Role of chemokines and chemokine receptors in shaping the effector phase of the antitumor immune response

Engineered CD4 T cells for in vivo delivery of therapeutic proteins

The CD4 T cell, when engineered with a chimeric antigen receptor (CAR) containing specific intracellular domains, has been transformed into a zero-order drug-delivery platform. This introduces the capability of prolonged, disease-specific engineered protein biologics production, at the disease site. Experimental findings demonstrate that CD4 T cells offer a solution when modified with a CAR that includes 4-1BB but excludes CD28 intracellular domain. In this configuration, they achieve ~3X transduction efficiency of CD8 T cells, ~2X expansion rates, generating ~5X more biologic, and exhibit minimal cytolytic activity. Cumulatively, this addresses two main hurdles in the translation of cell-based drug delivery: scaling the production of engineered T cell ex vivo and generating sufficient biologics in vivo. When programmed to induce IFNβ upon engaging the target antigen, the CD4 T cells outperforms CD8 T cells, effectively suppressing cancer cell growth in vitro and in vivo. In summary, this platform enables precise targeting of disease sites with engineered protein-based therapeutics while minimizing healthy tissue exposure. Leveraging CD4 T cells' persistence could enhance disease management by reducing drug administration frequency, addressing critical challenges in cell-based therapy.

DNA hypo-methylation and expression of GBP4 induces T cell exhaustion in pancreatic cancer

Immunotherapy for pancreatic ductal carcinoma (PDAC) remains disappointing due to the repressive tumor microenvironment and T cell exhaustion, in which the roles of interferon-stimulated genes were largely unknown. Here, we focused on a typical interferon-stimulated gene, GBP4, and investigated its potential diagnostic and therapeutic value in pancreatic cancer. Expression analysis on both local samples and public databases indicated that GBP4 was one of the most dominant GBP family members present in the PDAC microenvironment, and the expression level of GBP4 was negatively associated with patient survival. We then identified DNA hypo-methylation in regulatory regions of GBP4 in PDAC, and validated its regulatory role on GBP4 expression via performing targeted methylation using dCas9-SunTag-DNMAT3A-sgRNA-targeted methylation system on selected DNA locus. After that, we investigated the downstream functions of GBP4, and chemotaxis assays indicated that GBP4 overexpression significantly improved the infiltration of CD8+T cells, but also induced upregulation of immune checkpoint genes and T cell exhaustion. Lastly, in vitro T cell killing assays using primary organoids suggested that the PDAC samples with high level of GBP4 expression displayed significantly higher sensitivity to anti-PD-1 treatment. Taken together, our studies revealed the expression patterns and epigenetic regulatory mechanisms of GBP4 in pancreatic cancer and clarified the effects of GBP4 on T cell exhaustion and antitumor immunology.

Prognostic and Predictive Potential of CCL5 Expression in Muscle-Invasive Bladder Cancer Patients

Bladder cancer (BC) is the 12th most commonly diagnosed cancer worldwide. Although there are several well-established molecular and immunological classifications, prognostic and predictive markers for tumor cells and immune cells are still needed. Using a tissue microarray, we analyzed the expression of the chemokine CC motif ligand 5 (CCL5) by immunohistochemistry (IHC) in 175 muscle-invasive BC samples. The application of a single cutoff for the staining status of tumor cells (TCs; positive vs. negative) and immune cells (ICs; positive vs. negative) revealed 75 patients (42.9%) and 123 patients (70.3%) with CCL5-positive TCs or ICs, respectively. IHC results were associated with prognostic and predictive data. Multivariate Cox regression analysis revealed that positive CCL5 staining in TCs was associated with significantly shorter disease-specific survival (DSS; RR = 1.51; p = 0.047), but CCL5-negative ICs were associated with significantly shorter overall survival (OS; RR = 1.66; p = 0.005), DSS (RR = 2.02; p = 0.001) and recurrence-free survival (RFS; RR = 1.94; p = 0.002). Adjuvant chemotherapy was favorable for patients with CCL5-negative ICs for OS (RR = 0.30; p = 0.006), DSS (RR = 0.36; p = 0.022) and RFS (RR = 0.41; p = 0.046) but not for patients with CCL5-positive ICs, except in the subgroup of N1 + N2 patients, where it was associated with better OS. We suggest that CCL5 expression can be a prognostic and predictive marker for muscle-invasive bladder cancer patients.

Kaempferol Alleviates Hepatic Injury in Nonalcoholic Steatohepatitis (NASH) by Suppressing Neutrophil-Mediated NLRP3-ASC/TMS1-Caspase 3 Signaling

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a significant hepatic condition that has gained worldwide attention. Kaempferol (Kae), renowned for its diverse biological activities, including anti-inflammatory, antioxidant, anti-aging, and cardio-protective properties, has emerged as a potential therapeutic candidate for non-alcoholic steatohepatitis (NASH). Despite its promising therapeutic potential, the precise underlying mechanism of Kae's beneficial effects in NASH remains unclear. Therefore, this study aims to clarify the mechanism by conducting comprehensive in vivo and in vitro experiments.

RESULTS

In this study, a murine model of non-alcoholic steatohepatitis (NASH) was established by feeding C57BL/6 female mice a high-fat diet for 12 weeks. Kaempferol (Kae) was investigated for its ability to modulate systemic inflammatory responses and lipid metabolism in this model (20 mg/kg per day). Notably, Kae significantly reduced the expression of NLRP3-ASC/TMS1-Caspase 3, a crucial mediator of liver tissue inflammation. Additionally, in a HepG2 cell model induced with palmitic acid/oleic acid (PA/OA) to mimic NASH conditions, Kae demonstrated the capacity to decrease lipid droplet accumulation and downregulate the expression of NLRP3-ASC/TMS1-Caspase 3 (20 µM and the final concentration to 20 nM). These findings suggest that Kae may hold therapeutic potential in the treatment of NASH by targeting inflammatory and metabolic pathways.

CONCLUSIONS

These findings suggest that kaempferol holds potential as a promising therapeutic intervention for ameliorating non-alcoholic fatty liver disease (NAFLD).

CXCL10 and IL15 co-expressing chimeric antigen receptor T cells enhance anti-tumor effects in gastric cancer by increasing cytotoxic effector cell accumulation and survival

Chimeric antigen receptor (CAR) T cells have demonstrated outstanding therapeutic success in hematological malignancies. Yet, their efficacy against solid tumors remains constrained due to inadequate infiltration of cytotoxic T and CAR-T cells in the tumor microenvironment (TME), a factor correlated with poor prognosis in patients with solid tumors. To overcome this limitation, we engineered CAR-T cells to secrete CXCL10 and IL15 (10 × 15 CAR-T), which sustain T cell viability and enhance their recruitment, thereby amplifying the long-term cytotoxic capacity of CAR-T cells in vitro. In a xenograft model employing NUGC4-T21 cells, mice receiving 10 × 15 CAR-T cells showed superior tumor reduction and extended survival rates compared to those treated with second-generation CAR-T cells. Histopathological evaluations indicated a pronounced increase in cytotoxic T cell accumulation in the TME post 10 × 15 CAR-T cell treatment. Therefore, the synergistic secretion of CXCL10 and IL15 in these CAR-T cells enhances T cell recruitment and adaptability within tumor tissues, improving tumor control. This approach may offer a promising strategy for advancing CAR-T therapies in the treatment of solid tumors.

Circulating T cells: a promising biomarker of anti-PD-(L)1 therapy

Anti-PD-(L)1 therapy has shown great efficacy in some patients with cancer. However, a significant proportion of patients with cancer do not respond to it. Another unmet clinical need for anti-PD-(L)1 therapy is the dynamic monitoring of treatment effects. Therefore, identifying biomarkers that can stratify potential responders before PD-(L)1 treatment and timely monitoring of the efficacy of PD-(L)1 treatment are crucial in the clinical setting. The identification of biomarkers by liquid biopsy has attracted considerable attention. Among the identified biomarkers, circulating T cells are one of the most promising because of their indispensable contribution to anti-PD-(L)1 therapy. The present review aimed to thoroughly explore the potential of circulating T cells as biomarkers of anti-PD-(L)1 therapy and its advantages and limitations.

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.

Epigenomic analyses identify FOXM1 as a key regulator of anti-tumor immune response in esophageal adenocarcinoma

Unlike most cancer types, the incidence of esophageal adenocarcinoma (EAC) has rapidly escalated in the western world over recent decades. Using whole genome bisulfite sequencing (WGBS), we identify the transcription factor (TF) FOXM1 as an important epigenetic regulator of EAC. FOXM1 plays a critical role in cellular proliferation and tumor growth in EAC patient-derived organoids and cell line models. We identify ERBB2 as an upstream regulator of the expression and transcriptional activity of FOXM1. Unexpectedly, gene set enrichment analysis (GSEA) unbiased screen reveals a prominent anti-correlation between FOXM1 and immune response pathways. Indeed, syngeneic mouse models show that FOXM1 inhibits the infiltration of CD8+ T cells into the tumor microenvironment. Consistently, FOXM1 suppresses CD8+ T cell chemotaxis in vitro and antigen-dependent CD8+ T cell killing. This study characterizes FOXM1 as a significant EAC-promoting TF and elucidates its novel function in regulating anti-tumor immune response.

Motility and tumor infiltration are key aspects of invariant natural killer T cell anti-tumor function

Dysfunction of invariant natural killer T (iNKT) cells contributes to immune resistance of tumors. Most mechanistic studies focus on their static functional status before or after activation, not considering motility as an important characteristic for antigen scanning and thus anti-tumor capability. Here we show via intravital imaging, that impaired motility of iNKT cells and their exclusion from tumors both contribute to the diminished anti-tumor iNKT cell response. Mechanistically, CD1d, expressed on macrophages, interferes with tumor infiltration of iNKT cells and iNKT-DC interactions but does not influence their intratumoral motility. VCAM1, expressed by cancer cells, restricts iNKT cell motility and inhibits their antigen scanning and activation by DCs via reducing CDC42 expression. Blocking VCAM1-CD49d signaling improves motility and activation of intratumoral iNKT cells, and consequently augments their anti-tumor function. Interference with macrophage-iNKT cell interactions further enhances the anti-tumor capability of iNKT cells. Thus, our findings provide a direction to enhance the efficacy of iNKT cell-based immunotherapy via motility regulation.

Ginsenoside Rh2 augmented anti-PD-L1 immunotherapy by reinvigorating CD8+ T cells via increasing intratumoral CXCL10

Profiting from the sustained clinical improvement and prolonged patient survival, immune checkpoint blockade of programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) axis has emerged as a revolutionary cancer therapy approach. However, the anti-PD-1/PD-L1 antibodies only achieve a clinical response rate of approximately 20%. Herein, we identified a novel combination strategy that Chinese medicine ginseng-derived ginsenoside Rh2 (Rh2) markedly improved the anti-cancer efficacy of anti-PD-L1 antibody in mice bearing MC38 tumor. Rh2 combined with anti-PD-L1 antibody (combo treatment) further triggered the infiltration, proliferation and activation of CD8+ T cells in the tumor microenvironment (TME). Depletion of CD8+ T cells by mouse CD8 blocking antibody abolished the anti-cancer effect of combo treatment totally. Mechanistically, combo treatment further increased the expression of CXCL10 through activating TBK1-IRF3 signaling pathway, explaining the increased infiltration of T cells. Employing anti- CXC chemokine receptor 3 (CXCR3) blocking antibody prevented the T cells infiltration and abolished the anti-cancer effect of combo treatment. Meanwhile, combo treatment increased the percentage of M1-like macrophages and raised the ratio of M1/M2 macrophages in TME. By comparing the anti-cancer effect of combo treatment among MC38, CT26 and 4T1 tumors, resident T cells were considered as a prerequisite for the effectiveness of combo treatment. These findings demonstrated that Rh2 potentiated the anti-cancer effect of PD-L1 blockade via promoting the T cells infiltration and activation, which shed a new light on the combination strategy to enhance anti-PD-L1 immunotherapy by using natural product Rh2.

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.

Elevated expression of CXCL3 in colon cancer promotes malignant behaviors of tumor cells in an ERK-dependent manner

BACKGROUND

CXC chemokine ligand 3 (CXCL3) is a member of CXC-type chemokine family that is identified as a major regulator in immune and inflammation responses. Recently, numerous evidence indicated that CXCL3 is broadly expressed in various human tumor types, and it is also known to play a critical role in mediating tumor development and progression. However, the expression profile of CXCL3 and the exact molecular mechanism behind the role of CXCL3 in colon adenocarcinoma (COAD) has not been fully elucidated.

METHODS

The expression and clinical significance of CXCL3 mRNA and protein in the tissues from COAD patients were estimated using bioinformatics and immunohistochemistry assays. The expression and roles of exogenous administration or overexpression of CXCL3 in HT-29 and SW480 COAD cells were determined using enzyme-linked immunosorbent assay(ELISA), Cell Counting Kit-8 (CCK-8) and Transwell assays. Mechanically, CXCL3-induced malignant behaviors were elucidated using western blotting assay and extracellular signal-regulated protein kinase 1/2 (ERk1/2) inhibitor PD98059.

RESULTS

The cancer genome atlas (TCGA)-COAD data analysis revealed that CXCL3 mRNA is highly expressed and has high clinical diagnostic accuracy in COAD. Increased expression of CXCL3 mRNA was associated with patient's clinical stage, race, gender, age, histological subtype, nodal mestastasis and tumor protein 53 (TP53) mutation status. Similarly, immunohistochemistry assay also exhibited that CXCL3 protein in COAD tissues was significantly up-regulated. Gene expression associated assay implied that CXC chemokine ligand 1 (CXCL1) and CXC chemokine ligand 2 (CXCL2) were markedly correlated with CXCL3 in COAD. Protein-protein interaction (PPI) analysis revealed that cyclin B1 (CCNB1), mitotic arrest deficient 2 like 1 (MAD2L1), H2A family member Z (H2AFZ) and CXCL2 may be the important protein molecules involved in CXCL3-related tumor biology. Gene set enrichment analysis (GSEA) analysis revealed that CXCL3 was mainly enriched in the cell cycle, DNA replication, NOD-like receptors, NOTCH and transforming growth factor-β (TGF-β) Signal pathways. In vitro, exogenous administration or overexpression of CXCL3 resulted in increased malignant behaviors of HT-29 and SW480 cells, and down-regulation of CXCL3 expression inhibited the malignant behaviors of these tumor cells. In addition, overexpression of CXCL3 affected the expression of genes related to extracellular signal regulated kinase (ERK) pathway, including ERK1/2, p-ERK, B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax) and Cyclin D1. Finally, CXCL3-induced malignant behaviors in HT-29 and SW480 cells were obviously attenuated following treatment with ERK inhibitor PD98059.

CONCLUSION

CXCL3 is upregulated in COAD and plays a crucial role in the control of malignant behaviors of tumor cells, which indicated its involvement in the pathogenesis of COAD.

Therapeutic cancer vaccination against mutant calreticulin in myeloproliferative neoplasms induces expansion of specific T cells in the periphery but specific T cells fail to enrich in the bone marrow

Background

Therapeutic cancer vaccination against mutant calreticulin (CALR) in patients with CALR-mutant (CALRmut) myeloproliferative neoplasms (MPN) induces strong T-cell responses against mutant CALR yet fails to demonstrate clinical activity. Infiltration of tumor specific T cells into the tumor microenvironment is needed to attain a clinical response to therapeutic cancer vaccination.

Aim

Determine if CALRmut specific T cells isolated from vaccinated patients enrich in the bone marrow upon completion of vaccination and explore possible explanations for the lack of enrichment.

Methods

CALRmut specific T cells from four of ten vaccinated patients were expanded, enriched, and analyzed by T-cell receptor sequencing (TCRSeq). The TCRs identified were used as fingerprints of CALRmut specific T cells. Bone marrow aspirations from the four patients were acquired at baseline and at the end of trial. T cells were enriched from the bone marrow aspirations and analyzed by TCRSeq to identify the presence and fraction of CALRmut specific T cells at the two different time points. In silico calculations were performed to calculate the ratio between transformed cells and effector cells in patients with CALRmut MPN.

Results

The fraction of CALRmut specific T cells in the bone marrow did not increase upon completion of the vaccination trial. In general, the T cell repertoire in the bone marrow remains relatively constant through the vaccination trial. The enriched and expanded CALRmut specific T cells recognize peripheral blood autologous CALRmut cells. In silico analyses demonstrate a high imbalance in the fraction of CALRmut cells and CALRmut specific effector T-cells in peripheral blood.

Conclusion

CALRmut specific T cells do not enrich in the bone marrow after therapeutic cancer peptide vaccination against mutant CALR. The specific T cells recognize autologous peripheral blood derived CALRmut cells. In silico analyses demonstrate a high imbalance between the number of transformed cells and CALRmut specific effector T-cells in the periphery. We suggest that the high burden of transformed cells in the periphery compared to the number of effector cells could impact the ability of specific T cells to enrich in the bone marrow.

Oncolytic Virus Engineering and Utilizations: Cancer Immunotherapy Perspective

Oncolytic viruses have positively impacted cancer immunotherapy over the past 20 years. Both natural and genetically modified viruses have shown promising results in treating various cancers. Various regulatory authorities worldwide have approved four commercial oncolytic viruses, and more are being developed to overcome this limitation and obtain better anti-tumor responses in clinical trials at various stages. Faster advancements in translating research into the commercialization of cancer immunotherapy and a comprehensive understanding of the modification strategies will widen the current knowledge of future technologies related to the development of oncolytic viruses. In this review, we discuss the strategies of virus engineering and the progress of clinical trials to achieve virotherapeutics.

New genetic and epigenetic insights into the chemokine system: the latest discoveries aiding progression toward precision medicine

Over the past thirty years, the importance of chemokines and their seven-transmembrane G protein-coupled receptors (GPCRs) has been increasingly recognized. Chemokine interactions with receptors trigger signaling pathway activity to form a network fundamental to diverse immune processes, including host homeostasis and responses to disease. Genetic and nongenetic regulation of both the expression and structure of chemokines and receptors conveys chemokine functional heterogeneity. Imbalances and defects in the system contribute to the pathogenesis of a variety of diseases, including cancer, immune and inflammatory diseases, and metabolic and neurological disorders, which render the system a focus of studies aiming to discover therapies and important biomarkers. The integrated view of chemokine biology underpinning divergence and plasticity has provided insights into immune dysfunction in disease states, including, among others, coronavirus disease 2019 (COVID-19). In this review, by reporting the latest advances in chemokine biology and results from analyses of a plethora of sequencing-based datasets, we outline recent advances in the understanding of the genetic variations and nongenetic heterogeneity of chemokines and receptors and provide an updated view of their contribution to the pathophysiological network, focusing on chemokine-mediated inflammation and cancer. Clarification of the molecular basis of dynamic chemokine-receptor interactions will help advance the understanding of chemokine biology to achieve precision medicine application in the clinic.

Combining energy-based focal ablation and immune checkpoint inhibitors: preclinical research and clinical trials

Energy-based focal therapy (FT) uses targeted, minimally invasive procedures to destroy tumors while preserving normal tissue and function. There is strong emerging interest in understanding how systemic immunity against the tumor can occur with cancer immunotherapy, most notably immune checkpoint inhibitors (ICI). The motivation for combining FT and ICI in cancer management relies on the synergy between the two different therapies: FT complements ICI by reducing tumor burden, increasing objective response rate, and reducing side effects of ICI; ICI supplements FT by reducing local recurrence, controlling distal metastases, and providing long-term protection. This combinatorial strategy has shown promising results in preclinical study (since 2004) and the clinical trials (since 2011). Understanding the synergy calls for understanding the physics and biology behind the two different therapies with distinctive mechanisms of action. In this review, we introduce different types of energy-based FT by covering the biophysics of tissue-energy interaction and present the immunomodulatory properties of FT. We discuss the basis of cancer immunotherapy with the emphasis on ICI. We examine the approaches researchers have been using and the results from both preclinical models and clinical trials from our exhaustive literature research. Finally, the challenges of the combinatory strategy and opportunities of future research is discussed extensively.

Regulation of CD8+ T cells infiltration and immunotherapy by circMGA/HNRNPL complex in bladder cancer

The limited success of immunotherapies targeting immune checkpoint inhibitors is largely ascribed to the lack of infiltrating CD8+ T lymphocytes. Circular RNAs (circRNAs) are a novel type of prevalent noncoding RNA that have been implicated in tumorigenesis and progression, while their roles in modulating CD8+ T cells infiltration and immunotherapy in bladder cancer have not yet been investigated. Herein, we uncover circMGA as a tumor-suppressing circRNA triggering CD8+ T cells chemoattraction and boosting the immunotherapy efficacy. Mechanistically, circMGA functions to stabilize CCL5 mRNA by interacting with HNRNPL. In turn, HNRNPL increases the stability of circMGA, forming a feedback loop that enhances the function of circMGA/HNRNPL complex. Intriguingly, therapeutic synergy between circMGA and anti-PD-1 could significantly suppress xenograft bladder cancer growth. Taken together, the results demonstrate that circMGA/HNRNPL complex may be targetable for cancer immunotherapy and the study advances our understanding of the physiological roles of circRNAs in antitumor immunity.

Tumor-targeted superantigens produce curative tumor immunity with induction of memory and demonstrated antigen spreading

BACKGROUND

Despite remarkable progress, the immunotherapies currently used in the clinic, such as immune checkpoint blockade (ICB) therapy, still have limited efficacy against many types of solid tumors. One major barrier to effective treatment is the lack of a durable long-term response. Tumor-targeted superantigen (TTS) therapy may overcome this barrier to enhance therapeutic efficacy. TTS proteins, such as the clinical-stage molecule naptumomab estafenatox (NAP), increase tumor recognition and killing by both coating tumor cells with bacterial-derived superantigens (SAgs) and selectively expanding T-cell lineages that can recognize them. The present study investigated the efficacy and mechanism of action of repeated TTS (C215Fab-SEA) treatments leading to a long-term antitumor immune response as monotherapy or in combination with PD-1/PD-L1 inhibitors in murine tumor models.

METHODS

We used syngeneic murine tumor models expressing the human EpCAM target (C215 antigen) to assess the efficacy and mechanism of action of repeated treatment with TTS C215Fab-SEA alone or with anti-PD-1/PD-L1 monoclonal antibodies. Tumor draining lymph nodes (TDLNs) and tumor tissues were processed and analyzed by immunophenotyping and immunohistochemistry. Isolated RNA from tumors was used to analyze gene expression and the TCR repertoire. Tumor rechallenge and T-cell transfer studies were conducted to test the long-term antitumor memory response.

RESULTS

TTS therapy inhibited tumor growth and achieved complete tumor rejection, leading to a T-cell-dependent long-term memory response against the tumor. The antitumor effect was derived from inflammatory responses converting the immunosuppressive TME into a proinflammatory state with an increase in T-cell infiltration, activation and high T-cell diversity. The combination of TTS with ICB therapy was significantly more effective than the monotherapies and resulted in higher tumor-free rates.

CONCLUSIONS

These new results indicate that TTSs not only can turn a "cold" tumor into a "hot" tumor but also can enable epitope spreading and memory response, which makes TTSs ideal candidates for combination with ICB agents and other anticancer agents.

Using mouse liver cancer models based on somatic genome editing to predict immune checkpoint inhibitor responses

BACKGROUND & AIMS

Tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (ICIs) are the only two classes of FDA-approved drugs for individuals with advanced hepatocellular carcinoma (HCC). While TKIs confer only modest survival benefits, ICIs have been associated with remarkable outcomes but only in the minority of patients who respond. Understanding the mechanisms that determine the efficacy of ICIs in HCC will help to stratify patients likely to respond to ICIs. This study aims to elucidate how genetic composition and specific oncogenic pathways regulate the immune composition of HCC, which directly affects response to ICIs.

METHODS

A collection of mouse HCCs with genotypes that closely simulate the genetic composition found in human HCCs were established using genome-editing approaches involving the delivery of transposon and CRISPR-Cas9 systems by hydrodynamic tail vein injection. Mouse HCC tumors were analyzed by RNA-sequencing while tumor-infiltrating T cells were analyzed by flow cytometry and single-cell RNA-sequencing.

RESULTS

Based on the CD8⁺ T cell-infiltration level, we characterized tumors with different genotypes into cold and hot tumors. Anti-PD-1 treatment had no effect in cold tumors but was greatly effective in hot tumors. As proof-of-concept, a cold tumor (Trp53^KO/MYC^OE) and a hot tumor (Keap1^KO/MYC^OE) were further characterized. Tumor-infiltrating CD8⁺ T cells from Keap1^KO/MYC^OE HCCs expressed higher levels of proinflammatory chemokines and exhibited enrichment of a progenitor exhausted CD8⁺ T-cell phenotype compared to those in Trp53^KO/MYC^OE HCCs. The TKI sorafenib sensitized Trp53^KO/MYC^OE HCCs to anti-PD-1 treatment.

CONCLUSION

Single anti-PD-1 treatment appears to be effective in HCCs with genetic mutations driving hot tumors, while combined anti-PD-1 and sorafenib treatment may be more appropriate in HCCs with genetic mutations driving cold tumors.

IMPACT AND IMPLICATIONS

Genetic alterations of different driver genes in mouse liver cancers are associated with tumor-infiltrating CD8⁺ T cells and anti-PD-1 response. Mouse HCCs with different genetic compositions can be grouped into hot and cold tumors based on the level of tumor-infiltrating CD8⁺ T cells. This study provides proof-of-concept evidence to show that hot tumors are responsive to anti-PD-1 treatment while cold tumors are more suitable for combined treatment with anti-PD-1 and sorafenib. Our study might help to guide the design of patient stratification systems for single or combined treatments involving anti-PD-1.

Mechanisms of primary and acquired resistance to immune checkpoint inhibitors in advanced non-small cell lung cancer: A multiplex immunohistochemistry-based single-cell analysis

OBJECTIVE

Immune checkpoint inhibitors (ICIs) have become a key therapeutic modality for advanced non-small cell lung cancer (NSCLC), but most patients experience primary or acquired resistance to these drugs. We here explored the mechanisms underlying both types of ICI resistance by analysis of the tumor immune microenvironment (TME).

MATERIALS AND METHODS

Four patients who experienced a long-term response to ICI treatment (progression-free survival [PFS] of ≥12 months) followed by disease progression, after which a rebiopsy was immediately performed (cohort-A), as well as four patients who experienced early tumor progression during ICI treatment (PFS of <9 weeks, cohort-B) were enrolled in this retrospective study. The pretreatment TME was evaluated by 16- or 17-color multiplex immunohistochemistry (mIHC)-based spatial profiling at the single-cell level for both cohorts. In cohort-A, changes in the TME after disease progression during ICI treatment were also investigated by mIHC analysis and transcriptomic analysis.

RESULTS

Pretreatment tumor tissue from cohort-B manifested poor infiltration of tumor-reactive CD8⁺ T cells characterized by CD39 and CD103 expression or by programmed cell death-1 expression, implicating insufficient recognition of tumor cells by CD8⁺ T cells as a mechanism of primary ICI resistance. Analysis of the paired tumor specimens from cohort-A revealed various changes in the TME associated with acquired ICI resistance, including substantial infiltration of myeloid-derived suppressor cells and M2-type tumor-associated macrophages without a marked decline in the number of tumor-reactive CD8⁺ T cells; a decrease in the number of tumor-reactive CD8⁺ T cells; and an apparent decrease in neoantigen presentation by tumor cells.

CONCLUSION

The presence of intratumoral tumor-reactive CD8⁺ T cells may be a prerequisite for a long-term response to ICI treatment in advanced NSCLC, but it is not sufficient for cancer cell eradication. Various TME profiles are associated with acquired ICI resistance, suggesting that patient-specific strategies to overcome such resistance may be necessary.

Continuous sensing of IFNα by hepatic endothelial cells shapes a vascular antimetastatic barrier

Hepatic metastases are a poor prognostic factor of colorectal carcinoma (CRC) and new strategies to reduce the risk of liver CRC colonization are highly needed. Herein, we used mouse models of hepatic metastatization to demonstrate that the continuous infusion of therapeutic doses of interferon-alpha (IFNα) controls CRC invasion by acting on hepatic endothelial cells (HECs). Mechanistically, IFNα promoted the development of a vascular antimetastatic niche characterized by liver sinusoidal endothelial cells (LSECs) defenestration extracellular matrix and glycocalyx deposition, thus strengthening the liver vascular barrier impairing CRC trans-sinusoidal migration, without requiring a direct action on tumor cells, hepatic stellate cells, hepatocytes, or liver dendritic cells (DCs), Kupffer cells (KCs) and liver capsular macrophages (LCMs). Moreover, IFNα endowed LSECs with efficient cross-priming potential that, along with the early intravascular tumor burden reduction, supported the generation of antitumor CD8+ T cells and ultimately led to the establishment of a protective long-term memory T cell response. These findings provide a rationale for the use of continuous IFNα therapy in perioperative settings to reduce CRC metastatic spreading to the liver.

Bispecific Antibodies in Cancer Immunotherapy: A Novel Response to an Old Question

Immunotherapy has redefined the treatment of cancer patients and it is constantly generating new advances and approaches. Among the multiple options of immunotherapy, bispecific antibodies (bsAbs) represent a novel thoughtful approach. These drugs integrate the action of the immune system in a strategy to redirect the activation of innate and adaptive immunity toward specific antigens and specific tumor locations. Here we discussed some basic aspects of the design and function of bsAbs, their main challenges and the state-of-the-art of these molecules in the treatment of hematological and solid malignancies and future perspectives.

Viral coinfection promotes tuberculosis immunopathogenesis by type I IFN signaling-dependent impediment of Th1 cell pulmonary influx

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), is often exacerbated upon coinfection, but the underlying immunological mechanisms remain unclear. Here, to elucidate these mechanisms, we use an Mtb and lymphocytic choriomeningitis virus coinfection model. Viral coinfection significantly suppresses Mtb-specific IFN-γ production, with elevated bacterial loads and hyperinflammation in the lungs. Type I IFN signaling blockade rescues the Mtb-specific IFN-γ response and ameliorates lung immunopathology. Single-cell sequencing, tissue immunofluorescence staining, and adoptive transfer experiments indicate that viral infection-induced type I IFN signaling could inhibit CXCL9/10 production in myeloid cells, ultimately impairing pulmonary migration of Mtb-specific CD4⁺ T cells. Thus, our study suggests that augmented and sustained type I IFNs by virus coinfection prior to the pulmonary localization of Mtb-specific Th1 cells exacerbates TB immunopathogenesis by impeding the Mtb-specific Th1 cell influx. Our study highlights a negative function of viral coinfection-induced type I IFN responses in delaying Mtb-specific Th1 responses in the lung.

Viral coinfection alongside mycobacterium tuberculosis (Mtb) infection may lead to immune complications or interference with immune responses. Here the authors show that in mice infected with Mtb and LCMV virus the specific T_H1 response to MTb is reduced through a type I IFN response to the infecting virus.

Exploring Tumor Immune Microenvironment and Its Associations With Molecular Characteristics in Melanoma

Background

The tumor microenvironment (TME), which involves infiltration of multiple immune cells into the tumor tissues, plays an essential role in clinical benefit to therapy. The chemokines and their receptors influence migration and functions of both tumor and immune cells. Also, molecular characteristics are associated with the efficacy of melanoma therapy. However, there lacked exploration of immune characteristics and the association with molecular characteristics.

Methods

We collected the currently available 569 melanoma samples that had both the genomic and transcriptional data from TCGA and SRA databases. We first identified TME subtypes based on the developed immune signatures, and then divided the samples into two immune cohorts based on the immune score. Next, we estimated the compositions of the immune cells of the two cohorts, and performed differential expression genes (DEGs) and functional enrichments. In addition, we investigated the interactions of chemokines and their receptors under immune cells. Finally, we explored the genomic characteristics under different immune subtypes.

Results

TME type D had a better prognosis among the four subtypes. The high-immunity cohort had significantly high 16 immune cells. The 63 upregulated and 384 downregulated genes in the high-immunity cohort were enriched in immune-related biological processes, and keratin, pigmentation and epithelial cells, respectively. The correlations of chemokines and their receptors with immune cell infiltration, such as CCR5-CCL4/CCL5 and CXCR3-CXCL9/CXCL10/CXCL11/CXCL13 axis, showed that the recruitments of 11 immune cells, such as CD4T cells and CD8T cells, were modulated by chemokines and their receptors. The proportions of the four TME subtypes in each molecular subtype were comparable. The two driver genes, CDKN2A and PRB2, had significantly different MAFs between the high-immunity and low-immunity.

Conclusion

We dissected the characteristics of immune infiltration, the interactions of chemokines and their receptors under immune cells, and the correlation of molecular and immune characteristics. Our work will enable the reasonable selection of anti-melanoma treatments and accelerate the development of new therapeutic strategies for melanoma.

Protective effects of glycine against lipopolysaccharide-induced intestinal apoptosis and inflammation

Intestinal dysfunction is commonly observed in humans and animals. Glycine (Gly) is a functional amino acid with anti-inflammatory and anti-apoptotic properties. The objective of this study was to test the protective effects of Gly against lipopolysaccharide (LPS)-induced intestinal injury. 28 C57BL/6 mice with a body weight (BW) of 18 ± 2 g were randomly assigned into four groups: CON (control), GLY (orally administered Gly, 5 g/kg BW/day for 6 days), LPS (5 mg/kg BW on day 7, i. p.), and GLY + LPS (Gly pretreatment and LPS administration). Histological alterations, inflammatory responses, epithelial cell apoptosis, and changes of the intestinal microbiota were analyzed. Results showed that, compared with the CON group, mice in the LPS treatment group showed decreased villus height, increased crypt depth, and decreased ratio of villus height to crypt depth, which were significantly attenuated by Gly. Neither LPS nor Gly treatment altered morphology of the distal colon tissues. LPS increased the apoptosis of jejunum and colon epithelial cells and protein abundance of cleaved caspase3 in the jejunum, which were markedly abrogated by Gly. LPS also elevated the mRNA levels of Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MYD88), pro-inflammatory cytokines, and chemokines in the jejunum and colon. These alterations were significantly suppressed by Gly. In addition, Gly supplementation attenuated infiltration of CD4+, CD8+ T-lymphocytes, CD11b+ and F4/80+ macrophages in the colon. Furthermore, Gly increased the relative abundance of Mucispirillum, Lachnospiraceae-NK4A136-group, Anaerotruncus, Faecalibaculum, Ruminococcaceae-UCG-014, and decreased the abundance of Bacteroides at genus level. Supplementation with Gly might be a nutritional strategy to ameliorate LPS-induced intestinal injury in mice.

Hyperuricemia induces lipid disturbances by upregulating the CXCL-13 pathway

The molecular mechanism underlying hyperuricemia-induced lipid metabolism disorders is not clear. The purpose of the current study was to investigate the mechanism of lipid disturbances in a hyperuricemia mice model. RNA-Seq showed that differentially expressed genes (DEGs) in the fatty acid synthesis signaling pathway were mainly enriched and CXCL-13 was significantly enriched in protein-protein interaction networks. Western blotting, Q-PCR, and immunofluorescence results further showed that hyperuricemia upregulated CXCL-13 and disturbed lipid metabolism in vivo and in vitro. Furthermore, CXCL-13 alone also promoted the accumulation of lipid droplets and upregulated the expression of FAS and SREBP1, blocking AMPK signaling and activating the PKC and P38 signaling pathways. Silencing CXCL-13 reversed uric-acid-induced lipid droplet accumulation, which further downregulated FAS and SREBP1 expression, inhibited the p38 and PKC signaling, and activated AMPK signaling. In conclusion, hyperuricemia induces lipid metabolism disorders via the CXCL-13 pathway, making CXCL-13 a key regulatory factor linking hyperuricemia and lipid metabolism disorders. These results may provide novel insights for the treatment of hyperuricemia.NEW & NOTEWORTHY The underlying molecular mechanism of hyperuricemia-induced lipid metabolism disorders is still unclear. The study aimed to investigate the mechanism of lipid disturbance in hyperuricemia mice model. To our knowledge, we proposed for the first time that CXCL-13 may be a key regulator of hyperuricemia and lipid metabolism disorders. These results may provide new insights for the clinical treatment of hyperuricemia.

Associations of CXCL12 polymorphisms with clinicopathological features in breast cancer: a case-control study

Background

Previous studies suggested that CXCL12 was involved in the development, metastasis, and invasion of breast cancer, and genetic variants were associated with the diagnosis and prognosis of patients with breast cancer. The present study was aimed to assess the relationships between CXCL12 polymorphisms (rs1801157, rs2297630, and rs2839693) and susceptibility and clinicopathological features of breast cancer.

Methods

A case-control study was conducted in 434 breast cancer patients and 450 health controls. Student t-test and chi-square test were used to analyze the differences of age distribution and genotype frequencies between the two groups. Correlations between polymorphisms and clinical parameters were also assessed by chi-square test. The potential effects of the three polymorphisms on CXCL12 were investigated by the public database.

Results

A statistical association was found between CXCL12 rs1801157 polymorphism and breast cancer risk, possibility of metastasis, and estrogen receptor status. Patients with rs2839693 C/T or C/T-T/T genotypes were more likely to be progesterone receptor-negative. However, no associations of rs2297630 polymorphism with breast cancer risk or any clinicopathological characteristics were observed. In addition, rs2297630 affected the splicing quantitative trait loci of CXCL12 in the subcutaneous fat, rs2839693 polymorphism affected the splicing quantitative trait loci of CXCL12 in the human breast mammary tissues.

Conclusions

Those results indicated that CXCL12 polymorphisms might be potential diagnostic indicators, and more investigation is needed in the future.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11033-021-07047-9.

GPR182 limits antitumor immunity via chemokine scavenging in mouse melanoma models

For many solid tumors, immune checkpoint blockade therapy has become first line treatment, yet a large proportion of patients with immunologically cold tumors do not benefit due to the paucity of tumor infiltrating lymphocytes. Here we show that the orphan G Protein-Coupled Receptor 182 (GPR182) contributes to immunotherapy resistance in cancer via scavenging chemokines that are important for lymphocyte recruitment to tumors. GPR182 is primarily upregulated in melanoma-associated lymphatic endothelial cells (LECs) during tumorigenesis, and this atypical chemokine receptor endocytoses chemokines promiscuously. In GPR182-deficient mice, T cell infiltration into transplanted melanomas increases, leading to enhanced effector T cell function and improved antitumor immunity. Ablation of GPR182 leads to increased intratumoral concentrations of multiple chemokines and thereby sensitizes poorly immunogenic tumors to immune checkpoint blockade and adoptive cellular therapies. CXCR3 blockade reverses the improved antitumor immunity and T cell infiltration characteristic of GPR182-deficient mice. Our study thus identifies GPR182 as an upstream regulator of the CXCL9/CXCL10/CXCR3 axis that limits antitumor immunity and as a potential therapeutic target in immunologically cold tumors.

Immunologically cold tumours don’t respond to immune checkpoint blockade inhibition due to poor recruitment of anti-tumour T cells. Authors show here that melanoma-associated lymphatic endothelial cells express G Protein-Coupled Receptor 182 that scavenges CXCL9 and other chemokines necessary for T cell recruitment.

Potential Role of CXCL13/CXCR5 Signaling in Immune Checkpoint Inhibitor Treatment in Cancer

Simple Summary

Immunotherapy is currently the backbone of new drug treatments for many cancer patients. CXC chemokine ligand 13 (CXCL13) is an important factor involved in recruiting immune cells that express CXC chemokine receptor type 5 (CXCR5) in the tumor microenvironment and serves as a key molecular determinant of tertiary lymphoid structure (TLS) formation. An increasing number of studies have identified the influence of CXCL13 on prognosis in patients with cancer, regardless of the use of immunotherapy treatment. However, no comprehensive reviews of the role of CXCL13 in cancer immunotherapy have been published to date. This review aims to provide an overview of the CXCL13/CXCR5 signaling axis to summarize its mechanisms of action in cancer cells and lymphocytes, in addition to effects on immunity and cancer pathobiology, and its potential as a biomarker for the response to cancer immunotherapy.

Abstract

Immune checkpoint inhibitors (ICIs), including antibodies that target programmed cell death protein 1 (PD-1), programmed death-ligand 1 (PD-L1), or cytotoxic T lymphocyte antigen 4 (CTLA4), represent some of the most important breakthroughs in new drug development for oncology therapy from the past decade. CXC chemokine ligand 13 (CXCL13) exclusively binds CXC chemokine receptor type 5 (CXCR5), which plays a critical role in immune cell recruitment and activation and the regulation of the adaptive immune response. CXCL13 is a key molecular determinant of the formation of tertiary lymphoid structures (TLSs), which are organized aggregates of T, B, and dendritic cells that participate in the adaptive antitumor immune response. CXCL13 may also serve as a prognostic and predictive factor, and the role played by CXCL13 in some ICI-responsive tumor types has gained intense interest. This review discusses how CXCL13/CXCR5 signaling modulates cancer and immune cells to promote lymphocyte infiltration, activation by tumor antigens, and differentiation to increase the antitumor immune response. We also summarize recent preclinical and clinical evidence regarding the ICI-therapeutic implications of targeting the CXCL13/CXCR5 axis and discuss the potential role of this signaling pathway in cancer immunotherapy.

Mechanisms of Antitumor Immunity and Immunosurveillance

The immune system has a well-defined role in all stages of carcinogenesis. The current chapter presents a discussion of various constituents of immunity involved in tumorigenesis along with their mechanisms, forming the basis for immunoprevention and immunotherapy.

Interleukin-8 in Melanoma Pathogenesis, Prognosis and Therapy-An Integrated View into Other Neoplasms and Chemokine Networks

Cutaneous melanoma accounts for only about 7% of skin cancers but is causing almost 90% of deaths. Melanoma cells have a distinct repertoire of mutations from other cancers, a high plasticity and degree of mimicry toward vascular phenotype, stemness markers, versatility in evading and suppress host immune control. They exert a significant influence on immune, endothelial and various stromal cells which form tumor microenvironment. The metastatic stage, the leading cause of mortality in this neoplasm, is the outcome of a complex, still poorly understood, cross-talk between tumor and other cell phenotypes. There is accumulating evidence that Interleukin-8 (IL-8) is emblematic for advanced melanomas. This work aimed to present an updated status of IL-8 in melanoma tumor cellular complexity, through a comprehensive analysis including data from other chemokines and neoplasms. The multiple processes and mechanisms surveyed here demonstrate that IL-8 operates following orchestrated programs within signaling webs in melanoma, stromal and vascular cells. Importantly, the yet unknown molecularity regulating IL-8 impact on cells of the immune system could be exploited to overturn tumor fate. The molecular and cellular targets of IL-8 should be brought into the attention of even more intense scientific exploration and valorization in the therapeutical management of melanoma.

Tumor-associated macrophages, dendritic cells, and neutrophils: biological roles, crosstalk, and therapeutic relevance

Tumor-associated myeloid cells constitute a series of plastic and heterogeneous cell populations within the tumor microenvironment (TME), and exhibit different phenotypes and functions in response to various microenvironmental signals. In light of promising preclinical data indicating that myeloid-based therapy can effectively suppress tumor growth, a series of novel immune-based therapies and approaches are currently undergoing clinical evaluation. A better understanding of the diversity and functional roles of different myeloid cell subtypes and of how they are associated with TME remodeling may help to improve cancer therapy. Herein, we focus on myeloid cells and discuss how tumor cells can simultaneously reprogram these cells through tumor-derived factors and metabolites. In addition, we discuss the interactions between myeloid cells and other cells in the TME that have the potential to directly or indirectly regulate tumor initiation, invasion, or angiogenesis. We further discuss the current and future potential applications of myeloid cells in the development of focused therapeutic strategies in cancer treatment.

Current trends of anti-cancer molecular targeted therapies: a narrative review focusing on renal complications and their histological features

Among the recent advancements in cancer treatment, the emergence of novel drugs targeting a specific molecule has considerably modulated the therapeutic strategies. Despite the efficacy, the associated renal complications distinct from conventional chemotherapeutic drugs have been reported. Targeted therapy drugs include monoclonal antibodies and small molecule agents. Bevacizumab is one of the monoclonal antibodies that targets vascular endothelial growth factor (VEGF) and blocks tumor angiogenesis. This anti-angiogenic effect causes endothelial injury, resulting in "thrombotic microangiopathy-like lesion" confined to the glomerulus. Segmental hyalinosis of the glomerular tuft is also observed. The small molecular agents, including tyrosine kinase inhibitors (TKIs), such as pazopanib, can cause endothelial injury and podocytopathy through blocking VEGF receptors and their downstream signaling. Minimal change nephrotic syndrome and focal segmental glomerulosclerosis are associated with TKIs-induced renal complications. Immune checkpoint inhibitors (ICIs), such as PD-1, CTLA-4 and PD-L1, are a novel form of immunotherapy against cancer, which modulates immune checkpoints. Owing to its unique function, ICIs cause inflammatory side effects referred to as immune-related adverse events (irAEs). irAEs in the kidney commonly include acute tubulointerstitial nephritis and tubulitis, occasionally accompanied by granuloma formation. The occurrence of vasculitis, thrombotic microangiopathy, and glomerulonephritis is also reported. Renal toxicity associated with other molecular drugs such as protease inhibitors and mammalian target of rapamycin inhibitors has also been documented. In this article, we review the clinico-histopathological aspects of renal complications associated with molecular targeted therapies, focusing on anti-VEGF agents and immune checkpoint inhibitors from the pathologists' viewpoint.

Rs7853346 Polymorphism in lncRNA-PTENP1 and rs1799864 Polymorphism in CCR2 are Associated with Radiotherapy-Induced Cognitive Impairment in Subjects with Glioma Via Regulating PTENP1/miR-19b/CCR2 Signaling Pathway

LncRNA-PTENP1 was reported to promote multiple myeloma cancer stem cell proliferation, and the G allele of rs7853346 polymorphism in lncRNA-PTENP1 was demonstrated to enhance the effect of lncRNA-PTENP1. In this study, we aimed to study the potential effect of lncRNA-PTENP1 and CCR2 mRNA polymorphisms on cognitive impairment in glioma patients. In this study, 279 glioma patients were recruited and grouped according to their genotypes of rs7853346 in PTENP1 and rs1799864 in CCR1. Pathogenic parameters were collected from patients before radiotherapy (month 0) or at month 1 and month 3 after radiotherapy to study the effect of rs7853346 and rs1799864 on cognitive impairment. Sequence analysis, luciferase assay, real-time PCR, and Western blot were performed to study the regulatory relationships between lncRNA-PTENP1, miR-18b, and CCR2. The glioma patient groups exhibited no significant differences concerning basic characteristics. However, the CG&GG/GG genotype alleviated radiotherapy-induced cognitive impairment by exhibiting the highest MMSE among the four groups. On the contrary, parameters including the severity of depression, bladder control, global health status, itchy skin, and weakness of legs all showed no difference among different patient groups at month 0, month 1, and month 3. Also, a long-term positive effect of CG&GG/GG genotype on role functioning and social functioning was also observed after radiotherapy. Compared with patients carrying the CC genotype of rs7853346, the expression of lncRNA-PTENP1 was reduced while the miR-19b level was elevated in patients carrying the CG&GG genotypes of rs7853346. Moreover, the expression of CCR2 mRNA was the highest in the CC/GA&AA group and the lowest in the CG&GG/GG group. Subsequent sequence analysis and luciferase assay indicated that miR-19b could bind to lncRNA-PTENP1 and 3'UTR of CCR2 mRNA, and the knockdown of lncRNA-PTENP1 led to evident up-regulation of miR-19b and down-regulation of CCR2 mRNA/protein in a cellular model, thus verifying the presence of the lncRNA-PTENP1/miR-19b/CCR2 mRNA signaling pathway. In conclusion, by studying the changes in the key parameters of glioma patients who were subjected to radiotherapy, we concluded that the rs7853346 polymorphism in lncRNA-PTENP1 and the rs1799864 polymorphism in CCR2 could independently affect cognitive impairment, while a more significant combined effect on cognitive impairment was exerted in glioma patients via the signaling pathway of PTENP1/miR-19b/CCR2.

T Cell Bispecific Antibodies: An Antibody-Based Delivery System for Inducing Antitumor Immunity

As a breakthrough immunotherapy, T cell bispecific antibodies (T-BsAbs) are a promising antibody therapy for various kinds of cancer. In general, T-BsAbs have dual-binding specificity to a tumor-associated antigen and a CD3 subunit forming a complex with the TCR. This enables T-BsAbs to crosslink tumor cells and T cells, inducing T cell activation and subsequent tumor cell death. Unlike immune checkpoint inhibitors, which release the brake of the immune system, T-BsAbs serve as an accelerator of T cells by stimulating their immune response via CD3 engagement. Therefore, they can actively redirect host immunity toward tumors, including T cell recruitment from the periphery to the tumor site and immunological synapse formation between tumor cells and T cells. Although the low immunogenicity of solid tumors increases the challenge of cancer immunotherapy, T-BsAbs capable of immune redirection can greatly benefit patients with such tumors. To investigate the detailed relationship between T-BsAbs delivery and their T cell redirection activity, it is necessary to determine how T-BsAbs deliver antitumor immunity to the tumor site and bring about tumor cell death. This review article discusses T-BsAb properties, specifically their pharmacokinetics, redirection of anticancer immunity, and local mechanism of action within tumor tissues, and discuss further challenges to expediting T-BsAb development.

Large tumor suppressor 2 is a prognostic biomarker and correlated with immune infiltrates in colorectal cancer

Colorectal cancer (CRC) is a common malignancy that has both low 5-year survival and high prevalence. Immunotherapy has achieved impressive progress for treatment of CRC, but still faces huge challenges. Although large tumor suppressor 2 (LATS2) is well accepted to be related to cancer progression, the prognostic potential and immune response role of LATS2 expression in CRC remain unclear. To investigate the value of LATS2 for prognosis and immune infiltration, a retrospective study of 213 CRC patients was carried out. We determined the expression of LATS2 in tumor tissues by immunohistochemistry. The results indicated that LATS2 expression was down-regulated in CRC tissues and clearly related to tumor differentiation (P = 0.002) and TNM stage (P = 0.002). Low LATS2 expression and TNM stage were subsequently identified as significant independent predictors of prognosis in CRC by univariate and multivariate analyses. In Kaplan–Meier survival analyses, CRC patients with elevated LATS2 expression and early TNM stage had better overall survival. We further found that LATS2 was involved in the regulation of immune-related pathways and that its expression was positively related to tumor-infiltrating immune cells by GSEA, TIMER, and ssGSEA analyses. In summary, our data imply that LATS2 may act as a cancer suppressor gene and be correlated with clinical prognosis and immune infiltration in CRC. Thus, LATS2 may be applied as a novel biomarker for predicting clinical outcomes and immune infiltration levels in CRC.

Immunotherapy in Recurrent/Metastatic Squamous Cell Carcinoma of the Head and Neck

Head and neck cancer is the 6^th most common cancer worldwide with the most common histology being squamous cell carcinoma (HNSCC). While the majority of patients present at a stage where curative intent therapy is possible, when patients recur and/or develop metastatic disease, outcomes are generally poor, especially with systemic therapy alone, and they lag behind other solid tumors. Over the last decade immunotherapy has revolutionized the field of oncology, and anti-PD-1-based therapy has changed the standard of care in recurrent/metastatic (R/M) HNSCC as well. With these gains have come new questions to continue to move the field forward. In this review, we discuss the tumor immune microenvironment and predictive biomarkers and current status and future directions for immunotherapy in recurrent/metastatic head and neck cancer.

Chemokine-targeted therapies: An opportunity to remodel immune profiles in gastro-oesophageal tumours

Immunotherapies are transforming outcomes for many cancer patients and are quickly becoming the fourth pillar of cancer therapy. However, their efficacy of only ∼25% in gastro-oesophageal cancer has been disappointing. This is attributed to factors such as insufficient patient stratification and the pro-tumourigenic immune landscape of gastro-oesophageal tumours. The chemokine profiles of solid tumours and the availability of effector immune cells greatly influence the immune infiltrate, producing 'cold' or 'immune-excluded' tumours in which immunotherapies are unable to reinvigorate the immune response. Other biological functions for chemokines have emerged, such as promoting cell survival, polarising T cell responses, and supporting several hallmarks of cancer. Therefore, chemokine networks may be exploited with therapeutic intent to mobilise and polarise anti-tumour immune cells, with further utility as combination treatments to augment the efficacy of current cancer immunotherapies. Few studies have demonstrated the clinical benefit of chemokine-targeted therapies as monotherapies, and this review proposes their consideration as combination treatments. Herein, we explore the anti-tumour and pro-tumour implications of chemokine signalling in gastro-oesophageal cancer and discuss their value as prognostic and predictive biomarkers in response to treatment.

Immune Checkpoint Inhibitors Mediated Lymphocytic and Giant Cell Myocarditis: Uncovering Etiological Mechanisms

The advent of immune checkpoint inhibitors (ICIs) has revolutionized the field of oncology, but these are associated with immune related adverse events. One such adverse event, is myocarditis, which has limited the continued immunosuppressive treatment options in patients afflicted by the disease. Pre-clinical and clinical data have found that specific ICI targets and precipitate distinct myocardial infiltrates, consistent with lymphocytic or giant cell myocarditis. Specifically, it has been reported that CTLA-4 inhibition preferentially results in giant cell myocarditis with a predominately CD4+ T cell infiltrate and PD-1 inhibition leads to lymphocytic myocarditis, with a predominately CD8+ T cell infiltrate. Our manuscript discusses the latest literature surrounding ICI pathways and targets, while detailing proposed mechanisms behind ICI mediated myocarditis.

Effects of 1p/19q Codeletion on Immune Phenotype in Low Grade Glioma

Background: Chromosome 1p/19q codeletion is one of the most important genetic alterations for low grade gliomas (LGGs), and patients with 1p/19q codeletion have significantly prolonged survival compared to those without the codeletion. And the tumor immune microenvironment also plays a vital role in the tumor progression and prognosis. However, the effect of 1p/19q codeletion on the tumor immune microenvironment in LGGs is unclear. Methods: Immune cell infiltration of 281 LGGs from The Cancer Genome Atlas (TCGA) and 543 LGGs from the Chinese Glioma Genome Atlas (CGGA) were analyzed for immune cell infiltration through three bioinformatics tools: ESTIMATE algorithm, TIMER, and xCell. The infiltrating level of immune cells and expression of immune checkpoint genes were compared between different groups classified by 1p/19q codeletion and IDH (isocitrate dehydrogenase) mutation status. The differential biological processes and signaling pathways were evaluated through Gene Set Enrichment Analysis (GSEA). Correlations were analyzed using Spearman correlation. Results: 1p/19q codeletion was associated with immune-related biological processes in LGGs. The infiltrating level of multiple kinds of immune cells and expression of immune checkpoint genes were significantly lower in 1p/19q codeletion LGGs compared to 1p/19q non-codeletion cohorts. There are 127 immune-related genes on chromosome 1p or 19q, such as TGFB1, JAK1, and CSF1. The mRNA expression of these genes was positively correlated with their DNA copy number. These genes are distributed in multiple immune categories, such as chemokines/cytokines, TGF-β family members, and TNF family members, regulating immune cell infiltration and expression of the immune checkpoint genes in tumors. Conclusion: Our results indicated that 1p/19q codeletion status is closely associated with the immunosuppressive microenvironment in LGGs. LGGs with 1p/19q codeletion display less immune cell infiltration and lower expression of immune checkpoint genes than 1p/19q non-codeletion cases. Mechanistically, this may be, at least in part, due to the deletion of copy number of immune-related genes in LGGs with 1p/19q codeletion. Our findings may be relevant to investigate immune evasion in LGGs and contribute to the design of immunotherapeutic strategies for patients with LGGs.

Targeting regulator of G protein signaling 1 in tumor-specific T cells enhances their trafficking to breast cancer

Reduced infiltration of anti-tumor lymphocytes remains a major cause of tumor immune evasion and is correlated with poor cancer survival. Here, we found that upregulation of regulator of G protein signaling (RGS)1 in helper TH1 cells and cytotoxic T lymphocytes (CTLs) reduced their trafficking to and survival in tumors and was associated with shorter survival of patients with breast and lung cancer. RGS1 was upregulated by type II interferon (IFN)-signal transducer and activator of transcription (STAT)1 signaling and impaired trafficking of circulating T cells to tumors by inhibiting calcium influx and suppressing activation of the kinases ERK and AKT. RGS1 knockdown in adoptively transferred tumor-specific CTLs significantly increased their infiltration and survival in breast and lung tumor grafts and effectively inhibited tumor growth in vivo, which was further improved when combined with programmed death ligand (PD-L)1 checkpoint inhibition. Our findings reveal RGS1 is important for tumor immune evasion and suggest that targeting RGS1 may provide a new strategy for tumor immunotherapy.

CX3CL1 Overexpression Prevents the Formation of Lung Metastases in Trastuzumab-Treated MDA-MB-453-Based Humanized Tumor Mice (HTM)

Simple Summary

In about 15–18% of breast cancers the HER2 gene is amplified, which allows an anti-HER2 treatment. However, about 50% of HER2-positive patients experience de novo or acquired resistance to the antibody-based therapy with trastuzumab. Therefore, the identification of predictive markers for therapy success and novel combination strategies is needed. Here we explored the impact of CX3CL1 on trastuzumab treatment efficiency and immunological mechanism involved in a humanized tumor mouse model. Trastuzumab treatment showed pronounced efficiency in CX3CL1 overexpressing cancer cells compared to low expressing cells preventing lung metastasis, while the administration of CX3CL1 shedding inhibition did not cause an enhanced treatment effect. Moreover, the application of shedding inhibitors to CX3CL1 overexpression tumors resulted in a slightly enhanced tumor growth. Therefore, the presence of CX3CL1 might predict a pronounced response to trastuzumab therapy in patients and should be investigated in a large cohort of HER2⁺ patients.

Abstract

CX3CL1 is a multifunctional chemokine that is involved in numerous biological processes, such as immune cell attraction and enhanced tumor immune cell interaction, but also in enhancing tumor cell proliferation and metastasis. The multifarious activity is partially determined by two CX3CL1 isoforms, a membrane-bound and a soluble version generated by proteolytic cleavage through proteases. Here, we investigated the impact of CX3CL1 overexpression in MDA-MB-453 and SK-BR-3 breast cancer cells. Moreover, we evaluated the therapeutic capacity of Matrix-Metalloproteinases-inhibitors TMI-1 and GI254023X in combination with the anti-HER2 antibody trastuzumab in vitro and in vivo. TMI-1 and GI254023X caused a reduced shedding of CX3CL1 and of HER2 in vitro but without effects on tumor cell proliferation or viability. In addition, trastuzumab treatment did not retard MDA-MB-453 cell expansion in vitro unless CX3CL1 was overexpressed upon transfection (MDA-MB-453^CX3CL1). In humanized tumor mice, which show a coexistence of human tumor and human immune system, CX3CL1 overexpression resulted in a slightly enhanced tumor growth. However, trastuzumab treatment attenuated tumor growth of both MDA-MB-453^CX3CL1 and empty vector transfected MDA-MB-453 transplanted mice but showed enhanced efficiency especially in preventing lung metastases in CX3CL1 overexpressing cancer cells. However, TMI-1 did not further enhance the trastuzumab treatment efficacy.

CXCR4 and CXCR7 Signaling Pathways: A Focus on the Cross-Talk Between Cancer Cells and Tumor Microenvironment

The chemokine receptor 4 (CXCR4) and 7 (CXCR7) are G-protein-coupled receptors (GPCRs) activated through their shared ligand CXCL12 in multiple human cancers. They play a key role in the tumor/tumor microenvironment (TME) promoting tumor progression, targeting cell proliferation and migration, while orchestrating the recruitment of immune and stromal cells within the TME. CXCL12 excludes T cells from TME through a concentration gradient that inhibits immunoactive cells access and promotes tumor vascularization. Thus, dual CXCR4/CXCR7 inhibition will target different cancer components. CXCR4/CXCR7 antagonism should prevent the development of metastases by interfering with tumor cell growth, migration and chemotaxis and favoring the frequency of T cells in TME. Herein, we discuss the current understanding on the role of CXCL12/CXCR4/CXCR7 cross-talk in tumor progression and immune cells recruitment providing support for a combined CXCR4/CXCR7 targeting therapy. In addition, we consider emerging approaches that coordinately target both immune checkpoints and CXCL12/CXCR4/CXCR7 axis.

Enhancing clinical and immunological effects of anti-PD-1 with belapectin, a galectin-3 inhibitor

BACKGROUND

PD-1/PD-L1 engagement and overexpression of galectin-3 (Gal-3) are critical mechanisms of tumor-induced immune suppression that contribute to immunotherapy resistance. We hypothesized that Gal-3 blockade with belapectin (GR-MD-02) plus anti-PD-1 (pembrolizumab) would enhance tumor response in patients with metastatic melanoma (MM) and head and neck squamous cell carcinoma (HNSCC).

METHODS

We performed a phase I dose escalation study of belapectin+pembrolizumab in patients with advanced MM or HNSCC (NCT02575404). Belapectin was administered at 2, 4, or 8 mg/kg IV 60 min before pembrolizumab (200 mg IV every 3 weeks for five cycles). Responding patients continued pembrolizumab monotherapy for up to 17 cycles. Main eligibility requirements were a functional Eastern Cooperative Oncology Group status of 0-2, measurable or assessable disease, and no active autoimmune disease. Prior T-cell checkpoint antibody therapy was permitted.

RESULTS

Objective response was observed in 50% of MM (7/14) and and 33% of HNSCC (2/6) patients. Belapectin+pembrolizumab was associated with fewer immune-mediated adverse events than anticipated with pembrolizumab monotherapy. There were no dose-limiting toxicities for belapectin within the dose range investigated. Significantly increased effector memory T-cell activation and reduced monocytic myeloid-derived suppressor cells (M-MDSCs) were observed in responders compared with non-responders. Increased baseline expression of Gal-3+ tumor cells and PD-1+CD8+ T cells in the periphery correlated with response as did higher serum trough levels of pembrolizumab.

CONCLUSIONS

Belapectin+pembrolizumab therapy has activity in MM and HNSCC. Increased Gal-3 expression, expansion of effector memory T cells, and decreased M-MDSCs correlated with clinical response. Further investigation is planned.

Conversion of AML-blasts to leukemia-derived dendritic cells (DCleu) in 'DC-culture-media' shifts correlations of released chemokines with antileukemic T-cell reactions

Dendritic cells (DC) and T-cells are mediators of CTL-responses. Autologous (from patients with acute myeloid leukaemia (AML) or myelodysplasia (MDS)) or allogeneic (donor)-T-cells stimulated by DC_leu, gain an efficient lysis of naive blasts, although not in every case. CXCL8, -9, -10, CCL2, -5 and Interleukin (IL-12) were quantified by Cytometric Bead Array (CBA) in supernatants from 5 DC-generating methods and correlated with AML-/MDS-patients' serum-values, DC-/T-cell-interactions/antileukemic T-cell-reactions after mixed lymphocyte culture (MLC) and patients' clinical course. The blast-lytic activity of T-cells stimulated with DC or mononuclear cells (MNC) was quantified in a cytotoxicity assay. Despite great variations of chemokine-levels, correlations with post-stimulation (after stimulating T-cells with DC in MLC) improved antileukemic T-cell activity were seen: higher released chemokine-values correlated with improved T-cells' antileukemic activity (compared to stimulation with blast-containing MNC) - whereas with respect to the corresponding serum values higher CXCL8-, -9-, and -10- but lower CCL5- and -2-release correlated with improved antileukemic activity of DC-stimulated (vs. blast-stimulated) T-cells. In DC-culture supernatants higher chemokine-values correlated with post-stimulation improved antileukemic T-cell reactivity, whereas higher serum-values of CXCL8, -9, and -10 but lower serum-values of CCL5 and -2 correlated with post-stimulation improved antileukemic T-cell-reactivity. In a context of 'DC'-stimulation (vs serum) this might point to a change of (CCL5 and -2-associated) functionality from a more 'inflammatory' or 'tumor-promoting' to a more 'antitumor'-reactive functionality. This knowledge could contribute to develop immune-modifying strategies that promote antileukemic (adaptive) immune-responses.

Macrophage CCL22 expression promotes lymphangiogenesis in patients with tongue squamous cell carcinoma via IL-4/STAT6 in the tumor microenvironment

The C-C motif chemokine ligand 22 (CCL22) chemokine is produced by M2-like tumor-associated macrophages (TAMs) in the tumor microenvironment. Chemokine C-C motif receptor 4 (CCR4), the CCL22 receptor, on T helper2 (Th2) cells leads to a Th2 cytokine-dominant environment. In our previous study, lymph node metastasis was the main predictor of tongue squamous cell carcinoma (SCC) via CCL22. Therefore, the present study aimed to investigate the effects of CCL22 and a Th2 cytokine-predominant tumor microenvironment on vascular endothelial growth factor (VEGF)-C expression and lymphangiogenesis. The post-operative courses of 110 patients with early-stage tongue SCC with a histopathological diagnosis based on the 8th TNM classification were followed up (mean/median follow-up time, 47.1/42.0 months) from surgery until death or the last follow-up visit, and subsequent lymph node relapse was assessed. Lymphangiogenesis and the immunohistochemical expression of several markers (CCL22, CCR4 and VEGF-C) were evaluated. The Kaplan-Meier method was used to plot lymph node relapse-free survival and overall survival curves, which were compared using the log-rank test. In vitro, the association between CCL22 and VEGF-C by interleukin (IL)-4/signal transducer and activator of transcription 6 (STAT6) stimulation was examined. Lymphangiogenesis was significantly associated with lymph node relapse (P<0.001) and a CCL22⁺ macrophage ratio (P<0.001). CCL22⁺ TAMs were positive for VEGF-C and surrounded by CCR4⁺ cells. Additionally, VEGF-C expression was increased in IL-4/STAT6-stimulated macrophages. In addition, the STAT6 signaling pathway was activated in the SCC cells in the deeply invaded part of the tumor along with the aggregated macrophages. In conclusion, TAM CCL22 expression led to lymph node relapse via VEGF-C expression within the tumor microenvironment and the IL-4/STAT6 signaling pathway in early stage tongue SCC. Additionally, the worst pattern of invasion and depth of invasion were revealed to be useful parameters for lymph node relapse in patients with tongue SCC. The present study suggested that CCL22 contributed to the role of M2-like differentiated TAMs in prognosis and lymph node relapse via IL-4/STAT6 and VEGF. The IL-4/STAT6 signaling pathway may be a new molecular target for tongue SCC.

Overexpressed CXCR4 and CCR7 on the surface of NK92 cell have improved migration and anti-tumor activity in human colon tumor model

Successive infusion of natural killer cells is increasingly being explored as a treatment for cancer patients. The inadequate homing of natural killer cells into the tumor site resulted in the poor efficacy of natural killer cells on solid tumors. For the adoptive transfer of tumor-directed natural killer cell has been proved effective, it is hypothesized that there must be more association between the tumor-produced chemokines and the natural killer cells-expressed chemokine receptors. Increased CXCL12 and CCL21 could ameliorated colorectal cancer via generating an anti-tumor environment by preferentially attracting natural killer cells which expressed the chemokine receptor CXCR4 and CCR7. This study demonstrated that overexpressed CXCR4 and CCR7 on the surface of NK92 cell enhanced their migration to human colon cells. Moreover, the administration of such natural killer cells resulted in tumor shrinkage and a significantly increased survival of experimental mice when compared to ones undergoing the treatment of xenografts with natural killer cells expressing only the mock control. These suggested that chemokine receptor engineered natural killer cells could be a promising tool to improve adoptive tumor immunotherapy.

A Multipurpose First-in-Human Study With the Novel CXCR7 Antagonist ACT-1004-1239 Using CXCL12 Plasma Concentrations as Target Engagement Biomarker

The C-X-C chemokine receptor 7 (CXCR7) has evolved as a promising, druggable target mainly in the immunology and oncology fields modulating plasma concentrations of its ligands CXCL11 and CXCL12 through receptor-mediated internalization. This "scavenging" activity creates concentration gradients of these ligands between blood vessels and tissues that drive directional cell migration. This randomized, double-blind, placebo-controlled first-in-human study assessed the safety, tolerability, pharmacokinetics, and pharmacodynamics of ACT-1004-1239, a first-in-class drug candidate small-molecule CXCR7 antagonist. Food effect and absolute bioavailability assessments were also integrated in this multipurpose study. Healthy male subjects received single ascending oral doses of ACT-1004-1239 (n = 36) or placebo (n = 12). At each of six dose levels (1-200 mg), repeated blood sampling was done over 144 hours for pharmacokinetic/pharmacodynamic assessments using CXCL11 and CXCL12 as biomarkers of target engagement. ACT-1004-1239 was safe and well tolerated up to the highest tested dose of 200 mg. CXCL12 plasma concentrations dose-dependently increased and more than doubled compared with baseline, indicating target engagement, whereas CXCL11 concentrations remained unchanged. An indirect-response pharmacokinetic/pharmacodynamic model well described the relationship between ACT-1004-1239 and CXCL12 concentrations across the full dose range, supporting once-daily dosing for future clinical studies. At doses ≥ 10 mg, time to reach maximum plasma concentration ranged from 1.3 to 3.0 hours and terminal elimination half-life from 17.8 to 23.6 hours. The exposure increase across the dose range was essentially dose-proportional and no relevant food effect on pharmacokinetics was determined. The absolute bioavailability was 53.0% based on radioactivity data after oral vs. intravenous ¹⁴ C-radiolabeled microtracer administration of ACT-1004-1239. Overall, these comprehensive data support further clinical development of ACT-1004-1239.

IL1β Promotes Immune Suppression in the Tumor Microenvironment Independent of the Inflammasome and Gasdermin D

IL1β is a central mediator of inflammation. Secretion of IL1β typically requires proteolytic maturation by the inflammasome and formation of membrane pores by gasdermin D (GSDMD). Emerging evidence suggests an important role for IL1β in promoting cancer progression in patients, but the underlying mechanisms are ill-defined. Here, we have shown a key role for IL1β in driving tumor progression in two distinct mouse tumor models. Notably, activation of the inflammasome, caspase-8, as well as the pore-forming proteins GSDMD and mixed lineage kinase domain-like protein in the host were dispensable for the release of intratumoral bioactive IL1β. Inflammasome-independent IL1β release promoted systemic neutrophil expansion and fostered accumulation of T-cell-suppressive neutrophils in the tumor. Moreover, IL1β was essential for neutrophil infiltration triggered by antiangiogenic therapy, thereby contributing to treatment-induced immunosuppression. Deletion of IL1β allowed intratumoral accumulation of CD8⁺ effector T cells that subsequently activated tumor-associated macrophages. Depletion of either CD8⁺ T cells or macrophages abolished tumor growth inhibition in IL1β-deficient mice, demonstrating a crucial role for CD8⁺ T-cell-macrophage cross-talk in the antitumor immune response. Overall, these results support a tumor-promoting role for IL1β through establishing an immunosuppressive microenvironment and show that inflammasome activation is not essential for release of this cytokine in tumors.