Cannabinoid receptor 2 plays a pro-tumorigenic role in non-small cell lung cancer by limiting anti-tumor activity of CD8+ T and NK cells

Endocannabinoid Receptor 2 Function is Associated with Tumor-Associated Macrophage Accumulation and Increases in T Cell Number to Initiate a Potent Antitumor Response in a Syngeneic Murine Model of Glioblastoma

Introduction: Glioblastoma patients have a highly immunosuppressive tumor microenvironment and systemic immunosuppression that comprise a major barrier to immune checkpoint therapy. Based on the production of endocannabinoids by glioblastomas, we explored involvement of endocannabinoid receptor 2 (CB2R), encoded by the CNR2 gene, which is predominantly expressed by immune cells, in glioblastoma-related immunosuppression. Materials & Methods: Bioinformatics of human glioblastoma databases was used to correlate enzymes involved in the synthesis and degradation of endocannabinoids, as well as CB2Rs, with patient overall survival. Intrastriatal administration of luciferase-expressing, murine GL261 glioblastoma cells was used to establish in in vivo glioblastoma model for characterization of tumor growth and intratumoral immune cell infiltration, as well as provide immune cells for in vitro co-culture experiments. Involvement of CB2Rs was determined by treatment with CB2R agonist (GW405833) or CB2R antagonist (AM630). ELISA, FACS, and immunocytochemistry were used to determine perforin, granzyme B, and surface marker levels. Results: Bioinformatics of human glioblastoma databases showed high expression of CB2R and elevated endocannabinoid production correlated with poorer prognosis, and involved immune-associated pathways. AM630treatment of GL261 glioblastoma-bearing mice induced a potent antitumor response, with survival plateauing at 50% on Day 40, when all control mice (median survival 28 days) and mice treated with GW405833 (median survival 21 days) had died. Luciferase tumor imaging revealed accelerated tumor growth by GW405833 treatment, but stable or regressing tumors in AM630-treated mice. Notably, in spleens, AM630 treatment caused an 83% decrease in monocytes/macrophages, and 1.8- and 1.6-fold increases in CD8+ and CD4+ cells, respectively. Within tumors, there was a corresponding decrease in tumor-associated macrophages (TAMs) and increase in CD8+ T cells. In vitro, lymphocytes from AM630-treated mice showed greater cytotoxic function (increased percentage of perforin- and granzyme B-positive CD8+ T cells). Discussion: These results suggest that inhibition of CB2R enhances both immunosuppressive TAM infiltration and systemic T-cell suppression through CB2R activation, and that inhibition of CB2Rs can potently counter both the immunosuppressive tumor microenvironment, as well as systemic immunosuppression in glioblastoma.

The Role of Cannabinoids in Advancing Cancer Treatment: Insights from Evidence-Based Medicine

PURPOSE OF REVIEW

This document critically examines the role of cannabinoids in cancer care during an era marked by rapid advancements in oncology and changing perceptions on cannabis. It traces the historical context of cannabis in medicinal use, navigating its journey from widespread acceptance, subsequent criminalization, to its resurgence in modern therapeutic applications, particularly within the framework of Evidence-Based Medicine (EBM).

RECENT FINDINGS

Anchored in EBM principles, this study synthesizes current research from clinical trials, systematic reviews, and meta-analyses to evaluate the efficacy and safety of cannabinoids in oncology. The focus is on their palliative effects, considering the nuances of effectiveness, risk assessment, and challenges inherent in translating these findings into clinical guidelines. The study seeks to bridge the gap between scientific research and clinical practice, offering insights to inform future oncological therapies and symptom management strategies involving cannabinoids. The potential benefits and risks of cannabinoid use in cancer treatment are assessed to guide clinicians and researchers in developing comprehensive, evidence-based approaches to patient care.

Exploring the interplay between cannabinoids and thymic functions

Cannabinoids, derived from the Cannabis sativa plant, have garnered increasing attention for their potential therapeutic applications in various diseases. The pharmacologically active compounds in Cannabis, such as delta-9-tetrahydrocannabinol and cannabidiol, exhibit diverse immunomodulatory properties. Although studies have explored the effects of cannabinoids on immune function, their specific interactions with the thymus, a primary immune organ critical for T-cell development and maturation, remain an intriguing area of investigation. As the thymus plays a fundamental role in shaping the immune repertoire, understanding the interplay between cannabinoids and thymic function may shed light on potential benefits or concerns associated with Cannabis-based therapies. This article aims to provide an overview of the current scientific knowledge regarding the impact of medicinal Cannabis on the thymus and its implications for disease treatment and immune health.

GPCRs: emerging targets for novel T cell immune checkpoint therapy

Although immune checkpoint blockade (ICB) has become the mainstay of treatment for advanced solid organ malignancies, success in revitalizing the host anticancer immune response remains limited. G-protein coupled receptors (GPCRs) are a broad family of cell-surface proteins that have been regarded as main players in regulating the immune system, namely by mediating the activity of T lymphocytes. Among the most novel immunoregulatory GPCRs include GPR171, lysophosphatidic acid receptors (LPARs), GPR68, cannabinoid receptor 2 (CB2), and prostaglandin E receptors, many of which have shown promise in mediating antitumor response via activation of cytotoxic T cells, inhibiting immunosuppressive lymphocytes, and facilitating immune cell infiltration within the tumor microenvironment across multiple types of cancers. This paper reviews our current understanding of some of the most novel GPCRs-their expression patterns, evolving roles within the immune system and cancer, potential therapeutic applications, and perspective for future investigation.

A review of natural products targeting tumor immune microenvironments for the treatment of lung cancer

Lung cancer (LC) produces some of the most malignant tumors in the world, with high morbidity and mortality. Tumor immune microenvironment (TIME), a component of the tumor microenvironment (TME), are critical in tumor development, immune escape, and drug resistance. The TIME is composed of various immune cells, immune cytokines, etc, which are important biological characteristics and determinants of tumor progression and outcomes. In this paper, we reviewed the recently published literature and discussed the potential uses of natural products in regulating TIME. We observed that a total of 37 natural compounds have been reported to exert anti-cancer effects by targeting the TIME. In different classes of natural products, terpenoids are the most frequently mentioned compounds. TAMs are one of the most investigated immune cells about therapies with natural products in TIME, with 9 natural products acting through it. 17 natural products exhibit anti-cancer properties in LC by modulating PD-1 and PD-L1 protein activity. These natural products have been extensively evaluated in animal and cellular LC models, but their clinical trials in LC patients are lacking. Based on the current review, we have revealed that the mechanisms of LC can be treated with natural products through TIME intervention, resulting in a new perspective and potential therapeutic drugs.

Mononuclear cell composition and activation in blood and mucosal tissue of eosinophilic esophagitis

Introduction

Eosinophilic esophagitis (EoE) is a chronic, inflammatory, antigen-driven disease of the esophagus. Tissue EoE pathology has previously been extensively characterized by novel transcriptomics and proteomic platforms, however the majority of surface marker determination and screening has been performed in blood due to mucosal tissue size limitations. While eosinophils, CD4+ T cells, mast cells and natural killer (NK) T cells were previously investigated in the context of EoE, an accurate picture of the composition of peripheral blood mononuclear cells (PBMC) and their activation is missing.

Methods

In this study, we aimed to comprehensively analyze the composition of peripheral blood mononuclear cells and their activation using surface marker measurements with multicolor flow cytometry simultaneously in both blood and mucosal tissue of patients with active EoE, inactive EoE, patients with gastroesophageal reflux disease (GERD) and controls. Moreover, we set out to validate our data in co-cultures of PBMC with human primary esophageal epithelial cells and in a novel inducible mouse model of eosinophilic esophagitis, characterized by extensive IL-33 secretion in the esophagus.

Results

Our results indicate that specific PBMC populations are enriched, and that they alter their surface expression of activation markers in mucosal tissue of active EoE. In particular, we observed upregulation of the immunomodulatory molecule CD38 on CD4+ T cells and on myeloid cells in biopsies of active EoE. Moreover, we observed significant upregulation of PD-1 on CD4+ and myeloid cells, which was even more prominent after corticosteroid treatment. With co-culture experiments we could demonstrate that direct cell contact is needed for PD-1 upregulation on CD4+ T cells. Finally, we validated our findings of PD-1 and CD38 upregulation in an inducible mouse model of EoE.

Discussion

Herein we show significant alterations in the PBMC activation profile of patients with active EoE in comparison to inactive EoE, GERD and controls, which could have potential implications for treatment. To our knowledge, this study is the first of its kind expanding the multi-color flow cytometry approach in different patient groups using in vitro and in vivo translational models.

Evaluation of regulatory T-cells in cancer immunotherapy: therapeutic relevance of immune checkpoint inhibition

The evolution of the complex immune system is equipped to defend against perilous intruders and concurrently negatively regulate the deleterious effect of immune-mediated inflammation caused by self and nonself antigens. Regulatory T-cells (Tregs) are specialized cells that minimize immune-mediated inflammation, but in malignancies, this feature has been exploited toward cancer progression by keeping the antitumor immune response in check. The modulation of Treg cell infiltration and their induction in the TME (tumor microenvironment) alongside associated inhibitory molecules, both soluble or membranes tethered in the TME, have proven clinically beneficial in boosting the tumoricidal activity of the immune system. Moreover, Treg-associated immune checkpoints pose a greater obstruction in cancer immunotherapy. Inhibiting or blocking active immune checkpoint signaling in combination with other therapies has proven clinically beneficial. This review summarizes the ontogeny of Treg cells and their migration, stability, and function in the TME. We also elucidate the Treg-associated checkpoint moieties that impede effective antitumor activity and harness these molecules for effective and targeted immunotherapy against cancer nuisance.

Enhanced CT-based radiomics model to predict natural killer cell infiltration and clinical prognosis in non-small cell lung cancer

Background

Natural killer (NK) cells are crucial for tumor prognosis; however, their role in non-small-cell lung cancer (NSCLC) remains unclear. The current detection methods for NSCLC are inefficient and costly. Therefore, radiomics represent a promising alternative.

Methods

We analyzed the radiogenomics datasets to extract clinical, radiological, and transcriptome data. The effect of NK cells on the prognosis of NSCLC was assessed. Tumors were delineated using a 3D Slicer, and features were extracted using pyradiomics. A radiomics model was developed and validated using five-fold cross-validation. A nomogram model was constructed using the selected clinical variables and a radiomic score (RS). The CIBERSORTx database and gene set enrichment analysis were used to explore the correlations of NK cell infiltration and molecular mechanisms.

Results

Higher infiltration of NK cells was correlated with better overall survival (OS) (P = 0.002). The radiomic model showed an area under the curve of 0.731, with 0.726 post-validation. The RS differed significantly between high and low infiltration of NK cells (P < 0.01). The nomogram, using RS and clinical variables, effectively predicted 3-year OS. NK cell infiltration was correlated with the ICOS and BTLA genes (P < 0.001) and macrophage M0/M2 levels. The key pathways included TNF-α signaling via NF-κB and Wnt/β-catenin signaling.

Conclusions

Our radiomic model accurately predicted NK cell infiltration in NSCLC. Combined with clinical characteristics, it can predict the prognosis of patients with NSCLC. Bioinformatic analysis revealed the gene expression and pathways underlying NK cell infiltration in NSCLC.

Comparative Study of the Immune Microenvironment in Heterotopic Tumor Models

The tumor microenvironment (TME) is pivotal in cancer progression and the response to immunotherapy. A "hot" tumor typically contains immune cells that promote anti-tumor immunity, predicting positive prognosis. "Cold" tumors lack immune cells, suggesting a poor outlook across various cancers. Recent research has focused on converting "cold" tumors into "hot" tumors to enhance the success of immunotherapy. A prerequisite for the studies of the TME is an accurate knowledge of the cell populations of the TME. This study aimed to describe the immune TME of lung and colorectal cancer and melanoma, focusing on lymphoid and myeloid cell populations. We induced heterotopic immunocompetent tumors in C57BL/6 mice, using KP and LLC (Lewis lung carcinoma) cells for lung cancer, MC38 cells for colorectal cancer, and B16-F10 cells for melanoma. Immune cell infiltration was analyzed using multicolor flow cytometry in single-cell suspensions after tumor excision. KP cell tumors showed an abundance of neutrophils and eosinophils; however, they contained much less adaptive immune cells, while LLC cell tumors predominated in monocytes, neutrophils, and monocyte-derived dendritic cells. Monocytes and neutrophils, along with a significant T cell infiltration, were prevalent in MC38 tumors. Lastly, B16-F10 tumors were enriched in macrophages, while showing only moderate T cell presence. In conclusion, our data provide a detailed overview of the immune TME of various heterotopic tumors, highlighting the variabilities in the immune cell profiles of different tumor entities. Our data may be a helpful basis when investigating new immunotherapies, and thus, this report serves as a helpful tool for preclinical immunotherapy research design.

Altered Treg Infiltration after Discoidin Domain Receptor 1 (DDR1) Inhibition and Knockout Promotes Tumor Growth in Lung Adenocarcinoma

Lung cancer is the leading cause of cancer-related death worldwide. Discoidin domain receptor 1 (DDR1), a tyrosine kinase receptor, has been associated with poor prognosis in patients with non-small cell lung cancer (NSCLC). However, its role in tumorigenesis remains poorly understood. This work aimed to explore the impact of DDR1 expression on immune cell infiltration in lung adenocarcinoma. Pharmacological inhibition and knockout of DDR1 were used in an immunocompetent mouse model of KRAS/p53-driven lung adenocarcinoma (LUAD). Tumor cells were engrafted subcutaneously, after which tumors were harvested for investigation of immune cell composition via flow cytometry. The Cancer Genome Atlas (TCGA) cohort was used to perform gene expression analysis of 509 patients with LUAD. Pharmacological inhibition and knockout of DDR1 increased the tumor burden, with DDR1 knockout tumors showing a decrease in CD8+ cytotoxic T cells and an increase in CD4+ helper T cells and regulatory T cells. TCGA analysis revealed that low-DDR1-expressing tumors showed higher FoxP3 (regulatory T-cell marker) expression than high-DDR1-expressing tumors. Our study showed that under certain conditions, the inhibition of DDR1, a potential therapeutic target in cancer treatment, might have negative effects, such as inducing a pro-tumorigenic tumor microenvironment. As such, further investigations are necessary.

Cannabinoids and the endocannabinoid system in immunotherapy: helpful or harmful?

Numerous studies in various cancer models have demonstrated that ingredients of cannabis can influence tumor growth through the endocannabinoid system (ECS), a network of molecules (mediators, receptors, transporters, enzymes) that maintains homeostasis and protection in many tissues. The main constituents of the ECS are the classical cannabinoid (CB) receptors, such as CB1 and CB2, their endogenous ligands (endocannabinoids), and the endocannabinoids' synthesizing and degrading enzymes. The role of the ECS in cancer is still unclear and its effects often depend on the tumor entity and the expression levels of CB receptors. Many studies have highlighted the tumor cell-killing potential of CB1 agonists. However, cannabis is also known as an immunosuppressant and some data suggest that the use of cannabis during immunotherapy worsens treatment outcomes in cancer patients. CB receptors are widely present in immune cells, and together with monoacylglycerol lipase, the 2-arachidonoylglycerol degrading enzyme, they could be critically involved in the regulation of the immune cell profile of the tumor microenvironment (TME), and hence in tumor progression. So far, data on the impact of the ECS in the immune-TME are still vague. In this review, we discuss the current understanding of the ECS on immunoregulation during tumor growth, and how it might affect the outcome of cancer immunotherapy.

Construction of an anoikis-associated lncRNA-miRNA-mRNA network reveals the prognostic role of β-elemene in non-small cell lung cancer

β-Elemene is the main active ingredient in Curcumae Rhizoma that exerts antitumour effects. Anoikis affects tumour development through various biological pathways in non-small cell lung cancer (NSCLC), but the regulation between β-elemene and anoikis remains to be explored. First, we explored the molecular expression patterns of anoikis-associated genes (AAGs) using consensus clustering and characterized the impact of AAGs on patient prognosis, clinical characteristics, and genomic instability. In addition, we revealed that AAG regulatory genes have rich interactions with β-elemene targets, and established a lncRNA-miRNA-mRNA network to explain the effect of β-elemene on anoikis. Finally, to reveal the prognostic effect of their correlation, the prognostic scoring model and clinical nomogram of β-elemene and anoikis were successfully established by least absolute shrinkage and selection operator (LASSO) and random forest algorithms. This prognostic scoring model containing noncoding RNA (ncRNA) can indicate the immunotherapy and mutational landscape, providing a novel theoretical basis and direction for the study of the antitumour mechanism of β-elemene in NSCLC patients.

Eight Weeks of Daily Cannabidiol Supplementation Improves Sleep Quality and Immune Cell Cytotoxicity

BACKGROUND

The endocannabinoid system is active in nervous and immune cells and involves the expression of two cannabinoid receptor genes (CB1 and CB2), along with endogenous endocannabinoid ligands, 2-arachidonoyl glycerol (2-AG) and arachidonoyl ethanolamide (anandamide), and their synthetic enzymes. Cannabidiol (CBD) is a non-intoxicating exogenous cannabinoid agonist derived from plants that, at high doses, has received FDA approval as an anticonvulsant for epileptic seizures, and at low doses is marketed as a food-grade supplement for improved mental health, sleep quality, and immunological function. At present, the predominance of published CBD clinical research has focused on ameliorative or disease-specific intervention, with few trials investigating CBD effects in healthy populations.

METHODS

This clinical study aimed to investigate the effects of 8 weeks of 50 mg oral CBD on mental health, sleep quantity and quality, and immune cell function in healthy, college-aged individuals. Twenty-eight participants (average age 25.9 ± 6.1 y) were randomized to receive either daily oral capsules of 50 mg of CBD (CB, n = 14) or a calorie-matched placebo (CN, n = 14). Participants completed pre- and post-intervention assessments, including anthropometric measurements, mental health surveys, sleep analysis, and immunological function assessments.

RESULTS

After completing the 8-week intervention, there were no significant changes in body weight and BMI (CN: 1.09 ± 0.89%: CB: 1.41 ± 1.07%), or body fat percentage (CN: 9.01 ± 7.51%: CB: 8.57 ± 7.81%), respectively (values are % change pre to post, p > 0.05). There were also no significant differences between CB and CN groups with respect to mental health measures, sleep quantity, or circulating immunophenotype as a result of the intervention. However, the CB group experienced significant improvements in sleep quality measured objectively using a sleep questionnaire (p = 0.0023) and enhanced Natural Killer (NK) immune cell function assessed in situ (p = 0.0125).

CONCLUSIONS

Eight weeks of daily 50 mg CBD may improve sleep quality, and NK immunosurveillance in healthy, younger adults.

Tumor microenvironment-derived monoacylglycerol lipase provokes tumor-specific immune responses and lipid profiles

We recently described that monoacylglycerol lipase (MGL) is present in the tumor microenvironment (TME), increasing tumor growth. In this study we compare the implications of MGL deficiency in the TME in different tumor types. We show that subcutaneous injection of KP (KrasLSL-G12D/p53fl/fl, mouse lung adenocarcinoma) or B16-F10 cells (mouse melanoma) induced tumor growth in MGL wild type (WT) and knockout (KO) mice. MGL deficiency in the TME attenuated the growth of KP cell tumors whereas tumors from B16-F10 cells increased in size. Opposite immune cell profiles were detected between the two tumor types in MGL KO mice. In line with their anti-tumorigenic function, the number of CD8+ effector T cells and eosinophils increased in KP cell tumors of MGL KO vs. WT mice whereas their presence was reduced in B16-F10 cell tumors of MGL KO mice. Differences were seen in lipid profiles between the investigated tumor types. 2-arachidonoylglycerol (2-AG) content significantly increased in KP, but not B16-F10 cell tumors of MGL KO vs. WT mice while other endocannabinoid-related lipids remained unchanged. However, profiles of phospho- and lysophospholipids, sphingomyelins and fatty acids in KP cell tumors were clearly distinct to those measured in B16-F10 cell tumors. Our data indicate that TME-localized MGL impacts tumor growth, as well as levels of 2-AG and other lipids in a tumor specific manner.

GPR116 receptor regulates the antitumor function of NK cells via Gαq/HIF1α/NF-κB signaling pathway as a potential immune checkpoint

BACKGROUND

NK cell is one of innate immune cells and can protect the body from cancer-initiating cells. It has been reported that GPR116 receptor is involved in inflammation and tumors. However, the effect of GPR116 receptor on the NK cells remains largely unclear.

RESULTS

We discovered that GPR116^-/- mice could efficiently eliminate pancreatic cancer through enhancing the proportion and function of NK cells in tumor. Moreover, the expression of GPR116 receptor was decreased upon the activation of the NK cells. Besides, GPR116^-/- NK cells showed higher cytotoxicity and antitumor activity in vitro and in vivo by producing more GzmB and IFNγ than wild-type (WT) NK cells. Mechanistically, GPR116 receptor regulated the function of NK cells via Gαq/HIF1α/NF-κB signaling pathway. Furthermore, downregulation of GPR116 receptor promoted the antitumor activity of NKG2D-CAR-NK92 cells against pancreatic cancer both in vitro and in vivo.

CONCLUSIONS

Our data indicated that GPR116 receptor had a negatively effect on NK cell function and downregulation of GPR116 receptor in NKG2D-CAR-NK92 cells could enhance the antitumor activity, which provides a new idea to enhance the antitumor efficiency of CAR NK cell therapy.