Sustained delivery of IL-1 Ra from biodegradable microspheres reduces the number of murine B16 melanoma lung metastases

Interleukin-1 receptor antagonist: An alternative therapy for cancer treatment

The interleukin-1 receptor antagonist (IL-1Ra) is an anti-inflammatory cytokine and a naturally occurring antagonist of the IL-1 receptor. It effectively counteracts the IL-1 signaling pathway mediated by IL-1α/β. Over the past few decades, accumulating evidence has suggested that IL-1 signaling plays an essential role in tumor formation, growth, and metastasis. Significantly, anakinra, the first United States Food and Drug Administration (FDA)-approved IL-1Ra drug, has demonstrated promising antitumor effects in animal studies. Numerous clinical trials have subsequently incorporated anakinra into their cancer treatment protocols. In this review, we comprehensively discuss the research progress on the role of IL-1 in tumors and summarize the significant contribution of IL-1Ra (anakinra) to tumor immunity. Additionally, we analyze the potential value of IL-1Ra as a biomarker from a clinical perspective. This review is aimed to highlight the important link between inflammation and cancer and provide potential drug targets for future cancer therapy.

NLRP3 and cancer: Pathogenesis and therapeutic opportunities

More than a decade ago IL-1 blockade was suggested as an add-on therapy for the treatment of cancer. This proposal was based on the overall safety record of anti-IL-1 biologics and the anti-tumor properties of IL-1 blockade in animal models of cancer. Today, a new frontier in IL-1 activity regulation has developed with several orally active NLRP3 inhibitors currently in clinical trials, including cancer. Despite an increasing body of evidence suggesting a role of NLRP3 and IL-1-mediated inflammation driving cancer initiation, immunosuppression, growth, and metastasis, NLRP3 activation in cancer remains controversial. In this review, we discuss the recent advances in the understanding of NLRP3 activation in cancer. Further, we discuss the current opportunities for NLRP3 inhibition in cancer intervention with novel small molecules.

Risk of Cardiovascular Disease Death in Older Malignant Melanoma Patients: A Population-Based Study

Noncancer deaths account for a large proportion of deaths in patients with malignant melanoma (MM), but the risk of cardiovascular disease (CVD) death in older MM patients remains unclear. This study aimed to estimate the risk of CVD death in older MM patients. Data on older MM patients were obtained in the Surveillance, Epidemiology, and End Results database. Risk of CVD death was calculated by standardized mortality rates (SMRs), cumulative mortality and proportion of different causes of death. MM patients had a higher risk of CVD death than general populations (SMR = 1.98; 95% CI 1.93−2.03, p < 0.001). CVD death was more common in MM patients who were diagnosed at age 85 or older, had a localized stage, were white, had surgical treatment, had a primary head/neck/upper limb site and had a low-grade and superficial spreading/lentigo malignant pathologic type. Cumulative CVD mortality was more common than primary cancer in all older age groups, male or female, and patients with localized-stage disease. Other than primary cancer, CVD was the main cause of death in older patients diagnosed with MM. Our findings highlight CVD death is an important competing event of deaths in older MM patients, and more attention should be paid to reducing CVD death to improve survival.

Evaluation of the Effect of Wheat Germ Oil and Olmutinib on the Thioacetamide-Induced Liver and Kidney Toxicity in Mice

Thioacetamide (TAA) intoxication produces a reproducible standard animal model of induced liver and kidney injuries where free radicals are produced by phase I oxidation reactions, which eventually leads to liver and kidney failure. Wheat germ oil (WGO) is a unique food supplement with concentrated nutrient efficiency and has remarkable antioxidant functions. Olmutinib, on the other hand, is a chemotherapy drug considered safe for kidneys and the liver. Therefore, in this study, WGO and olmutinib were investigated for their effect on TAA-induced liver and kidney damage. Inflammatory markers; interleukin-1 beta (IL-1β); IL-6; and the levels of enzymatic markers ALT (Alanine aminotransferase), AST (Aspartate aminotransferase), LDH (Lactate dehydrogenase), and CK (creatinine kinase) in serum for liver and kidney were analyzed and evaluated along with histopathological changes in the tissue. Thirty male mice 4–6 weeks of age were grouped into five groups of six animals: the control group (saline) and the other groups (Groups II to V), which were given thioacetamide for two weeks. In addition, Group II continued with TAA; Group III was given olmutinib (30 mg/kg), Group IV was given the wheat germ oil (WGO) (1400 mg/kg), and Group V was given (olmutinib (30 mg/kg) + WGO (1400 mg/kg)) for five days. The results suggested that olmutinib treatment potentiated TAA-induced liver and kidney injury. At the same time, WGO efficiently alleviated TAA and TAA–olmutinib toxicity in Groups IV and V. The histological studies also showed reduced damage with WGO in the animal model. Hence, it was concluded that WGO could significantly reduce liver and kidney damage caused by TAA and olmutinib in mice.

Characterization of a Novel Interleukin-1 Receptor Antagonist from Sheep (Ovis aries)

Interleukin-1 receptor antagonist (IL-1Ra) is an antagonist of IL-1β binding IL-1β receptors but does not induce intracellular responses or signal transduction. In this study, the full-length complementary DNA (cDNA) of the IL-1Ra gene (OaIL-1Ra) was identified from sheep (Ovis aries) using rapid amplification of cDNA ends PCR and submitted to GenBank with the accession number KC425613. The OaIL-1Ra cDNA comprised an open reading frame of 525 bp encoding a protein of 19765.8 Da, a 5'-untranslated region (UTR) of 27 bp, and a 3'-UTR of 676 bp with a poly(A) tail. Recombinant OaIL-1Ra with bioactivity was expressed in a prokaryotic expression system, and a monoclonal antibody against native OaIL-1Ra was prepared. Through Western blot analyses, the OaIL-1Ra protein was widely expressed in lung, heart, spleen, liver, kidney, muscle, intestine, lymphonodi, rumen, and white blood cells, with the highest levels in liver and spleen. The expression of OaIL-1Ra in primary cultured white blood cells of sheep were highly induced in a time-dependent manner when challenged with different bacteria. These results implied that OaIL-1Ra is associated with immune responses during bacterial infections.

IL-1 Signaling in Tumor Microenvironment

Interleukin 1 (IL-1) has long been known for its pleiotropic effects on inflammation that plays a complex, and sometimes contrasting, role in different stages of cancer development. As a major proinflammatory cytokine, IL-1β is mainly expressed by innate immune cells. IL-1α, however, is expressed by various cell types under physiological and pathological conditions. IL-1R1 is the main receptor for both ligands and is expressed by various cell types, including innate and adaptive immune cell types, epithelial cells, endothelial cells, adipocytes, chondrocytes, fibroblasts, etc. IL-1 and IL-1R1 receptor interaction leads to a set of common signaling pathways, mainly the NF-kB and MAP kinase pathways, as a result of complex positive and negative regulations. The variety of cell types with IL-1R1 expression dictates the role of IL-1 signaling at different stages of cancer, which under certain circumstances leads to contrasting roles in tumor development. Recent availability of IL-1R1 conditional knockout mouse model has made it possible to dissect the role of IL-1/IL-1R1 signaling transduction in different cell types within the tumor microenvironment. This chapter will focus on the role of IL-1/IL-1R1 in different cell types within the tumor microenvironment and discuss the potential of targeting this pathway in cancer therapy.

Serum proteomic analysis of melanoma patients with immunohistochemical profiling of primary melanomas and cultured cells: Pilot study

The steadily increasing incidence of malignant melanoma (MM) and its aggressive behaviour makes this tumour an attractive cancer research topic. The tumour microenvironment is being increasingly recognised as a key factor in cancer biology, with an impact on proliferation, invasion, angiogenesis and metastatic spread, as well as acquired therapy resistance. Multiple bioactive molecules playing cooperative roles promote the chronic inflammatory milieu in tumours, making inflammation a hallmark of cancer. This specific inflammatory setting is evident in the affected tissue. However, certain mediators can leak into the systemic circulation and affect the whole organism. The present study analysed the complex inflammatory response in the sera of patients with MM of various stages. Multiplexed proteomic analysis (Luminex Corporation) of 31 serum proteins was employed. These targets were observed in immunohistochemical profiles of primary tumours from the same patients. Furthermore, these proteins were analysed in MM cell lines and the principal cell population of the melanoma microenvironment, cancer‑associated fibroblasts. Growth factors such as hepatocyte growth factor, granulocyte‑colony stimulating factor and vascular endothelial growth factor, chemokines RANTES and interleukin (IL)‑8, and cytokines IL‑6, interferon‑α and IL‑1 receptor antagonist significantly differed in these patients compared with the healthy controls. Taken together, the results presented here depict the inflammatory landscape that is altered in melanoma patients, and highlight potentially relevant targets for therapy improvement.

NF-κB p65 and p105 implicate in interleukin 1β-mediated COX-2 expression in melanoma cells

Inflammatory and microenvironmental factors produced by cancer cells are thought to directly or indirectly promote cancer cell growth. Prostaglandins, including prostaglandin E2, have key roles as a microenvironment factor in influencing the development of tumors, and are produced by the rate limiting enzyme cyclooxygenase 2 (COX-2). In this study, we used canine melanoma cells treated with the proinflammatory cytokine interleukin 1β (IL-1β) and investigated the transcriptional factor nuclear factor-κB (NF-κB) signaling in IL-1β-induced COX-2 expression. IL-1β induced prostaglandin E2 release and COX-2 mRNA expression in a time- and dose-dependent manner. In the cells treated with the NF-κB inhibitors BAY11-7082 and TPC-1, IL-1β-mediated prostaglandin E2 release and COX-2 mRNA expression were inhibited. IL-1β also provoked phosphorylation of p65/RelA and p105/NF-κB1, which are members of the NF-κB families. The IL-1β-induced phosphorylation of p65 and p105 was attenuated in the presence of both NF-κB inhibitors. In melanoma cells transfected with siRNA of p65 or p105, IL-1β-mediated COX-2 mRNA expression was inhibited. These findings suggest that canonical activation of NF-κB signaling plays a crucial role for inflammatory states in melanoma cells.

Potentiating and synergistic effect of grapefruit juice on the antioxidant and anti-inflammatory activity of aripiprazole against hydrogen peroxide induced oxidative stress in mice

BACKGROUND

Dependence on antipsycotic drugs like aripriprazole (ARI) is increasing at alarming rate, hence, this study was undertaken to support the hypothesis that supplementation of Citrus paradisi (Grapefruit) juice having high concentration of polyphenols might potentiate and synergize the therapeutic effect of ARI, by increasing its bioavailability and inherent antioxidant potential. These benefits together might decrease the daily dosage of the ARI and thus alleviate the possible side effects of drug.

METHODS

In this study the antioxidant and anti-inflammatory potential of ARI alone and in combination with GFJ was evaluated for hydrogen peroxide (H₂O₂) induced oxidative stress in mice. Seventy mice (4 weeks old), were randomly divided into seven groups. Group I: Control; Group II: H₂O₂ treated; Group III; ARI treated; Group IV GFJ treated; Group V: GFJ and H₂O₂ treated; Group VI; ARI and H₂O₂ treated; Group VII; ARI, GFJ and H₂O₂ treated. Serum levels of alanine aminotransferase (ALT), blood urea nitrogen (BUN), creatinine kinase (CK), creatinine and total protein were measured. Furthermore, pro-inflammatory cytokines Interleukin (IL)-1α, IL-2, IL-10 and tumor necrosis factor-α (TNF-α) concentrations were also measured.

RESULTS

The mice group that was treated with ARI, GFJ or combination of the two showed significant improvement in the H₂O₂ altered parameters with the combination group showing more significant improvement than the ARI and GFJ alone groups indicating a synergistic and potentiating effect of the antioxidant and anti-inflammatory potential of GFJ on ARI.

CONCLUSION

Supplementing GFJ to ARI might increase an anti-oxidative potential of ARI due to inherent antioxidant and anti-inflammatory activity of GFJ and thus could alleviate the possible dosage dependent side effects of ARI.

Immune profiling of melanoma tumors reflecting aggressiveness in a preclinical model

Melanoma, like most solid tumors, is highly heterogeneous in terms of invasive, proliferative, and tumor-initiating potential. This heterogeneity is the outcome of differential gene expression resulting from conditions in the tumor microenvironment and the selective pressure of the immune system. To investigate possible signatures combining immune-related gene expression and lymphocyte infiltration, we established a preclinical model using B16.F1-derived clones, in the context of melanoma aggressiveness. Combinatorial analyses revealed that tumors concomitantly expressing low levels of Tnf-a, Pd-1, Il-10, Il-1ra, Ccl5, Ido, high Il-9, and with low infiltration by CD45+, CD3+, CD4+ and CD8+ cells and a high CD4+:CD8+ T cell ratio exhibited the most aggressive growth characteristics. Overall, these results support the notion that the intratumoral immunologic network molds aggressive melanoma phenotypes.

Self-Assembled Raspberry-Like Core/Satellite Nanoparticles for Anti-Inflammatory Protein Delivery

Functional proteins are very promising for protein therapeutics; however, effective delivery of therapeutic proteins remains challenging. Herein, we developed novel core/satellite nanoparticles by tethering therapeutic proteins to the core/shell polymeric particle surface through cucurbit[8]uril (CB[8])-mediated host-guest interactions. The effectiveness of the core/satellite nanoparticles as protein carrier was demonstrated through the intra-articular delivery of interleukin-1 receptor antagonist (IL-1Ra). We showed that IL-1Ra can effectively self-assemble onto the surface of the polymeric nanoparticles and maintained good protein bioactivity by inhibiting IL-1-mediated signaling. More importantly, in vivo results revealed that IL-1Ra-bounded core/satellite nanoparticles could significantly increase the retention time of IL-1Ra in the rat stifle joint compared to soluble IL-1Ra, which could greatly improve the efficacy of IL-1Ra. These results indicate that the facile host-guest self-assembly can be exploited as an effective approach for realizing the therapeutic potential of proteins.

Intra-articular interleukin-1 receptor antagonist (IL1-ra) microspheres for posttraumatic osteoarthritis: in vitro biological activity and in vivo disease modifying effect

Background

Interleukin-1 receptor antagonist (IL-1 ra) can be disease-modifying in posttraumatic osteoarthritis (PTOA). One limitation is its short joint residence time. We hypothesized that IL-1 ra encapsulation in poly (lactide-co-glycolide) (PLGA) microspheres reduces IL-1 ra systemic absorption and provides an enhanced anti-PTOA effect.

Methods

IL-1 ra release kinetics and biological activity: IL-1 ra encapsulation into PLGA microsphere was performed using double emulsion solvent extraction. Lyophilized PLGA IL-1 ra microspheres were resuspended in PBS and supernatant IL-1 ra concentrations were assayed. The biological activity of IL-1 ra from PLGA IL-1 ra microspheres was performed using IL-1 induced lymphocyte proliferation and bovine articular cartilage degradation assays. Systemic absorption of IL-1 ra following intra-articular (IA) injection of PLGA IL-1 ra or IL-1 ra: At 1, 3, 6, 12 and 24 h following injection of 50 μl PLGA IL-1 ra (n = 6) or IL-1 ra (n = 6), serum samples were collected and IL-1 ra concentrations were determined. Anterior cruciate ligamenttransection (ACLT) and IA dosing: ACLT was performed in 8–10 week old male Lewis rats (n = 42). PBS (50 μl; n = 9), IL-1 ra (50 μl; 5 mg/ml; n = 13), PLGA IL-1 ra (50 μl; equivalent to 5 mg/ml IL-1 ra; n = 14) or PLGA particles (50 μl; n = 6) treatments were performed on days 7, 14, 21 and 28 following ACLT. Cartilage and synovial histopathology: On day 35, animal ACLT joints were harvested and tibial cartilage and synovial histopathology scoring was performed.

Results

Percent IL-1 ra content in the supernatant at 6 h was 13.44 ± 9.27 % compared to 34.16 ± 12.04 %, 47.89 ± 12.71 %, 57.14 ± 11.71 %, and 93.90 ± 8.50 % at 12, 24, 48 and 72 h, respectively. PLGA IL-1 ra inhibited lymphocyte proliferation and cartilage degradation similar to IL-1 ra. Serum IL-1 ra levels were significantly lower at 1, 3, and 6 h following PLGA IL-1 ra injection compared to IL-1 ra. Cartilage and synovial histopathology scores were significantly lower in the PLGA IL-1 ra group compared to PBS and PLGA groups (p < 0.001).

Conclusions

IL-1 ra encapsulation in PLGA microspheres is feasible with no alteration to IL-1 ra biological activity. PLGA IL-1 ra exhibited an enhanced disease-modifying effect in a PTOA model compared to similarly dosed IL-1 ra.

Hematological Effects, Serum, and Pulmonary Cytokine Profiles in a Melanoma Mouse Model Treated with GK1

OBJECTIVE

In a previous study, we demonstrated the therapeutic efficacy of a subcutaneous injection of GK1 peptide in a melanoma mouse model, effectively increasing the mean survival time by 42.58%, delaying tumor growth, and increasing intratumoral necrosis compared with the control. As a first approach to investigate the anti-melanoma effect of GK1, this study was carried out to determine the hematological effects along with both serum and lung cytokine profiles in a melanoma lung metastatic model.

MATERIALS AND METHODS

Thirteen C57BL6 female mice were transfected in the lateral tail vein with 2×10(5) B16-F0 melanoma cells. After 7 days, mice were separated in two different groups and treatments were initiated (day 0): The GK1-treated group (seven mice) were injected every 5 days intravenously with GK1 (10 μg) in the lateral tail vein, and the control group (six mice) were injected every 5 days with intravenous saline solution. Blood samples were collected every 5 days from day 0; tumor samples were obtained for cytokine measurements on the day of sacrifice.

RESULTS

In the peripheral blood, mice treated with GK1 presented a statistically significant decrease in IFN-γ (p<0.05), and lymphocytes tended to be lower compared with the control mice (p=0.06). Lung metastatic analysis demonstrated a significant increase in IFN-γ and IL-12p70 (p<0.05); a significant decrease in IL-17, IL-4, IL-22, IL-23, and IL-12p40 (p<0.05); and a marginal decrease in IL-1β (p=0.07) compared with the control.

DISCUSSION

Our results suggest that an intratumoral increase of cytokines with antitumor activity along with an intratumoral decrease of cytokines with protumor activity could explain, in part, the anti-melanoma effects of GK1 in a lung metastatic melanoma mouse model. Further studies must be performed to elucidate the precise mechanisms of action for GK1 peptide against melanoma, and their eventual application in humans.

Methoxy poly (ethylene glycol)-block-poly (glutamic acid)-graft-6-(2-nitroimidazole) hexyl amine nanoparticles for potential hypoxia-responsive delivery of doxorubicin

Tumor microenvironment-responsive nano drug delivery vehicles are gaining mounting attention in the field of biomedical sciences. The hypoxic response of the tumorous cells due to very low partial pressure of oxygen (some time less than 2.5 mm of Hg) in the tumor tissues makes hypoxia-responsive drug delivery system as the more appealing in cancer chemotherapy. Based on these considerations, we synthesized hypoxia-responsive polymeric materials methoxy poly (ethylene glycol)-block-poly (glutamic acid)-graft-6-(2-nitroimidazole) hexyl amine (mPEG-b-PLG-g-NID) by conjugation of the hydrophobic nitro imidazole derivative (NID)[6-(2-nitroimidazole) hexyl amine] with the pendant carboxylic group of poly (ethylene glycol)-block-poly (L-glutamic acid)(mPEG-b-PLG). The structure and degree of substitution were confirmed by proton NMR, FTIR, and UV-Vis spectroscopy. The degree of substitution was found to enhance with the increase in NID to polymer ratio. The hypoxia response of the material was evaluated by UV-Vis spectroscopy and zeta potential measurements. Doxorubicin was hydrophobically encapsulated in the micellar core of the hypoxia-responsive nanoparticles. The drug-loaded micelles showed faster release in hypoxic condition as compared to normoxic conditions. Moreover, the developed polymeric system was found non-toxic to MCF-7 cell line, thus suggesting its biocompatibility and suitability as drug delivery device.

Synthesis of self-assembled IL-1Ra-presenting nanoparticles for the treatment of osteoarthritis

Osteoarthritis is a progressive joint disease that results in degradation of cartilage in load-bearing joints. Pain and inflammation in the joint are the hallmarks of this condition, which further exacerbate the cartilage destruction and health of the patient. It is hence imperative to treat the joint inflammation at the earliest. Interleukin 1 (IL-1) blockade by IL-1 receptor antagonist (IL-1Ra) has shown promise in the clinic but this therapy suffers from rapid clearance, high doses, and frequent intervention. Use of carrier particles that result in longer residence time has been proposed. Here we have synthesized a new class of nanoparticles presenting IL-1Ra on the surface and with tunable size from 300 to 700 nm. These IL-1Ra-poly(2-hydroxyethyl methacrylate)-pyridine nanoparticles are cytocompatible and stable in serum-containing solutions for several days. Our results further demonstrate that these nanoparticles are capable of blocking IL-1β signaling in an NF-κB inducible reporter cell line. These engineered nanoparticles are promising for localized intra-articular delivery in joint space to reduce inflammation in osteoarthritis and other inflammatory diseases. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 595-599, 2016.

Recombinant interleukin-1 receptor antagonist conjugated to superparamagnetic iron oxide nanoparticles for theranostic targeting of experimental glioblastoma

Cerebral edema commonly accompanies brain tumors and contributes to neurologic symptoms. The role of the interleukin-1 receptor antagonist conjugated to superparamagnetic iron oxide nanoparticles (SPION-IL-1Ra) was assessed to analyze its anti-edemal effect and its possible application as a negative contrast enhancing agent for magnetic resonance imaging (MRI). Rats with intracranial C6 glioma were intravenously administered at various concentrations of IL-1Ra or SPION-IL-1Ra. Brain peritumoral edema following treatment with receptor antagonist was assessed with high-field MRI. IL-1Ra administered at later stages of tumor progression significantly reduced peritumoral edema (as measured by MRI) and prolonged two-fold the life span of comorbid animals in a dose-dependent manner in comparison to control and corticosteroid-treated animals (P < .001). Synthesized SPION-IL-1Ra conjugates had the properties of negative contrast agent with high coefficients of relaxation efficiency. In vitro studies of SPION-IL-1Ra nanoparticles demonstrated high intracellular incorporation and absence of toxic influence on C6 cells and lymphocyte viability and proliferation. Retention of the nanoparticles in the tumor resulted in enhanced hypotensive T2-weighted images of glioma, proving the application of the conjugates as negative magnetic resonance contrast agents. Moreover, nanoparticles reduced the peritumoral edema confirming the therapeutic potency of synthesized conjugates. SPION-IL-1Ra nanoparticles have an anti-edemal effect when administered through a clinically relevant route in animals with glioma. The SPION-IL-1Ra could be a candidate for theranostic approach in neuro-oncology both for diagnosis of brain tumors and management of peritumoral edema.

Curcumin blocks interleukin-1 signaling in chondrosarcoma cells

Interleukin (IL)-1 signaling plays an important role in inflammatory processes, but also in malignant processes. The essential downstream event in IL-1 signaling is the activation of nuclear factor (NF)-κB, which leads to the expression of several genes that are involved in cell proliferation, invasion, angiogenesis and metastasis, among them VEGF-A. As microenvironment-derived IL-1β is required for invasion and angiogenesis in malignant tumors, also in chondrosarcomas, we investigated IL-1β-induced signal transduction and VEGF-A expression in C3842 and SW1353 chondrosarcoma cells. We additionally performed in vitro angiogenesis assays and NF-κB-related gene expression analyses. Curcumin is a substance which inhibits IL-1 signaling very early by preventing the recruitment of IL-1 receptor associated kinase (IRAK) to the IL-1 receptor. We demonstrate that IL-1 signaling and VEGF-A expression are blocked by Curcumin in chondrosarcoma cells. We further show that Curcumin blocks IL-1β-induced angiogenesis and NF-κB-related gene expression. We suppose that IL-1 blockade is an additional treatment option in chondrosarcoma, either by Curcumin, its derivatives or other IL-1 blocking agents.

The role IL-1 in tumor-mediated angiogenesis

Tumor angiogenesis is one of the hallmarks of tumor progression and is essential for invasiveness and metastasis. Myeloid inflammatory cells, such as immature myeloid precursor cells, also termed myeloid-derived suppressor cells (MDSCs), neutrophils, and monocytes/macrophages, are recruited to the tumor microenvironment by factors released by the malignant cells that are subsequently “educated” in situ to acquire a pro-invasive, pro-angiogenic, and immunosuppressive phenotype. The proximity of myeloid cells to endothelial cells (ECs) lining blood vessels suggests that they play an important role in the angiogenic response, possibly by secreting a network of cytokines/chemokines and inflammatory mediators, as well as via activation of ECs for proliferation and secretion of pro-angiogenic factors. Interleukin-1 (IL-1) is an “alarm,” upstream, pro-inflammatory cytokine that is generated primarily by myeloid cells. IL-1 initiates and propagates inflammation, mainly by inducing a local cytokine network and enhancing inflammatory cell infiltration to affected sites and by augmenting adhesion molecule expression on ECs and leukocytes. Pro-inflammatory mediators were recently shown to play an important role in tumor-mediated angiogenesis and blocking their function may suppress tumor progression. In this review, we summarize the interactions between IL-1 and other pro-angiogenic factors during normal and pathological conditions. In addition, the feasibility of IL-1 neutralization approaches for anti-cancer therapy is discussed.

Feasibility of Applying Helper-Dependent Adenoviral Vectors for Cancer Immunotherapy

Adenoviruses (Ads) infect a broad range of tissue types, and derived vectors have been extensively used for gene therapy. Helper-dependent Ad vectors (HDAds), devoid of viral coding sequences, allow for insertion of large or multiple transgenes in a single vector and have been preclinically used for the study of genetic disorders. However, the clinical application of Ad vectors including HDAds for genetic disorders has been hampered by an acute toxic response. This characteristic, while disadvantageous for gene replacement therapy, could be strategically advantageous for the activation of an immune response if HDAds were used as an adjunct treatment in cancer. Cancer treatments including immunotherapy are frequently limited by the inhibitory environment produced by both tumors and their stroma, each of which express numerous inhibitory molecules. Hence, multiple inhibitory mechanisms must be overcome for development of anti-tumor immunity. The large coding capacity of HDAds can accommodate multiple immune modulating transgenes that could produce a combined effect to overcome tumor-derived inhibition and ensure intratumoral effector T-cell proliferation and function. In this review, we discuss the potential advantages of HDAds to cancer immunotherapy based on potent host immune responses to Ads.

Licensing Adaptive Immunity by NOD-Like Receptors

The innate immune system is composed of a diverse set of host defense molecules, physical barriers, and specialized leukocytes and is the primary form of immune defense against environmental insults. Another crucial role of innate immunity is to shape the long-lived adaptive immune response mediated by T and B lymphocytes. The activation of pattern recognition receptors (PRRs) from the Toll-like receptor family is now a classic example of innate immune molecules influencing adaptive immunity, resulting in effective antigen presentation to naïve T cells. More recent work suggests that the activation of another family of PRRs, the NOD-like receptors (NLRs), induces a different set of innate immune responses and accordingly, drives different aspects of adaptive immunity. Yet how this unusually diverse family of molecules (some without canonical PRR function) regulates immunity remains incompletely understood. In this review, we discuss the evidence for and against NLR activity orchestrating adaptive immune responses during infectious as well as non-infectious challenges.

IL-1Ra and its delivery strategies: inserting the association in perspective

Interleukin-1 receptor antagonist (IL-1Ra) is a naturally occurring anti-inflammatory antagonist of interleukin-1 family of pro-inflammatory cytokines. The broad spectrum anti-inflammatory effects of IL-1Ra have been investigated against various auto-immune diseases such as diabetes mellitus, rheumatoid arthritis. Despite of its outstanding broad spectrum anti-inflammatory effects, IL-1Ra has short biological half-life (4-6 h) and to cope with this problem, up till now, many delivery strategies have been applied either to extend the half-life and/or prolong the steady-state sustained release of IL-1Ra from its target site. Here in our present paper, we have provided an overview of all approaches attempted to prolong the duration of therapeutic effects of IL-1Ra either by fusing IL-1Ra using fusion protein technology to extend the half-life and/or development of new dosage forms using various biodegradable polymers to prolong its steady-state sustained release at the site of administration. These approaches have been characterized by their intended impact on either in vitro release characteristics and/or pharmacokinetic and pharmacodynamic parameters of IL-1Ra. We have also compared these delivery strategies with each other on the basis of bioactivity of IL-1Ra after fusion with fusion protein partner and/or encapsulation with biodegradable polymer.

The role of interleukin-1β in arthritic pain: main involvement in thermal, but not mechanical, hyperalgesia in rat antigen-induced arthritis

OBJECTIVE

Interleukin-1β (IL-1β) is considered a pronociceptive cytokine, but its role in the generation of arthritic pain is unknown. The aim of this study was to investigate the role of IL-1β in arthritic pain and to explore the antinociceptive potential of the IL-1 receptor type I (IL-1RI) antagonist anakinra.

METHODS

Antigen-induced arthritis (AIA) was induced in rats. Expression of IL-1RI in the dorsal root ganglia (DRGs) was determined, and the effects of anakinra on inflammation, pain-related behavior, and receptor expression were assessed. In cultured DRG neurons, the effect of IL-1β on the expression of the transient receptor potential vanilloid 1 (TRPV-1) ion channel was examined. Recordings of action potentials from joint nociceptors were made after intraarticular injection of IL-1β into the rat knee joints.

RESULTS

AIA generated pronounced and persistent mechanical and thermal hyperalgesia, and IL-1RI expression in the lumbar DRGs was significantly up-regulated. Treatment with anakinra did not significantly reduce the severity of arthritis or mechanical hyperalgesia, but did result in a pronounced reduction in thermal hyperalgesia. In cultured DRG neurons, IL-1β up-regulated the expression of TRPV-1, a major transduction molecule involved in thermal hyperalgesia. During AIA, anakinra treatment down-regulated the expression of TRPV-1, consistent with the pronounced reduction in thermal hyperalgesia. IL-1β increased the mechanosensitivity of C-fibers of the joint, but reduced the mechanosensitivity of Aδ-fibers, thus having opposite effects on these mechanonociceptive nerve fibers.

CONCLUSION

In the context of arthritic knee pain, IL-1β and IL-1 receptors appear to be involved in thermal, rather than mechanical, hyperalgesia. Therefore, neutralization of IL-1β may be mainly antinociceptive in disease states characterized by thermal hyperalgesia, but not in disease states mainly characterized by mechanical hyperalgesia.

IL-1ra delivered from poly(lactic-co-glycolic acid) microspheres attenuates IL-1β-mediated degradation of nucleus pulposus in vitro

Introduction

Inflammation plays a key role in the progression of intervertebral disc degeneration, a condition strongly implicated as a cause of lower back pain. The objective of this study was to investigate the therapeutic potential of poly(lactic-co-glycolic acid) (PLGA) microspheres loaded with interleukin-1 receptor antagonist (IL-1ra) for sustained attenuation of interleukin-1 beta (IL-1β) mediated degradative changes in the nucleus pulposus (NP), using an in vitro model.

Methods

IL-1ra was encapsulated in PLGA microspheres and release kinetics were determined over 35 days. NP agarose constructs were cultured to functional maturity and treated with combinations of IL-1β and media conditioned with IL-1ra released from microspheres at intervals for up to 20 days. Construct mechanical properties, glycosaminoglycan content, nitrite production and mRNA expression of catabolic mediators were compared to properties for untreated constructs using unpaired Student's t-tests.

Results

IL-1ra release kinetics were characterized by an initial burst release reducing to a linear release over the first 10 days. IL-1ra released from microspheres attenuated the degradative effects of IL-1β as defined by mechanical properties, glycosaminoglycans (GAG) content, nitric oxide production and mRNA expression of inflammatory mediators for 7 days, and continued to limit functional degradation for up to 20 days.

Conclusions

In this study, we successfully demonstrated that IL-1ra microspheres can attenuate the degradative effects of IL-1β on the NP for extended periods. This therapeutic strategy may be appropriate for treating early-stage, cytokine-mediated disc degeneration. Ongoing studies are focusing on testing IL-1ra microspheres in an in vivo model of disc degeneration, as a prelude to clinical translation.

Deficiency of C-C chemokine receptor 5 suppresses tumor development via inactivation of NF-κB and upregulation of IL-1Ra in melanoma model

To evaluate the relevance of C-C chemokine receptor type 5 (CCR5) expression and tumor development, we compared melanoma growth in CCR5 knockout (CCR5^−/−) mice and wild type (CCR5^+/+) mice. CCR5^−/− mice showed reduced tumor volume, tumor weight, and increased survival rate when compared to CCR5^+/+ mice. We investigated the activation of NF-κB since it is an implicated transcription factor in the regulation of genes involving cell growth, apoptosis, and tumor growth. Significant inhibition of DNA binding activity of NF-κB, and translocation of p50 and p65 into the nucleus through the inhibition of phosphorylation of IκB was found in the melanoma tissues of CCR5^−/− mice compared to melanoma tissues of CCR5^+/+ mice. NF-κB target apoptotic protein expression, such as cleaved caspase-3, cleaved PARP, and Bax, was elevated, whereas the survival protein expression levels, such as Bcl-2, C-IAP1, was decreased in the melanoma tissues of CCR5^−/− mice. Interestingly, we found that the level of IL-1Ra, a tumor growth suppressive cytokine, was significantly elevated in tumor tissue and spleen of CCR5^−/− mice compared to the level in CCR5^+/+ mice. Moreover, infiltration of CD8⁺ cytotoxic T cell and CD57⁺ natural killer cells was significantly increased in melanoma tumor and spleen tissue of CCR5^−/− mice compared to that of CCR5^+/+ mice. Therefore, these results showed that CCR5 deficiency caused apoptotic cell death of melanoma through inhibition of NF-κB and upregulation of IL-1Ra.

Interleukin-1 receptor antagonist: a new therapy for type 2 diabetes mellitus

Various complex mechanisms and their multifactorial pathways decisively provoke low-grade local and systemic inflammation in β-cells of pancreatic islets and peripheral tissues to induce β-cells' dysfunction and apoptosis, insulin resistance, and ultimately, overt type 2 diabetes mellitus (T2DM). Conventional antidiabetic agents are being less popular, as they have some potential adverse effects. Currently, many anti-inflammatory therapeutic modalities are being investigated to abate the infuriating effects of inducers of T2DM and among them, interleukin-1 receptor antagonist (IL-1Ra) is the only one that has been approved by US Food and Drug Administration. We have compared IL-1Ra with other anti-inflammatory agents and conventional antidiabetic agents. Although, IL-1Ra has broad-spectrum anti-inflammatory activities, it also has some limitations due to its short half-life. To overcome the problem of short half-life of IL-1Ra, recently, we fused IL-1Ra in recombinant human serum albumin and expressed it in Pichia pastoris. Its bioactivity was also checked by IL-1-induced A375.S2 apoptotic cells. Furthermore, we have also formulated IL-1Ra with Pluronic F-127-based thermosensitive gel and investigated its in vitro characteristics to prolong its therapeutic effects. Further studies are required to investigate its therapeutic effects against diabetes and diabetes-associated complications.

Constitutive aberrant endogenous interleukin-1 facilitates inflammation and growth in human melanoma

Interleukin (IL)-1-mediated inflammation is proposed to contribute to the development and progression of some cancers. IL-1 family member proteins are known to be expressed constitutively in many melanoma tumor cells, and we hypothesize that these support molecular pathways of inflammation and facilitate tumor growth. To investigate the expression of IL-1α and IL-1β in melanoma patients, and their association with disease progression, immunohistochemical staining was carried out on tissues from 170 patients including benign nevi, primary melanomas, and metastatic melanomas. IL-1β levels were low (or zero) in benign nevi and higher in primary and metastatic melanomas (P < 0.0001). IL-1α was expressed in about 73% of nevi and 55% of metastatic melanomas, with levels significantly higher in primary tumors (P < 0.0001); most (98%) primary melanoma samples were positive for IL-1α. In vitro studies with seven human melanoma cell lines showed that five cell lines expressed IL-1α and IL-1β proteins and mRNA. We identified for the first time several important downstream signaling pathways affected by endogenous IL-1, including reactive oxygen and nitrogen species, COX-2, and phosphorylated NF-κB inhibitor (IκB) and stress-activated protein kinase/c-jun-NH(2)-kinase; all of which were decreased by siRNA to IL-1s. Downregulation of IL-1α, IL-1β, or MyD88 substantially increased p21 and p53 levels. Treatment with IL-1 receptor type I neutralizing antibody or IL-1 pathway-specific siRNAs led to growth arrest in IL-1-positive melanoma cells. Furthermore, blocking the IL-1 pathway increased autophagy in IL-1-positive melanoma cells. These results indicate that the endogenous IL-1 system is functional in most human melanoma and interrupting its signaling inhibits the growth of IL-1-positive melanoma cells.

Effects of interleukin-1 receptor antagonist on tumor stroma in experimental uveal melanoma

PURPOSE

In contrast to many malignancies showing evidence that interleukin-1 (IL-1) promotes progression through effects on tumor vascularity and myeloid suppressor cell populations, in uveal melanoma there is evidence that IL-1 can inhibit progression.

METHODS

The effects of the IL-1 receptor antagonist IL-1ra against the aggressive/invasive MUM2B and the nonaggressive/noninvasive OCM1 uveal melanoma models were examined in vitro and in vivo in mouse xenografts. Vascularity and myeloid suppressor cell populations and their regulators were assessed.

RESULTS

In vitro, IL-1, and IL-1ra did not affect the proliferation of the uveal melanoma cells or their production of IL-1, IL-6, transforming growth factor (TGF) β, or VEGF. In vivo, IL-1ra treatment resulted in substantial growth inhibition of MUM2B tumors; less inhibition was observed against OCM1 tumors. Periodic acid-Schiff loops and CD11b⁺ macrophages within the tumor stroma decreased in vivo; CD31⁺ blood vessels were not altered. IL-1ra treatment in vivo did not affect tumor-derived IL-1, IL-6, TGF-β, or VEGF. In contrast, host IL-1β, IL-6, and tumor necrosis factor decreased. Host VEGF was not altered. Intratumoral IL-12(p40) and CXCL10, markers of host M1 polarization, increased, and intratumoral arginase and CD206, markers of myeloid-derived suppressor cells (MDSC) and M2 macrophage polarization, decreased. IL-1ra treatment in vivo also reduced splenic CD11b⁺Gr1⁺ MDSC.

CONCLUSIONS

IL-1 may play a role in promoting uveal melanoma progression. Inhibiting IL-1 with IL-1ra inhibits tumor growth in vivo but not in vitro. Tumor stroma is modified, myeloid suppressor cells are reduced, and M1 macrophage polarization is increased in vivo.

Microenvironment-derived IL-1 and IL-17 interact in the control of lung metastasis

Inflammatory cytokines modulate immune responses in the tumor microenvironment during progression/metastasis. In this study, we have assessed the role of IL-1 and IL-17 in the control of antitumor immunity versus progression in a model of experimental lung metastasis, using 3LL and B16 epithelial tumor cells. The absence of IL-1 signaling or its excess in the lung microenvironment (in IL-1β and IL-1R antagonist knockout [KO] mice, respectively) resulted in a poor prognosis and reduced T cell activity, compared with WT mice. In IL-1β KO mice, enhanced T regulatory cell development/function, due to a favorable in situ cytokine network and impairment in APC maturation, resulted in suppressed antitumor immunity, whereas in IL-1R antagonist KO mice, enhanced accumulation and activity of myeloid-derived suppressor cells were found. Reduced tumor progression along with improved T cell function was found in IL-17 KO mice, compared with WT mice. In the microenvironment of lung tumors, IL-1 induces IL-17 through recruitment of γ/δ T cells and their activation for IL-17 production, with no involvement of Th17 cells. These interactions were specific to the microenvironment of lung tumors, as in intrafootpad tumors in IL-1/IL-17 KO mice, different patterns of invasiveness were observed and no IL-17 could be locally detected. The results highlight the critical and unique role of IL-1, and cytokines induced by it such as IL-17, in determining the balance between inflammation and antitumor immunity in specific tumor microenvironments. Also, we suggest that intervention in IL-1/IL-17 production could be therapeutically used to tilt this balance toward enhanced antitumor immunity.

The inflammasome component NLRP3 impairs antitumor vaccine by enhancing the accumulation of tumor-associated myeloid-derived suppressor cells

The inflammasome is a proteolysis complex that generates the active forms of the proinflammatory cytokines interleukin (IL)-1β and IL-18. Inflammasome activation is mediated by NLR proteins that respond to microbial and nonmicrobial stimuli. Among NLRs, NLRP3 senses the widest array of stimuli and enhances adaptive immunity. However, its role in antitumor immunity is unknown. Therefore, we evaluated the function of the NLRP3 inflammasome in the immune response using dendritic cell vaccination against the poorly immunogenic melanoma cell line B16-F10. Vaccination of Nlrp3(-/-) mice led to a relative 4-fold improvement in survival relative to control animals. Immunity depended on CD8(+) T cells and exhibited immune specificity and memory. Increased vaccine efficacy in Nlrp3(-/-) hosts did not reflect differences in dendritic cells but rather differences in myeloid-derived suppressor cells (MDSC). Although Nlrp3 was expressed in MDSCs, the absence of Nlrp3 did not alter either their functional capacity to inhibit T cells or their presence in peripheral lymphoid tissues. Instead, the absence of Nlrp3 caused a 5-fold reduction in the number of tumor-associated MDSCs found in host mice. Adoptive transfer experiments also showed that Nlrp3(-/-) MDSCs were less efficient in reaching the tumor site. Depleting MDSCs with an anti-Gr-1 antibody increased the survival of tumor-bearing wild-type mice but not Nlrp3(-/-) mice. We concluded that Nlrp3 was critical for accumulation of MDSCs in tumors and for inhibition of antitumor T-cell immunity after dendritic cell vaccination. Our findings establish an unexpected role for Nlrp3 in impeding antitumor immune responses, suggesting novel approaches to improve the response to antitumor vaccines by limiting Nlrp3 signaling.

Liposomes with high encapsulation capacity for paclitaxel: Preparation, characterisation and in vivo anticancer effect

Paclitaxel (PTX) is approved for the treatment of ovarian and breast cancer. The commercially available preparation of PTX, Cremophor EL(R) is associated with hypersensitivity reactions in spite of a suitable premedication. In general, the developed liposomal PTX formulations are troubled with low PTX encapsulation capacity (maximal content, 3 mol%) and accompanied by PTX crystallisation. The application of "pocket-forming" lipids significantly increased the encapsulation capacity of PTX in the liposomes up to 10 mol%. Stable lyophilised preparation of PTX (7 mol%) encapsulated in the liposomes composed of SOPC/POPG/MOPC (molar ratio, 60:20:20) doped with 5 mol% vitamin E had the size distribution of 180-190 nm (PDI, 0.1) with zeta-potential of -31 mV. Sucrose was found to be a suitable cryoprotectant at the lipid:sugar molar ratios of 1:5-1:10. This liposomal formulation did not show any evidence of toxicity in C57BL/6 mice treated with the highest doses of PTX (100 mg/kg administered as a single dose and 150 mg/kg as a cumulative dose applied in three equivalent doses in 48-h intervals). A dose-dependent anticancer effect was found in both hollow fibre implants and syngenic B16F10 melanoma mouse tumour models.

Is interleukin-1 a good or bad 'guy' in tumor immunobiology and immunotherapy?

The interleukin-1 (IL-1) family consists of two major agonistic proteins, IL-1alpha and IL-1beta, which are pleiotropic and affect mainly inflammation, immunity, and hemopoiesis. The IL-1 receptor antagonist (IL-1Ra) is a physiological inhibitor of pre-formed IL-1. In their secreted form, IL-1alpha and IL-1beta bind to the same receptors and induce the same biological functions. However, the IL-1 molecules differ in their compartmentalization within the producing cell or the microenvironment. Thus, IL-1beta is solely active in its secreted form, whereas IL-1alpha is mainly active in cell-associated forms (intracellular precursor and membrane-bound IL-1) and only rarely as a secreted cytokine, mainly by macrophages/monocytes. IL-1 is abundant at tumor sites, being produced by cellular elements of the tumor microenvironment or by the malignant cells, and it affects not only various phases of the malignant process, such as carcinogenesis, tumor growth, and invasiveness, but also patterns of interactions between malignant cells and the host's immune system. Hence, the effects of the IL-1 molecules on the malignant process are complex and are often of an opposing nature. Comparative studies on the differential roles of malignant cell- or host-derived IL-1alpha and IL-1beta in different stages of the malignant process can subsequently open new avenues for manipulation of IL-1 expression and function in cancer immunotherapy.

IL-1 family in breast cancer: potential interplay with leptin and other adipocytokines

Obesity is associated with an increased risk of breast cancer. interleukin-1 (IL-1), a pro-inflammatory cytokine secreted by adipose tissue, is involved in breast cancer development. There is also convincing evidence that other adipocytokines including leptin not only have a role in haematopoiesis, reproduction and immunity but are also growth factors in cancer. Therefore, IL-1 family and leptin family are adipocytokines which could represent a major link between obesity and breast cancer progression. This minireview provides insight into recent findings on the prognostic significance of IL-1 and leptin in mammary tumours, and discusses the potential interplay between IL-1 family members and adipocyte-derived hormones in breast cancer.

Tumor-host interactions: the role of inflammation

It is well established that interactions between tumor cells and the host tissue stroma play a key role in determining whether and how any given solid malignancy will develop. In most cases, tumor cells hijack stromal cell functions for their own benefit and ultimately dictate the rules of engagement to the host tissue microenvironment. However, the contribution of the different stromal cell components to tumor growth remains to be clarified. Because most solid tumors are accompanied by a local inflammatory response, it has long been thought that inflammation and carcinogenesis are related. If formal proof that cancer can be initiated by inflammation in the absence of exogenous carcinogens is still lacking, there is abundant evidence that the inflammatory response can play a central role in modulating tumor growth and progression. This review will discuss some of the mechanisms whereby inflammation can both enhance and inhibit tumor growth.

Delivery strategies of melanoma vaccines: an overview

For many years, various cancer vaccines have been widely evaluated, however clinical responses remain rare. In this review, we attempt to address the question of which delivery strategies and platforms are feasible to produce clinical response and define the characteristics of the strategy that will induce long-lasting antitumor response. We limit our analysis and discussion to microparticles/nanoparticles, liposomes, heat-shock proteins, viral vectors and different types of adjuvants. This review aims to provide an overview of the specific characteristics, strengths and limitations of these delivery systems, focusing on their impacts on the development of melanoma vaccine. To date, only adoptive T-cell transfer has shown promising clinical outcomes compared to other treatments.