Cytokines in cancer immunotherapy

The Impact of Estrogen in the Tumor Microenvironment

Tumor immune escape is now a hallmark of cancer development, and therapies targeting these pathways have emerged as standard of care. Specifically, immune checkpoint signal blockade offers durable responses and increased overall survival. However, the majority of cancer patients still do not respond to checkpoint blockade immune therapy leading to an unmet need in tumor immunology research. Sex-based differences have been noted in the use of cancer immunotherapy suggesting that sex hormones such as estrogen may play an important role in tumor immune regulation. Estrogen signaling already has a known role in autoimmunity, and the estrogen receptor can be expressed across multiple immune cell populations and effect their regulation. While it has been well established that tumor cells such as ovarian carcinoma, breast carcinoma, and even lung carcinoma can be regulated by estrogen, research into the role of estrogen in the regulation of tumor-associated immune cells is still emerging. In this chapter, we discuss the role of estrogen in the tumor immune microenvironment and the possible immunotherapeutic implications of targeting estrogen in cancer patients.

Effects of polyclonal activators on cell differentiation and cytokine production of cultured invasive breast carcinoma of no special type, their association with tumour histopathological parameters and lymph node metastasis

Currently, a number of promising strategies and approaches to cancer treatment include differentiation therapy. However, theoretical and methodological foundations of this field are not yet well developed. The objective of this study was to determine the effects of a mixture of polyclonal activators (PAs; phytohaemagglutinin, concanavalin A and lipopolysaccharide) on cytokine production by biopsy samples of invasive breast carcinoma of no special type (IBC-NST) having various differentiation abilities and metastatic potentials as well as on differentiation status of the IBC-NST biopsy samples. We used ELISAs to investigate spontaneous and PA-stimulated cytokine production in the IBC-NST biopsy samples; from these data, we calculated a cytokine production stimulation index (SIPA). The effect of PAs on tumour cell differentiation was determined via a differentiation stimulation index (DSI). DSI was found to vary within the range 1.0-5.0. After treatment with PAs, in the IBC-NST biopsy samples of group I (DSI <1.25), the production of IL-2, IL-6, IL-8, IL-17, IL-18, IL-1β, IL-1Ra, TNF-α and GM-CSF increased; in the biopsy samples of group II (DSI >1.25), the production of IL-6, IL-1β, IL-1Ra, TNF-α, G-CSF and GM-CSF significantly increased, while the production of VEGF-A decreased. Receiver operating characteristic (ROC) analysis of SIPA revealed that increased production of IL-18 in the IBC-NST biopsy samples after exposure to PAs may block the PA-driven, cytokine-mediated differentiation of moderately differentiated into highly differentiated tumour cells. The ROC analysis also uncovered an association between the responses of tumour cells to PAs and lymph node metastasis observed in the patients. The findings suggest that there is a need for research aimed at finding new drugs for differentiating cancer therapy and at searching for targeted inducers of cytokine production or specific suppressors of their induction.

Molecular biology and targeted therapy in metastatic renal cell carcinoma

The treatment of metastatic renal cell carcinoma is challenging as it has proven to be relatively resistant to conventional oncological treatments. An improved understanding of the molecular biology of renal cell carcinoma has led to the development of a number of targeted therapies in metastatic renal cell carcinoma. This includes vascular endothelial growth factor inhibitors, tyrosine kinase inhibitors, mammalian target of rapamycin inhibitors and most recently immune checkpoint inhibitors. This article will review the mechanisms of development and progression of renal cell carcinoma as well as the mechanisms of current approved treatments in metastatic disease.

Level of evidence: Not applicable for this multicentre audit.

Cell-Based IL-15:IL-15Rα Secreting Vaccine as an Effective Therapy for CT26 Colon Cancer in Mice

Interleukin (IL)-15 is an essential immune-modulator with high potential for use in cancer treatment. Natural IL-15 has a low biological potency because of its short half-life and difficulties in mass-production. IL-15Rα, a member of the IL-15 receptor complex, is famous for its high affinity to IL-15 and its ability to lengthen the half-life of IL-15. We have double-transfected IL-15 and its truncated receptor IL-15Rα into CT26 colon cancer cells to target them for intracellular assembly. The secreted IL-15:IL-15Rα complexes were confirmed in ELISA and Co-IP experiments. IL-15:IL15Rα secreting clones showed a higher anti-tumor effect than IL-15 secreting clones. Furthermore, we also evaluated the vaccine and therapeutic efficacy of the whole cancercell vaccine using mitomycin C (MMC)-treated IL-15:IL15Rα secreting CT26 clones. Three sets of experiments were evaluated; (1) therapeutics, (2) vaccination, and (3) longterm protection. Wild-type CT26-bearing mice treated with a single dose of MMC-inactivated secreted IL-15:IL-15Rα clones prolonged survival compared to the control group. Survival of MMC-inactivated IL-15:IL-15Rα clone-vaccinated mice (without any further adjuvant) exceeded up to 100%. This protection effect even lasted for at least three months after the immunization. Secreted IL-15:IL-15Rα clones challenging trigger anti-tumor response via CD4+ T, CD8+ T, and natural killer (NK) cell-dependent cytotoxicity. Our result suggested that cell-based vaccine secreting IL-15:IL-15Rα, may offer the new tools for immunotherapy to treat cancer.

Anti-proliferative and immunomodulatory activities of fractions from methanol root extract of Abrus precatorius L

Background

Abrus precatorius possesses various therapeutic properties including anticancer potentials. This study evaluated the anti-proliferative activities of fractions of methanol root extract of A. precatorius on breast and cervical cancer cells and their immunomodulatory effect. Phytochemical screening was done by FTIR and GCMS. In vitro anti-proliferative effect was evaluated on human breast cancer (AU565) and cervical cancer (HeLa) cells and on murine fibroblast (NIH 3 T3) cells. Antioxidant activity was performed via DPPH radical scavenging assay. The immunomodulatory potential of fractions was evaluated by inhibition of phagocytes oxidative burst (ROS), Nitric oxide (NO) and proinflammatory cytokine TNF-α.

Results

A. precatorius fractions showed different chemical groups and were somewhat selective in antiproliferative activity against studied cancer cells. Ethyl acetate fraction showed the most significant antiproliferative activity with IC50 values of 18.10 μg/mL and 11.89 μg/mL against AU565 and HeLa cells respectively. Hexane fraction significantly (p < 0.05) inhibited HeLa cells (IC50 18.24 ± 0.16 μg/mL), whereas aqueous fraction showed mild inhibition (IC50 46.46 ± 0.14 μg/mL) on AU565 cell proliferation. All fractions showed no cytotoxicity against NIH-3 T3 murine fibroblast normal cells. All fractions showed potent and significant (p < 0.001) DPPH radical scavenging activity as well as suppressed phagocytic oxidative burst. Hexane (< 1 μg/mL), ethyl acetate (< 1 μg/mL), and butanol (5.74 μg/mL) fractions potently inhibited the cytokine TNF- α, hexane (< 1 μg/mL) and ethyl acetate (< 1 μg/mL) fractions also potently inhibited NO.

Conclusions

The antiproliferative activities and suppressive effect on the phagocytic oxidative burst, NO and proinflammatory cytokine might be due to the synergistic actions of bioactive compounds especially flavonoids present in the assayed fractions and therefore, suggest chemotherapeutic use of A. precatorius in cancer treatment.

Interleukin-15 in cancer immunotherapy: IL-15 receptor complex versus soluble IL-15 in a cancer cell-delivered murine leukemia model

Cytokines of the common γ-chain receptor family such as IL-15 are vital with respect to activating immune cells, sustaining healthy immune functions, and augmenting the anti-tumor activity of effector cells, making them ideal candidates for cancer immunotherapy. IL-15, either in its soluble form (IL-15sol) or complexed with IL-15Rα (IL-15Rc), has been shown to exhibit potent anti-tumor activities in various experimental cancer studies. Here we describe the impact of intraperitoneal IL-15 in a cancer cell-delivered IL-15 immunotherapy approach using the 70Z/3-L leukemia mouse model. Whereas both forms of IL-15 led to significantly improved survival rates compared to the parent cell line, there were striking differences in the extent of the improved survival: mice receiving cancer cells secreting IL-15sol showed significantly longer survival and protective long-term immunity compared to those producing IL-15Rc. Interestingly, injection of leukemia cells secreting IL-15sol lead to heightened expansion of CD4⁺ and CD8⁺ T-cell populations in the peritoneum compared to IL-15Rc. Cell-secreted IL-15Rc resulted in an influx and/or expansion of NK1.1⁺ cells in the peritoneum which was much less pronounced in the IL-15sol model. Furthermore, IL-15Rc but not IL-15sol lead to T-cell exhaustion and disease progression. To our knowledge, this is the first study detailing a significantly different biological effect of cell-delivered IL-15sol versus IL-15Rc in a mouse cancer immunotherapy study.

Cytokine-mediated communication: a quantitative appraisal of immune complexity

Intercellular communication mediated by cytokines is the main mechanism by which cells of the immune system talk to each other. Many aspects of cytokine signalling in the immune system have been explored in great detail at the structural, biophysical, biochemical and cellular levels. However, a systematic understanding of the quantitative rules that govern cytokine-mediated cell-to-cell communication is still lacking. Here, we discuss recent efforts in the field of systems immunology to bring about a quantitative understanding of cytokine-mediated communication between leukocytes and to provide novel insights into the orchestration of immune responses and inflammation.

JAK-STAT Signaling: A Double-Edged Sword of Immune Regulation and Cancer Progression

Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling mediates almost all immune regulatory processes, including those that are involved in tumor cell recognition and tumor-driven immune escape. Antitumor immune responses are largely driven by STAT1 and STAT2 induction of type I and II interferons (IFNs) and the downstream programs IFNs potentiate. Conversely, STAT3 has been widely linked to cancer cell survival, immunosuppression, and sustained inflammation in the tumor microenvironment. The discovery of JAK-STAT cross-regulatory mechanisms, post-translational control, and non-canonical signal transduction has added a new level of complexity to JAK-STAT governance over tumor initiation and progression. Endeavors to better understand the vast effects of JAK-STAT signaling on antitumor immunity have unearthed a wide range of targets, including oncogenes, miRNAs, and other co-regulatory factors, which direct specific phenotypical outcomes subsequent to JAK-STAT stimulation. Yet, the rapidly expanding field of therapeutic developments aimed to resolve JAK-STAT aberrations commonly reported in a multitude of cancers has been marred by off-target effects. Here, we discuss JAK-STAT biology in the context of immunity and cancer, the consequences of pathway perturbations and current therapeutic interventions, to provide insight and consideration for future targeting innovations.

Overview of Current Immunotherapies Targeting Mutated KRAS Cancers

The occurrence of somatic substitution mutations of the KRAS proto-oncogene is highly prevalent in certain cancer types, which often leads to constant activation of proliferative pathways and subsequent neoplastic transformation. It is often seen as a gateway mutation in carcinogenesis and has been commonly deemed as a predictive biomarker for poor prognosis and relapse when conventional chemotherapeutics are employed. Additionally, its mutational status also renders EGFR targeted therapies ineffective owing to its downstream location. Efforts to discover new approaches targeting this menacing culprit have been ongoing for years without much success, and with incidences of KRAS positive cancer patients being on the rise, researchers are now turning towards immunotherapies as the way forward. In this scoping review, recent immunotherapeutic developments and advances in both preclinical and clinical studies targeting K-ras directly or indirectly via its downstream signal transduction machinery will be discussed. Additionally, some of the challenges and limitations of various K-ras targeting immunotherapeutic approaches such as vaccines, adoptive T cell therapies, and checkpoint inhibitors against KRAS positive cancers will be deliberated.

Modeling cell-cell communication for immune systems across space and time

Communicating is crucial for cells to coordinate their behaviors. Immunological processes, involving diverse cytokines and cell types, are ideal for developing frameworks for modeling coordinated behaviors of cells. Here, we review recent studies that combine modeling and experiments to reveal how immune systems use autocrine, paracrine, and juxtacrine signals to achieve behaviors such as controlling population densities and hair regenerations. We explain that models are useful because one can computationally vary numerous parameters, in experimentally infeasible ways, to evaluate alternate immunological responses. For each model, we focus on the length-scales and time-scales involved and explain why integrating multiple length-scales and time-scales in a model remain challenging. We suggest promising modeling strategies for meeting this challenge and their practical consequences.

The Proteomic Effects of Pulsed Focused Ultrasound on Tumor Microenvironments of Murine Melanoma and Breast Cancer Models

Non-ablative pulsed focused ultrasound (pFUS) targets non-thermal forces that activate local molecular and cellular immune responses. Optimal parameters to stimulate immunotherapeutic tumor microenvironments (TME) and responses in different tumor types remain uninvestigated. Flank B16 murine melanoma and 4T1 breast tumors received 1 MHz pFUS at 1-8 MPa peak negative pressures (PNP) and were analyzed 24 hr post-sonication. Necrosis or hemorrhage were unaltered in both tumors, but pFUS induced DNA strand breaks in tumor cells at PNP ≥6 MPa. pFUS at >4 MPa suppressed anti-inflammatory cytokines in B16 tumors. pFUS to 4T1 tumors decreased anti-inflammatory cytokines and increased pro-inflammatory cytokines and cell adhesion molecules. pFUS at 6 MPa increased calreticulin and alterations in check-point proteins along with tumoral and splenic immune cell changes that could be consistent with a shift towards an anti-TME. pFUS-induced TME alterations shows promise in generating anti-tumor immune responses, but non-uniform responses between tumor types require additional investigation to assess pFUS as a suitable anti-tumor therapy.

Delivery strategies of cancer immunotherapy: recent advances and future perspectives

Immunotherapy has become an emerging strategy for the treatment of cancer. Immunotherapeutic drugs have been increasing for clinical treatment. Despite significant advances in immunotherapy, the clinical application of immunotherapy for cancer patients has some challenges associated with safety and efficacy, including autoimmune reactions, cytokine release syndrome, and vascular leak syndrome. Novel strategies, particularly improved delivery strategies, including nanoparticles, scaffolds, and hydrogels, are able to effectively target tumors and/or immune cells of interest, increase the accumulation of immunotherapies within the lesion, and reduce off-target effects. Here, we briefly describe five major types of cancer immunotherapy, including their clinical status, strengths, and weaknesses. Then, we introduce novel delivery strategies, such as nanoparticle-based delivery of immunotherapy, implantable scaffolds, injectable biomaterials for immunotherapy, and matrix-binding molecular conjugates, which can improve the efficacy and safety of immunotherapies. Also, the limitations of novel delivery strategies and challenges of clinical translation are discussed.

[An integral view of cancer (III). Evaluation of new biomarkers and treatment strategies]

We propose a comprehensive approach to oncological disease, based on a systemic consideration of biology, health and disease. Our two previous review articles focused on tumour microenvironment and the discovery of new biomarkers; here we discuss the practical application of these principles to pathology, through the identification, evaluation and quantitative analysis of new prognostic and predictive factors (Immunoscore, TIME). We also consider the clinical use of promising, better tolerated treatments, such as immunotherapy. The integrative pathologist now has access to the latest improved oncology stratification tools designed to identify effective treatment strategies, based on the natural evolution of clinical and scientific knowledge that transcend the gene-centric theory of cancer.

Recent advances and challenges of repurposing nanoparticle-based drug delivery systems to enhance cancer immunotherapy

Cancer immunotherapy is an attractive treatment option under clinical settings. However, the major challenges of immunotherapy include limited patient response, limited tumor specificity, immune-related adverse events, and immunosuppressive tumor microenvironment. Therefore, nanoparticle (NP)-based drug delivery has been used to not only increase the efficacy of immunotherapeutic agents, but it also significantly reduces the toxicity. In particular, NP-based drug delivery systems alter the pharmacokinetic (PK) profile of encapsulated or conjugated immunotherapeutic agents to targeted cancer cells or immune cells and facilitate the delivery of multiple therapeutic combinations to targeted cells using single NPs. Recently, advanced NP-based drug delivery systems were effectively utilized in cancer immunotherapy to reduce the toxic side effects and immune-related adverse events. Repurposing these NPs as delivery systems of immunotherapeutic agents may overcome the limitations of current cancer immunotherapy. In this review, we focus on recent advances in NP-based immunotherapeutic delivery systems, such as immunogenic cell death (ICD)-inducing drugs, cytokines and adjuvants for promising cancer immunotherapy. Finally, we discuss the challenges facing current NP-based drug delivery systems that need to be addressed for successful clinical application.

Nanoparticle Delivery of Immunostimulatory Agents for Cancer Immunotherapy

Immunostimulatory agents, including adjuvants, cytokines, and monoclonal antibodies, hold great potential for the treatment of cancer. However, their direct administration often results in suboptimal pharmacokinetics, vulnerability to biodegradation, and compromised targeting. More recently, encapsulation into biocompatible nanoparticulate carriers has become an emerging strategy for improving the delivery of these immunotherapeutic agents. Such approaches can address many of the challenges facing current treatment modalities by endowing additional protection and significantly elevating the bioavailability of the encapsulated payloads. To further improve the delivery efficiency and subsequent immune responses associated with current nanoscale approaches, biomimetic modifications and materials have been employed to create delivery platforms with enhanced functionalities. By leveraging nature-inspired design principles, these biomimetic nanodelivery vehicles have the potential to alter the current clinical landscape of cancer immunotherapy.

Inhibitory effects of flavonoids isolated from Sophora flavescens on indoleamine 2,3-dioxygenase 1 activity

Indoleamine 2,3-dioxygenase 1 (IDO1), a tryptophan catabolising enzyme, is known as a tumour cell survival factor that causes immune escape in several types of cancer. Flavonoids of Sophora flavescens have a variety of biological benefits for humans; however, cancer immunotherapy effect has not been fully investigated. The flavonoids (1-6) isolated from S. flavescens showed IDO1 inhibitory activities (IC₅₀ 4.3-31.4 µM). The representative flavonoids (4-6) of S. flavescens were determined to be non-competitive inhibitors of IDO1 by kinetic analyses. Their binding affinity to IDO1 was confirmed using thermal stability and surface plasmon resonance (SPR) assays. The molecular docking analysis and mutagenesis assay revealed the structural details of the interactions between the flavonoids (1-6) and IDO1. These results suggest that the flavonoids (1-6) of S. flavescens, especially kushenol E (6), as IDO1 inhibitors might be useful in the development of immunotherapeutic agents against cancers.

Genomics-Guided Immunotherapy for Precision Medicine in Cancer

Next-generation sequencing (NGS) data have been central to the development of targeted therapy and immunotherapy for precision oncology. In targeted therapy, drugs directly attack cancer, by altering the expression of critical cancer genes identified with cancer genome profiling. Immunotherapy drugs indirectly attack cancer, by inducing the immune system to attack and treat cancer. Harnessing genomic data for deployment and development of immunotherapy comprises the field of immunogenomics. The discovery of a link between cancer cells escaping immune destruction and cancer progression, led to extensive research into this mechanism and drug development. In the past few years, FDA has granted accelerated approval to several immunotherapy cancer treatment drugs, pembrolizumab, nivolumab, and atezolizumab, belonging to the class of checkpoint inhibitors. Utilization of pretreatment genomic cancer screening to identify patients most likely to respond to immunotherapy and to customize immunotherapy for a given patient, promises to improve cancer treatment outcomes. Recent advances in molecular profiling, high-throughput sequencing, and computational efficiency has made immunogenomics the major tenet of precision medicine in cancer treatment. This review provides a brief overview on the state of art of immunogenomics in precision cancer medicine.

Drug Delivery for Cancer Immunotherapy and Vaccines

Cancer cells are able to avoid immune surveillance and exploit the immune system to grow and metastasize. With the development of nano- and micro-particles, there has been a growing number of immunotherapy delivery systems developed to elicit innate and adaptive immune responses to eradicate cancer cells. This can be accomplished by training resident immune cells to recognize and eliminate cells with tumor-associated antigens or by providing external stimuli to enhance tumor cell apoptosis in the immunosuppressive tumor microenvironment (TME). In this review we will focus on nano- and micro-particle (NP and MP) based immunotherapies and vaccines used to elicit a potent and sustained antitumor immune response.

Canine multicentric lymphoma exhibits systemic and intratumoral cytokine dysregulation

Non-Hodgkin Lymphoma (NHL) is among the most common neoplasias in dogs and humans. Owing to remarkable similarities with its human counterpart, the canine lymphoma (cNHL) model has been proposed as a powerful framework for rapid and clinically relevant translation of novel immunotherapies. However, the establishment of cNHL as a predictive preclinical model has been hampered by the limited characterization of the canine immune system. Cytokines are key players of the interaction between tumor and its microenvironment. In human NHL, multiple cytokines have been linked to the development of lymphoma and are relevant biomarkers for treatment response and prognosis. In contrast, few studies have investigated cytokines in cNHL. Within this context, this study aimed to investigate cytokine regulation in cNHL. A multicentric cNHL biobank was successfully constructed. Cytokine mRNA profiles in tumor tissue and circulating PBMC were analyzed by qRT-PCR and compared to a healthy control group. Specific primers were used to evaluate Th1, Th2 and Th17 responses. Systemic cytokine concentrations were measured using a commercial canine multiplex assay which included IL-2, IL6, IL-10 and TNF-α, and compared to a healthy control group. Our results demonstrated a dysregulation of cytokine mRNA expression, representative of the tumor microenvironment and systemic response in cNHL. Intratumoral cytokine response revealed a significant downregulation of humoral and Th1 responses. The systemic response demonstrated a distinct mRNA pattern, however immunosuppression also prevailed. Cytokine serum quantification showed a significant increase of IL-10 concentration in cNHL. Significant differences in hematological parameters were described and a correlation between IL-6 protein serum levels and neutrophil count was shown. Finally, data analysis demonstrated that baseline pretreatment IFN-γ tissue mRNA levels were correlated to survival outcome, predicting a favorable response to chemotherapy. Altogether, these results revealed that cNHL presents a local and systemic dysregulation in cytokine response. By confirming and extending previous research, our work contributed for the evaluation of potential cytokine candidates for diagnostic, prognostic purposes and therapeutic intervention, therefore adding value to comparative oncology.

Decursin inhibits tumor growth, migration, and invasion in gastric cancer by down-regulating CXCR7 expression

CXC chemokine receptor 7 (CXCR7) is highly expressed in various type of cancers and promotes cancer progression and metastasis. However, the biological role and regulation of CXCR7 in gastric cancer remains unclear, and little is known about compounds that modulate CXCR7. Here, we investigated the role of CXCR7 in gastric tumorigenesis, and the effects of decursin, which is derived from Angelica gigas Nakai, on CXCR7. Our results showed that CXCR7 significantly promoted growth of gastric cancer cells and increased migration and invasion, which was mediated by the STAT3/c-Myc pathway. We also confirmed that decursin had an antitumor effect through down-regulating the expression of CXCR7 in gastric cancer. Furthermore, apoptotic cell death was induced through the reduction of anti-apoptotic factors such as Bcl-2 in vitro and in vivo. Our findings show that CXCR7 in gastric cancer promotes cancer progression through the STAT3/c-Myc pathway and that decursin is a natural compound that may target CXCR7 in gastric cancer treatment.

SMAR1 favors immunosurveillance of cancer cells by modulating calnexin and MHC I expression

Down-regulation or loss of MHC class I expression is a major mechanism used by cancer cells to evade immunosurveillance and increase their oncogenic potential. MHC I mediated antigen presentation is a complex regulatory process, controlled by antigen processing machinery (APM) dictating immune response. Transcriptional regulation of the APM that can modulate gene expression profile and their correlation to MHC I mediated antigen presentation in cancer cells remain enigmatic. Here, we reveal that Scaffold/Matrix-Associated Region 1- binding protein (SMAR1), positively regulates MHC I surface expression by down-regulating calnexin, an important component of antigen processing machinery (APM) in cancer cells. SMAR1, a bonafide MAR binding protein acts as a transcriptional repressor of several oncogenes. It is down-regulated in higher grades of cancers either through proteasomal degradation or through loss of heterozygosity (LOH) at the Chr.16q24.3 locus where the human homolog of SMAR1 (BANP) has been mapped. It binds to a short MAR region of the calnexin promoter forming a repressor complex in association with GATA2 and HDAC1. A reverse correlation between SMAR1 and calnexin was thus observed in SMAR1-LOH cells and also in tissues from breast cancer patients. To further extrapolate our findings, influenza A (H1N1) virus infection assay was performed. Upon viral infection, the levels of SMAR1 significantly increased resulting in reduced calnexin expression and increased MHC I presentation. Taken together, our observations establish that increased expression of SMAR1 in cancers can positively regulate MHC I surface expression thereby leading to higher chances of tumor regression and elimination of cancer cells.

Naturally Killing the Silent Killer: NK Cell-Based Immunotherapy for Ovarian Cancer

Ovarian cancer (OC) is diagnosed in ~22,000 women in the US each year and kills 14,000 of them. Often, patients are not diagnosed until the later stages of disease, when treatment options are limited, highlighting the urgent need for new and improved therapies for precise cancer control. An individual's immune function and interaction with tumor cells can be prognostic of the response to cancer treatment. Current emerging therapies for OC include immunotherapies, which use antibodies or drive T cell-mediated cancer recognition and elimination. In OC, these have been limited by adverse side effects and tumor characteristics including inter- and intra-tumoral heterogeneity, lack of targetable antigens, loss of tumor human leukocyte antigen expression, high levels of immunosuppressive factors, and insufficient immune cell trafficking. Natural killer (NK) cells may be ideal as primary or collateral effectors to these nascent immunotherapies. NK cells exhibit multiple functions that combat immune escape and tumor relapse: they kill targets and elicit inflammation through antigen-independent pathways and detect loss of HLA as a signal for activation. NK cells are efficient mediators of tumor immune surveillance and control, suppressed by the tumor microenvironment and rescued by immune checkpoint blockade. NK cells are regulated by a variety of activating and inhibitory receptors and already known to be central effectors across an array of existing therapies. In this article, we highlight interactions between NK cells and OC and their potential to change the immunosuppressive tumor microenvironment and participate in durable immune control of OC.

Role of cell surface proteoglycans in cancer immunotherapy

Over the past few decades, understanding how tumor cells evade the immune system and their communication with their tumor microenvironment, has been the subject of intense investigation, with the aim of developing new cancer immunotherapies. The current therapies against cancer such as monoclonal antibodies against checkpoint inhibitors, adoptive T-cell transfer, cytokines, vaccines, and oncolytic viruses have managed to improve the clinical outcome of the patients. However, in some tumor entities, the response is limited and could benefit from the identification of novel therapeutic targets. It is known that tumor-extracellular matrix interplay and matrix remodeling are necessary for anti-tumor and pro-tumoral immune responses. Proteoglycans are dominant components of the extracellular matrix and are a highly heterogeneous group of proteins characterized by the covalent attachment of a specific linear carbohydrate chain of the glycosaminoglycan type. At cell surfaces, these molecules modulate the expression and activity of cytokines, chemokines, growth factors, adhesion molecules, and function as signaling co-receptors. By these mechanisms, proteoglycans influence the behavior of cancer cells and their microenvironment during the progression of solid tumors and hematopoietic malignancies. In this review, we discuss why cell surface proteoglycans are attractive pharmacological targets in cancer, and we present current and recent developments in cancer immunology and immunotherapy utilizing proteoglycan-targeted strategies.

Colorectal carcinoma in the course of inflammatory bowel diseases

Background

Colorectal cancer (CRC) and inflammatory bowel disease (IBD) are the most prevalent diseases of the digestive system, and their association is unequivocal. A long-standing inflammatory process is one of the causes of sporadic as well as inherited cancers as it impacts on malignant transformation in a wide variety of neoplastic diseases, including colorectal cancer.

Methods

An extensive publication search was performed in Medline and PubMed database. The keywords: colorectal carcinoma, inflammation, Crohn disease, ulcerative colitis and inflammatory bowel disease were used.

Results

The nucleotide-binding oligomerization domain-containing protein 2 (NOD2) and toll like receptor (TLR) signaling pathways are clearly involved in the inflammatory process and are therefore implicated in the transformation of normal colonic mucosa to premalignant and malignant disease. Focal sites of inflammation could significantly increase the risk of initiation and development of cancer. Altered inflammatory activity is likely to be a result of either a disturbance of intestinal bacterial flora or an inadequate cellular response to it. Additionally, increasing the level of inflammation-related factors may also interfere with the control of cellular proliferation.

Conclusions

This review shows an overview of the genetic and environmental factors that appear to influence both the occurrence of IBD and CRC with particular reference to NOD2 and TLRs as well as pro- and anti-inflammatory cytokines associated with tumor initiation and progression (encompassing both tumor invasion and metastases), as they constitute potential targets for therapeutic intervention.

Key candidate genes of STAT1 and CXCL10 in melanoma identified by integrated bioinformatical analysis

The underlying mechanisms and gene signatures of melanoma are unknown. In this study, three expression profile data sets (GSE65568, GSE100050, GSE114445) were integrated to identify candidate genes explaining the pathways and functions of melanoma. Expression data sets including 24 melanoma tumours and 13 normal skin samples were merged and analysed in detail. The three GSE profiles shared 431 differentially expressed genes (DEGs), including 227 upregulated genes, 200 downregulated genes and 4 differentially regulated genes. Moreover, the functions and signalling pathways of the shared DEGs with significant p-values were identified. The two most significant modules were filtered from the DEGs protein-protein interaction (PPI) network, which consisted of 284 nodes. We also plotted the prognostic value of hub genes from an online database. In summary, using integrated bioinformatic analysis, we have identified candidate DEGs and pathways in melanoma that could improve our understanding of the causes and underlying molecular events of melanoma, and these candidate genes and pathways could be therapeutic targets for melanoma.

Novel TCR-based biologics: mobilising T cells to warm 'cold' tumours

Immunotherapeutic strategies have revolutionised cancer therapy in recent years, bringing meaningful improvements in outcomes for patients with previously intractable conditions. These successes have, however, been largely limited to certain types of liquid tumours and a small subset of solid tumours that are known to be particularly immunogenic. Broadening these advances across the majority of tumour indications, which are characterised by an immune-excluded, immune-deserted or immune-suppressed ('cold') phenotype, will require alternative approaches that are able to specifically address this unique biological environment. Several newer therapeutic modalities, including adoptive cell therapy and T cell redirecting bispecific molecules, are considered to hold particular promise and are being investigated in early phase clinical trials across various solid tumour indications. ImmTAC molecules are a novel class of T cell redirecting bispecific biologics that exploit TCR-based targeting of tumour cells; providing potent and highly specific access to the vast landscape of intracellular targets. The first of these reagents to reach the clinic, tebentafusp (IMCgp100), has generated demonstrable clinical efficacy in an immunologically cold solid tumour with a high unmet need. Here, we highlight the key elements of the ImmTAC platform that make it ideally positioned to overcome the cold tumour microenvironment in an off-the-shelf format.

Modulating inflammation for cancer therapy

A link between chronic inflammation and development of tumors is well established. Moreover, it has become evident that tumorigenesis is not a cell autonomous disease, and an inflammatory microenvironment is a prerequisite of basically all tumors, including those that emerge in the absence of overt inflammation. This knowledge has led to the development of anti-inflammatory concepts to treat and prevent cancer. In contrast, immunotherapies, in particular checkpoint inhibitors, representing the most significant progress in the therapy of several malignancies depend on the presence of a pro-inflammatory "hot" environment. Here, we discuss pro- and anti-inflammatory concepts for the treatment of cancer.

The antineoplastic agent anacardic 6-pentadecyl salicylic acid produces immunomodulation in vivo via the activation of MAPKs

Anacardic 6-pentadecyl salicylic acid (6SA) is the active component of Amphipterygium adstringens, a plant used in traditional medicine for the treatment of malaria and vascular diseases and as an anti-bacterial and immune-modulatory agent. However, the effect of 6SA on the immune system remains unclear. In this study, we examined the immune-stimulatory activity of 6SA in 6-8-week-old female BALB/c mice. We found that treatment with 2 mg/kg of 6SA increased the proportions of macrophages after 7 and 14 days of treatment and of natural killer (NK) cells after 14 days of treatment in circulating blood. In lymph nodes, treatment with 6SA for 14 days increased the number of macrophages. In addition, 6SA increases in the systemic levels of pro-inflammatory cytokines such as tumour necrosis factor (TNF)-α, interleukin (IL)-2, IL-12, IL-6 and IL-1β and of nitric oxide (NO). We observed an increase in the secretion of Granulocyte/Macrophage Colony Stimulation Factor (GM-CSF) that could explain the increase in the proportion of macrophages. Moreover, 6SA induced the classical activation of macrophages by increasing their expression of MHC-II and their production of TNF-α. These M1-polarised macrophages presented enhanced phagocytosis and NO secretion. This activation was due to induction of the phosphorylation of MAPKs such as ERK, JNK and p38 because specific inhibitors of the phosphorylation of these MAPKs reduced the 6SA-induced phagocytosis and NO and particularly, the secretion of GM-CSF in macrophages by inhibition of ERK. Despite these effects on macrophages, 6SA does not have any direct effect on the proportion of lymphocytes.

mRNA Delivery for Therapeutic Anti-HER2 Antibody Expression In Vivo

Antibody-based drugs are a leading class of biologics used to treat a variety of diseases, including cancer. However, wide antibody implementation is hindered by manufacturing challenges and high production cost. Use of in-vitro-transcribed mRNA (IVT-mRNA) for endogenous protein expression has the potential to circumvent many of the shortcomings of antibody production and therapeutic application. Here, we describe the development of an IVT-mRNA system for in vivo delivery of a humanized anti-HER2 (also known as ERBB2) antibody, trastuzumab, and demonstrate its anticancer activity. We engineered the IVT-mRNA sequence to maximize expression, then formulated the IVT-mRNA into lipid-based nanoparticles (LNPs) to protect the mRNA from degradation and enable efficient in vivo delivery. Systemic delivery of the optimized IVT-mRNA loaded into LNPs resulted in antibody serum concentrations of 45 ± 8.6 μg/mL for 14 days after LNP injection. Further studies demonstrated an improved pharmacokinetic profile of the produced protein compared to injection of trastuzumab protein. Finally, treatment of tumor-bearing mice with trastuzumab IVT-mRNA LNPs selectively reduced the volume of HER2-positive tumors and improved animal survival. Taken together, the results of our study demonstrate that using IVT-mRNA LNPs to express full-size therapeutic antibodies in the liver can provide an effective strategy for cancer treatment and offers an alternative to protein administration.

The B-side of Cancer Immunity: The Underrated Tune

Tumor-infiltrating lymphocytes are known to be critical in controlling tumor progression. While the role of T lymphocytes has been extensively studied, the function of B cells in this context is still ill-defined. In this review, we propose to explore the role of B cells in tumor immunity. First of all we define their dual role in promoting and inhibiting cancer progression depending on their phenotype. To continue, we describe the influence of different tumor microenvironment factors such as hypoxia on B cells functions and differentiation. Finally, the role of B cells in response to therapy and as potential target is examined. In accordance with the importance of B cells in immuno-oncology, we conclude that more studies are required to throw light on the precise role of B cells in the tumor microenvironment in order to have a better understanding of their functions, and to design new strategies that efficiently target these cells by immunotherapy.

Interleukin-17F Has Anti-Tumor Effects in Oral Tongue Cancer

We recently showed that extracellular interleukin-17F (IL-17F) correlates with better disease-specific survival in oral tongue squamous cell carcinoma (OTSCC) patients. However, the underlying mechanisms of such effect remain obscure. Here, we used qRT-PCR to assess the expression of IL-17F and its receptors (IL-17RA and IL-17RC) in two OTSCC cell lines (HSC-3 and SCC-25) and in normal human oral keratinocytes (HOKs). IL-17F effects on cancer cell proliferation, migration, and invasion were studied using a live-imaging IncuCyte system, and a Caspase-3/7 reagent was used for testing apoptosis. 3D tumor spheroids were utilized to assess the impact of IL-17F on invasion with or without cancer-associated fibroblasts (CAFs). Tube-formation assays were used to examine the effects of IL-17F on angiogenesis using human umbilical vein endothelial cells (HUVEC). OTSCC cells express low levels of IL-17F, IL-17RA, and IL-17RC mRNA compared with HOKs. IL-17F inhibited cell proliferation and random migration of highly invasive HSC-3 cells. CAFs promoted OTSCC invasion in tumor spheroids, whereas IL-17F eliminated such effect. IL-17F suppressed HUVEC tube formation in a dose-dependent manner. Collectively, we suggest that IL-17F counteracts the pro-tumorigenic activity in OTSCC. Due to its downregulation in tumor cells and inhibitory activity in in vitro cancer models, targeting IL-17F or its regulatory pathways could lead to promising immunotherapeutic strategies against OTSCC.

Immunoepigenetics Combination Therapies: An Overview of the Role of HDACs in Cancer Immunotherapy

Long-standing efforts to identify the multifaceted roles of histone deacetylase inhibitors (HDACis) have positioned these agents as promising drug candidates in combatting cancer, autoimmune, neurodegenerative, and infectious diseases. The same has also encouraged the evaluation of multiple HDACi candidates in preclinical studies in cancer and other diseases as well as the FDA-approval towards clinical use for specific agents. In this review, we have discussed how the efficacy of immunotherapy can be leveraged by combining it with HDACis. We have also included a brief overview of the classification of HDACis as well as their various roles in physiological and pathophysiological scenarios to target key cellular processes promoting the initiation, establishment, and progression of cancer. Given the critical role of the tumor microenvironment (TME) towards the outcome of anticancer therapies, we have also discussed the effect of HDACis on different components of the TME. We then have gradually progressed into examples of specific pan-HDACis, class I HDACi, and selective HDACis that either have been incorporated into clinical trials or show promising preclinical effects for future consideration. Finally, we have included examples of ongoing trials for each of the above categories of HDACis as standalone agents or in combination with immunotherapeutic approaches.

Combination of Immunotherapy With Targeted Therapy: Theory and Practice in Metastatic Melanoma

Metastatic melanoma is the most aggressive and obstinate skin cancer with poor prognosis. Variant novel applicable regimens have emerged during the past decades intensively, while the most profound approaches are oncogene-targeted therapy and T-lymphocyte mediated immunotherapy. Although targeted therapies generated remarkable and rapid clinical responses in the majority of patients, acquired resistance was developed promptly within months leading to tumor relapse. By contrast, immunotherapies elicited long-term tumor regression. However, the overall response rate was limited. In view of the above, either targeted therapy or immunotherapy cannot elicit durable clinical responses in large range of patients. Interestingly, the advantages and limitations of these regimens happened to be complementary. An increasing number of preclinical studies and clinical trials proved a synergistic antitumor effect with the combination of targeted therapy and immunotherapy, implying a promising prospect for the treatment of metastatic melanoma. In order to achieve a better therapeutic effectiveness and reduce toxicity in patients, great efforts need to be made to illuminate multifaceted interplay between targeted therapy and immunotherapy.

From immune checkpoints to vaccines: The past, present and future of cancer immunotherapy

Cancer is a worldwide medical problem with significant repercussions on individual patients and societies as a whole. In order to alter the outcomes of this deadly disease the treatment of cancer over the centuries has undergone a unique evolution. However, utilizing the best treatment modalities and achieving cures or long-term durable responses have been inconsistent and limited, that is until recently. Contemporary research has highlighted a fundamental gap in our understanding of how we approach treating cancer, by revealing the intricate relationship between the immune system and tumors. In this atmosphere, the growth of immunotherapy has not only forever changed our understanding of cancer biology, but the manner by which we treat patients. It's paradigm shifting success has led to the approval of over 10 different immunotherapeutic agents, including checkpoint inhibitors, vaccine-based therapies, oncolytic viruses and T cell directed therapies for nearly 20 different indications across countless tumor types. Despite the breakthroughs that have occurred in the field of immunotherapy, it has not been the panacea for all cancers. With a deeper understanding of the immune system we have been able to peer into tumor immune escape and therapy resistance. Simultaneously this understanding has paved the way for the investigation and development of novel immune system altering agents and combinatorial therapies. In this chapter we review the immune system and its intricate relationship with cancer, the evolution of immunotherapy, its current landscape, and future directions in the context of resistance mechanisms and the challenges faced by immunotherapy against cancer.

CD19 chimeric antigen receptor-redirected T cells combined with epidermal growth factor receptor pathway substrate 8 peptide-derived dendritic cell vaccine in leukemia

BACKGROUND

Chimeric antigen receptor (CAR)-T cell therapy opens a new era for cancer treatment. However, in prolonged follow-up, relapse has emerged as one of the major obstacles. Dendritic cell (DC) vaccination is a promising treatment to eradicate tumor cells and prevent relapse. The epidermal growth factor receptor (EGFR) pathway substrate 8 (Eps8) gene is involved in regulating cancer progression and is considered an attractive target for specific cancer immunotherapy. The purpose of this study was to explore a combinatorial therapy using CAR-T cells and a DC vaccine such as Eps8-DCs to increase leukemia treatment efficacy.

METHODS

We pulsed DCs with Eps8-derived peptides to generate Eps8-DCs, engineered T cells to express a second-generation CAR specific for CD19, and analyzed the effects of the Eps8-DCs on the in vitro expansion, phenotype and effector functions of the CD19 CAR-T cells.

RESULTS

The Eps8-DCs significantly reduced the activation-induced cell death and enhanced the proliferative potential of CAR-T cells during in vitro expansion. In addition, the expanded T cells co-cultured with the Eps8-DCs exhibited an increased percentage of central memory T cells (Tcms) and a decreased percentage of effector memory T cells (Tems). The Eps8-DCs enhanced CD19 CAR-T cell immune functions, including cytokine production, CD107a degranulation activity and cytotoxicity.

DISCUSSION

This study demonstrates that Eps8-DCs exert synergistic effect on CD19 targeting CAR-T cells and paves the way for clinical trials using the combination of DC vaccination and engineered T cells in relapsed leukemia.

Cancer stem cell immunology and immunotherapy: Harnessing the immune system against cancer's source

Despite recent advances in diagnosis and therapy having improved cancer outcome, many patients still do not respond to treatments, resulting in the progression or relapse of the disease, eventually impairing survival expectations. The limited efficacy of therapy is often attributable to its inability to affect cancer stem cells (CSCs), a small population of cells resistant to current radio- and chemo-therapies. CSCs are characterized by self-renewal and tumor-initiating capabilities, and function as a reservoir for the local and distant recurrence of the disease. Therefore, new therapeutic approaches able to effectively target and deplete CSCs are urgently needed. Immunotherapy is facing a renewed interest for its potential in cancer treatment, and the possibility of harnessing the immune system to target CSCs is being addressed by a new exciting research field. In this chapter, we discuss the cancer stem cell model and illustrate CSC biological and molecular properties, critically addressing theoretical and practical issues linked with their definition and study. We then review the existing literature regarding the immunological properties of CSCs and the complex interplay occurring between CSCs and immune cells. Finally, we present up-to-date studies on CSC immunotargeting and its potential future perspective. In conclusion, understanding the interplay between CSC biology and tumor immunology will provide a deeper understanding of the mechanisms that regulate CSC immunological properties. This will contribute to the design of new CSC-directed immunotherapeutic strategies with the potential of strongly improving cancer outcomes.

Polyphenols as Immunomodulatory Compounds in the Tumor Microenvironment: Friends or Foes?

Polyphenols are natural antioxidant compounds ubiquitously found in plants and, thus, ever present in human nutrition (tea, wine, chocolate, fruits and vegetables are typical examples of polyphenol-rich foods). Widespread evidence indicate that polyphenols exert strong antioxidant, anti-inflammatory, anti-microbial and anti-cancer activities, and thus, they are generally regarded to as all-purpose beneficial nutraceuticals or supplements whose use can only have a positive influence on the body. A closer look to the large body of results of years of investigations, however, present a more complex scenario where polyphenols exert different and, sometimes, paradoxical effects depending on dose, target system and cell type and the biological status of the target cell. Particularly, the immunomodulatory potential of polyphenols presents two opposite faces to researchers trying to evaluate their usability in future cancer therapies: on one hand, these compounds could be beneficial suppressors of peri-tumoral inflammation that fuels cancer growth. On the other hand, they might suppress immunotherapeutic approaches and give rise to immunosuppressive cell clones that, in turn, would aid tumor growth and dissemination. In this review, we summarize knowledge of the immunomodulatory effects of polyphenols with a particular focus on cancer microenvironment and immunotherapy, highlighting conceptual pitfalls and delicate cell-specific effects in order to aid the design of future therapies involving polyphenols as chemoadjuvants.

Diagnostic and therapeutic applications of miRNA-based strategies to cancer immunotherapy

Cancer immunotherapy has shown impressive clinical results in the last decade, improving both solid and hematologic cancer patients' overall survival. Nevertheless, most of the molecular aspects underlying the response to this approach are still under investigation. miRNAs in particular have been described as regulators of a plethora of different immunologic processes and thus have the potential to be key in the future developments of immunotherapy. In this review, we summarize and discuss the emerging role of miRNAs in the diagnosis and therapeutics of the four principal cancer immunotherapy approaches: immune checkpoint blockade, adoptive cell therapy, cancer vaccines, and cytokine therapy. In particular, this review is focused on potential roles for miRNAs to be adjuvants in soluble factor- and cell-based therapies, with the aim of helping to increase specificity and decrease toxicity, and on the potential for rationally identified miRNA-based diagnostic approaches to aid in precision clinical immunooncology.

Serum cytokine levels as predictive biomarkers of benefit from ipilimumab in small cell lung cancer

Background. Immunotherapy has shown efficacy in small cell lung cancer (SCLC), but only a subset of patients benefits. Surrogate biomarkers are urgently needed. Our aim was to evaluate serum Th1, Th2, and proinflammatory cytokines in two cohorts of SCLC patients before and during treatment with chemotherapy with or without ipilimumab and to correlate them with survival. Patients and methods. Two cohorts of SCLC patients were studied: patients treated with chemotherapy (n = 47), and patients treated with chemotherapy plus ipilimumab (n = 37). Baseline, on-treatment and after-treatment serum samples were evaluated for the presence of IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IFN-gamma, TNF-alpha, GM-CSF, and Mip-1alpha using a Luminex assay. Differential changes in cytokines between cohorts were analyzed. Associations between cytokine levels and their changes with overall survival were evaluated. Results. Patients treated with ipilimumab showed a global increase of all cytokines after treatment initiation. A high level of IL-8 at baseline was associated with worse prognosis regardless of treatment. Baseline increased IL-2 levels predicted sensitivity to ipilimumab, while high IL-6 and TNF-alpha predicted resistance. An on-treatment increase in IL-4 levels in patients treated with immune-chemotherapy was associated with a better overall survival. Conclusions. The addition of ipilimumab to standard chemotherapy in SCLC modulates the serum levels of cytokines. Baseline levels and their change over time relate to overall survival. Blood-based biomarkers are convenient for patients, and our results support prospective validation of cytokines as predictive biomarkers for ipilimumab in SCLC.

Functional genomics: paving the way for more successful cancer immunotherapy

Immunotherapies have revolutionized cancer treatment. Immunotherapy is effective for the treatment of a wide range of cancer types and can mediate complete and durable tumor regression. Nonetheless, the field still faces many significant challenges, such as the need for personalized therapeutic strategies and better biomarkers, the difficulty of selecting the right combination therapy, and resistance to currently available immunotherapies. Both cancer and host immunity comprise significantly diverse and complex ecosystems, making immunogenomics an ideal field for functional genomics analysis. In this review, we describe the cancer-immunity cycle, how cancer cells manage to evade immune attack and the current hurdles in the path of cancer immunotherapy. Then, we discuss how functional genomics approaches can pave the way for more successful cancer immunotherapies.

Photothermally activatable PDA immune nanomedicine combined with PD-L1 checkpoint blockade for antimetastatic cancer photoimmunotherapy

Photothermal therapy (PTT) has shown promising potential and bright prospects in damaging primary tumors; however, it is limited to metastatic and recrudescent tumors as PTT requires straightforward light irradiation. Moreover, metastatic and recrudescent tumor immunosuppression due to host T-cell antitumor activity is dramatically impeded because of programmed cell death 1 ligand (PD-L1) and programmed cell death receptor 1 (PD-1) pathways and immune checkpoint blockade (ICB) therapy. In this work, we demonstrate that PTT combined with ICB could not only eliminate primary tumors, but also prevent tumor metastasis to the lungs/liver. In particular, we have designed immunoadjuvant nanomedicine carriers on the basis of polydopamine (PDA) simultaneously loaded with resiquimod (R848)-a kind of toll-like receptor 7 (TLR7) agonist-and carbon dots (CDs)-a fluorescent agent. This nanomedicine is defined as PDA-PEG-R848-CD nanoparticle (NP). The multitasking PDA-PEG-R848-CD NPs can destroy 4T1 breast tumors by PTT under near-infrared laser irradiation in addition to generating tumor-associated antigens. Moreover, the PTT effect triggered the release of R848, thereby inducing a strong antitumor immune response. Meanwhile, this synergistic therapy also shows the abscopal effects by completely inhibiting the growth of untreated distant tumors by effectively triggering the tumors infiltrated by CD3/CD8. Such findings suggest that PDA-PEG-R848-CD NPs could significantly potentiate the systemic therapeutic efficiency of PD-L1 checkpoint blockade therapy by activating both innate and adaptive immune systems in the body.

Effect of Multiple Vaccinations with Tumor Cell-Based Vaccine with Codon-Modified GM-CSF on Tumor Growth in a Mouse Model

Ectopic expression of codon-modified granulocyte-macrophage colony-stimulating factor (cGM-CSF) in TC-1 cells (TC-1/cGM-CSF), a model cell line for human papillomavirus (HPV)-infected cervical cancer cells, increased the expression level of GM-CSF and improved the efficacy of tumor cell-based vaccines in a cervical cancer mouse model. The number of vaccine doses required to induce a long-term immune response in a cervical cancer mouse model is poorly understood. Here, we investigated one, three, and five doses of the irradiated TC-1/cGM-CSF vaccine to determine which dose was effective in inducing a greater immune response and the suppression of tumors. Our findings showed that three doses of irradiated TC-1/cGM-CSF vaccine elicited slower tumor growth rates and enhanced survival rates compared with one dose or five doses of irradiated TC-1/cGM-CSF vaccine. Consistently, mice vaccinated with three doses of irradiated TC-1/cGM-CSF vaccine exhibited stronger interferon gamma (IFN-γ) production in HPV E7-specific CD8⁺ T cells and CD4⁺ T cells. A higher percentage of natural killer cells and interferon-producing killer dendritic cells (IKDCs) appeared in the splenocytes of the mice vaccinated with three doses of irradiated TC-1/cGM-CSF vaccine compared with those of the mice vaccinated with one dose or five doses of irradiated TC-1/cGM-CSF vaccine. Our findings demonstrate that single or multiple vaccinations, such as five doses, with irradiated TC-1/cGM-CSF vaccine suppressed the immune response, whereas three doses of irradiated TC-1/cGM-CSF vaccine elicited a greater immune response and subsequent tumor suppression.

A microparticle platform for STING-targeted immunotherapy enhances natural killer cell- and CD8+ T cell-mediated anti-tumor immunity

Immunotherapies have significantly improved cancer patient survival, but response rates are still limited. Thus, novel formulations are needed to expand the breadth of immunotherapies. Pathogen associated molecular patterns (PAMPs) can be used to stimulate an immune response, but several pathogen recognition receptors are located within the cell, making delivery challenging. We have employed the biodegradable polymer acetalated dextran (Ace-DEX) to formulate PAMP microparticles (MPs) in order to enhance intracellular delivery. While treatment with four different PAMP MPs resulted in tumor growth inhibition, cyclic GMP-AMP (cGAMP) MPs were most effective. cGAMP MPs showed anti-tumor efficacy at doses 100-1000 fold lower than published doses of soluble cGAMP in two murine tumor models. Treatment with cGAMP MPs resulted in increased natural killer cell numbers in the tumor environment. Immune cell depletion studies confirmed that NK cells were responsible for the anti-tumor efficacy in an aggressive mouse melanoma model. NK cells and CD8⁺ T cells were both required for early anti-tumor function in a triple negative breast cancer model. In summary, cGAMP MP treatment results in NK and T cell-dependent anti-tumor immune response.

Consumption of β-glucans to spice up T cell treatment of tumors: a review

INTRODUCTION

Adoptive T-cell treatments of solid cancers have evolved into a robust therapy with objective response rates surpassing those of standardized treatments. Unfortunately, only a limited fraction of patients shows durable responses, which is considered to be due to a T cell-suppressive tumor microenvironment (TME). Here we argue that naturally occurring β-glucans can enable reversion of such T cell suppression by engaging innate immune cells and enhancing numbers and function of lymphocyte effectors.

AREAS COVERED

This review summarizes timely reports with respect to absorption, trafficking and immune stimulatory effects of β-glucans, particularly in relation to innate immune cells. Furthermore, we list effects toward well-being and immune functions in healthy subjects as well as cancer patients treated with orally administered β-glucans, extended with effects of β-glucan treatments in mouse cancer models.

EXPERT OPINION

Beta-glucans, when present in food and following uptake in the proximal gut, stimulate immune cells present in gut-associated lymphoid tissue and initiate highly conserved pro-inflammatory pathways. When tested in mouse cancer models, β-glucans result in better control of tumor growth and shift the TME toward a T cell-sensitive environment. Along these lines, we advocate that intake of β-glucans provides an accessible and immune-potentiating adjuvant when combined with adoptive T-cell treatments of cancer.

Delivery technologies for cancer immunotherapy

Immunotherapy has become a powerful clinical strategy for treating cancer. The number of immunotherapy drug approvals has been increasing, with numerous treatments in clinical and preclinical development. However, a key challenge in the broad implementation of immunotherapies for cancer remains the controlled modulation of the immune system, as these therapeutics have serious adverse effects including autoimmunity and nonspecific inflammation. Understanding how to increase the response rates to various classes of immunotherapy is key to improving efficacy and controlling these adverse effects. Advanced biomaterials and drug delivery systems, such as nanoparticles and the use of T cells to deliver therapies, could effectively harness immunotherapies and improve their potency while reducing toxic side effects. Here, we discuss these research advances, as well as the opportunities and challenges for integrating delivery technologies into cancer immunotherapy, and we critically analyse the outlook for these emerging areas.

Enhancing the pro-inflammatory anti-cancer T cell response via biomanufactured, secretome-based, immunotherapeutics

T lymphocytes play a critical role in the pro-inflammatory anti-cancer response; hence, significant pharmacologic efforts have been made to enhance the endogenous T cell response. Unfortunately, significant toxicity arises consequent to pan T cell activation. In contrast, the less robust T cell alloresponse has also demonstrated an anti-cancer effect, but poses an inherent risk of GvHD. To overcome the GvHD risk, an acellular pro-inflammatory agent (IA1) has been biomanufactured from the secretome of the allorecognition response. To assess IA1's immunomodulatory activity, T cell proliferation and differentiation were determined in vitro. The pro-inflammatory properties of the IA1 therapeutic were mediated by the miRNA-enriched fractions. Moreover, cross-species efficacy was observed consequent to the evolutionary conservation of miRNA. IA1 exerted no toxicity to resting PBMC but induced significant proliferation of resting CD3⁺ (CD4⁺ and CD8⁺) T cells and skewed the response towards a pro-inflammatory state (i.e., increased Teff:Treg ratio). Crucially, IA1-activated PBMC demonstrated a potent inhibition of cancer cell (HeLa and SH-4 melanoma) proliferation relative to the resting PBMC. The anti-proliferation effect of IA1-activated PBMC was noted within ˜12 h versus 4-5 days for resting cells. A second biomanufactured therapeutic (IA2; produced using HeLa cells) surprisingly demonstrated direct toxicity to cancer cells but was less effective than IA1 in inducing a cell-mediated response. This study demonstrates that miRNA-enriched therapeutics can be biomanufactured from the secretome and can induce a potent pro-inflammatory, anti-cancer, effect on resting lymphocytes.