molecule, and the molecules were classified based on their therapeutic targets and activities. The variable importance in the projection (VIP) approach was used to select discriminatory molecular features, and classification models were developed using supervised Kohonen networks (SKN) and counter-propagation artificial neural networks (CPANN). The reliability and predictability of the models were estimated using 10-fold cross-validation, an external validation set, and an applicability domain approach. We were able to identify different sets of molecular descriptors for discriminating between active and inactive molecules and model the selectivity of inhibitors towards different CCRs. The sensitivities of the predictions for the external test set for the SKN models ranged from 0.827-0.873. Finally, the developed classification models were used to screen approximately 2 million random molecules from the PubChem database, with average values for areas under the receiver operating characteristic curves ranging from 0.78-0.96 for SKN models and 0.75-0.89 for CPANN models.Communicated by Ramaswamy H. Sarma.

Role of chemokines in T-cell acute lymphoblastic Leukemia: From pathogenesis to therapeutic options

T-cell acute lymphoblastic leukemia (T-ALL) is a highly heterogeneous and aggressive subtype of hematologic malignancy, with limited therapeutic options due to the complexity of its pathogenesis. Although high-dose chemotherapy and allogeneic hematopoietic stem cell transplantation have improved outcomes for T-ALL patients, there remains an urgent need for novel treatments in cases of refractory or relapsed disease. Recent research has demonstrated the potential of targeted therapies aimed at specific molecular pathways to improve patient outcomes. Chemokine-related signals, both upstream and downstream, modulate the composition of distinct tumor microenvironments, thereby regulating a multitude of intricate cellular processes such as proliferation, migration, invasion and homing. Furthermore, the progress in research has made significant contributions to precision medicine by targeting chemokine-related pathways. This review article summarizes the crucial roles of chemokines and their receptors in T-ALL pathogenesis. Moreover, it explores the advantages and disadvantages of current and potential therapeutic options that target chemokine axes, including small molecule antagonists, monoclonal antibodies, and chimeric antigen receptor T-cells.

Development of tolerance to chemokine receptor antagonists: current paradigms and the need for further investigation

Chemokine G-protein coupled receptors are validated drug targets for many diseases, including cancer, neurological, and inflammatory disorders. Despite much time and effort spent on therapeutic development, very few chemokine receptor antagonists are approved for clinical use. Among potential reasons for the slow progress in developing chemokine receptor inhibitors, antagonist tolerance, a progressive reduction in drug efficacy after repeated administration, is likely to play a key role. The mechanisms leading to antagonist tolerance remain poorly understood. In many cases, antagonist tolerance is accompanied by increased receptor concentration on the cell surface after prolonged exposure to chemokine receptor antagonists. This points to a possible role of altered receptor internalization and presentation on the cell surface, as has been shown for agonist (primarily opioid) tolerance. In addition, examples of antagonist tolerance in the context of other G-protein coupled receptors suggest the involvement of noncanonical signal transduction in opposing the effects of the antagonists. In this review, we summarize the available progress and challenges in therapeutic development of chemokine receptor antagonists, describe the available knowledge about antagonist tolerance, and propose new avenues for future investigation of this important phenomenon. Furthermore, we highlight the modern methodologies that have the potential to reveal novel mechanisms leading to antagonist tolerance and to propel the field forward by advancing the development of potent "tolerance-free" antagonists of chemokine receptors.

Unveiling tumor immune evasion mechanisms: abnormal expression of transporters on immune cells in the tumor microenvironment

The tumor microenvironment (TME) is a crucial driving factor for tumor progression and it can hinder the body's immune response by altering the metabolic activity of immune cells. Both tumor and immune cells maintain their proliferative characteristics and physiological functions through transporter-mediated regulation of nutrient acquisition and metabolite efflux. Transporters also play an important role in modulating immune responses in the TME. In this review, we outline the metabolic characteristics of the TME and systematically elaborate on the effects of abundant metabolites on immune cell function and transporter expression. We also discuss the mechanism of tumor immune escape due to transporter dysfunction. Finally, we introduce some transporter-targeted antitumor therapeutic strategies, with the aim of providing new insights into the development of antitumor drugs and rational drug usage for clinical cancer therapy.

CXCR3 expression in regulatory T cells drives interactions with type I dendritic cells in tumors to restrict CD8+ T cell antitumor immunity

Infiltration of regulatory T (Treg) cells, an immunosuppressive population of CD4+ T cells, into solid cancers represents a barrier to cancer immunotherapy. Chemokine receptors are critical for Treg cell recruitment and cell-cell interactions in inflamed tissues, including cancer, and thus are an ideal therapeutic target. Here, we show in multiple cancer models that CXCR3+ Treg cells were increased in tumors compared with lymphoid tissues, exhibited an activated phenotype, and interacted preferentially with CXCL9-producing BATF3+ dendritic cells (DCs). Genetic ablation of CXCR3 in Treg cells disrupted DC1-Treg cell interactions and concomitantly increased DC-CD8+ T cell interactions. Mechanistically, CXCR3 ablation in Treg cells increased tumor antigen-specific cross-presentation by DC1s, increasing CD8+ T cell priming and reactivation in tumors. This ultimately impaired tumor progression, especially in combination with anti-PD-1 checkpoint blockade immunotherapy. Overall, CXCR3 is shown to be a critical chemokine receptor for Treg cell accumulation and immune suppression in tumors.

Advances in understanding of the pathogenesis and therapeutic implications of drug reaction with eosinophilia and systemic symptoms: an updated review

Drug reaction with eosinophilia and systemic symptoms or drug-induced hypersensitivity syndrome (DRESS/DIHS) is one type of severe cutaneous adverse reaction (SCAR). It is featured by fever, widespread skin lesions, protracted clinical course, internal organ involvement, and possibly long-term autoimmune sequelae. The presence of high-risk human leukocyte antigen (HLA) alleles, hypersensitivity reaction after culprit drug ingestion, and human herpesvirus reactivation may all contribute to its complex clinical manifestations. Some recent studies focusing on the roles of involved cytokines/chemokines and T cells co-signaling pathways in DRESS/DIHS were conducted. In addition, some predictors of disease severity and prognosis were also reported. In this review, we provided an update on the current understanding of the pathogenesis, potential biomarkers, and the relevant therapeutic rationales of DRESS/DIHS.

Shikonin Induces ROS-Dependent Apoptosis Via Mitochondria Depolarization and ER Stress in Adult T Cell Leukemia/Lymphoma

Adult T cell leukemia/lymphoma (ATLL) is an aggressive T-cell malignancy that develops in some elderly human T-cell leukemia virus (HTVL-1) carriers. ATLL has a poor prognosis despite conventional and targeted therapies, and a new safe and efficient therapy is required. Here, we examined the anti-ATLL effect of Shikonin (SHK), a naphthoquinone derivative that has shown several anti-cancer activities. SHK induced apoptosis of ATLL cells accompanied by generation of reactive oxygen species (ROS), loss of mitochondrial membrane potential, and induction of endoplasmic reticulum (ER) stress. Treatment with a ROS scavenger, N-acetylcysteine (NAC), blocked both loss of mitochondrial membrane potential and ER stress, and prevented apoptosis of ATLL cells, indicating that ROS is an upstream trigger of SHK-induced apoptosis of ATLL cells through disruption of the mitochondrial membrane potential and ER stress. In an ATLL xenografted mouse model, SHK treatment suppressed tumor growth without significant adverse effects. These results suggest that SHK could be a potent anti-reagent against ATLL.

Th17/IL-17 Axis in HTLV-1-Associated Myelopathy Tropical Spastic Paraparesis and Multiple Sclerosis: Novel Insights into the Immunity During HAMTSP

Human T lymphotropic virus-associated myelopathy/tropical spastic paraparesis (HTLV/TSP), also known as HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP), and multiple sclerosis (MS) are chronic debilitating diseases of the central nervous system; although the etiology of which is different, similarities have been observed between these two demyelinating diseases, especially in clinical manifestation and immunopathogenesis. Exorbitant response of the immune system to the virus and neurons in CNS is the causative agent of HAM/TSP and MS, respectively. Helper T lymphocyte-17 cells (Th17s), a component of the immune system, which have a proven role in immunity and autoimmunity, mediate protection against bacterial/fungal infections. The role of these cells has been reviewed in several CNS diseases. A pivotal role for Th17s is presented in demyelination, even more axial than Th1s, during MS. The effect of Th17s is not well determined in HTLV-1-associated infections; however, the evidence that we have supplied in this review illustrates the attendance, also the role of Th17 cells during HAM/TSP. Furthermore, for better conception concerning the trace of these cells in HAM/TSP, a comparative characterization with MS, the resembling disease, has been applied here.

Tumor-infiltrating regulatory T cells as targets of cancer immunotherapy

Regulatory T cells (Tregs) are abundant in tumor tissues, raising a question of whether immunosuppressive tumor-infiltrating Tregs (TI-Tregs) can be selectively depleted or functionally attenuated to evoke effective anti-tumor immune responses by conventional T cells (Tconvs), without perturbing Treg-dependent immune homeostasis in healthy organs and causing autoimmunity. Here, we review current cancer immunotherapy strategies, including immune checkpoint blockade (ICB) antibodies against CTLA-4 and PD-1 and discuss their effects on TI-Tregs. We also discuss approaches that exploit differentially regulated molecules on the cell surface (e.g., CTLA-4) and intracellularly (e.g., T cell receptor signaling molecules) between TI-Tregs and Tconvs as well as their dependence on cytokines (e.g., IL-2) and metabolites (e.g., lactate). We envisage that targeting TI-Tregs could be effective as a monotherapy and/or when combined with ICB antibodies.

Immune Checkpoint Inhibitors in HBV-Caused Hepatocellular Carcinoma Therapy

Hepatitis B virus (HBV) infection is the main risk factor for the development of hepatocellular carcinoma (HCC), the most common type of liver cancer, with high incidence and mortality worldwide. Surgery, liver transplantation, and ablation therapies have been used to treat early HBV-caused HCC (HBV-HCC); meanwhile, in the advanced stage, chemoradiotherapy and drug-targeted therapy are regularly considered, but with limited efficacy. Recently, immunotherapies, such as tumor vaccine therapy, adoptive cell transfer therapy, and immune checkpoint inhibitor therapy, have demonstrated promising efficacy in cancer treatment. In particular, immune checkpoint inhibitors can successfully prevent tumors from achieving immune escape and promote an anti-tumor response, thereby boosting the therapeutic effect in HBV-HCC. However, the advantages of immune checkpoint inhibitors in the treatment of HBV-HCC remain to be exploited. Here, we describe the basic characteristics and development of HBV-HCC and introduce current treatment strategies for HBV-HCC. Of note, we review the principles of immune checkpoint molecules, such as programmed cell death protein 1(PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) in HBV-HCC, as well as related inhibitors being considered in the clinic. We also discuss the benefits of immune checkpoint inhibitors in the treatment of HBV-HCC and the efficacy of those inhibitors in HCC with various etiologies, aiming to provide insights into the use of immune checkpoint inhibitors for the treatment of HBV-HCC.

Dynamic Changes in Serum Cytokine Profile in Rats with Severe Acute Pancreatitis

Background and Objectives: Most published research has only investigated a single timepoint after the onset of severe acute pancreatitis (SAP), meaning that they have been unable to observe the relationship between the dynamic changes in cytokines and SAP progression. In this study, we attempted to reveal the relationship between dynamic changes in cytokine expression levels and SAP disease progression and the relationship between cytokines, using continuous large-scale cytokine detection. Materials and Methods: Seventy rats were randomly assigned to control (Con), sham operation (SO) and SAP groups. The SAP group was randomly allocated to five subgroups at 3, 6, 9, 12 and 15 h after the operation. In the SAP group, 5% sodium taurocholate was injected retrograde into the pancreatic bile duct. Animals in the SO group received a similar incision, a turning over of the pancreas. Control animals did not receive any treatment. We observed the survival, ascites fluid amount, pancreatic histopathological scores and serum amylase activity of SAP rats. We used the cytokine microarray to simultaneously detect 90 cytokines and the dynamic changes in one experiment and to analyze the correlation between cytokine expression and disease progression. Results: The mortality of SAP rats increased with an increase in time. Serum amylase activity, pancreatic histopathological scores and ascites fluid amount were time-dependent. Compared with normal rats, 69 cytokines in SAP rats were significantly changed for at least one timepoint, and 49 cytokines were significantly changed at different timepoints after SAP induction. The changes in inflammatory cytokines were significantly upregulated at 6 and 9 h and 12 h and then significantly decreased. Conclusions: The trend of cytokine expression in SAP rats was not consistent with the disease progression. The cytokine-cytokine receptor interaction and MAPK signal's dominant cytokines were always highly expressed at various time points over the course of SAP.

Efficient Redirection of NK Cells by Genetic Modification with Chemokine Receptors CCR4 and CCR2B

Natural killer (NK) cells are a subset of lymphocytes that offer great potential for cancer immunotherapy due to their natural anti-tumor activity and the possibility to safely transplant cells from healthy donors to patients in a clinical setting. However, the efficacy of cell-based immunotherapies using both T and NK cells is often limited by a poor infiltration of immune cells into solid tumors. Importantly, regulatory immune cell subsets are frequently recruited to tumor sites. In this study, we overexpressed two chemokine receptors, CCR4 and CCR2B, that are naturally found on T regulatory cells and tumor-resident monocytes, respectively, on NK cells. Using the NK cell line NK-92 as well as primary NK cells from peripheral blood, we show that genetically engineered NK cells can be efficiently redirected using chemokine receptors from different immune cell lineages and migrate towards chemokines such as CCL22 or CCL2, without impairing the natural effector functions. This approach has the potential to enhance the therapeutic effect of immunotherapies in solid tumors by directing genetically engineered donor NK cells to tumor sites. As a future therapeutic option, the natural anti-tumor activity of NK cells at the tumor sites can be increased by co-expression of chemokine receptors with chimeric antigen receptors (CAR) or T cell receptors (TCR) on NK cells can be performed in the future.

Identification of a tissue resident memory CD8 T cell-related risk score signature for colorectal cancer, the association with TME landscapes and therapeutic responses

Backgrounds: The tissue resident memory CD8 T cell (Trm) constitutes an important component of the local immunity. In the context of malignant tumors, mounting evidence also supports the potential anti-tumor property of this cell subset. Therefore, identification of Trm marker genes and exploration of the causative effect of Trm in shaping tumor microenvironment (TME) heterogeneity might provide novel insights for the comprehensive management of cancer patients. Methods: By dissecting a single T cell transcriptome dataset, we acquired marker genes for Trm, which were latter applied to bulk RNA sequencing profiles of two large colorectal cancer (CRC) patient cohorts downloaded from TCGA and GEO databases. First, colorectal cancer patients were divided into different Trm clusters using consensus clustering algorithm. Then, we established a Trm-related gene (TRMRG) risk score signature and tested its efficacy in predicting prognosis for colorectal cancer patients. Moreover, a sequence of rigorous and robust analyses were also carried out to investigate the potential role of Trm-related gene risk score in tumor microenvironment remodeling and therapeutic utility of it in colorectal cancer treatment. Results: A total of 49 Trm marker genes were identified by analyzing single cell RNA sequencing profiles. First, colorectal cancer patients were successfully classified into two Trm clusters with significant heterogeneity in functional enrichment patterns and tumor microenvironment landscapes. Then, we developed a Trm-related gene risk score signature and divided patients into different risk levels. High risk patients were characterized by attenuated immunogenicity, weakened sensitivity to immunotherapy, as well as adverse clinical outcomes. While low risk patients with advantages in survival exhibited increased immunogenicity, stronger metabolic activity and improved immunotherapeutic responses. Conclusion: Through combinatorial analysis of single cell and bulk RNA sequencing data, the present study identified Trm to play a non-negligible role in regulating the complexity and heterogeneity of tumor microenvironment for colorectal cancer. Moreover, the Trm-related gene risk score signature developed currently was corroborated to be tightly correlated with prognosis and therapeutic responses of colorectal cancer patients, thus exhibiting potential application value for clinical practice.

CCR4 plays a pivotal role in Th17 cell recruitment and expansion in a mouse model of rheumatoid arthritis

T helper 17 (Th17) cells express CC chemokine receptor 4 (CCR4) and secrete cytokines such as interleukin-17A (IL-17A) and granulocyte macrophage colony-stimulating factor (GM-CSF), while dendritic cells (DCs) produce CC chemokine ligand 22 (CCL22), a CCR4 ligand, upon stimulation with GM-CSF. Th17 cells are known to play a critical role in the pathogenesis of rheumatoid arthritis (RA). CCL22 has also been shown to be up-regulated in the synovial tissues of RA patients. Here, we investigated the role of CCR4 in collagen-induced arthritis (CIA), a mouse model of RA. DBA/1J mice efficiently developed CIA as shown by erythema, paw swelling, joint rigidity, and joint destruction. Th17 cells were increased in the arthritic joints and regional lymph nodes (LNs) of CIA mice. A fraction of Th17 cells were also shown to produce GM-CSF. On the other hand, we observed no significant increases of Th2 cells or Treg cells, the T cell subsets also known to express CCR4, in these tissues. We further observed clusters of CCR4-expressing memory Th17 cells and CCL22-producing DCs in the regional LNs of CIA mice, supporting the role of the CCR4-CCL22 axis in the expansion of Th17 cells in the regional LNs. Compound 22, a CCR4 inhibitor, ameliorated the disease severity with reduction of Th17 cells in the arthritic joints and regional LNs and Th17-DC clusters in the regional LNs. We further confirmed that CCR4-deficient mice in the C57BL/6J background were highly resistant to CIA induction compared with wild-type mice. Collectively, CCR4 contributes to the pathogenesis of CIA and may thus represent a new therapeutic target for RA.

Features of Peripheral Blood Th-Cell Subset Composition and Serum Cytokine Level in Patients with Activity-Driven Ankylosing Spondylitis

Th cells may exhibit pathological activity depending on the regulatory and functional signals sensed under a wide range of immunopathological conditions, including ankylosing spondylitis (AS). The relationship between Th cells and cytokines is important for diagnoses and for determining treatment. Accordingly, the aim of this study was to investigate the relationship between Th-cell subset composition and serum cytokine profile for patients with activity-driven AS. In our study, patients were divided into two groups according to disease activity: low-activity AS (ASDAS-CRP < 2.1) and high-activity AS (ASDAS-CRP > 2.1). The peripheral blood Th cell subset composition was studied by flow cytometry. Using multiplex analysis, serum cytokine levels were quantified and investigated. It was found that only patients with high-activity AS had reduced central memory (CM) Th1 cells (p = 0.035) but elevated numbers of CM (p = 0.014) and effector memory (EM) Th2 cells (p < 0.001). However, no activity-driven change in the Th17 cell subset composition was observed in AS patients. Moreover, low-AS activity patients had increased numbers of Tfh17 EM cells (p < 0.001), whereas high-AS activity was associated with elevated Tfh2 EM level (p = 0.031). The serum cytokine profiles in AS patients demonstrated that cues stimulating cellular immunity were increased, but patients with high-AS activity reveled increased IL-5 level (p = 0.017). Analyzing the data obtained from AS patients allowed us to conclude that Th cell subset differentiation was mainly affected during the CM stage and characterized the IL-23/IL-17 regulatory axis, whereas increased humoral immunity was observed in the high-AS activity group.

Role of SERCA3 in the Prognosis and Immune Function in Pan-Cancer

The sarcoendoplasmic reticulum calcium adenosine triphosphatase (ATPase) 3 (SERCA3), a member of the SERCA protein family, is located at the endoplasmic reticulum. Its main function is to pump Ca2+ into the endoplasmic reticulum and is involved in maintaining intracellular calcium homeostasis and signal transduction, which are very important factors impacting cancer development and progression. However, the specific role of SERCA3 in cancer remains unclear. Our study, for the first time, comprehensively analyzed the SERCA3 expression profile in multiple cancers and its prognostic value in different cancers using bioinformatics. Furthermore, TCGA database was applied to evaluate the certain correlation of SERCA3 expression with immune modulator genes, immune checkpoints, immune cell infiltration, TMB, and MSI. The results revealed that in many cancers, SERCA3 expression was markedly decreased, which was related to poor prognosis. Additionally, we noticed that SERCA3 expression was correlated with TNM classification and WHO cancer stages in some cancer types. The Pearson correlation analysis showed that SERCA3 expression was closely associated with chemokines, chemokine receptors, MHC, immune activation genes, and immunosuppressive genes. In most cancer types, SERCA3 expression was also associated with immune checkpoints, including PDCD1 and CTLA-4. Further analysis suggested that SERCA3 was significantly correlated with CD8+ T cells, and regulatory T cells. Additionally, pan-cancer analysis confirmed that SERCA3 expression was related to TMB and MSI. In conclusion, these results offer a new insight into the functions and effects of SERCA3 in pan-cancer, and further provide some basis for considering SERCA3 as a potential cancer treatment target and biomarker.

An inflammation-related signature could predict the prognosis of patients with kidney renal clear cell carcinoma

Background: Kidney renal clear cell carcinoma (KIRC) is an inflammation-related carcinoma, and inflammation has been recognized as an important factor in inducing carcinogenesis. To further explore the role of inflammation in KIRC, we developed an inflammation-related signature and verified its correlation with the tumor micro-environment.

Methods: After the differential inflammation-related prognostic genes were screened by Lasso regression, the inflammation-related signature (IRS) was constructed based on the risk score of multivariate Cox regression. Then, the prognostic value of the IRS was evaluated by Kaplan-Meier analysis, receiver operating characteristic (ROC) curve analysis and multivariate Cox regression. Gene set variation analysis (GSVA) was applied to screen out enriched signaling pathways. Infiltrated immune cells, tumor mutational burden (TMB) and immune checkpoints were explored by CIBERSORTx and maftool.

Results: Four genes (TIMP1, PLAUR, CCL22, and IL15RA) were used to construct the IRS in patients with KIRC. Kaplan-Meier analysis and multivariate Cox regression identified that the IRS could independently predict the prognosis of patients with KIRC in the training and validation groups. The diagnostic value of the nomogram increased from 0.811 to 0.845 after adding the IRS to the multiparameter ROC analysis. The GSVA results indicated that IRS was closely related to primary immunodeficiency and antigen processing and presentation. The immune checkpoint LAG3 was highly expressed in patients with high-risk score (p < 0.05), while CD274 (PD-L1) and HAVCR2 were highly expressed in patients with low-risk score (p < 0.001). There was a significant positive correlation between the high-risk score group and CD8⁺ T, activated CD4⁺ memory T, gamma and delta regulatory T and M0 macrophage cells, while the low-risk score group was negatively associated with B memory, plasma, resting CD4⁺ memory T, activated NK, M1 macrophages and resting mast cells.

Conclusion: We found that the IRS might serve as a biomarker to predict the survival of KIRC. Moreover, patients with high or low-risk score might be sensitive to immune drugs at different immune checkpoints.

Chemokine receptor 4 expression on blood T lymphocytes predicts severity of major depressive disorder

BACKGROUND

Chemokines and their receptors regulate inflammatory processes in major depressive disorder (MDD). Here, we characterize the expression pattern of the C-C chemokine receptor 4 (CCR4) and its ligands CCL17 and CCL22 in MDD and its clinical relevance in predicting disease severity.

METHODS

Expression of CCR4 on peripheral blood lymphocytes and serum CCL17/CCL22 levels were measured using multiparameter flow cytometry and multiplex assays in 33 depressed inpatients at baseline (T0) and after 6-week multimodal treatment (T1) compared with 21 healthy controls (HC). Using stratified and correlation analysis, we examined the associations of CCR4-CCL17/CCL22 expression with depression severity and symptoms according to standard clinical rating scales and questionnaires. Additionally, we assessed whether polygenic risk score (PRS) for psychiatric disorders and chronotype are associated with disease status or CCR4-CCL17/CCL22 expression. Regression analysis was performed to assess the capacity of CCR4 and PRS in predicting disease severity.

RESULTS

Compared with HC, MDD patients showed significantly decreased CCR4 expression on T cells (T0 and T1), whereas CCL17/CCL22 serum levels were increased. Stratified and correlation analysis revealed an association of CCR4 expression on CD4⁺ T cells with depression severity as well as Beck Depression Inventory-II items including loss of pleasure, agitation and cognitive deficits. CCR4 expression levels on CD4⁺ T cells together with cross-disorder and chronotype PRS significantly predicted disease severity.

LIMITATIONS

This exploratory study with small sample size warrants future studies.

CONCLUSIONS

This newly identified CCR4-CCL17/CCL22 signature and its predictive capacity for MDD severity suggest its potential functional involvement in the pathophysiology of MDD.

FoxP3+ CD8 T-cells in acute HIV infection and following early antiretroviral therapy initiation

Objectives

Besides CD4 regulatory T-cells (Tregs), immunosuppressor FoxP3+ CD8 T-cells are emerging as an important subset of Tregs, which contribute to immune dysfunction and disease progression in HIV infection. However, FoxP3+ CD8 T-cell dynamics in acute HIV infection and following early antiretroviral therapy (ART) initiation remain understudied.

Methods

Subsets of FoxP3+ CD8 T-cells were characterized both prospectively and cross-sectionally in PBMCs from untreated acute (n=26) and chronic (n=10) HIV-infected individuals, early ART-treated in acute infection (n=10, median of ART initiation: 5.5 months post-infection), ART-treated in chronic infection (n=10), elite controllers (n=18), and HIV-uninfected controls (n=21).

Results

Acute and chronic infection were associated with increased total, effector memory, and terminally differentiated FoxP3+ CD8 T-cells, while early ART normalized only the frequencies of total FoxP3+ CD8 T-cells. We observed an increase in FoxP3+ CD8 T-cell immune activation (HLADR+/CD38+), senescence (CD57+/CD28-), and PD-1 expression during acute and chronic infection, which were not normalized by early ART. FoxP3+ CD8 T-cells in untreated participants expressed higher levels of immunosuppressive LAP(TGF-β1) and CD39 than uninfected controls, whereas early ART did not affect their expression. The expression of gut-homing markers CCR9 and Integrin-β7 by total FoxP3+ CD8 T-cells and CD39+ and LAP(TGF-β1)+ FoxP3+ CD8 T-cells increased in untreated individuals and remained higher than in uninfected controls despite early ART. Elite controllers share most of the FoxP3+ CD8 T-cell characteristics in uninfected individuals.

Conclusions

Although early ART normalized total FoxP3+ CD8 T-cells frequencies, it did not affect the persistent elevation of the gut-homing potential of CD39+ and LAP(TGF-β1)+ FoxP3+ CD8 T-cell, which may contribute to immune dysfunction.

Emerging Roles of Chemokines in Cancer Immunotherapy

This series of 15 articles (4 original articles and 11 reviews) is presented by international leaders in chemokine research [...]

Mesenchymal Stromal Cells (MSCs): An Ally of B-Cell Acute Lymphoblastic Leukemia (B-ALL) Cells in Disease Maintenance and Progression within the Bone Marrow Hematopoietic Niche

Simple Summary

B-cell acute lymphoblastic leukemia (B-ALL) is the most common pediatric cancer. Even though the cure rate actually exceeds 85%, the prognosis of relapsed/refractory patients is dismal. Recent literature data indicate that the bone marrow (BM) microenvironment could play a crucial role in the onset, maintenance and progression of the disease. In particular, mesenchymal stromal cells (MSCs), which are key components of the BM niche, actively crosstalk with leukemic cells providing crucial signals for their survival and resistance to therapy. We hereby review the main mechanisms exploited by MSCs to nurture and protect B-ALL cells that could become appealing targets for innovative microenvironment remodeling therapies to be coupled with classical leukemia-directed strategies.

Abstract

Mesenchymal stromal cells (MSCs) are structural components of the bone marrow (BM) niche, where they functionally interact with hematopoietic stem cells and more differentiated progenitors, contributing to hematopoiesis regulation. A growing body of evidence is nowadays pointing to a further crucial contribution of MSCs to malignant hematopoiesis. In the context of B-cell acute lymphoblastic leukemia (B-ALL), MSCs can play a pivotal role in the definition of a leukemia-supportive microenvironment, impacting on disease pathogenesis at different steps including onset, maintenance and progression. B-ALL cells hijack the BM microenvironment, including MSCs residing in the BM niche, which in turn shelter leukemic cells and protect them from chemotherapeutic agents through different mechanisms. Evidence is now arising that altered MSCs can become precious allies to leukemic cells by providing nutrients, cytokines, pro-survivals signals and exchanging organelles, as hereafter reviewed. The study of the mechanisms exploited by MSCs to nurture and protect B-ALL blasts can be instrumental in finding new druggable candidates to target the leukemic BM microenvironment. Some of these microenvironment-targeting strategies are already in preclinical or clinical experimentation, and if coupled with leukemia-directed therapies, could represent a valuable option to improve the prognosis of relapsed/refractory patients, whose management represents an unmet medical need.

Comprehensive Analysis of Ferroptosis- and Immune-Related Signatures to Improve the Prognosis and Diagnosis of Kidney Renal Clear Cell Carcinoma

Background

Almost 40% of patients with kidney renal clear cell carcinoma (KIRC) with advanced cancers eventually develop to metastases, and their 5-year survival rates are approximately 10%. Aberrant DNA methylations are significantly associated with the development of KIRC. The aim of our present study was to identify suitable ferroptosis- and immune-related (FI) biomarkers correlated with aberrant methylations to improve the prognosis and diagnosis of KIRC.

Methods

ChAMP and DESeq2 in R (3.6.2) were used to screen the differentially expressed methylation probes and differentially expressed genes, respectively. Univariate and multivariate Cox regression were used to identify the overall survival (OS)-related biomarkers.

Results

We finally identified five FI biomarkers (CCR4, CMTM3, IFITM1, MX2, and NR3C2) that were independently correlated with the OS of KIRC. The area under the curve value of the receiver operating characteristic value of prognosis model was 0.74, 0.68, and 0.72 in the training, validation, and entire cohorts, respectively. The sensitivity and specificity of the diagnosis model were 0.8698 and 0.9722, respectively. In addition, the prognosis model was also significantly correlated with several immune cells and factors.

Conclusion

Our present study suggested that these five FI-DEGs (CCR4, CMTM3, IFITM1, MX2, and NR3C2) could be used as prognosis and diagnosis biomarkers for patients with KIRC, but further cross-validation clinical studies are still needed to confirm them.

Development of a Novel Anti-Mouse CCR4 Monoclonal Antibody (C4Mab-1) by N-Terminal Peptide Immunization

The CC chemokine receptor type-4 (CCR4) belongs to the G-protein-coupled receptor superfamily, expressed on the cell surface of T cells and its malignancy. Two CCR4 ligands (CCL17 and CCL22) bind to CCR4 that mediate physiological and pathological functions of T cell immune responses. Anti-CCR4 monoclonal antibody (mAb) mogamulizumab is approved for adult T cell leukemia/lymphoma and cutaneous T cell lymphomas. In addition, mogamulizumab can deplete regulatory T cells, implying the application to solid tumors as an immunomodulator. Therefore, the development of sensitive mAbs for CCR4 has been desired for basic research, diagnosis, and therapy. In this study, a specific, and sensitive anti-mouse CCR4 (mCCR4) mAb, C₄Mab-1 (rat IgG₁, kappa), was established using N-terminal peptide immunization. C₄Mab-1 reacted with mCCR4-overexpressed Chinese hamster ovary (CHO)-K1 cells, P388 (mouse lymphoid neoplasm), and J774-1 (mouse macrophage-like) cells in flow cytometry. Kinetic analyses using flow cytometry showed that K_Ds of C₄Mab-1 for CHO/mCCR4, P388, and J774-1 cells were 4.2 × 10^-9 M, 5.4 × 10^-7 M, and 1.1 × 10^-6 M, respectively. C₄Mab-1 could be a valuable tool for elucidating mCCR4-related biological responses.

Tumor Cell-Autonomous Pro-Metastatic Activities of PD-L1 in Human Breast Cancer Are Mediated by PD-L1-S283 and Chemokine Axes

Simple Summary

Triple-negative breast cancer (TNBC) is an aggressive disease that responds in a limited manner to immune checkpoint blockades targeting the PD-L1/PD-1 axis, suggesting that PD-L1 potentiates TNBC progression via pathways not related to immune suppression. We demonstrated that, in human breast cancer cells, PD-L1 expression increased in a cell-autonomous manner tumor cell growth, invasion and release of pro-metastatic factors; these activities were elevated by exposure to PD-1 and were markedly impaired in S283-mutated PD-L1-expressing cells. Invasion of WT-PD-L1-expressing TNBC cells depended on autocrine chemokine circuits, involving CXCR1/2, CCR2, CCR5 and their ligands. In T cell-deficient mice, WT-PD-L1 exhibited increased tumor growth and metastasis by TNBC cells, whereas S283A-PD-L1-expressing cells showed a very poor tumorigenic and metastatic profile. These findings on cell-autonomous and PD-1-induced pro-metastatic activities of PD-L1 in cancer cells suggest that treatments targeting PD-L1 could improve the efficacy of immune-targeting checkpoint inhibitors, e.g., anti-PD-1 or anti-CTLA-4 in TNBC.

Abstract

Therapies targeting the PD-L1/PD-1 axis have recently been introduced to triple-negative breast cancer (TNBC) with limited efficacy, suggesting that this axis promotes tumor progression through mechanisms other than immune suppression. Here, we over-expressed WT-PD-L1 in human TNBC cells (express endogenous PD-L1) and in luminal-A breast cancer cells (no endogenous PD-L1 expression) and demonstrated that cell-autonomous PD-L1 activities lead to increased tumor cell growth, invasion and release of pro-metastatic factors (CXCL8, sICAM-1, GM-CSF). These activities were promoted by PD-1 and were inhibited by mutating S283 in PD-L1. Invasion of WT-PD-L1-cells required signaling by chemokine receptors CXCR1/2, CCR2 and CCR5 through autocrine circuits involving CXCL8, CCL2 and CCL5. Studies with T cell-deficient mice demonstrated that cell-autonomous WT-PD-L1 activities in TNBC cells increased tumor growth and metastasis compared to knock-out (KO)-PD-L1-cells, whereas S283A-PD-L1-expressing cells had minimal ability to form tumors and did not metastasize. Overall, our findings reveal autonomous and PD-1-induced tumor-promoting activities of PD-L1 that depend on S283 and on chemokine circuits. These results suggest that TNBC patients whose tumors express PD-L1 could benefit from therapies that prevent immune suppression by targeting PD-1/CTLA-4, alongside with antibodies to PD-L1, which would allow maximal impact by mainly targeting the cancer cells.

The Chemokine System in Oncogenic Pathways Driven by Viruses: Perspectives for Cancer Immunotherapy

Simple Summary

Oncoviruses are viruses with oncogenic potential, responsible for almost 20% of human cancers worldwide. They are from various families, some of which belong to the microbial communities that inhabit several sites in the body of healthy humans. As a result, they most often establish latent infections controlled by the arsenal of human host responses that include the chemokine system playing key roles at the interface between tissue homeostasis and immune surveillance. Yet, chemokines and their receptors also contribute to oncogenic processes as they are targeted by the virus-induced deregulations of host responses and/or directly encoded by viruses. Thus, the chemokine system offers a strong rationale for therapeutic options, some few already approved or in trials, and future ones that we are discussing in view of the pharmacological approaches targeting the different functions of chemokines operating in both cancer cells and the tumor microenvironment.

Abstract

Chemokines interact with glycosaminoglycans of the extracellular matrix and activate heptahelical cellular receptors that mainly consist of G Protein-Coupled Receptors and a few atypical receptors also with decoy activity. They are well-described targets of oncogenic pathways and key players in cancer development, invasiveness, and metastasis acting both at the level of cancer cells and cells of the tumor microenvironment. Hence, they can regulate cancer cell proliferation and survival and promote immune or endothelial cell migration into the tumor microenvironment. Additionally, oncogenic viruses display the potential of jeopardizing the chemokine system by encoding mimics of chemokines and receptors as well as several products such as oncogenic proteins or microRNAs that deregulate their human host transcriptome. Conversely, the chemokine system participates in the host responses that control the virus life cycle, knowing that most oncoviruses establish asymptomatic latent infections. Therefore, the deregulated expression and function of chemokines and receptors as a consequence of acquired or inherited mutations could bias oncovirus infection toward pro-oncogenic pathways. We here review these different processes and discuss the anticancer therapeutic potential of targeting chemokine availability or receptor activation, from signaling to decoy-associated functions, in combination with immunotherapies.

Multifaceted Roles of Chemokines and Chemokine Receptors in Tumor Immunity

Simple Summary

Various immune cells are involved in host immune responses to cancer. T-helper (Th) 1 cells, cytotoxic CD8⁺ T cells, and natural killer cells are the major effector cells in anti-tumor immunity, whereas cells such as regulatory T cells and myeloid-derived suppressor cells are negatively involved in anti-tumor immunity. Th2 cells and Th17 cells have been shown to have both pro-tumor and anti-tumor activities. The migratory properties of various immune cells are essential for their function and critically regulated by the chemokine superfamily. In this review, we summarize the roles of various immune cells in tumor immunity and their migratory regulation by the chemokine superfamily. We also assess the therapeutic possibilities of targeting chemokines and chemokine receptors in cancer immunotherapy.

Abstract

Various immune cells are involved in host tumor immune responses. In particular, there are many T cell subsets with different roles in tumor immunity. T-helper (Th) 1 cells are involved in cellular immunity and thus play the major role in host anti-tumor immunity by inducing and activating cytotoxic T lymphocytes (CTLs). On the other hand, Th2 cells are involved in humoral immunity and suppressive to Th1 responses. Regulatory T (Treg) cells negatively regulate immune responses and contribute to immune evasion of tumor cells. Th17 cells are involved in inflammatory responses and may play a role in tumor progression. However, recent studies have also shown that Th17 cells are capable of directly inducting CTLs and thus may promote anti-tumor immunity. Besides these T cell subsets, there are many other innate immune cells such as dendritic cells (DCs), natural killer (NK) cells, and myeloid-derived suppressor cells (MDSCs) that are involved in host immune responses to cancer. The migratory properties of various immune cells are critical for their functions and largely regulated by the chemokine superfamily. Thus, chemokines and chemokine receptors play vital roles in the orchestration of host immune responses to cancer. In this review, we overview the various immune cells involved in host responses to cancer and their migratory properties regulated by the chemokine superfamily. Understanding the roles of chemokines and chemokine receptors in host immune responses to cancer may provide new therapeutic opportunities for cancer immunotherapy.